Finally got the car dyno'd...

[Lucky D]

First of all, I hope the above pic works (dyno sheet).

First run after the install, she was having detonation issues @ 4500rpm so had to cancell the run.
GTR said it was Vortechs chip, Vortech said it was a fuel issue. Well, long story short, ended up putting in the Walbro 255lph pump in the tank and seems to have solved the issue, for now.

So, STOCK 96 Mustang Cobra with a Vortech V2-SC/ aftercooled, pulled a best of 384.82rwhp and 359.99tq @6300rpm with a conservative (and safe) 6.37lbs of boost.

I think these cars stock pull about, what, 265ish? I figured with about 40 hp loss through the drive train, that puts her 424hp at the crank?

Does this sound about right to you guys?

I am very excited, despite wanting 400rwhp but why push it?

But, up top she seems to "sputter" a bit. Almost like she's being held back as if she's misfiring, I'd say 5500rpm on up, give or take. Any ideas? Could be anything I guess, Should be smooth as butter. Restrictive exhaust, fuel rails, injectors, MAF, possibly detonation, coils, all come to mind. This helps me realize, why so many people change all these things.

What cost effective enhancement mods could I compliment this set up with, and keep her real safe?

 

[Cookieman00x]

very nice, 400rwhp shouldnt be too far away

 

[reddog4063]

120rwhp on 6lb is very impressive, now get some bolt ons and you'll be past 400

 

[JWThompson]

nice numbers.......bolt-ons will be awesome for reaching over 400hp.....good luck....as for missing in higher rpms what is your a/f like?

 

[Chrome98Cobra]

If you have the aftercooler you will be safe at 10psi with a safe tune, if you dont wanna run 10psi I would for sure bump it up to 8psi. Right after the S trim install on my Cobra, non after cooled at 8psi and It put down 395Hp and 319tq, so if you run 8psi you will for sure be over 400Hp

 

[94CobraPace]

Looks on the dyno you are going lean on the top end. Did you go to a colder plug gapped at .035"?
Nice numbers BTW.

 

[Bullitt66]

Nice, i hope my Cobra follows that path...

 

[97snaketrplB]

It's leaning out significantly above 5500. You may be pegging the MAF, maxing out the injectors, or both.

 

[Sergio]

nice numbers

 

[Lucky D]

They left the t-rex on along with the Walbro saying it will act as a bottleneck, letting the t-rex do its job with the stock injectors and FMU.

If its running lean up top, should I take the t-rex pump out and let the Walbro do its job? Would that be to much?

Would a chip and custom tune solve this?

Thanks =)

 

[midlifecobra]

I have a v1 with aftercooler runing 10psi and I am at 459rwhp.

 

[97snaketrplB]

They left the t-rex on along with the Walbro saying it will act as a bottleneck, letting the t-rex do its job with the stock injectors and FMU.

If its running lean up top, should I take the t-rex pump out and let the Walbro do its job? Would that be to much?

Would a chip and custom tune solve this?

Thanks =)

You'd need to have a tuner pinpoint what the precise reason is for the leaning out, but it's getting pretty lean up top on that dyno sheet (around 13.5:1). That's significant enough to warrant a change of some sort to try and get the A/F back into range.

 

[DOHCscreamer]

does the aftercooler use engine coolant or does it have a seperate circuit and heat exchanger other than radiator? if it uses intercooler, and i'm no expert, but it seems to me that with only 6psi boost the air to water intercooler probably isn't helping at all. and given the pressure drop due to pumping losses through the intercooler, it may even be hurting. what do you guys think? just some thoughts from someone with no experience.

 

[Cobreezy]

Newbie here, this site is way more helpful than what I usually go to. Anyways, sounds like the same problem I was having. I've got a 98 Cobra with a Vortcech S-trim and the usual bot ons. After installing an Anderson Power Pipe, I started noticing a drop in performance when I'm up in the 5000+ rpms. It was backfiring and felt as if I was redlining. I was wondering also if I was leaning out. But before I thought about bigger injectors and a 255 lph in tank pump, I dropped in some NGK TR6 spark plugs, gapped at 0.030" and it started running like a champ. Hope this helps!

 

[Chrome98Cobra]

Newbie here, this site is way more helpful than what I usually go to. Anyways, sounds like the same problem I was having. I've got a 98 Cobra with a Vortcech S-trim and the usual bot ons. After installing an Anderson Power Pipe, I started noticing a drop in performance when I'm up in the 5000+ rpms. It was backfiring and felt as if I was redlining. I was wondering also if I was leaning out. But before I thought about bigger injectors and a 255 lph in tank pump, I dropped in some NGK TR6 spark plugs, gapped at 0.030" and it started running like a champ. Hope this helps!

Please tell me you got a retune after the power pipe

 

[JohnsMyName]

Sounds bad-ass for the psi your pushin.

High end problems? May sound a little rudamentary, I'm no expert but I agree with 94PaceCobra, did you check your plug gaps? It could be that easy. Your tune-shop should deffinetly know about that stuff, ask 'em anyway though.

High end issues from my experiance are ignition related, especialy @5,500 rpm if it where the imrc's it wouldn't it start around 3,200 rpm's? Maybe your runnin a little hot/cold?

Anyway, just my 2cents, like I said I'm no expert. Good luck bro, John.

 

[Lucky D]

The plugs in the car when I bought her were fairly new so the shop re-gaped those (their recommendation).

I've got the receipt for the plugs from the last owner, from a Ford dealer (probably Motorcraft plugs) but can't confirm until I call Ford and give them the part #on Monday. Part #AGSF*32F*MF4

This might be a dumb question, but I need to ask...

How do I get the car to 9lbs of boost? Change the blower pulley right?

I'll call GTR Hi Po tomorrow and ask them some more questions regarding the boost/ aftercooler equasion. Like mentiond above, the whole idea of the aftercooler is to be able to run a little more boost without worrying about detonation.

Thanks everyone!
-D

 

[Chrome98Cobra]

If you put on a anderson powerpipe you will probably pick up 2lbs of boost, and power pipes are nice because you get more boost without spining the blower any faster.
Mark

 

[Chrome98Cobra]

Oh yeah and I would definitely pick up a set of NGK tr6 plugs, thats what I have in my Cobra with the gap set at 35