racebum

Question: Just how much difference is there between a dynojet and mustang? when i last dynoed my car it did 354rwhp and 357rwwtq on a mustang. what exactly is that on a dynojet and at the flywheel for that matter {6spd car} for a little .040 over 350 with 180cc heads it does seem to fly. going to 1/4mile it soon since i can finally hook up with the new tires.

Aurora40

FWIW, my car in the same state of modification made 385 on a Dynojet dyno, and 370 on a SuperFlow dyno. The SuperFlow is an eddy-current brake dyno like a Mustang. Though obviously it's a different brand so who knows.

vader86

Roughly 12-15% difference usually.

Zix

On the Mustang Dyno in my area the operator told me that roughly 365 RWHP on his Mustang was equal to about 420 RWHP on the Dynojet he used to work with. However this may vary slightly from dyno to dyno.

black_89_vette

I have heard around 10 % difference.

So, if you're making 354 on a Mustang, it (by rule of thumb) loosely translates to (354 + 10% = 389 rwhp).

I plan on using both this year to see the difference.

racebum

that's one hell of a healthy 350 no matter how you cut it. the combo is
TPIS miniram
52mm TB
180 CC Pro-Action heads, 262@.500int 201@.500exh
comp 224/230 .502/.510 cam
987 springs
10:5-1 compression
speed pro forged pistons
eagle rods
scat 9000 crank
cheesy headman headers
true dual with x-pipe to borlas
chip was done by some guy named ed wright

when i first bought this car is ran like hell cold, did the heated 02 with the 3 wire and the MPG went up and so did the cold start. best $40 i spent. 25-27mpg on the freeway no problem. anyone else have this combo or know what they make on average?

Overboost

dyno jet sucks.
the numbers are not accurate.
mustang dyno will break your heart (and ego) but give you closer to what you are really putting out at the wheels.
a dyno jet will give you a bigger number because studies show, people want bigger numbers on thier dyno sheets. (size matters?)

aboatguy

Going against a MUSTANG Dyno for round II sometime soon!

dclafleur

Here is a bone stock '85 on a Mustang Dyno, pretty darn accurate numbers in my book. I can't help but think the dynojets exagerate the numbers a bit.

bjankuski

This question has always interested me because I have never used a Mustang Dyno but I have had at least 100 runs on a dynojet and probably 50 runs on a superflow dyno in the last 5 years. (I test alot of combinations and alot of cars) My experience has been that the superflow and dynojet numbers are very close to each other. I have a modified 1988 Firebird with a 350 in it that I have dynoed many times. In the last two years I have made no changes to the car and run it on a superflow dyno and a dynojet dyno and it has put down the exact same number (382 RWTQ and 346 RWHP). Just this year a new dyno shop opened up that has a mustang dyno and I used it to tune a buddies car last weekend. I was interested to find out how his power numbers on the mustang dyno would compare to the dynojet numbers. So I took my 1988 Firebird over to the mustang dyno today and ran it to determine the difference. My Firebird put down (351 RWTQ and 325 RWHP) on the mustang dyno. That is a difference of 6.4% peak to peak on the HP and 8.7% peak to peak on the torque. Why were the percentages between the HP and torque different?? I do not know but I did determine is that this particular mustang dyno read lower then the dynojet by 6.5% to 8.7%, closer then what I expected. In all cases the data was corrected to standard temperature and pressure and the air/fuel ratio's were similar.

racebum

when i first bought this car it had 113 heads with new valves and some minor port work. did 322rwhp on the same mustang. the pro action heads were my doing and netted a nice gain and brought the compression down half a point. nice and 91octance friendly on hot days now. what combo did you use to hit the same HP in that firechicken?

bjankuski

Racebum, This is the firebird combination.

1988 Formula 5.7L/6sp 3.91 gears, SLP cold air kit, MAS gutted, TPIS air foil, TPIS AFPR, Superram, MAC headers, Mac under drive pulleys, MAC cat back, Relocated MAT, E-Tec 200 heads, SDPC Vortec manifold, ZZ-409 cam.
Best ET 12.17
Best 60 FT 1.754
Best MPH 111.87