Hope this is the right forum, have a 14 mustang with roush 2.3 tvs, 82mm pulley, cai, fuel pump booster, aftermarket tune for 91 octane, and cat deletes. Boost is about 6 then drops to almost zero at 4500ish and builds to 8, no idea where to start. I'm used to old overhead valve engines. Car has never ran as good as it should have, best time is 12.4 @ 116. There is no residue on pulley from the belt, and the clutch isn't slipping. I tried to go through the tunner, but they said it couldn't possibly be their tune and the stratagy code didn't matter. Any ideas or suggestions on where to start would be great. Thanks
Coyote 2.3 tvs low power
- Thread starter Craig14
- Start date
Altitude of track and corrected density altitude on said run ? If its at lost creek raceway the starting altitude is 5265 FT now add in humidity and some heat from the day. Sounds normal to run 12.4 @ 116 there
part of that sounds true,but it sounds like hes loseing boost having boost issues, 12s with a tvs sounds horrible, they run that stock / bolt ons, tvs cars run 10's and 11's some in the 9's, sounds like he has a problem not just altitude, i can see loseing some et and mph, but tvs cars seem to run in the 130mph trap range and 10 second ets, i dont see him loseing a good 10-15+mph and pretty much about 2 seconds on 1/4 et just because of altitude / elevation
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So stock bolt on 5.0s run 12.4 @ 116 with a DA of 6000 plus feet ?
Do you run at altitude? If so what do you personally run and what was the DA.
Now I just had a friend get a brand new 5.0 6R80 car with a Roush phase 1 tune and Roush blower lay down 460 uncorrected horsepower with the 85 MM pulley he put on the 80MM pulley and made 500 uncorrected HP. CAR weighs 3795 without the driver 4000 plus with driver on drag radials he just ran 11.97 @ 118 at Bandimere speedway, He made 9 PSI of boost.
So I want to see these bolt on only 5.0s run that up here.
It sounds to me like the boost bypass valve is not working correctly.. Replace and haul ass!
doesnt sound that off on et/mph for that power at altitude. someone said you were at 500whp?
Im going to state the obvious....the fact you said you are seeing zero boost at 4500 rpm with a TVS sounds like the problem to me....and sounds very odd. Do you feel that in the seat when it reads low boost?
Another dumb question - have you had the car dyno tuned?
Im going to state the obvious....the fact you said you are seeing zero boost at 4500 rpm with a TVS sounds like the problem to me....and sounds very odd. Do you feel that in the seat when it reads low boost?
Another dumb question - have you had the car dyno tuned?
A 12.4 @ 116 at altitude of say a DA of 6500FT would at sea-level be quicker than 12.0 it would be in the 11s. All things being equal.
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02blackfoci
New Member
when you say cai which one? jlt's have been known for issues and the roush closed air box keeps the boost lower than expected. It could be a few other things as well but those would be my first two things to look at. next would be the tune. cam timing would play a pretty decent part in how much boost a motor makes as well. you could try to send shaun @ aed a log and see if he would look at it for you. I'm not sure he will but it wouldn't hurt or you could send lund one as well.
I'm running almost the same set up. Roush TVS, 82mm pulley, factory cats, JLT CAI. We made 600RWHP and 500FT/LB TQ on a cool Michigan morning. Unfortunately I don't know anything about altitude so I can't pretend to know how it effects HP and boost. I was consistent at 9.5lbs boost, I'd definately look at the bypass and vacuum lines. Good luck.
I know guys with tune only on stock tires running 12.30-12.50's autos
Check the Boost-Bypass Valve
I just bought a 2017 GT A6 with a 2.3 rousch 80mm that ran high 11's in much better air but after I had it tuned it picked up over one full second 10.68@128 on my factory 20" rims and a drag radial so if you want to gain a lot of power contact Ken @ palm beech dyno and have it retuned
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