Added MTI Stealth cam, LT's + results of...
05-19-2005, 04:06 PM
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Added MTI Stealth cam, LT's + results of...
My '99 FRC managed 324hp/330 torque on a Dynojet last year. Only mods were BW and MAF-T.
I had Phoenix Performance (Phila. area) install an MTI Stealth II cam (224/220/581/116), LS6 manifold and Kooks 1.75 LT's plumbed back to the stock cats and exhaust using all the O2 sensors, etc. (My goal was to preserve as much stock as possible to minimize the possbility of codes, etc.) I also did not want any huge cam since this is a daily driver and I do not race. Since the mods, have driven about 900 miles so I know the PCM has adjusted about as much as it ever will. (It took about 200 miles for the part throttle performance to stabilize.)
I just had the same dyno and operator test the results of the mods today and I am confused a bit.
HP went from 324 to 360, Torque went from 330 to 339. This really surprised me since I expected more torque. The PCM is still untuned but the operator did not expect any huge increase since my trims, KR (none), and O2's seem about optimal. We used a wide band for the fueling on the dyno and the final ratio giving the best HP was in the 12.8 to 12.4 area. It was close to 13.0 at 3000 rpm but drifted into the high twelves from 3500 or so and finally ended at 12.3 or 4 at 6000 rpm. (I will try to post the graphs soon...)
Stock limiter stop the revs at 6200 and the idle is clean and a little lopey at 730rpm. Low RPM torque feels great everywhere and there is a noticeable surge around 4500 or so up to the 6200 limiter. The car before mine was a late model Z06 equipped for SCCA racing with a cage, tires, etc. and a tweaked PCM but no other mods except for the mufflers. It delivered 361 on the rollers but I did not get the torque.
Am very pleased with the drivability and responsiveness but am surprised the torque is not in the 350 or 360 range. Is this due to the stock valves and ports? Is there anything to be gained going for a formal tune? (I used Autotap to scan everything after the install and used the MAF-T to adjust set the LTrims, etc.)
Opinions, Comments?
I had Phoenix Performance (Phila. area) install an MTI Stealth II cam (224/220/581/116), LS6 manifold and Kooks 1.75 LT's plumbed back to the stock cats and exhaust using all the O2 sensors, etc. (My goal was to preserve as much stock as possible to minimize the possbility of codes, etc.) I also did not want any huge cam since this is a daily driver and I do not race. Since the mods, have driven about 900 miles so I know the PCM has adjusted about as much as it ever will. (It took about 200 miles for the part throttle performance to stabilize.)
I just had the same dyno and operator test the results of the mods today and I am confused a bit.
HP went from 324 to 360, Torque went from 330 to 339. This really surprised me since I expected more torque. The PCM is still untuned but the operator did not expect any huge increase since my trims, KR (none), and O2's seem about optimal. We used a wide band for the fueling on the dyno and the final ratio giving the best HP was in the 12.8 to 12.4 area. It was close to 13.0 at 3000 rpm but drifted into the high twelves from 3500 or so and finally ended at 12.3 or 4 at 6000 rpm. (I will try to post the graphs soon...)
Stock limiter stop the revs at 6200 and the idle is clean and a little lopey at 730rpm. Low RPM torque feels great everywhere and there is a noticeable surge around 4500 or so up to the 6200 limiter. The car before mine was a late model Z06 equipped for SCCA racing with a cage, tires, etc. and a tweaked PCM but no other mods except for the mufflers. It delivered 361 on the rollers but I did not get the torque.
Am very pleased with the drivability and responsiveness but am surprised the torque is not in the 350 or 360 range. Is this due to the stock valves and ports? Is there anything to be gained going for a formal tune? (I used Autotap to scan everything after the install and used the MAF-T to adjust set the LTrims, etc.)
Opinions, Comments?
05-20-2005, 09:48 AM
#7
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Originally Posted by loudsam
If I were you, I'd get it tuned. 
Also, adjust your idle to 900rpm for smoothness and you wont hear any lope.Not bad for a mild cam-only...wait till you do heads and Intake!
05-20-2005, 10:49 AM
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Originally Posted by Jack Behrle
My '99 FRC managed 324hp/330 torque on a Dynojet last year. Only mods were BW and MAF-T.
I had Phoenix Performance (Phila. area) install an MTI Stealth II cam (224/220/581/116), LS6 manifold and Kooks 1.75 LT's plumbed back to the stock cats and exhaust using all the O2 sensors, etc. (My goal was to preserve as much stock as possible to minimize the possbility of codes, etc.) I also did not want any huge cam since this is a daily driver and I do not race. Since the mods, have driven about 900 miles so I know the PCM has adjusted about as much as it ever will. (It took about 200 miles for the part throttle performance to stabilize.)
I just had the same dyno and operator test the results of the mods today and I am confused a bit.
HP went from 324 to 360, Torque went from 330 to 339. This really surprised me since I expected more torque. The PCM is still untuned but the operator did not expect any huge increase since my trims, KR (none), and O2's seem about optimal. We used a wide band for the fueling on the dyno and the final ratio giving the best HP was in the 12.8 to 12.4 area. It was close to 13.0 at 3000 rpm but drifted into the high twelves from 3500 or so and finally ended at 12.3 or 4 at 6000 rpm. (I will try to post the graphs soon...)
Stock limiter stop the revs at 6200 and the idle is clean and a little lopey at 730rpm. Low RPM torque feels great everywhere and there is a noticeable surge around 4500 or so up to the 6200 limiter. The car before mine was a late model Z06 equipped for SCCA racing with a cage, tires, etc. and a tweaked PCM but no other mods except for the mufflers. It delivered 361 on the rollers but I did not get the torque.
Am very pleased with the drivability and responsiveness but am surprised the torque is not in the 350 or 360 range. Is this due to the stock valves and ports? Is there anything to be gained going for a formal tune? (I used Autotap to scan everything after the install and used the MAF-T to adjust set the LTrims, etc.)
Opinions, Comments?
I had Phoenix Performance (Phila. area) install an MTI Stealth II cam (224/220/581/116), LS6 manifold and Kooks 1.75 LT's plumbed back to the stock cats and exhaust using all the O2 sensors, etc. (My goal was to preserve as much stock as possible to minimize the possbility of codes, etc.) I also did not want any huge cam since this is a daily driver and I do not race. Since the mods, have driven about 900 miles so I know the PCM has adjusted about as much as it ever will. (It took about 200 miles for the part throttle performance to stabilize.)
I just had the same dyno and operator test the results of the mods today and I am confused a bit.
HP went from 324 to 360, Torque went from 330 to 339. This really surprised me since I expected more torque. The PCM is still untuned but the operator did not expect any huge increase since my trims, KR (none), and O2's seem about optimal. We used a wide band for the fueling on the dyno and the final ratio giving the best HP was in the 12.8 to 12.4 area. It was close to 13.0 at 3000 rpm but drifted into the high twelves from 3500 or so and finally ended at 12.3 or 4 at 6000 rpm. (I will try to post the graphs soon...)
Stock limiter stop the revs at 6200 and the idle is clean and a little lopey at 730rpm. Low RPM torque feels great everywhere and there is a noticeable surge around 4500 or so up to the 6200 limiter. The car before mine was a late model Z06 equipped for SCCA racing with a cage, tires, etc. and a tweaked PCM but no other mods except for the mufflers. It delivered 361 on the rollers but I did not get the torque.
Am very pleased with the drivability and responsiveness but am surprised the torque is not in the 350 or 360 range. Is this due to the stock valves and ports? Is there anything to be gained going for a formal tune? (I used Autotap to scan everything after the install and used the MAF-T to adjust set the LTrims, etc.)
Opinions, Comments?
You'll pick up quite a bit more RWHP and especially torque. (I would guess close to 400RWHP and 370RWTQ
05-20-2005, 11:57 AM
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Thanks for all your replies. I will have to consider a formal tune and perhaps hi flow Cats. From all that I have read, the consensus seems to be that Hi Flows won't add much more than 5 hp. Does not seem worth it.
Jack
Jack
05-20-2005, 02:15 PM
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I agree that a tune will make lots of difference. See signature below for Stealth II results after tuning and with high flow cats, pulleys etc. With this set up dyno results with trans locked were 399.4 hp and 375.2 TQ.
Good luck with your tune.
Good luck with your tune.
Last edited by MadDawg; 05-20-2005 at 02:18 PM.
05-21-2005, 08:33 AM
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Need tuner recommendation..Phila Area
OK, I'm convinced, its off the see the tuner...but who?
After recent dyno, my cam and LT machine probably could use some editing. Any recommendations?
Jack
After recent dyno, my cam and LT machine probably could use some editing. Any recommendations?
Jack
