Power Lose after SR install?
Thread Starter
Burning Brakes
Joined: Mar 2005
Posts: 1,164
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From: Middle Earth
Power Lose after SR install?
am I imagining things or did I lose a lot of power by just installing a ported SR? I thought I would lose some but it feels like I lost a good bit. Do I need to go ahead and do a cam swap? 
Race Director
Joined: May 2001
Posts: 14,165
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On an otherwise stock engine?
You probably lost most of the low end power gained by the "tuned port" technology that you had. If there was any power to be had on the upper end your cam either can't take advantage of the extra airflow or the tune is so far off now that it's not even close to running right.
It's all about picking the right combination of parts.
You probably lost most of the low end power gained by the "tuned port" technology that you had. If there was any power to be had on the upper end your cam either can't take advantage of the extra airflow or the tune is so far off now that it's not even close to running right.
It's all about picking the right combination of parts.
Race Director
Joined: Aug 2000
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Cruise-In II Veteran
On a DD stock engine,the factory TPI will provide the most SOTP power off the line and passing.I even tried larger tube runners and SLP's tubes and found it felt sluggish off the line and low speed driving.I put the factory TPI back on and it felt great off the line and had better throttle response.Thats due to the engine being stock internally.
Sounds like you should have a cam and headers to complete the SR set up but even with that cam,the car wont feel as fast off the line but once you start to hit 2,000 rpms or so its gonna start pulling harder,making decent torque and power across the rpm band.
Does your car now pull any harder in the mid 2000 range and up?If so thats the SR beginning to work.
You may even need a tune/chip to make things run better with the cam change and etc.
Just remember,on a stock engine,intake mods/larger TB's, and parts wont make the car feel any faster.You would need real track times to see if there was any benefits.
Sounds like you should have a cam and headers to complete the SR set up but even with that cam,the car wont feel as fast off the line but once you start to hit 2,000 rpms or so its gonna start pulling harder,making decent torque and power across the rpm band.
Does your car now pull any harder in the mid 2000 range and up?If so thats the SR beginning to work.
You may even need a tune/chip to make things run better with the cam change and etc.
Just remember,on a stock engine,intake mods/larger TB's, and parts wont make the car feel any faster.You would need real track times to see if there was any benefits.
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Race Director
Joined: Aug 2000
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Cruise-In II Veteran
One more thing,whats the rear gear ratio of your car?If its less than 3.07 -3.42 than those kind of mods may benefit with a gear change.If you have the automatic transmission,the torque converter can be changed to increase the offline performance as well to a higher stall speed over stock.
Last edited by Aggravated4life; Sep 6, 2005 at 10:07 PM.
Team Owner
Joined: Sep 2002
Posts: 22,209
Likes: 12
From: OBAMA IS HITLER
Bill's86 is right. I have the full SR intake, as well as an Accel #74219 cam and aftermarket fully CNC'd heads. I can tell you this package WAKES the hell out of the stock L98 in a major way, and you will FLY as soon as you hit mid 2000-rpms -- straight on thru to the upper 5,000 rpms. This is a helluva blast.....alot of money but daily grins from ear to ear, ball-bearing' guaranteed.
I wanted something real and this is definitely it. No need to wonder if there's SOTP improvment by comparing numbers, shmumbers. You wont need a track or dyno to make calculations. This is a no-nonsense package that WORKS, throws you back and has wonderful power, and major improvment over stock TPI across the band, in every way. By the way, I feel more power - not less - from a dead stop vs. factory setup.
I wanted something real and this is definitely it. No need to wonder if there's SOTP improvment by comparing numbers, shmumbers. You wont need a track or dyno to make calculations. This is a no-nonsense package that WORKS, throws you back and has wonderful power, and major improvment over stock TPI across the band, in every way. By the way, I feel more power - not less - from a dead stop vs. factory setup.
Last edited by Red Tornado; Sep 6, 2005 at 10:15 PM.
Race Director
Joined: Feb 2004
Posts: 12,518
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Originally Posted by Hot Rod 90
Bill's86 is right. I have the full SR intake, as well as an Accel #74219 cam and aftermarket fully CNC'd heads. I can tell you this package WAKES the hell out of the stock L98 in a major way, and you will FLY as soon as you hit mid 2000-rpms -- straight on thru to the upper 5,000 rpms. This is a helluva blast.....alot of money but daily grins from ear to ear, ball-bearing' guaranteed.
I wanted something real and this is definitely it. No need to wonder if there's SOTP improvment by comparing numbers, shmumbers. You wont need a track or dyno to make calculations. This is a no-nonsense package that WORKS, throws you back and has wonderful power, and major improvment over stock TPI across the band, in every way. By the way, I feel more power - not less - from a dead stop vs. factory setup.
I wanted something real and this is definitely it. No need to wonder if there's SOTP improvment by comparing numbers, shmumbers. You wont need a track or dyno to make calculations. This is a no-nonsense package that WORKS, throws you back and has wonderful power, and major improvment over stock TPI across the band, in every way. By the way, I feel more power - not less - from a dead stop vs. factory setup.
What he said.
Team Owner
Joined: Sep 2002
Posts: 22,209
Likes: 12
From: OBAMA IS HITLER
vader is right.
LPE/Accel #74219 cam:
http://www.lingenfelter.com/Merchant...Category_Code=
You might find this little tidbit useful, on the subject of your question:
http://home.adelphia.net/~lebeter/ac...ap/page2-2.htm
LPE/Accel #74219 cam:
http://www.lingenfelter.com/Merchant...Category_Code=
You might find this little tidbit useful, on the subject of your question:
http://home.adelphia.net/~lebeter/ac...ap/page2-2.htm
Team Owner
Joined: Sep 2002
Posts: 22,209
Likes: 12
From: OBAMA IS HITLER
Originally Posted by jack the stripper
hey hot-rod, what kind of aftermarket heads did you use?
click on "engine R&D"
click on "engine components"
click on "air flow research heads"
p/n 500-525
actual measurments of chambers turned out to be 56cc, not 54cc. 100% CNC'd intake/exhaust, these heads match AFR's old 190cc version (no longer sold), but are 187cc, the flow is right with AFR's own competition ported heads, I got 7/16" studs. I paid $100 less, price included shipping.
not cheap by any means, but I wasn't interested in ever buying another set of heads again.
these were looked over & tested by the machine shop, airtight, no quality problems, were untouched and installed right out of the box.
the machine shop was astounded as to why a customer would buy such "monster heads for a street application", i told them the answer is obvious, i don't like import punks ruining our streets
they tacitly agreed 
Last edited by Red Tornado; Sep 7, 2005 at 11:37 AM.
