Big under performance on dyno
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Big under performance on dyno Finally got the car on a dyno yesterday and i felt like i was around 70hp/tq short. Was hugely disapointed. We did a balance test and it didnt show a down cylinder. How should i go about evaluating for this because i think something is very wrong. Motor is a 434 ls7 with stage 2 heads by westcoast cylinder heads cam is 228/240 650/652 114 portedfast 102 by mamo with nw 102 tb and 2" primary header into 3" true duals and 11:8:1 compression. Got 510hp/505tq
Last edited by maroonls1z; Mar 9, 2016 at 07:13 AM.
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From: Coast of San Mateo County Between Pacifica & HMB
Auto? Or Stick? Drivetrain?
Can you post graph? Where are the peaks?
Who specced the Cam? Looks a little small for
434", I would have gone at least 235*/247* depending
On your goals even up to 243*/258*.
just my .02
Good Luck
Can you post graph? Where are the peaks?
Who specced the Cam? Looks a little small for
434", I would have gone at least 235*/247* depending
On your goals even up to 243*/258*.
just my .02
Good Luck
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Joined: Dec 2011
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From: SoCal
That's a pretty big number for such a mild cam on a 434 but there may still be some room for improvement in the tune. Wait to see what Pat says and post the chart. Interested to see how it shakes out. Once it is dialed in properly I am betting it will be a lot of fun on the street.
If you wanted a 550whp daily driver without lope, you probably should have built something with a blower. I've seen bone stock LS9's make 510whp on a Mustang dyno.
No it should be fine. Mine didn't pick up hardly anything by pulling the air filter. Are you speed density? And when you say 3" duals, what exactly are they? What mufflers? Where do they dump? And what brand of headers? What does your valve train consist of? What tires did you have on? Did you say what dyno? Have you took it to the track yet?
Yup!!!
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Joined: Jul 2007
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From: Wilmington, De
I think you should be happy with the results. You can't say that you want a small cam to maintain stock driving characteristics and then expect huge numbers from a naturally aspirated engine. The fact that your horsepower peak is at 5800 RPMs shows that the cam is on the small side of things for that engine. However, look at your peak torque number. I'm willing to bet that the torque curve stays consistently flat throughout the RPM range.
Don't worry about the peak numbers so much.
Don't worry about the peak numbers so much.