Low power on a 427
TECH Senior Member
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From: Western Burbs of Detroit
Best of luck. Looks like you found a ton of mistakes and fixed them all. Hope to see you put down 530 rwhp and 500 rwtq brother. Maybe more !! Again best of luck ................
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Teching In
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Yes Ivan dug around and finally found it, what a disaster! When I pulled out the boost gauge they had the ground wire duct taped on to the chassis and I found speaker wiring in there, haha!
Glad you like the STI, really fun car with some snow tires in the winter.
Thanks for you help Larry,
Martin
One thing I've learned from buying used cars, they always need work! No fault at all of the previous owner, just the shop that did the work.
Yes Ivan dug around and finally found it, what a disaster! When I pulled out the boost gauge they had the ground wire duct taped on to the chassis and I found speaker wiring in there, haha!
Glad you like the STI, really fun car with some snow tires in the winter.
Thanks for you help Larry,
Martin
Yes Ivan dug around and finally found it, what a disaster! When I pulled out the boost gauge they had the ground wire duct taped on to the chassis and I found speaker wiring in there, haha!
Glad you like the STI, really fun car with some snow tires in the winter.
Thanks for you help Larry,
Martin
The duct tape is a new one I have to note
glad to help and I'm sure we'll talk again soon
Thread Starter
Teching In
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Well after some more issues finally got everything running right.
500whp and 485 ft-lbs SAE corrected and 515whp and 499 ft-lbs uncorrected. The new cam is smaller than the old cam is quite smoother down low. I'm pretty happy picking up a solid 40-50 ft-lbs of torque and 30whp peak with nicer heads and a smaller cam.
It still has the stock CTS-V plastic intake tube that necks down badly at one point so I'm going to make something nice at the shop and replace it. I took the top of the Volante box off and the air filter off and it picked up only 3-4 whp tops so that's not doing much. It's still a stock LS2 TB so I'll touch that up also and see what the intake along with TB do.
-Martin
500whp and 485 ft-lbs SAE corrected and 515whp and 499 ft-lbs uncorrected. The new cam is smaller than the old cam is quite smoother down low. I'm pretty happy picking up a solid 40-50 ft-lbs of torque and 30whp peak with nicer heads and a smaller cam.
It still has the stock CTS-V plastic intake tube that necks down badly at one point so I'm going to make something nice at the shop and replace it. I took the top of the Volante box off and the air filter off and it picked up only 3-4 whp tops so that's not doing much. It's still a stock LS2 TB so I'll touch that up also and see what the intake along with TB do.
-Martin
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Verdad Gallardo Thread Starter
Teching In
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We converted the car to speed density and made a 4" intake tube with filter to get rid of the stock CTS-V plastic intake tube. I was quite surprised at the final results. Two pulls back to back and it made 539whp and 536whp, quite a gain. Torque was still just under 500ft-lbs. Next is porting the TB. The FAST intake is still unported and if I get really ambitious I'll take that off and see what I can do. Can't drive the damn thing anyways with all the snow on the ground here in Chicago.. bummer.
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Kpa (pressure) logs prior to the intake tube showed 98 Kpa dropping 94 Kpa at redline. With the new intake tube the manifold pressure stays at 98 Kpa the whole time.
Last edited by martin@ams; Jan 13, 2009 at 11:53 AM.
Maybe next time
Congrats on the power
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I finally drove the car on the roads. Cold shitty roads = instant wheel spin. It's suppose to be 34 degrees tomorrow, maybe I'll drive it to the shop. Forgot to mention I love the ACT twin disc in there, light pedal pressure and great engagement.
Probably not, the new cam is smaller than the old cam.
I finally drove the car on the roads. Cold shitty roads = instant wheel spin. It's suppose to be 34 degrees tomorrow, maybe I'll drive it to the shop. Forgot to mention I love the ACT twin disc in there, light pedal pressure and great engagement.
I finally drove the car on the roads. Cold shitty roads = instant wheel spin. It's suppose to be 34 degrees tomorrow, maybe I'll drive it to the shop. Forgot to mention I love the ACT twin disc in there, light pedal pressure and great engagement.
The old heads were small bore 225's. Perfect for my 383, but not a 427. I'm sure they could have had the chambers opened up for the larger bore though. Either way sweet power from a smaller cam 427 set up for a heavy car.
Martin, how do you like the speed density tune and was/is it a pain to get the car driving smooth? I've thougth about it as long as it doesn't require constant tweaking, but it seems like everyone around here wants to keep the maf. I have a larger cam and less engine so I'm sure it will make things a little different.
I see ACT makes ls clutches now, but didn't know they had a twin disk. Does it use a sprung hub and organic disks?
Martin, how do you like the speed density tune and was/is it a pain to get the car driving smooth? I've thougth about it as long as it doesn't require constant tweaking, but it seems like everyone around here wants to keep the maf. I have a larger cam and less engine so I'm sure it will make things a little different.
I see ACT makes ls clutches now, but didn't know they had a twin disk. Does it use a sprung hub and organic disks?
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Joined: Jul 2007
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From: dekalb, IL
Im in dekalb and would love too see that beast. Im gonna go cruise around with that beast I think we are all planning a meet in joliet in spring at naf's track day Let me know if your interested
We converted the car to speed density and made a 4" intake tube with filter to get rid of the stock CTS-V plastic intake tube. I was quite surprised at the final results. Two pulls back to back and it made 539whp and 536whp, quite a gain. Torque was still just under 500ft-lbs. Next is porting the TB. The FAST intake is still unported and if I get really ambitious I'll take that off and see what I can do. Can't drive the damn thing anyways with all the snow on the ground here in Chicago.. bummer.
Thread Starter
Teching In
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The old heads were small bore 225's. Perfect for my 383, but not a 427. I'm sure they could have had the chambers opened up for the larger bore though. Either way sweet power from a smaller cam 427 set up for a heavy car.
Martin, how do you like the speed density tune and was/is it a pain to get the car driving smooth? I've thougth about it as long as it doesn't require constant tweaking, but it seems like everyone around here wants to keep the maf. I have a larger cam and less engine so I'm sure it will make things a little different.
I see ACT makes ls clutches now, but didn't know they had a twin disk. Does it use a sprung hub and organic disks?
Martin, how do you like the speed density tune and was/is it a pain to get the car driving smooth? I've thougth about it as long as it doesn't require constant tweaking, but it seems like everyone around here wants to keep the maf. I have a larger cam and less engine so I'm sure it will make things a little different.
I see ACT makes ls clutches now, but didn't know they had a twin disk. Does it use a sprung hub and organic disks?
I've been driving the car around and the speed density tune is spot on. I'd venture to say that between Chris and I we have about 15 years of tuning experience and we've tuned close to 500 cars on speed density, mostly turbocharged. Sorry not trying to brag, just letting other people on here know that we have a lot of experience with it and honestly tuning NA cars is a piece of cake compared to the turbo cars, not sure why people would be hesitant of the SD conversion.
if the IAT compensation is setup correctly a car on SD will run great year 'round, unless of course you start changing parts. Also the NA motor is a little less sensitive to A/F 's than a turbo motor so you have a larger margin of error. It's cold out here now and I'll keep my eye on the tune and see how it changes once we hit spring.
I love the ACT clutch. It's sprung hub dual disc organic. I put in a OEM LS7 Z06 clutch in there when I first picked up the car and the pedal feel and engagement of the twin disc ACT is very similar. I highly recommend it, especially when this street friendly organic version can hold 850 ft-lbs of torque.
BTW I love the instant torque of the V8, this is my first NA big displacement car and it's going to be hard to go back to my GT35R EVO
When it warm up I'll do a little highway pull between the 'V and the EVO on pump gas, should be interesting.-Martin
Ed,
I've been driving the car around and the speed density tune is spot on. I'd venture to say that between Chris and I we have about 15 years of tuning experience and we've tuned close to 500 cars on speed density, mostly turbocharged. Sorry not trying to brag, just letting other people on here know that we have a lot of experience with it and honestly tuning NA cars is a piece of cake compared to the turbo cars, not sure why people would be hesitant of the SD conversion.
if the IAT compensation is setup correctly a car on SD will run great year 'round, unless of course you start changing parts. Also the NA motor is a little less sensitive to A/F 's than a turbo motor so you have a larger margin of error. It's cold out here now and I'll keep my eye on the tune and see how it changes once we hit spring.
I love the ACT clutch. It's sprung hub dual disc organic. I put in a OEM LS7 Z06 clutch in there when I first picked up the car and the pedal feel and engagement of the twin disc ACT is very similar. I highly recommend it, especially when this street friendly organic version can hold 850 ft-lbs of torque.
BTW I love the instant torque of the V8, this is my first NA big displacement car and it's going to be hard to go back to my GT35R EVO When it warm up I'll do a little highway pull between the 'V and the EVO on pump gas, should be interesting.
-Martin
I've been driving the car around and the speed density tune is spot on. I'd venture to say that between Chris and I we have about 15 years of tuning experience and we've tuned close to 500 cars on speed density, mostly turbocharged. Sorry not trying to brag, just letting other people on here know that we have a lot of experience with it and honestly tuning NA cars is a piece of cake compared to the turbo cars, not sure why people would be hesitant of the SD conversion.
if the IAT compensation is setup correctly a car on SD will run great year 'round, unless of course you start changing parts. Also the NA motor is a little less sensitive to A/F 's than a turbo motor so you have a larger margin of error. It's cold out here now and I'll keep my eye on the tune and see how it changes once we hit spring.
I love the ACT clutch. It's sprung hub dual disc organic. I put in a OEM LS7 Z06 clutch in there when I first picked up the car and the pedal feel and engagement of the twin disc ACT is very similar. I highly recommend it, especially when this street friendly organic version can hold 850 ft-lbs of torque.
BTW I love the instant torque of the V8, this is my first NA big displacement car and it's going to be hard to go back to my GT35R EVO
When it warm up I'll do a little highway pull between the 'V and the EVO on pump gas, should be interesting.-Martin
That new clutch sounds nice, is it spendy? It's nice that the domestic clutches hold so much torque since they're usually larger in size. I might try out a SD tune and see what my 383 will do. I'm sure it would be a bit more of a pain to tune due to the intake pressure fluctuation from the larger cam/smaller engine. I've added a lg big 3(dual 3") exhaust since my last dyno.