My car is a turd! - maybe not
Thread Starter
Joined: Nov 2009
Posts: 1,621
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From: THORNTON, PA (NEAR PHILLY)
My car is a turd! - maybe not So finally went to the track and got a couple of passes in before I got asked to leave for no cage.
1st run was 1.7/7.16/101.5/128.8 12ps, 12* of timing
2nd run was 2.0/7.35/104.88/11.0/132.6, 12psi, timing to 16*, disconnect meth inj, blew tires off.
Looked at the datalogs, everything looks good except I normally burn about ~460lb/hr of fuel farting around town. I could only burn around 370 lb/hr here. I had 1/4 of 93 octane, and I mixed in 5 gal of 110. I noticed right off the car idled bad. Could the race gas of did me in here??? Car ran otherwise really good and pulled nice and clean to the 6000 rpm shift points.
This is disappointing b/c the 5.3 I took out with a cheapy converter and 14psi ran 1.8/10.8/134. WTF????
I also think the converter is WAY too tight. With the old converter I used the most fuel in 3rd gear, now it 2nd gear. I'm getting an 1100-1200 drop from the 2-3rd shift. But with this converter I was still able to burn fuel, just couldnt do it tonight.
1st run was 1.7/7.16/101.5/128.8 12ps, 12* of timing
2nd run was 2.0/7.35/104.88/11.0/132.6, 12psi, timing to 16*, disconnect meth inj, blew tires off.
Looked at the datalogs, everything looks good except I normally burn about ~460lb/hr of fuel farting around town. I could only burn around 370 lb/hr here. I had 1/4 of 93 octane, and I mixed in 5 gal of 110. I noticed right off the car idled bad. Could the race gas of did me in here??? Car ran otherwise really good and pulled nice and clean to the 6000 rpm shift points.
This is disappointing b/c the 5.3 I took out with a cheapy converter and 14psi ran 1.8/10.8/134. WTF????
I also think the converter is WAY too tight. With the old converter I used the most fuel in 3rd gear, now it 2nd gear. I'm getting an 1100-1200 drop from the 2-3rd shift. But with this converter I was still able to burn fuel, just couldnt do it tonight.
Last edited by 69-chvl; Apr 17, 2015 at 08:40 PM.
I kind of had the same issue and put a heat gun on the header tubes and found out I had been running on 7 cylinders the whole time. Idled and drove great on 7 cylinders, you'd never know the difference other than the track numbers.
I had a similar scenario this past weekend. The car felt strong on the street, but when we were finally able to get it down the track it went a 2.0/7.45/102. We checked it with a heat gun and found a cool cylinder. We pulled the plug and it was all black, the wires were old and maybe bad. But the other night I did a compression test, and it was 120-5 lbs on all cylinders. We're going to degree the cam tonight and find out it it's retarded several degrees.
Thread Starter
Joined: Nov 2009
Posts: 1,621
Likes: 31
From: THORNTON, PA (NEAR PHILLY)
I did a compression test the other day and was at 200lbs all the way around. I'll check though to make sure there all firing.
But - I'm missing about 90lb/hr of fuel consumption...that's like 150hp by my calculation at .6 BSFC.
But - I'm missing about 90lb/hr of fuel consumption...that's like 150hp by my calculation at .6 BSFC.
So finally went to the track and got a couple of passes in before I got asked to leave for no cage.
1st run was 1.7/7.16/101.5/128.8 12ps, 12* of timing
2nd run was 2.0/7.35/104.88/11.0/132.6, 12psi, timing to 16*, disconnect meth inj, blew tires off.
Looked at the datalogs, everything looks good except I normally burn about ~460lb/hr of fuel farting around town. I could only burn around 370 lb/hr here. I had 1/4 of 93 octane, and I mixed in 5 gal of 110. I noticed right off the car idled bad. Could the race gas of did me in here??? Car ran otherwise really good and pulled nice and clean to the 6000 rpm shift points.
This is disappointing b/c the 5.3 I took out with a cheapy converter and 14psi ran 1.8/10.8/134. WTF????
I also think the converter is WAY too tight. With the old converter I used the most fuel in 3rd gear, now it 2nd gear. I'm getting an 1100-1200 drop from the 2-3rd shift. But with this converter I was still able to burn fuel, just couldnt do it tonight.
1st run was 1.7/7.16/101.5/128.8 12ps, 12* of timing
2nd run was 2.0/7.35/104.88/11.0/132.6, 12psi, timing to 16*, disconnect meth inj, blew tires off.
Looked at the datalogs, everything looks good except I normally burn about ~460lb/hr of fuel farting around town. I could only burn around 370 lb/hr here. I had 1/4 of 93 octane, and I mixed in 5 gal of 110. I noticed right off the car idled bad. Could the race gas of did me in here??? Car ran otherwise really good and pulled nice and clean to the 6000 rpm shift points.
This is disappointing b/c the 5.3 I took out with a cheapy converter and 14psi ran 1.8/10.8/134. WTF????
I also think the converter is WAY too tight. With the old converter I used the most fuel in 3rd gear, now it 2nd gear. I'm getting an 1100-1200 drop from the 2-3rd shift. But with this converter I was still able to burn fuel, just couldnt do it tonight.
Basically 133 on 12lbs. (with a poor tune) Exh. could make a big diff too.
5.3 went 134 at 14lbs.
First problem I see is you added more octane and didn't up your boost. That combined with meth inj. and low timing was killing power. Make a pass with your DD at the track, then fill it up with C16 and make a pass. It will run much slower.
You went about your tuning backwards IMO. You added a bunch of octane and went right to timing. Timing is that last thing I adjust on a tune.
IMO leave your timing as is. Setup your meth inj to start spraying at 12lbs. Turn the boost up to 17 and I bet it's a whole new car. More power will add to converter slip and cause less of a drop on your shifts.
Quit babying it and turn up that boost ****!
Then go back and add timing. You'll need more than 2 passes, I'd do 1/8th mile until you get it worked out.
Last edited by Forcefed86; Apr 16, 2015 at 01:30 PM.
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Thread Starter
Joined: Nov 2009
Posts: 1,621
Likes: 31
From: THORNTON, PA (NEAR PHILLY)
Sounds about right to me, I wouldn't be too discouraged. Look at MPH to judge power, not ET.
Basically 133 on 12lbs. (with a poor tune) Exh. could make a big diff too.
5.3 went 134 at 14lbs.
First problem I see is you added more octane and didn't up your boost. That combined with meth inj. and low timing was killing power. Make a pass with your DD at the track, then fill it up with C16 and make a pass. It will run much slower.
You went about your tuning backwards IMO. You added a bunch of octane and went right to timing. Timing is that last thing I adjust on a tune.
IMO leave your timing as is. Setup your meth inj to start spraying at 12lbs. Turn the boost up to 17 and I bet it's a whole new car. More power will add to converter slip and cause less of a drop on your shifts.
Quit babying it and turn up that boost ****!
Then go back and add timing. You'll need more than 2 passes, I'd do 1/8th mile until you get it worked out.
Basically 133 on 12lbs. (with a poor tune) Exh. could make a big diff too.
5.3 went 134 at 14lbs.
First problem I see is you added more octane and didn't up your boost. That combined with meth inj. and low timing was killing power. Make a pass with your DD at the track, then fill it up with C16 and make a pass. It will run much slower.
You went about your tuning backwards IMO. You added a bunch of octane and went right to timing. Timing is that last thing I adjust on a tune.
IMO leave your timing as is. Setup your meth inj to start spraying at 12lbs. Turn the boost up to 17 and I bet it's a whole new car. More power will add to converter slip and cause less of a drop on your shifts.
Quit babying it and turn up that boost ****!
Then go back and add timing. You'll need more than 2 passes, I'd do 1/8th mile until you get it worked out.
I hear ya though, I ran close to the 5.3 with less boost, so that's a good thing. Looking through all the datalogs, I was actually closer to 11psi (11.3-ish). Seems like my manual boost controller is subject to weather conditions b/c all winter I was getting 12psi, and now that its warmer out I lost a little boost. AND, the 5.3 was actually 16psi for those track runs...for some reason I thought those runs were 14psi. There's my missing 100+hp LOL!
Do you guys think a 1200 rpm drop from 2-3rd is high? My other converter was much less - like maybe 700. Slip on this converter at 11psi was 5.5%.
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Verdad Gallardo Do you think the octane could of made a big difference in terms of performance (or lack of)? I had one 1/8 only run with 16psi, and it still only pulled 101 mph but I spun off the line and had to back off/on again.
I hear ya though, I ran close to the 5.3 with less boost, so that's a good thing. Looking through all the datalogs, I was actually closer to 11psi (11.3-ish). Seems like my manual boost controller is subject to weather conditions b/c all winter I was getting 12psi, and now that its warmer out I lost a little boost. AND, the 5.3 was actually 16psi for those track runs...for some reason I thought those runs were 14psi. There's my missing 100+hp LOL!
Do you guys think a 1200 rpm drop from 2-3rd is high? My other converter was much less - like maybe 700. Slip on this converter at 11psi was 5.5%.
I hear ya though, I ran close to the 5.3 with less boost, so that's a good thing. Looking through all the datalogs, I was actually closer to 11psi (11.3-ish). Seems like my manual boost controller is subject to weather conditions b/c all winter I was getting 12psi, and now that its warmer out I lost a little boost. AND, the 5.3 was actually 16psi for those track runs...for some reason I thought those runs were 14psi. There's my missing 100+hp LOL!
Do you guys think a 1200 rpm drop from 2-3rd is high? My other converter was much less - like maybe 700. Slip on this converter at 11psi was 5.5%.
I’m not saying 12* of timing is ideal. I’m sure at 11lbs you should be around 16* (or more on that fuel mixture.) Need to go 1 degree at a time and see what the MPH does. I wouldn’t suggest 4* jumps… ever. Mixing fuel is also inconsistent. If you make a habit of it, leave yourself a big margin of error with the tune.
A 1200 drop isn’t bad, 900-1000 would be better IMO. What are you shifting at? Turn it up 15+lbs (maybe shift a bit higher) and it may be perfect.
Thread Starter
Joined: Nov 2009
Posts: 1,621
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From: THORNTON, PA (NEAR PHILLY)
I think it could. 11lbs doesn’t require that much octane. Boost speeds up the burn/flame front, octane slows it down. Advancing timing starts that flame front sooner. (probably why you saw such drastic improvements adding 4*) Additional timing isn’t always good thing though. You’re lighting off the mixture before TDC which is pushing down on the piston while it’s still moving up. (wasted work, hard on parts) You want as little advance as necessary. So adding a ton of octane when it’s not needed and then advancing timing to compensate is not the best way to make power.
I’m not saying 12* of timing is ideal. I’m sure at 11lbs you should be around 16* (or more on that fuel mixture.) Need to go 1 degree at a time and see what the MPH does. I wouldn’t suggest 4* jumps… ever. Mixing fuel is also inconsistent. If you make a habit of it, leave yourself a big margin of error with the tune.
A 1200 drop isn’t bad, 900-1000 would be better IMO. What are you shifting at? Turn it up 15+lbs (maybe shift a bit higher) and it may be perfect.
I’m not saying 12* of timing is ideal. I’m sure at 11lbs you should be around 16* (or more on that fuel mixture.) Need to go 1 degree at a time and see what the MPH does. I wouldn’t suggest 4* jumps… ever. Mixing fuel is also inconsistent. If you make a habit of it, leave yourself a big margin of error with the tune.
A 1200 drop isn’t bad, 900-1000 would be better IMO. What are you shifting at? Turn it up 15+lbs (maybe shift a bit higher) and it may be perfect.
I've been trying to shift at 6000-6100 rpms as I dont think the LS6 cam needs to spin more than that. 2-3rd goes from about 6100 to 4900 +/-. You can feel the engine lug a bit. But, this is at 11psi. But really, this is pretty much the boost I run all the time, just no place around here for more than that. I'm thinking of just having them loosen it a bit to match my actual use.
Thread Starter
Joined: Nov 2009
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From: THORNTON, PA (NEAR PHILLY)
Thread Starter
Joined: Nov 2009
Posts: 1,621
Likes: 31
From: THORNTON, PA (NEAR PHILLY)
Thread Starter
Joined: Nov 2009
Posts: 1,621
Likes: 31
From: THORNTON, PA (NEAR PHILLY)
Unrelated (or maybe related) - I guess at some point the 83mm turbine may start to become a restriction. Any idea at what point that becomes an issue?
Really not that turdly, 11psi and 3600# weight you cant expect much. That Monza I had was around 3200-3300# race weight I think, it had an LQ4 and the exact same turbo you have...was E85 and blow through though.
13# and stock cam 136mph Island 520whp Denmahs dyno
16# and 216/216 (TU0) cam 145mph Atco 590whp Denmahs dyno
With the stock cam it had a few busted ring lands, smoked like a chimney, but Im starting to think shitty pistons don't affect power that much.
13# and stock cam 136mph Island 520whp Denmahs dyno
16# and 216/216 (TU0) cam 145mph Atco 590whp Denmahs dyno
With the stock cam it had a few busted ring lands, smoked like a chimney, but Im starting to think shitty pistons don't affect power that much.
Last edited by Hank Peabody; Apr 17, 2015 at 07:16 PM.
Launching!
Joined: Feb 2011
Posts: 234
Likes: 1
I take it that your runs were through the mufflers and with a air cleaner.
If so...You are leaving a lot on the table I think.
You have added cid which means more cfm in and out of the motor over the last combo all things being equal.
If you removed the bottle necks I think you would see a increase.
I guess it all depends on what you want.
If you are wanting to optimize it in the configuration you run on the street or are wanting to see what it will do in a "strip only" set up.
If so...You are leaving a lot on the table I think.
You have added cid which means more cfm in and out of the motor over the last combo all things being equal.
If you removed the bottle necks I think you would see a increase.
I guess it all depends on what you want.
If you are wanting to optimize it in the configuration you run on the street or are wanting to see what it will do in a "strip only" set up.
