Luis Ibarra

Recently I took my car('92 TA conv.) to get dyno tested. What a disapointing day! First let me say I have a 305 TPI, not a 350. But it's still a v-8 isn't! These are the mods I've done to it :SLP Headers,SLP Cat-back,SLP cold air induction, K&N Air filter, 52 mm. throttle body,MSD ignition box, performance spark plug wires, shift kit, and a JET stage II chip. Because I didn't get it dynoed before the mods(Stupid me), the only thing I had to go by was a '92 sales catalog I have.
It said the 305 automatic put out 200-205 hp. I figured with all the mods installed I would at least make 225-230 hp. The dyno test said 200hp!! It was run three times. How is that? Can anyone tell me if one or a combination of these mods is hurting the performance instead of helping? What should I modify next, or put back stock? Could the dyno machine be wrong?

Mark305TBI

That factory rating is flywheel horsepower. If you pulled the engine and put it on an engine dyno it probaly would be in the 225-230 range (minimum). There's a formula to estimate flywheel horsepower from rear-wheel horsepower, but I don't know what it is.

-Mark W.
'88 SC Camaro w/ 305 TBI

jcb999

That's about right my friend. The rule of thumb is engine hp * .85 for manuals and about .80 for autos for dyno jet rear wheel hp.

LT1 WS6 TAs make about 265
5.0 mustangs are about 190 to 195 depending on year
99 Mustang GTs are about 230
My GS400 was 235
Cobra mustangs are about 255-260 (96-98)
LS1 cars are 285 to 300 depending on year (and are underated)


[This message has been edited by jcb999 (edited December 08, 2000).]

super chevy

You've done all the easy mods. It's time to take advantage of the mods you have by installing a decent cam, and porting your stock intake base and plenum. If you have the funds, I would recommend pulling the heads and having them pocket ported - especially on the exhaust side.
You should see an honest 25 - 35hp improvement.

vortecfcar

that isnt a bad #, hot rod TV did all those mods and more on a TBI car and only made 183HP through a 5 speed

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91 RS W/carbed 350, Vortec heads, performer rpm, Comp cams Xtreme energy 280 grind. BFG Drag radials. 3.42 posi,Corvette servoed 700r4, ****ty stock converter
13.24@104

five7kid

iTrader: (14)

Pop Hot Rod did a dyno test (flywheel) on an engine similar to yours, but .030 over, stock TB, "performance" valve job. They got 215 HP. They then bolted on pocket-ported World S/R Torquer 305's, got 265 HP with better torque across the range.

Those heads, a better cam would help you bunches. I doubt, though, that the 52mm TB is helping you at all, and is probably hurting driveability.

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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R. 2.73 unlimited slip. Cat-back from '91 GTA, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LB9 w/ZZ3 cam, TBD heads, exhaust, paint, etc.).
57 Bel Air, my 1st car. 0.030 over 396, Weiand Action+, Edelbrock 1901 Q-Jet, Jacobs Omnipack, 1-3/4" headers, TH400 w/TCI Sat Night Special conv & shift kit, 3.08 10-bolt, AMSOIL syn lubes bumper-to-bumper. Best 15.1 @ 5800' Bandimere. Daily driver while Camaro was being put together.

mtx28

mustang GT's are 260hp and havent been to much less than that for the past 3 or so years, and the Cobra's are equal, in power, to the GM f bodies. also, after 71.. or 72, i cant remember, all power is reported as BHP, not flywheel horsepower. if their numbers(whoever said 200flywheel hp) is infact right, then their breaking the law, which i doubt is true