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Dyno Day......numbers off?

15K views 180 replies 23 participants last post by  pimprn 
#1 ·
So did a dyno tune on my car. I tuned the car.......i made 573awhp on pump and some meth, at 30psi. I was expecting alot more.......

My turbos are twin gt3076r with .48 exhaust and .60 on compressor could the .48 rob that much power? Is it cause im so much above sealevel that the air is this thin that its that much of a difference?
my heads are ips race heads 1mm over so theres tons of flow
90mmintake 90mmthrottle body

The dyno was a dyno jet, any gurus suggest anything thanks.
 
#4 ·
Well I did not pressure test it I don't think there is boost leaks everythig seamed really tight I welded most joints together but the silicone ones could be leaking ill have to check.


My intake is speed density so one turbo has just a aem dry flow filter and the other has the sale except with a small tune so it gets air over transmission. So no maf..... As for the intake plenum it's a pnt 90mm intake the big one bigger then the dr one and better for aerodynamic flow....
 
#6 ·
My exhaust is the mr2 and 2.5" 02s..... How would you pressure test a speed density setup?
 
#8 ·


theres my car.......
 
#10 ·
should i pressure test to 40psi cause thats what i plan on running on race gas
 
#11 ·
im useing aem series 2...... Can i post the map? i can just email my log.
 
#13 ·
the 4.5" thick one with 3" in and 3" out. Although i might add my hydraulic tensioner failed the other day and timing jumped a bit but my car was still able to boost to 30psi and it purrs.......

So i put in a new OEM hydraulic tensioner a week ago and same shit happened on dyno so ordered another one...... and hopeing it still runs and boost so that means my valves are good. Still gunna do a compression test to make sure. Wonder if my car is running good with bent valve but doubt it. I called ray he said if its running on all 6 im fine.
 
#15 ·
What happened was my hrdraulic tensioner failed, replaced that a week ago then dynoed the car the brand new oem one failed while on dyno.

im just saying after the first time the old hydraulic tensioner failed AFTER i installed the new on it boosted to 30psi so what im saying is that the valves are good. And im hopeing there good this time.........
 
#16 ·
you could technically see 30 psi with bad valves. you would need to do a leak down check to verify the valves. or if they are bad enough you could see them with the valve covers off. either way the problem is either in the tune map, boost leak, or both
 
#17 ·
I pulled cover off didnt see any rocker arms or anythign out of the ordinary...... I think doing a leak down compression test is best way to eliminate this problem.

Tune is fine man the car hauls ass dont get me wrong.

Im thinking my problem lies in these three catigories :
Need to degree cams in
Possible boost leak
Or bent valves :( <------FML if thats it possible part out if this is the case cause i have had enough of this shit. Why wouldnt they us ea timing chain....
 
#18 ·
tune could be fine. just really, really conservative. thats why you should post up your ignition map.

cams out of degree can make a deifference. worth taking a look

boost leak is a no brainer

i would think that you would have noticed something off about the car if the valves were bent. it wouldnt be running quite right.
 
#19 ·
ill post my timing map right now on 30psi with pump +meth.
 
#22 ·
Of course its good i was tuneing :) as soon as i see 1 volt of knock like twice or so id back it off do a another run with timing backed off and see if it persists. Or if i didnt see any hp gain id back it off......Which one pull i added 2 degrees and it actually dropped my boost off and lowered my hp by 1 haha...
 
#24 ·
like yah my tune i can squeeze prolly 20-50 more hp but to be 100-150 off somethigns fked
 
#25 ·
You need to do 2 things. One figure out why your car keeps eating tensioners and two..you need to do a leakdown to make sure you dont have issues. Get a good tester and post results. When are you seeing full boost and when you pressure test. .BE CAREFUL. ..if anything pops ar 40psi..well..use your imagination. .lol

Post the dyno graph...and boost plot. You never mentioned mustang or dj. If those are mustang numbers then its solid numbers.
 
#26 ·
It's dyno jet and only have a max hp speed graph??
 
#28 ·
its in my email send me ur email ill email it to you? i dunno how to post it from email.
 
#31 ·
I don't understand what you mean ? I did a pull on dyno in 4th and dyno said 573???

Gunna do leak down test I'm sure I have bent valves....I can't think of why cause my engine load line in log on that pull is a bit squiggly meaning the engine was bleeding pressure off a bit....
 
#32 ·
Dyno numbers can be corrected to show what you would make at sea level and make dynos comparable at various temperatures. If you post the graph, it should answer the question.

What is your elevation?
 
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