ITS Ford Mustang(s) Build - Stripper Stang Part II

[RedMisted]

Dyno time is set for noon on Monday so we'll wind it up and see what its got. Did you ever dyno your 99 stock?

Yeah. It was a pathetic 143whp stock.

[Ron Earp]

Yeah. It was a pathetic 143whp stock.

Was this on a Dynojet???

[Ron Earp]

Dyno pull today with a Dynojet, the same one we have been using for all of our race cars.

Any bets on the outcome?

I am guessing 126 rwhp and 182 rwtq. Not sure at what RPMs but it'll be low.

R

[RedMisted]

Was this on a Dynojet???

Yes. And on a hotter than hell/stickier than flypaper humid day, if that makes a difference.

The engine was the original, and I remember when I bought the car that its acceleration was anemic compared to previous rentals that I'd driven. The tuners were able to get it up to a respectable 158whp. Now with all the peripheral mods and the like, the replacement engine gets about 195whp.

I think your estimates are in the ballpark.

[Ron Earp]

The Dynojet spit out 125 horsepower and 189 ft/lbs of torque. The A/F was not so good at WOT and I bet with a bit of tweaking that it'd end up at 130hp and 192 tq, so that is what I'm calling it. Torque good, horsepower is a bit weak but the curves are broad so I think it has potential. Have to think about it.

[RedMisted]

The Dynojet spit out 125 horsepower and 189 ft/lbs of torque. The A/F was not so good at WOT and I bet with a bit of tweaking that it'd end up at 130hp and 192 tq, so that is what I'm calling it. Torque good, horsepower is a bit weak but the curves are broad so I think it has potential. Have to think about it.

I think your hp is just about right if you factor 15% driveline losses. That torque number looks pretty impressive, IMO.

[CRallo]

Wowsers that's a stump puller!!!!

BUILD it!!!

[Ron Earp]

Yes I think I will build it. It appears to be making an honest 140 crank hp and I'd expect a 72k mile car in good shape to come close to stated factory power. Interesting that it is "only" 17hp down to the ITR Mustang, but it is different Dynojets in different states.

Next step is acquiring a spare motor to be used at the IT base engine and start building. Engine build costs for this engine are insanely inexpensive. Parts are easy to come by. There will be "big money" spent on the exhaust but the other costs - pistons, valves, machine work - very affordable because it is a domestic engine and down here in NC there are many shops that thrive on this sort of work.

[RedMisted]

The engine was the original, and I remember when I bought the car that its acceleration was anemic compared to previous rentals that I'd driven. The tuners were able to get it up to a respectable 158whp. Now with all the peripheral mods and the like, the replacement engine gets about 195whp.

Tq on the original stock was 177. On the replacement, tq is 211. I think with a good IT build, another 15whp is not out of question. As for tq, the gain may not be as much...

[Ron Earp]

As advertised dyno plots for the engine. This is a bone stock example, still breathing through the stock air cleaner and out through the stock cat and single pipe exhaust. 72k original mile motor as well, with stock ECU and so on.



The torque peak is very low in the engine leading to a low RPM for peak horsepower. More ideal for a truck motor, or automatic equipped car that spends most of its life below 3000 RPM. But, we've seen engines just like this respond well to IT build rules. In fact, at the dyno shop they have a 97 Mustang V6 plot with some large primary long tube headers, dual exhaust via Ford Mustang GT, and cold air intake, with nothing else, that is up about 23 hp but more importantly the hp peak hits around 4700 RPM. Torque is close to the same at 199 lb-ft at around 3500 RPM. I bet with some real attention to all the IT-preps, particularily the exhaust side of things where Fords are generally challenged, we could shift the torque curve considerably.

All in all very promising. I think the engine will respond well to a full tilt IT build. And the chassis is a quite known quantity, which is to say, it isn't fantastic but the warts have long been exposed and it can be made to work reasonably well for what it is.

Might have to build it.

[benspeed]

Go for it! I was contemplating this car before selecting the 968. Could be a winner! Keen to watch the build. Heck, you can always drop in a V8 to race in another class if you feel like it :-)

[RedMisted]

I agree with your assessments, Ron. People have been telling me that my engine will probably make the 25% percent rule, or whatever it is, look conservative. Can't wait to build it.

[Ron Earp]

Go for it! I was contemplating this car before selecting the 968. Could be a winner! Keen to watch the build. Heck, you can always drop in a V8 to race in another class if you feel like it :-)

This flexibility is what creates some sense of security about the car for me. I’ve made the decision to race a Ford, the only Ford choice of interest to me is a Mustang, and this platform lends itself to a variety of venues.

SCCA AS
SCCA ITR as a V8 (5L)
SCCA ITR as a V8 (4.6L)
SCCA ITR as a V6 (would require sheet metal changes)
NASA CMC
NASA various classes

Many options from which to choose if the ITS V6 build didn't pan out.


I'm heavily researching the suspension options now and will start collecting parts soon.