427ci, FRH ported TFS GenX LS3, EPS cam, Vic. Jr.
03-30-2015, 11:06 PM
#1
427ci, FRH ported TFS GenX LS3, EPS cam, Vic. Jr. Recently I had the misfortune to drop a valve in my LS2-based 402ci with only 3800 miles on it. At first, I was going to just rebuild it as a 402, but as these things tend to do, it escalated into an upgrade. I spoke to a lot of people who helped contribute to this build, and I'm very happy with the final results.
My goals for this were not a max dyno number. Instead, this is a pro-touring 71 Firebird which is driven on the street a lot. I attend autocross events and do track days, so I wanted to maximize my mid-range powerband as much as I could. I have to drive 200 miles each way to the big events I attend each year, so I wanted a good 2200 - 2400 rpm cruise manners as well.
The one thing I was not willing to change during this rebuild was the intake manifold: the L92 version of the Victor Jr. I have a lot invested in that setup to keep my functional shaker on this car. That also dictated staying with the LS3 intake ports.
So with that, here are the highlights of my combination:
Since Texas Speed is local to me, I worked with them on the long block build. What started out as a rebuild of my LS2/402 turned into a bigger project of new block and heads and cam. There were a few delays along the way, but those ended up allowing me to add even bigger and better parts (ie: block, heads, cam) along the way. Frankenstein ordered up the TFS castings and did a nice custom port for me to match my expectations (not an all-out port, but one tailored to optimize my mid-range requirements). And Geoff at EPS worked with me to come up with a cam that would give me the same driving characteristics of the cam I already had (a previous EPS cam) while adding for the extra CI I added going to the 427".
For posterity sake, here are a couple of pictures.
(hard to get the intake port)
Long block coming back from TSP:
About ready to drop in:
I have been scrambling to get the engine pulled together because 2 of my 3 biggest events of the year were happening here in mid-March, and the dropped valve happened in January. It took a big last minute push, but I managed to get everything collected, assembled, and installed. And by that I mean I was bolting on the last pieces about 7:00 the night before I was making my first 500 mile roadtrip to run an autocross all weekend!
I had never had the chance to dyno the previous 402 combination, as a matter of fact, I was doing so when the valve dropped (the first pull no less, so I never even got a number). I wanted to get this setup dynoed as soon as I could after breaking it in, and before my second event which was going to be harder on the motor (track day). So last week I made the 2 hour drive to Bryan, Tx where I had LSX Power Tuning do his thing. We spent about 3 hours on the car, making about 15 dyno pulls. Somewhat surprisingly, the tune I brought to him was pretty close, as the Holley does a good job of running in closed loop (as long as your targets are right, and in my case, I was within 9HP of the max number). Laurence optimized all the base tables and then we took it for about an hour street drive where he worked on the part throttle conditions. The car runs really well, I'm happy with his work.
Finally, the results. Here ya go:
This was done on a Dynocom load-bearing dyno, so I don't have any experience as to how it might compare to any other dyno. I do know that we had good conditions that day, so the SAE correction cost me a lot. My best run actually put down 568 HP and was corrected down to the 541.
What I love about this result is the flat torque curve! I wasn't really certain if I could attain this with the single-plane. But we sure did!
If it matters, the rest of the drivetrain is a T56 Magnum (runs in 4th gear) feeding a Ford 9" with 3.89:1 gears and spinning a set of 18" wheels/tires (35# of pressure). We did all of the runs with the shaker attached except for 1, and surprisingly it only picked up 2 HP by removing it. I don't count that since it's not how I will ever drive the car.
As I look at the plot, I think there might be a little more in the engine up top. I am close to if not at the limit of my fuel pump in the higher RPM range. I haven't looked at the duty cycle on the Holley, but I get my interior gauge warning light going off when I go full throttle at high RPM. That said, the graph doesn't show the AFR going lean, so I think the Holley is able to keep the demand satisfied, so that's something I want to investigate further. I just wonder if it's starting to roll over around 5500 when it might have more to give.
We were trying to pull up to 7k rpm, but the dyno wasn't capturing the end of the runs exactly right, so I don't have a plot to show any higher than 6500. But the peaks were right there, so there's not much else to show.
A few things I wish I had had the chance to do differently... I would have liked to have tried a set of short-travel lifters. In my last minute scramble, it was something I tried to get but wasn't able to. I would have liked to have stepped up to a set of LS7 heads, but again, the intake was set in stone. And I would like to run a dry sump on this thing given my use, but my accessory drive wouldn't allow for one, so I added an Accusump to my car instead.
I would highly recommend any of the vendors that were a part of supplying parts for this build. They were helpful and generous with their time, and I feel that I really pulled together a great combination for my goals with their help.
My goals for this were not a max dyno number. Instead, this is a pro-touring 71 Firebird which is driven on the street a lot. I attend autocross events and do track days, so I wanted to maximize my mid-range powerband as much as I could. I have to drive 200 miles each way to the big events I attend each year, so I wanted a good 2200 - 2400 rpm cruise manners as well.
The one thing I was not willing to change during this rebuild was the intake manifold: the L92 version of the Victor Jr. I have a lot invested in that setup to keep my functional shaker on this car. That also dictated staying with the LS3 intake ports.
So with that, here are the highlights of my combination:
- LS7 block with 4.127" bore (machine work done by TSP)
- Callies DragonSlayer 4.000" stroke crank with 2.000" rod journals
- Callies Compstar 6.125" rods
- TSP/Wiseco 4.127" pistons with 4cc valve reliefs
- TFS GenX LS3 heads, custom ported by Frankenstein Racing Heads
- 2.20" FRH lightweight intake valves
- 1.60" Stainless exhaust valves
- BTR Platinum .660" springs and titanium retainers
- Cometic MLS head gaskets, 0.051" targeting 12:1 compression ratio
- Cam speced by Geoff at EPS, ground by Cam Motion (238/248, .629/.604, 114+5)
- Morel 5315 lifters
- Stock LS3 rockers with Harland Sharpe trunion upgrade
- Edelbrock Victor Jr. L92, ported by Frankenstein Racing Heads (plenum and port matched)
- Deatschwerks 42# Injectors
- Holley HP EFI ECU
- Custom set of tri-y headers with 1.875" primaries to 2.25" then 3" collectors
- Monster Clutch's LT1-S twin-disk clutch/flywheel
Since Texas Speed is local to me, I worked with them on the long block build. What started out as a rebuild of my LS2/402 turned into a bigger project of new block and heads and cam. There were a few delays along the way, but those ended up allowing me to add even bigger and better parts (ie: block, heads, cam) along the way. Frankenstein ordered up the TFS castings and did a nice custom port for me to match my expectations (not an all-out port, but one tailored to optimize my mid-range requirements). And Geoff at EPS worked with me to come up with a cam that would give me the same driving characteristics of the cam I already had (a previous EPS cam) while adding for the extra CI I added going to the 427".
For posterity sake, here are a couple of pictures.
(hard to get the intake port)
Long block coming back from TSP:
About ready to drop in:
I have been scrambling to get the engine pulled together because 2 of my 3 biggest events of the year were happening here in mid-March, and the dropped valve happened in January. It took a big last minute push, but I managed to get everything collected, assembled, and installed. And by that I mean I was bolting on the last pieces about 7:00 the night before I was making my first 500 mile roadtrip to run an autocross all weekend!
I had never had the chance to dyno the previous 402 combination, as a matter of fact, I was doing so when the valve dropped (the first pull no less, so I never even got a number). I wanted to get this setup dynoed as soon as I could after breaking it in, and before my second event which was going to be harder on the motor (track day). So last week I made the 2 hour drive to Bryan, Tx where I had LSX Power Tuning do his thing. We spent about 3 hours on the car, making about 15 dyno pulls. Somewhat surprisingly, the tune I brought to him was pretty close, as the Holley does a good job of running in closed loop (as long as your targets are right, and in my case, I was within 9HP of the max number). Laurence optimized all the base tables and then we took it for about an hour street drive where he worked on the part throttle conditions. The car runs really well, I'm happy with his work.
Finally, the results. Here ya go:
This was done on a Dynocom load-bearing dyno, so I don't have any experience as to how it might compare to any other dyno. I do know that we had good conditions that day, so the SAE correction cost me a lot. My best run actually put down 568 HP and was corrected down to the 541.
What I love about this result is the flat torque curve! I wasn't really certain if I could attain this with the single-plane. But we sure did!
If it matters, the rest of the drivetrain is a T56 Magnum (runs in 4th gear) feeding a Ford 9" with 3.89:1 gears and spinning a set of 18" wheels/tires (35# of pressure). We did all of the runs with the shaker attached except for 1, and surprisingly it only picked up 2 HP by removing it. I don't count that since it's not how I will ever drive the car.
As I look at the plot, I think there might be a little more in the engine up top. I am close to if not at the limit of my fuel pump in the higher RPM range. I haven't looked at the duty cycle on the Holley, but I get my interior gauge warning light going off when I go full throttle at high RPM. That said, the graph doesn't show the AFR going lean, so I think the Holley is able to keep the demand satisfied, so that's something I want to investigate further. I just wonder if it's starting to roll over around 5500 when it might have more to give.
We were trying to pull up to 7k rpm, but the dyno wasn't capturing the end of the runs exactly right, so I don't have a plot to show any higher than 6500. But the peaks were right there, so there's not much else to show.
A few things I wish I had had the chance to do differently... I would have liked to have tried a set of short-travel lifters. In my last minute scramble, it was something I tried to get but wasn't able to. I would have liked to have stepped up to a set of LS7 heads, but again, the intake was set in stone. And I would like to run a dry sump on this thing given my use, but my accessory drive wouldn't allow for one, so I added an Accusump to my car instead.
I would highly recommend any of the vendors that were a part of supplying parts for this build. They were helpful and generous with their time, and I feel that I really pulled together a great combination for my goals with their help.
I'm enjoying following your progress as well! 
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04-02-2015, 09:24 PM
#8
Correct, Chris purchased the 'porter' heads and created his own custom port for the heads. He has a couple of different port styles depending on the displacement and desired application. He combined a couple of aspects from the different designs to create my port.
04-03-2015, 06:05 PM
#10
Yes, they are more expensive than the out of the box TFS heads, but my assumption is that the component quality is higher. I also got a custom port to match my desired combination. It will take longer to get them than just calling up Summit and ordering a set, but for me it was worth it.
04-04-2015, 07:19 AM
#11
Nice 
I've been reading your build thread for the last two days & forgot about this thread while doing so. I'm on post #35 & oh snap I was going to check my dyno runs & what is happening @ 5500rpm. Awesome build thread btw.
I also have a set of Chris Frank heads that started as a rough casting cnc port TF 235's. Its an LS3 stroker, 416ci & a Fast 102 & NW 102, AR 1 7/8 headers & a full 3" catted exhaust. My exhaust isn't near as fancy as yours, my god man your exhaust is art work
Your motor is making more power @ 5500rpm which is what would be expected, realizing you cannot compare dyno's espically different manufacturers. It's what happens after 5500 that raised my curiosity, you are flat lining. I'm going to assume your AFR is still as commanded @ 5500rpm & not showing signs of going lean as well the timing curve is good & possibly starting a slight increase. Not knowing anything about your intake setup, where is the peak rpm expected? Is there a possibility the dyno is not reporting correctly @ that power level? I've experienced that problem with a dyno, so it is possible.
I've been reading your build thread for the last two days & forgot about this thread while doing so. I'm on post #35 & oh snap I was going to check my dyno runs & what is happening @ 5500rpm. Awesome build thread btw.I also have a set of Chris Frank heads that started as a rough casting cnc port TF 235's. Its an LS3 stroker, 416ci & a Fast 102 & NW 102, AR 1 7/8 headers & a full 3" catted exhaust. My exhaust isn't near as fancy as yours, my god man your exhaust is art work
Your motor is making more power @ 5500rpm which is what would be expected, realizing you cannot compare dyno's espically different manufacturers. It's what happens after 5500 that raised my curiosity, you are flat lining. I'm going to assume your AFR is still as commanded @ 5500rpm & not showing signs of going lean as well the timing curve is good & possibly starting a slight increase. Not knowing anything about your intake setup, where is the peak rpm expected? Is there a possibility the dyno is not reporting correctly @ that power level? I've experienced that problem with a dyno, so it is possible.
04-04-2015, 11:02 AM
#12
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Great Job, Well Done!
Excellent torque Plateau! 400 @ 3000RPM Especially with a single
plane intake. Great Heads and a Medium sized cam Great Results!
Must be a Blast to Drive!
Excellent torque Plateau! 400 @ 3000RPM Especially with a single
plane intake. Great Heads and a Medium sized cam Great Results!
Must be a Blast to Drive!
04-05-2015, 11:14 PM
#13
Thanx!
Funny you say that. You wouldn't believe how much time (and money!) I have tied up in that exhaust... We've built most of it twice, cut and relocated some of the header tubes for clearance, and re-ceramic coated the front half of it. But I finally got the ground clearance I wanted without giving up any flow. And then after getting it all just right, I was leaving a track day on a bad road and bottomed out the car and ended up with this:
I think the same thing, and thus I have ordered a new fuel pump/module from a 5th Gen ZL1 to replace the standard 5th Gen Camaro unit I currently have. The current one is supposedly good to about 650HP, while the ZL1 is supposedly good to about 800. My next step up would be to a CTS-V pump/module, but I don't need that level of flow, and it would just create extra heat and aeration in the pump.
The AFR looks like it is as expected, but I'm wondering if by losing pressure it's causing some other side effect. I will probably take it to a local dyno just to confirm what happens after changing the pump/module. I expect some change, but it will be interesting to see what happens. During the tuning session, we didn't find that adding timing helped above 5000 rpm, but I don't recall what the curve looks like at the moment.
This dyno does a lot of FI cars, so I'm confident that I'm not overpowering it. The intake / heads / cam combination should peak around 6300-6400, which is about what the curve looks like it would do. And that's around where it's reported too, but like you observed, I think it flattened out a bit.
The new ZL1 module arrived today (yes, Sunday, Amazon Prime rocks), and I hope to have it installed by the end of the week. Maybe I can arrange to dyno it the following week before my next track day.
The new ZL1 module arrived today (yes, Sunday, Amazon Prime rocks), and I hope to have it installed by the end of the week. Maybe I can arrange to dyno it the following week before my next track day.
04-05-2015, 11:18 PM
#14
This science project really turned out well. I did a lot of research here on LS1Tech and a few other forums, and I was able to 'catch up' with the latest trends on these engines. I appreciate all that I learned from the contributions of others, so perhaps this information on my combination will help someone else down the line...
04-11-2015, 12:29 PM
#17
CArbuf,
How loud is yor exhuast with those Borla muffs?
thanks,
Jim
How loud is yor exhuast with those Borla muffs?
thanks,
Jim
04-12-2015, 08:26 PM
#20
I run 93. I've never checked into my local availability of E85, but since I drive this car a pretty good amount, I'm not sure that would make sense.
I'm running a Wegner aftermarket front drive kit. It's one they don't make anymore, in large part because it didn't work with the dry sumps very well, and also because they use different components (alternator specifically) which allows them to package things differently.
I'm running a Wegner aftermarket front drive kit. It's one they don't make anymore, in large part because it didn't work with the dry sumps very well, and also because they use different components (alternator specifically) which allows them to package things differently.