Step inside to gain knowledge!!!! Detailed A/B comparisons with results!!!
Step inside to gain knowledge!!!! Detailed A/B comparisons with results!!! Its been quite an interesting week at Vengeance Racing. Allngn_c5 made the trip down from Michigan to make some changes to his current combination. Allngn_C5 has a 2000 FRC Vette with a 402 LS2 and supporting bolt ons.
The goal of this build is to increase drivability while increasing overall horsepower without sacrificing bottom end torque.
Changes to be made are:
Baseline vehicle upon arrival
Installation of Racetronix fuel system
Removal of LGM 1 3/4 Longtubes
Installation of American Racing 1 7/8 Longtubes
Dyno vehicle to verify changes
Remove AFR 205 cylinder heads
Install Trickflow 215cc cylinder heads
Dyno vehicle to verify changes
Remove LG G6X3 camshaft
Install Vengeance spec custom camshaft
Dyno vehicle to verify changes
When I arrived at the shop Monday morning Doug was already in the parking lot waiting for us. We got the shop rolling and took Dougs vette to the dyno for a baseline prior to starting the modifications. Initial numbers were 494.85/484.17...
After getting baseline #s it was time to hit the rack and swap some parts. Doug wanted to add a Racetronix fuel system to his car to ensure he wasnt going have any fuel pressure issues in the future. We did verify fuel pressure on the dyno during the baseline and fuel pressure maintained 58psi with zero knock retard showing on the log file.
After the Racetronix was installed we removed the LGM 1 3/4 longtubes and replaced them with American Racing 1 7/8 longtubes. Both systems are using NON catted X pipes and bolting directly to the LGM Big 3 exhaust (VERY nice piece btw!!!)
Now its time to go back to the dyno to see what changes the header swap made. Initial pull was 511.37/491.30... This is an overall gain of 16.52RWHP and 7.13RWTQ.. The graph below tells more of the story though. The American Racing headers actually produce more torque in the lower RPMs, but they show a decrease in torque Vs the LGs at around 3750 to 4500rpm. After 4500rpm the American Racing longtubes pull from the LG 1 3/4s by an average of 10/10.
Now that the header swap has been verified it is time to remove the AFR 205cc Cylinder heads and install TrickFlow 215cc Cylinder Heads. The AFR heads had a combustion chamber of 58.5. The Trickflow heads were milled to 59cc. The Trickflow heads were also opened up to a 4" bore to match the shortblock. Yella Terra rockers were installed to replace the OE rockers and 7.500 pushrods were installed to replace the 7.400s used with the AFR combination. No other changes were made at this time. Results were 539.39/507.39. This is a gain of 28.02RWHP/16.09RWTQ
The results speak for themselves. While the TFS heads were optimized for the 4" bore the power gained is quite impressive comparing two extremely high quality cylinder heads. You can see where the large displacement engine wanted the additional airflow of the 215cc head.
Now its time for the cam swap. The G6X3 had been performing extremely well up to this point, but Doug wanted to see if he could get better street manners and possibly improve power even more. So we removed the G6X3 and installed a custom cam. We opted for slightly more duration/less lift/wider LSA... The camshaft selected was 239/243 .623 /.623 113+3... Compared to the LG camshaft we added 4* of duration to the intake/1* to the exhaust.. Took almost .30 lift off of the intake and widened the LSA by 2*... Results are quite interesting for so many different changes going on with the camshaft. Results are 541.14/505.36... That is a PEAK gain of 1.75RWHP peak and a PEAK LOSS of 2.03RWTQ. Notice the powerbands are very similar thru most of the curve with the Vengeance cam actually picking up 10rwtq under the curve at points.
Overall drivability has been improved and there is a noticable difference in valvetrain noise as well. The TFS/Yella Terra/Vengeance spec cam seems to be much quieter under the hood Vs the AFRs with shimmed springs/G6X3 camshaft/stock rockers.
Here is the graph showing the baseline #s as the car came in with the final #s as the car left.
Actual gains are 46.29RWHP and 21.19RWTQ
After all of the changes were made and all of the testing was done we added the following items before the car goes back to Michigan
Catch Can
Metco Breather
Flow Matched/Balanced customers 42lb/hr fuel injectors
DMH dual electric cutouts. Doug saw these on another customers car and thought they were really cool. Unfortunately they did not pick up a SINGLE RWHP over the LGM Big 3 exhaust. The LGM exhaust lived up to its name and performed beyond our expectations.
Testing is over and Mike is out finalizing the tune. I would like to say that Doug was present for EVERY dyno pull/modification. We allowed Doug to be a part of all of the work as to give him first hand experience and give him the confidence to know exactly how his car is performing and where his money is being spent. It actually worked out to our benefit because Doug saw our grill outside that we use on dyno days and he has cooked us lunch everyday since he has been here
Thanx again Doug for making the drive to Vengeance. We appreciate all of the good cooking and it was cool hanging out with you as well!!!
The goal of this build is to increase drivability while increasing overall horsepower without sacrificing bottom end torque.
Changes to be made are:
Baseline vehicle upon arrival
Installation of Racetronix fuel system
Removal of LGM 1 3/4 Longtubes
Installation of American Racing 1 7/8 Longtubes
Dyno vehicle to verify changes
Remove AFR 205 cylinder heads
Install Trickflow 215cc cylinder heads
Dyno vehicle to verify changes
Remove LG G6X3 camshaft
Install Vengeance spec custom camshaft
Dyno vehicle to verify changes
When I arrived at the shop Monday morning Doug was already in the parking lot waiting for us. We got the shop rolling and took Dougs vette to the dyno for a baseline prior to starting the modifications. Initial numbers were 494.85/484.17...
After getting baseline #s it was time to hit the rack and swap some parts. Doug wanted to add a Racetronix fuel system to his car to ensure he wasnt going have any fuel pressure issues in the future. We did verify fuel pressure on the dyno during the baseline and fuel pressure maintained 58psi with zero knock retard showing on the log file.
After the Racetronix was installed we removed the LGM 1 3/4 longtubes and replaced them with American Racing 1 7/8 longtubes. Both systems are using NON catted X pipes and bolting directly to the LGM Big 3 exhaust (VERY nice piece btw!!!)
Now its time to go back to the dyno to see what changes the header swap made. Initial pull was 511.37/491.30... This is an overall gain of 16.52RWHP and 7.13RWTQ.. The graph below tells more of the story though. The American Racing headers actually produce more torque in the lower RPMs, but they show a decrease in torque Vs the LGs at around 3750 to 4500rpm. After 4500rpm the American Racing longtubes pull from the LG 1 3/4s by an average of 10/10.
Now that the header swap has been verified it is time to remove the AFR 205cc Cylinder heads and install TrickFlow 215cc Cylinder Heads. The AFR heads had a combustion chamber of 58.5. The Trickflow heads were milled to 59cc. The Trickflow heads were also opened up to a 4" bore to match the shortblock. Yella Terra rockers were installed to replace the OE rockers and 7.500 pushrods were installed to replace the 7.400s used with the AFR combination. No other changes were made at this time. Results were 539.39/507.39. This is a gain of 28.02RWHP/16.09RWTQ
The results speak for themselves. While the TFS heads were optimized for the 4" bore the power gained is quite impressive comparing two extremely high quality cylinder heads. You can see where the large displacement engine wanted the additional airflow of the 215cc head.
Now its time for the cam swap. The G6X3 had been performing extremely well up to this point, but Doug wanted to see if he could get better street manners and possibly improve power even more. So we removed the G6X3 and installed a custom cam. We opted for slightly more duration/less lift/wider LSA... The camshaft selected was 239/243 .623 /.623 113+3... Compared to the LG camshaft we added 4* of duration to the intake/1* to the exhaust.. Took almost .30 lift off of the intake and widened the LSA by 2*... Results are quite interesting for so many different changes going on with the camshaft. Results are 541.14/505.36... That is a PEAK gain of 1.75RWHP peak and a PEAK LOSS of 2.03RWTQ. Notice the powerbands are very similar thru most of the curve with the Vengeance cam actually picking up 10rwtq under the curve at points.
Overall drivability has been improved and there is a noticable difference in valvetrain noise as well. The TFS/Yella Terra/Vengeance spec cam seems to be much quieter under the hood Vs the AFRs with shimmed springs/G6X3 camshaft/stock rockers.
Here is the graph showing the baseline #s as the car came in with the final #s as the car left.
Actual gains are 46.29RWHP and 21.19RWTQ
After all of the changes were made and all of the testing was done we added the following items before the car goes back to Michigan
Catch Can
Metco Breather
Flow Matched/Balanced customers 42lb/hr fuel injectors
DMH dual electric cutouts. Doug saw these on another customers car and thought they were really cool. Unfortunately they did not pick up a SINGLE RWHP over the LGM Big 3 exhaust. The LGM exhaust lived up to its name and performed beyond our expectations.
Testing is over and Mike is out finalizing the tune. I would like to say that Doug was present for EVERY dyno pull/modification. We allowed Doug to be a part of all of the work as to give him first hand experience and give him the confidence to know exactly how his car is performing and where his money is being spent. It actually worked out to our benefit because Doug saw our grill outside that we use on dyno days and he has cooked us lunch everyday since he has been here
Thanx again Doug for making the drive to Vengeance. We appreciate all of the good cooking and it was cool hanging out with you as well!!!
Great to see such testign at every mod... now you know what gain was caused by what mod.
Very interesting...
I do agree though, a Trick Flow 225 or 235 might have been even better
Very interesting...
I do agree though, a Trick Flow 225 or 235 might have been even better
We wanted the A/B comparison to be as fair as possible. Had we used a TFS 235 the test would have been useless as everyone would have said you cant compare a 205 AFR to a 235 TFS head... We have plenty of experience with a 215 on a 402 and we knew it would do exactly what it did.
awesome work guys.
its so nice to see apples-apples comparison. it was the reason i went through the hassle with my FAST 6 months ago.
curious....what's the reason for the "flat spot" in the torque curve? what is it that causes that?
i can't imagine its a tuning issue...you guys would fix it if it was.
is it some inherent glitch in the "machine"? something hit a natural harmonic and robs power?
its so nice to see apples-apples comparison. it was the reason i went through the hassle with my FAST 6 months ago.
curious....what's the reason for the "flat spot" in the torque curve? what is it that causes that?
i can't imagine its a tuning issue...you guys would fix it if it was.
is it some inherent glitch in the "machine"? something hit a natural harmonic and robs power?
