Fiero GXP Swap!
01-31-2008, 08:36 PM
#22
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[FONT="Comic Sans MS"] I LOVE IT!!
You just have to be happy with a builder who puts everything into your car, like it was his own! I think Ryan takes more offense to flames and hater comments on this build than I do! Heck, wouldn't any of you that has put their all into something? And I absolutely love it! Who wouldn't??
You just have to be happy with a builder who puts everything into your car, like it was his own! I think Ryan takes more offense to flames and hater comments on this build than I do! Heck, wouldn't any of you that has put their all into something? And I absolutely love it! Who wouldn't??
01-31-2008, 09:09 PM
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So I'm sure it would be appreciated if you didn't knock somebody else's build months after the fact when you don't even know the budget and parts availability we had to work with for this project. It's easy to armchair-quarterback somebody else's build when it's not your money and it's not your car.
-ryan
I've been going through the build threads over on PFF for a couple of weeks now. I think what you've accomplished with the swap is awesome.
I really want to see performance numbers on this when BLKCOFY gets a chance to take it to the track and/or dyno.
01-31-2008, 09:10 PM
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If I ever do a swap on my Fiero, it'd be an LS4 / 4T65E swap. I gotta finish painting it first. I'm only a few months behind. 
You keeping A/C with this swap?
You keeping A/C with this swap?
01-31-2008, 10:20 PM
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Painting is next up for me this summer. I'll probably spend the spring prepping everthing and replacing loose/rusted body parts and have it professionally sprayed. I'm leaning heavily to a high quality matte satin black...but I've changed my mind about 6 times now! I love the paint work some of you have done to the engine cover. That's a must!
01-31-2008, 10:40 PM
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Why? So we could have a manual trans out of a FWD car that had a 1st gear ratio that would have been worthless with this engine?
On paper, the new FWD 6-speeds Archie uses in his kits are stronger than the Fiero 5-speed getrags, but not by a lot. Nobody has found out just how much stronger they are in real-world testing either. I'm willing to bet this automatic would outlast the 6-speed in question at this power level; assuming the car is driven hard.
Besides, some kind of an adapter to relocate the starter would have been needed in order to use that 6-speed (and one would have need to be custom made from scratch which costs a lot of $$$); and if you were going to need adapters, why not just swap in an LS1 or LS2 instead of a smaller LS4?
Opinions are like (you know what) and everybody has one. Something you would like done to your car may not be compatible with someone else's wants or needs once a budget is factored in. There's a lot of things that COULD have been done in this swap if the customer have had endless funds, but that's not how it is. To tell the truth the owner of this car really wanted a manual transmission. So we discussed his options for this and their costs vs. using the 4T65-E TAPShift trans and HE made the decisions to do what was done.
On paper, the new FWD 6-speeds Archie uses in his kits are stronger than the Fiero 5-speed getrags, but not by a lot. Nobody has found out just how much stronger they are in real-world testing either. I'm willing to bet this automatic would outlast the 6-speed in question at this power level; assuming the car is driven hard.
Besides, some kind of an adapter to relocate the starter would have been needed in order to use that 6-speed (and one would have need to be custom made from scratch which costs a lot of $$$); and if you were going to need adapters, why not just swap in an LS1 or LS2 instead of a smaller LS4?
Opinions are like (you know what) and everybody has one. Something you would like done to your car may not be compatible with someone else's wants or needs once a budget is factored in. There's a lot of things that COULD have been done in this swap if the customer have had endless funds, but that's not how it is. To tell the truth the owner of this car really wanted a manual transmission. So we discussed his options for this and their costs vs. using the 4T65-E TAPShift trans and HE made the decisions to do what was done.
I now also own a 3spd auto 86 Fiero and the first 2 gears on that wind up just like the first 2 gears of a getrag. Yes, I know there are different final drives... But from my experience, bigger wheels + 6spd makes for a better car. In 4th gear at 2000rpm I am doing 45mph where as the getrag would do 40mph. 1st gear is about the same, 3rd might be slightly better but 2nd and 4th are definitely taller and in 6th @ 2000rpm I am doing ~69mph.
If you are putting in a bigger motor, why stick with 215/60/15 tires...?
And personally, I don't care for autos so that's why I gave the opinion that I did.
01-31-2008, 11:52 PM
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As far as tires, I have a staggard setup w/ 17s up front and 18s in the back. The tires are 225/40/17 and 265/35/18.
02-01-2008, 01:55 PM
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I didn't know about the starter issue, but having a 6speed in my car, and 255/55/16 tires and the speedo recalibrated, I can tell you that the transmission is more useful than a getrag.
I now also own a 3spd auto 86 Fiero and the first 2 gears on that wind up just like the first 2 gears of a getrag. Yes, I know there are different final drives... But from my experience, bigger wheels + 6spd makes for a better car. In 4th gear at 2000rpm I am doing 45mph where as the getrag would do 40mph. 1st gear is about the same, 3rd might be slightly better but 2nd and 4th are definitely taller and in 6th @ 2000rpm I am doing ~69mph.
If you are putting in a bigger motor, why stick with 215/60/15 tires...?
And personally, I don't care for autos so that's why I gave the opinion that I did.
I now also own a 3spd auto 86 Fiero and the first 2 gears on that wind up just like the first 2 gears of a getrag. Yes, I know there are different final drives... But from my experience, bigger wheels + 6spd makes for a better car. In 4th gear at 2000rpm I am doing 45mph where as the getrag would do 40mph. 1st gear is about the same, 3rd might be slightly better but 2nd and 4th are definitely taller and in 6th @ 2000rpm I am doing ~69mph.
If you are putting in a bigger motor, why stick with 215/60/15 tires...?
And personally, I don't care for autos so that's why I gave the opinion that I did.
Concerning the gear ratios of the G6 6-speed, 1st gear is 3.76:1 and this trans has a final drive ratio of 3.55:1 (combined=7.31:1). The stock Fiero getrag 282's first gear ratio is 3.50:1 and it's final drive is 3.61:1 (combined=7.11:1). I know this doesn't sound like a big difference, but I have talked to a couple of people who have done the G6 6-speed conversion on their engine swaps and noted 1st gear is pretty much useless because either it is too short or the tires just spin in that gear. I have also done quite a few 3800 Series 2 SC conversions using the 5-speed getrag trans and can tell you 1st gear is almost worthless in that trans.
But that isn't the biggest issue I am concerned with. The G6 6-speed isn't a proven trans behind high-power engines. The 4T65-E is. And when I get asked the question: "Will the 6-speed hold up to my engine the way I like to drive the car?"; what kind of answer can I give the customer? The only one I can think of is that it is an un-tested trans and nobody has been using one long enough behind an engine making a lot of power to be able to know if it is durable or not. I'm sure it's more durable than the getrag 282; but just how much more is still a big question. Personally, I hope the 6-speed is just as durable as the 4T65-E because it would be nice to have a stronger alternative manual transmission to use in these swaps that can hold up to a lot of power. But we aren't going to find out how durable these transmissions are unless someone actually puts it to the test. So you can forget measuring its durability when it is used with a stock 4.9 caddy V8 or carbed 350 SBC only making 210hp; or if the driver of the car is "easy" on it all the time. As wasteful as it sounds, I would really like to see what happens when somebody gets out there with an LS1 or souped-up L67 swap and really starts thrashing on this trans to see what it can take.
Just FYI: for some reason GM quit offering the F40 6-speed transmission in the Pontiac G6 for the 2008 model year. It is still offered but ONLY in the Saab makes and the biggest engine it is used with now is a 2.8L Turbo V6. I am curious as to what the reasoning was behind this decision?
02-01-2008, 02:08 PM
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Don't really think he was flaming or hatin what you both did. An opinion is not flaming, and he didn't call you out on anything in particular. FWIW, he's likely done more on the LS4 than anyone else here, so his "opinion" holds more weight, especially since no one else has stepped in with "dyno proof" and the like.
No, what he was doing was slinging opinions out there about things that were done and used in this swap without offering some facts and evidence to back up his claims. I'm sorry but I just won't accept someone telling me "the stock valve springs are junk" without them offering some proof as to why. Then he went on to make the accusation that my porting job was going to hurt velocity and torque output of the engine "everywhere". Funny how someone can tell that by just looking at a few pictures.
-ryan
02-03-2008, 01:47 PM
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02-04-2008, 12:52 AM
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Has anyone had any success with changing the intake of the LS4 to something else? We tried to see if the LS2 intake would fit and wasn't successful.
Ryan was able to borrow an LS2 intake from Lingenfelter and found that the LS2 intake's throttle body inlet was molded too low and wouldn't clear the oil pressure sending unit; but even if that were removed and the boss for it machined down, measurements indicated the intake would still not clear the DoD electrical plug....
Ryan tried to turn the LS2 intake around to see if it would fit the other way and yes it did -- at least bolt right down on the heads and clear the oil pressure sender and DoD plug... BUT...
Once the water pump housing is installed it wouldn't clear a critical part of the housing -- one of the coolant passages. Here is a comparison picture between the LS2 and LS4 intake...
As you guys know, the LS2 intake has a much larger throttle body opening than the LS4. However, it was unclear if the LS4 would benefit from this large of a throttle body. Ryan thought that the LS4 would benefit from some measure a larger throttle body and throttle body opening but exactly what size would be optimal was unsure. Also, we found that the factory LS4 throttle body and fuel rails would not work with the LS2 intake. So that killed it for me.
We figured at the end of the day, it might be possible to modify an AFTERMARKET cast-aluminum LSx intake to work on the LS4 engine and still have the throttle body facing the correct way. But prices for such intakes ranged from $500 and up, plus the factory LS4's fuel rails or throttle body didn't look like it was compatible. I guess I could have gotten a used intake, but wasn't sure what it would be to mess with the fuel rails. So, I opted to just use the LS4 intake, as I wasn't sure I'd get the amount of gains for the time and extra investment.
Does anyone have any experience of trying other LSx intakes? Would it have been worth the fuss?
Blkcofy
Ryan was able to borrow an LS2 intake from Lingenfelter and found that the LS2 intake's throttle body inlet was molded too low and wouldn't clear the oil pressure sending unit; but even if that were removed and the boss for it machined down, measurements indicated the intake would still not clear the DoD electrical plug....
Ryan tried to turn the LS2 intake around to see if it would fit the other way and yes it did -- at least bolt right down on the heads and clear the oil pressure sender and DoD plug... BUT...
Once the water pump housing is installed it wouldn't clear a critical part of the housing -- one of the coolant passages. Here is a comparison picture between the LS2 and LS4 intake...
As you guys know, the LS2 intake has a much larger throttle body opening than the LS4. However, it was unclear if the LS4 would benefit from this large of a throttle body. Ryan thought that the LS4 would benefit from some measure a larger throttle body and throttle body opening but exactly what size would be optimal was unsure. Also, we found that the factory LS4 throttle body and fuel rails would not work with the LS2 intake. So that killed it for me.
We figured at the end of the day, it might be possible to modify an AFTERMARKET cast-aluminum LSx intake to work on the LS4 engine and still have the throttle body facing the correct way. But prices for such intakes ranged from $500 and up, plus the factory LS4's fuel rails or throttle body didn't look like it was compatible. I guess I could have gotten a used intake, but wasn't sure what it would be to mess with the fuel rails. So, I opted to just use the LS4 intake, as I wasn't sure I'd get the amount of gains for the time and extra investment.
Does anyone have any experience of trying other LSx intakes? Would it have been worth the fuss?
Blkcofy
02-04-2008, 07:04 AM
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A couple of us are starting to make some progress on fitting a LS6 intake.
It is possible to modify the manifold and valley cover to fit the LS6 intake on to the valley cover and clear the oil pressure sending unit, but there won't be any room to fit an intake with a 90mm inlet. See this thread: https://ls1tech.com/forums/ls4-performance/856995-ls6-intake-getting-closer.html
The LS6 intake is supposed to be worth from 15 to 20 hp over the LS1 intake. We can only speculate at this point on what the gains will be over the LS4 intake, but my guess is that it's going to be better than that as the LS1 doesn't have the restriction that the LS4 intake neck has.
Just checking out some of the other threads on the forum, it looks like there are quite a few vehicles making over 400 whp with the 78mm maf/tb + LS6 intake on a 5.7 l engine, so it doesn't look like there is any need to go up to 90mm intake/maf/tb setup on the 5.3.
It is possible to modify the manifold and valley cover to fit the LS6 intake on to the valley cover and clear the oil pressure sending unit, but there won't be any room to fit an intake with a 90mm inlet. See this thread: https://ls1tech.com/forums/ls4-performance/856995-ls6-intake-getting-closer.html
The LS6 intake is supposed to be worth from 15 to 20 hp over the LS1 intake. We can only speculate at this point on what the gains will be over the LS4 intake, but my guess is that it's going to be better than that as the LS1 doesn't have the restriction that the LS4 intake neck has.
Just checking out some of the other threads on the forum, it looks like there are quite a few vehicles making over 400 whp with the 78mm maf/tb + LS6 intake on a 5.7 l engine, so it doesn't look like there is any need to go up to 90mm intake/maf/tb setup on the 5.3.
02-05-2008, 07:06 PM
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I had mentioned before how I've gotten ALOT of knowledge from this site. One topic that comes up often is the reliability of the 4T65-E transmission. I've seen several mentions of shift kits, but still can' discern what work is actually performed, other than the outcome of having more reliable and more firm shifts.
I reached out to Triple Edge Performance to ask exactly what was involved in the performance grade that he had performed on my tranny. He was very helpful to provide the following:
Hi Blkcofy, I really appreciate you mentioning my work on your car and I hope you are pleased with it! I got to see the car last week as I picked up Ryan after he dropped off the car for getting the AC lines made for it and he started it up so I could hear it and check it out and it was pretty sweet! Definately a unique swap and its going to be a head turner for sure! As far as your transmission goes here is what I did to it....... When I rebuild a high performance 4T65E transmission I address some areas that need help to quicken and firm up the shifts. This transmission just as most other GM automatics is made to have smooth comfortable shifts, but this is far from optimal in a performance vehicle especially when making good power. The clutch clearance is way too loose from the factory so I tightened up 2nd and 3rd clutch packs quite a bit. This will help to quicken the shifts without a harsh feeling as the accumulator system doesnt have to max out to make the clutch apply. I also install Transgo shift kits in all of my performance 4T65E transmission. They are not made as a performance kit but give a great foundation for my builds. These kits include new accumulator springs and a few spacers for the 1-2, 2-3, and 3-4 clutch accumulators. They are stiffer springs than factory by far and also help to make the shift quicker but not harsh or drawn out and bangy feeling as some other kits do. In addition to this I open up a few feeds to 2nd and 3rd clutches to get the firmness where I like and I change this for every car depending on mods and driving conditions. There are plenty of guys out there running 400+ HP through these transmissions reliably, though with power levels that high there are a few things that need to be upgraded such as the input shaft and drive chain setup as they are prone to breaking under hard launches with sticky tires. Since you have a newer transmission there arent many other areas that need attention when opening it up. Though models though 2002 and earlier will need a few other parts replaced for durabilty and proper operation. I hope this is what you are looking for info wise and it explains the hows and whys for you. You are welcome to share this on the LS1Tech forum and I hope it helps explain everything that was performed.
David
Triple Edge Performance
TripleEdgePerformance@comcast.net
I hope this helps provide some additional perspective and opinion to what can be done to the 4t65-e trannys, despite all the bad press. David does outstanding work, and from Ryan's reports, everything is crispy!!
I reached out to Triple Edge Performance to ask exactly what was involved in the performance grade that he had performed on my tranny. He was very helpful to provide the following:
Hi Blkcofy, I really appreciate you mentioning my work on your car and I hope you are pleased with it! I got to see the car last week as I picked up Ryan after he dropped off the car for getting the AC lines made for it and he started it up so I could hear it and check it out and it was pretty sweet! Definately a unique swap and its going to be a head turner for sure! As far as your transmission goes here is what I did to it....... When I rebuild a high performance 4T65E transmission I address some areas that need help to quicken and firm up the shifts. This transmission just as most other GM automatics is made to have smooth comfortable shifts, but this is far from optimal in a performance vehicle especially when making good power. The clutch clearance is way too loose from the factory so I tightened up 2nd and 3rd clutch packs quite a bit. This will help to quicken the shifts without a harsh feeling as the accumulator system doesnt have to max out to make the clutch apply. I also install Transgo shift kits in all of my performance 4T65E transmission. They are not made as a performance kit but give a great foundation for my builds. These kits include new accumulator springs and a few spacers for the 1-2, 2-3, and 3-4 clutch accumulators. They are stiffer springs than factory by far and also help to make the shift quicker but not harsh or drawn out and bangy feeling as some other kits do. In addition to this I open up a few feeds to 2nd and 3rd clutches to get the firmness where I like and I change this for every car depending on mods and driving conditions. There are plenty of guys out there running 400+ HP through these transmissions reliably, though with power levels that high there are a few things that need to be upgraded such as the input shaft and drive chain setup as they are prone to breaking under hard launches with sticky tires. Since you have a newer transmission there arent many other areas that need attention when opening it up. Though models though 2002 and earlier will need a few other parts replaced for durabilty and proper operation. I hope this is what you are looking for info wise and it explains the hows and whys for you. You are welcome to share this on the LS1Tech forum and I hope it helps explain everything that was performed.
David
Triple Edge Performance
TripleEdgePerformance@comcast.net
I hope this helps provide some additional perspective and opinion to what can be done to the 4t65-e trannys, despite all the bad press. David does outstanding work, and from Ryan's reports, everything is crispy!!
Last edited by BLKCOFY; 02-05-2008 at 07:16 PM.
02-08-2008, 04:51 PM
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Ryan is nearing final stages on the swap. Thought I'd continue to share status. Bad weather, time the car spent at the alignment and a/c shops, other repairs the car needed (heater core), waiting on parts to come in, etc. have kept things at a slower pace than Ryan had planned, but I'm in no hurry...
The fun stage starts when he gets to being able to put it thru its road trials, which is difficult to do with the bad weather we've been having. But here's where he is with the build. Much of this is Fiero specific, but may be interesting for those who are looking to swap the LS4 into another car.
SPEEDO:
As Ryan initially suspected, he was not able to use the VSS output to radio the ECM has because it wasn't a signal he could get the Fiero speedo to recognize. He was able to get the Fiero speedo to recognize the VSS signal coming out of the TCM going into the ECM, but it was reading about 6.5x too fast. Ryan contacted Dakota Digital and ordered their SGI-5 speedo signal interface module. This unit is fully programmable on-the-fly and ended up working great for this application. He did have to run the Fiero speedo off the SGI-5's "2000ppm oc" output (usually used for older ECMs and cruise controls) in order for it to work tho. Also had to run the output signal from the SGI-5 thru the Fiero speedo conversion circuit Ryan shows on his website: http://dtcc.cz28.com/fiero/fmods.htm
TACH:
The ECM has a tach output. At first, Ryan was unable to get the Fiero's tach to recognize this signal; but then he realized it is used to seeing a signal that has a 12v bias (because it is coming off the ignition coil and gets pulled to ground when the ign module commands the coil to fire). Appearantly, the ECM only puts out a ground pulse with no compatible positive power bias, and the Fiero's tach couldn't recognize this. Ryan got it to work by running a wire from an IGN 12v + source thru a 22k ohm resistor, then tieing that into the existing tach wire. With this done the tach was registering engine RPM, but appeared to be 1/3 too slow reading vs. actual engine RPM. According to Ryan, on previous swaps, he had the reverse problem when he wanted to get a 4cyl tach to work with a V6. With that issue all he did was to replace the calibration capacitor with one that had a lower uF rating than stock (stock = 0.009uF and he replaced it with 0.006uF to correct the reading). Turns out this stock V6 tach had the same 0.009uF capacitor in the same location on the curcuit board as that 4cyl unit had. Ryan had a tough time finding the correct capacitor he needed so he ran two in a parallel curcuit to get the 0.0114uF rating he needed and it seems to be dead on with the scan tool says the actual engine RPM is doing. A picture showing the location of the capacitor in question can be seen here: http://dtcc.cz28.com/fiero/tach.jpg
DIC MOUNTING:
The stock Fiero dash has no real place to mount the DIC unit, but Ryan cleverly took the liberty of fab'ing up a mounting bracket, and put the DIC up on the dash (using existing OE dash trim mounting screws) temporarily. I plan on either fiberglassing a holder for the DIC or I'm likely to try to retro-fit the Grand Prix GXP dash sometime in the future, but until then Ryan's solution works for me as I'm able to use (and see) the DIC. Below is a picture of where he put the DIC and you can also see the new MOMO steering wheel and paddle shifter setup...
DRIVING IMPRESSIONS (as quoted by Ryan):
"I still have some tuning to do. For one thing the DoD seems to want to kick in at speeds as slow as 25mph and during light-moderate accelleration which is kind of annoying. There is a constant in HP Tuners that is supposed to allow me to set the MPH qualifier for DoD to kick in but I've tried many different settings here and nothing has had an effect so for. So I am going to contact HP Tuners and see what can be done. I did find min/max RPM qualifiers for DoD operation and those do work, so I can at least somewhat work around this for now in case HP Tuners can't resolve the issue.
Transmission shift points and firmness still need some tweaking but it's getting close. As with many aspects of tuning, things like this can only be ironed out on the road and require some driving time to get right. A dyno is pretty much useless for this aspect of the tuning.
Idle, part throttle cruising, and light-moderate accelleration fuel and spark seem to be very close to where they need to be. Haven't been able to do many WOT blasts around here with the slick conditions. But those I have been able to do showed the engine is right at home in a (roughly) 700lb less body than it is used to. This engine has more than enough power to spin the tires upon request at low speeds or from a dead stop and it has pretty long legs for the big end. I don't think blkcofy is going to be disappointed. The exhaust note this engine makes at full song is possibily the best I've heard coming from an exhaust system running only cats and resonated tips (thanks to the LSx's revised firing order vs. conventional SBC); despite the fact it is a tad on the loud side. The interior drone on the highway isn't any worse (might even be less so) than what 3800's put out with the same exhaust system. To be quite honest this thing really doesn't make its presence known until you get into it a bit. But when you do, it will definately turn heads."
That's pretty much it so far. Ryan is contacting the chassis dyno shop tomorrow to get rates and schedule info so he can get this thing dyno'ed. It's MAD EXPENSIVE! I'm shocked with what their able to get away with charging. But I'm hoping for some dry weather so Ryan can get some more seat time to tweak the programming in the ECM and TCM.
The fun stage starts when he gets to being able to put it thru its road trials, which is difficult to do with the bad weather we've been having. But here's where he is with the build. Much of this is Fiero specific, but may be interesting for those who are looking to swap the LS4 into another car. SPEEDO:
As Ryan initially suspected, he was not able to use the VSS output to radio the ECM has because it wasn't a signal he could get the Fiero speedo to recognize. He was able to get the Fiero speedo to recognize the VSS signal coming out of the TCM going into the ECM, but it was reading about 6.5x too fast. Ryan contacted Dakota Digital and ordered their SGI-5 speedo signal interface module. This unit is fully programmable on-the-fly and ended up working great for this application. He did have to run the Fiero speedo off the SGI-5's "2000ppm oc" output (usually used for older ECMs and cruise controls) in order for it to work tho. Also had to run the output signal from the SGI-5 thru the Fiero speedo conversion circuit Ryan shows on his website: http://dtcc.cz28.com/fiero/fmods.htm
TACH:
The ECM has a tach output. At first, Ryan was unable to get the Fiero's tach to recognize this signal; but then he realized it is used to seeing a signal that has a 12v bias (because it is coming off the ignition coil and gets pulled to ground when the ign module commands the coil to fire). Appearantly, the ECM only puts out a ground pulse with no compatible positive power bias, and the Fiero's tach couldn't recognize this. Ryan got it to work by running a wire from an IGN 12v + source thru a 22k ohm resistor, then tieing that into the existing tach wire. With this done the tach was registering engine RPM, but appeared to be 1/3 too slow reading vs. actual engine RPM. According to Ryan, on previous swaps, he had the reverse problem when he wanted to get a 4cyl tach to work with a V6. With that issue all he did was to replace the calibration capacitor with one that had a lower uF rating than stock (stock = 0.009uF and he replaced it with 0.006uF to correct the reading). Turns out this stock V6 tach had the same 0.009uF capacitor in the same location on the curcuit board as that 4cyl unit had. Ryan had a tough time finding the correct capacitor he needed so he ran two in a parallel curcuit to get the 0.0114uF rating he needed and it seems to be dead on with the scan tool says the actual engine RPM is doing. A picture showing the location of the capacitor in question can be seen here: http://dtcc.cz28.com/fiero/tach.jpg
DIC MOUNTING:
The stock Fiero dash has no real place to mount the DIC unit, but Ryan cleverly took the liberty of fab'ing up a mounting bracket, and put the DIC up on the dash (using existing OE dash trim mounting screws) temporarily. I plan on either fiberglassing a holder for the DIC or I'm likely to try to retro-fit the Grand Prix GXP dash sometime in the future, but until then Ryan's solution works for me as I'm able to use (and see) the DIC. Below is a picture of where he put the DIC and you can also see the new MOMO steering wheel and paddle shifter setup...
DRIVING IMPRESSIONS (as quoted by Ryan):
"I still have some tuning to do. For one thing the DoD seems to want to kick in at speeds as slow as 25mph and during light-moderate accelleration which is kind of annoying. There is a constant in HP Tuners that is supposed to allow me to set the MPH qualifier for DoD to kick in but I've tried many different settings here and nothing has had an effect so for. So I am going to contact HP Tuners and see what can be done. I did find min/max RPM qualifiers for DoD operation and those do work, so I can at least somewhat work around this for now in case HP Tuners can't resolve the issue.
Transmission shift points and firmness still need some tweaking but it's getting close. As with many aspects of tuning, things like this can only be ironed out on the road and require some driving time to get right. A dyno is pretty much useless for this aspect of the tuning.
Idle, part throttle cruising, and light-moderate accelleration fuel and spark seem to be very close to where they need to be. Haven't been able to do many WOT blasts around here with the slick conditions. But those I have been able to do showed the engine is right at home in a (roughly) 700lb less body than it is used to. This engine has more than enough power to spin the tires upon request at low speeds or from a dead stop and it has pretty long legs for the big end. I don't think blkcofy is going to be disappointed. The exhaust note this engine makes at full song is possibily the best I've heard coming from an exhaust system running only cats and resonated tips (thanks to the LSx's revised firing order vs. conventional SBC); despite the fact it is a tad on the loud side. The interior drone on the highway isn't any worse (might even be less so) than what 3800's put out with the same exhaust system. To be quite honest this thing really doesn't make its presence known until you get into it a bit. But when you do, it will definately turn heads."
That's pretty much it so far. Ryan is contacting the chassis dyno shop tomorrow to get rates and schedule info so he can get this thing dyno'ed. It's MAD EXPENSIVE! I'm shocked with what their able to get away with charging. But I'm hoping for some dry weather so Ryan can get some more seat time to tweak the programming in the ECM and TCM.
02-13-2008, 11:36 PM
#38
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Right now I'm trying to see if the Turbo kit that was installed by one of your members will fit in the Fiero. Based on his last dyno, he was getting 467 hp at the wheels!! Good googly-goo!! http://www.youtube.com/watch?v=taCvjnLwYHY
02-14-2008, 02:31 PM
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[FONT="Franklin Gothic Medium"] The 2.8L V6 Fiero Engine weighed 365 lbs compared to the LS4 (block, internals, and heads) of 339 lbs. But where I gain back any weight loss is from the 4T65e transmission which is 241 lbs compared to about 140 lbs for the Getrag 282 that came out of it. So I probably gained about 100 lbs based on the swap...BUT went from 140hp to hopefully 340hp when all is said and done. Only the dyno will tell how much power will be at the wheels. I suspect that the total weight for the car will be close to 2850 lbs.
02-18-2008, 09:59 PM
#40
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STS swap... I remember an article a long time ago, not sure what mag, but a guy swapped a Caddy STS 300hp Northstar and his Fiero was in the 12s in the quarter.