LS3 engine, new cam no real HP gain?
#1
Pro
Thread Starter
LS3 engine, new cam no real HP gain?
Car is 2011 MT GS with dry sump.
Dynoed stock at 500 miles, 340 rwhp on a Mustang dyno.
Added Spinmonster cam (230/234 114+2), ported intake, ported TB, TR6's and Lunati valve spring package at 4,000 miles.
Tuned on same dyno car made 368 rwhp peak, but only saw a gain from 5250 rpm and up (peak gain 28 hp). Torque followed the stock graph line as well.
I ran the car at the track and it recorded the same mph (114mph) as stock, ET improved a few tenths (12.35) but it was due to better short time / track prep.
I hadn't seen the dyno chart til yesterday so I figured the car had gained power across the board but was being held back by the exhaust so I added 1 7/8" OBX headers, 3" x-pipe and stock ZO6 mufflers.
Dynoed on the same dyno there was an across the board gain of 23 rwhp ending with 392 rwhp and 371 torque.
Looking at the dyno run tables the MAF is showing enough air moving into the engine to support 580 crank horsepower which would be close to 500 rwhp which is where I thought I would be.
I realize I am mostly spouting numbers here, but the car doesn't run the way it should either. I am going to pull a few rockers off and check the lift of the cam vs the cam card, I wasn't there for the install but I trust the installer.
Sign me baffled in Boca????
Dynoed stock at 500 miles, 340 rwhp on a Mustang dyno.
Added Spinmonster cam (230/234 114+2), ported intake, ported TB, TR6's and Lunati valve spring package at 4,000 miles.
Tuned on same dyno car made 368 rwhp peak, but only saw a gain from 5250 rpm and up (peak gain 28 hp). Torque followed the stock graph line as well.
I ran the car at the track and it recorded the same mph (114mph) as stock, ET improved a few tenths (12.35) but it was due to better short time / track prep.
I hadn't seen the dyno chart til yesterday so I figured the car had gained power across the board but was being held back by the exhaust so I added 1 7/8" OBX headers, 3" x-pipe and stock ZO6 mufflers.
Dynoed on the same dyno there was an across the board gain of 23 rwhp ending with 392 rwhp and 371 torque.
Looking at the dyno run tables the MAF is showing enough air moving into the engine to support 580 crank horsepower which would be close to 500 rwhp which is where I thought I would be.
I realize I am mostly spouting numbers here, but the car doesn't run the way it should either. I am going to pull a few rockers off and check the lift of the cam vs the cam card, I wasn't there for the install but I trust the installer.
Sign me baffled in Boca????
Last edited by Kerrdogg; 04-25-2012 at 05:11 PM.
#2
Melting Slicks
Boy that does seem to be way off normal gains. Are you thinking mis-boxed cam?
When I was young I worked at a warehouse and the wrong stuff would get shipped very frequently. I'd double check everything ordered for an engine/performance application.
When I was young I worked at a warehouse and the wrong stuff would get shipped very frequently. I'd double check everything ordered for an engine/performance application.
Last edited by ctusser; 04-25-2012 at 05:27 PM.
#3
Drifting
Iv'e got the same cam in my o8 with an A6 and a 3600 converter and puting down over 440 rwhp. Somethings wrong with either your cam or your tune. I'm running Zo6 axle backs and 1 3/4 headers. Turned 10.71@127mph with this combo on a hot muggy Florida evening.(1600 DA). Better talk to your tuner.....
#4
Le Mans Master
The cam could even be put in a tooth off, which depending on which gear could be 4 or 8 degrees. If it was retarded, I have seen them loose 20-30 hp and still run ok. Just food for thought.
Also I am sure you already know, the Mustang dyno reads lower than dyno jet if you are comparing yours to other peoples.
Also I am sure you already know, the Mustang dyno reads lower than dyno jet if you are comparing yours to other peoples.
#5
Drifting
The cam could even be put in a tooth off, which depending on which gear could be 4 or 8 degrees. If it was retarded, I have seen them loose 20-30 hp and still run ok. Just food for thought.
Also I am sure you already know, the Mustang dyno reads lower than dyno jet if you are comparing yours to other peoples.
Also I am sure you already know, the Mustang dyno reads lower than dyno jet if you are comparing yours to other peoples.
#6
Safety Car
Very odd. Tune and/or cam issue. Your track times won't be any better unless you get some sticky tires.
#7
Iv'e got the same cam in my o8 with an A6 and a 3600 converter and puting down over 440 rwhp. Somethings wrong with either your cam or your tune. I'm running Zo6 axle backs and 1 3/4 headers. Turned 10.71@127mph with this combo on a hot muggy Florida evening.(1600 DA). Better talk to your tuner.....
#8
Le Mans Master
Iv'e got the same cam in my o8 with an A6 and a 3600 converter and puting down over 440 rwhp. Somethings wrong with either your cam or your tune. I'm running Zo6 axle backs and 1 3/4 headers. Turned 10.71@127mph with this combo on a hot muggy Florida evening.(1600 DA). Better talk to your tuner.....
#9
Race Director
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Something's definitely wrong. Whoever put it in needs to be taking it out. Was it a forum vendor?
Interested to see what happens.
How does the car sound with the cam? Who knows, maybe it was ground with the wrong duration or something.
Interested to see what happens.
How does the car sound with the cam? Who knows, maybe it was ground with the wrong duration or something.
#10
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Theofel...This is off the topic but I noticed you said you have an 08 A6. I do too. Im about to put on Kooks headers on my A6. Currently all I have is Borla exhaust & Vararam ram air unit. My question to you is have you had any modifications done to your auto tranny to accomodate the extra power at 440rwhp? What is a 3600 converter if you mind me asking? Im just trying to make sure the stock tranny can handle the headers and tune. Any advice would be apprciated. Im new to the corvette scene so alot of this stuff is Russian to me lol. Sorry for being off topic. Thanks.
Just google "aftermarket torque converter" to learn more about it.
#11
Racer
How does the car feel? I mean mine was night and day difference from the stock cam to the Pat G cam. The car is an animal after the cam swap and I don't have a ported intake manifold or throttle body on mine. Something doesnt seem right. I mean even with traction issues 114 mph is way low, stock ls3 cars go faster than that.
#12
Tech Contributor
Kerrdogg I will be happy to scan you next time we're at the track so we can see what's going on....hmmm....doesn't John work with you? He has HP Tuners, get a scan of a run and send it to me and I'll give you my thoughts.
#13
Drifting
Theofel...This is off the topic but I noticed you said you have an 08 A6. I do too. Im about to put on Kooks headers on my A6. Currently all I have is Borla exhaust & Vararam ram air unit. My question to you is have you had any modifications done to your auto tranny to accomodate the extra power at 440rwhp? What is a 3600 converter if you mind me asking? Im just trying to make sure the stock tranny can handle the headers and tune. Any advice would be apprciated. Im new to the corvette scene so alot of this stuff is Russian to me lol. Sorry for being off topic. Thanks.
Last edited by theofel; 04-26-2012 at 09:46 AM.
#14
Le Mans Master
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St. Jude Donor '11-'12-'13-'14
Just like I said in our emails John, it's either the install, improper grind, or the tune. Good luck and keep us posted.
#15
Le Mans Master
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Something is certainly off here. With that cam in any LS3 car I will consistently see 465 to 480 to the wheels with headers and a CAI. This doesn't matter if its a F or a Y body LS3 car.
#16
Pro
Thread Starter
Traction is not a problem with this setup I too expected an animal, it's is one but I would call it a sheep, not the wolf I was looking for.
For those of you with this same cam how loud is your valve train? Mine seems a bit loud, like a sewing machine but loud none the less.
The cam was installed by a friend, he is a GM mechanic and has a nice twin turbo C5.
One install problem was that the cam was ground to a one bolt blank and GS's come with 3 bolt blanks, he had a one bolt timing gear and used it for the install... I would think if the cam was one tooth off it would have PTV issues???
For those of you with this same cam how loud is your valve train? Mine seems a bit loud, like a sewing machine but loud none the less.
The cam was installed by a friend, he is a GM mechanic and has a nice twin turbo C5.
One install problem was that the cam was ground to a one bolt blank and GS's come with 3 bolt blanks, he had a one bolt timing gear and used it for the install... I would think if the cam was one tooth off it would have PTV issues???
#17
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St. Jude Donor '11-'12-'13-'14
I've had friends with the "Spin" cam with the lobes reversed. I swear I hear more about that cam having grind issues but that's perhaps because it's a popular choice. That's why I insisted on having a cam doctor printout with my cam.
It sucks but you might need to take it back out and have it checked if there's not a way to check it when it's installed.
It sucks but you might need to take it back out and have it checked if there's not a way to check it when it's installed.
#18
Pro
Thread Starter
I mean I have done weekend builds before (usually HCI), NOS and turbo installs where you gain a 100 or 200 hp, the difference is night and day, in this case the big difference hasn't happened yet.
My fear is if I keep driving it I will hurt something so it is parked til I can wrench on it.
My goal was a 125mph car in the 1/4, will pull it apart tomorrow eve or Sat am I guess.
#20
Pro
Thread Starter
I am going to check the lift of the cam by dial indicator and see if it matches the cam card, if it was ground reversed or wrong it could show up there. I called my buddy who sold his co to Comp a few years ago and worked there for a while, he said it could be as easy as someone putting the master in the wrong storage slot or loading it in the wrong side of the grinder....