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MG MGB GT V8 Factory Originals Technical - 300 rear wheel hp recipe

Hi all,
I am hoping to make 300 on the ground in order to come up w/ roughly 8 pounds per pony power to weught ratio. These are the engine components I intend to use: Rebuilt stock 87 5.0 Bottom end, GT40 aluminum heads, Edelbrock 600 CFM carb and intake manifold, RV cam, shorty headers (if they'll work right out of the box), and 2.5 inch dual exhaust back through a pair of two chamber Flowmasters. How close should I be? P.S.- I am not opposed to a 75 or less hp wet nitrous unit to bump me over the edge. Thanx
Geoff

Won't happen. The stock bottom end has too low of a compression ratio to really get some juice out of it. You need to bump the compression a few point to get what you want. Why do you want GT40 aluminum heads? For minimally more you can get some REAL heads -- AFR's Twisted Wedge, etc. I have a recipe sitting here for 455 natually aspirated horsepower (at the flywheel)from a 302. The key components are good compression, GREAT heads, and the right cam.

Justin
Justin

Geoff,

Check out http://www.edelbrock.com/automotive/index.html
Click on Dyno Test results.

Edelbrock make good packages proven to make HP.
If you have aftermarket pistons with valve reliefs, the RPM package will produce around 367 Flywheel HP, that's with only 9.5:1 comp ratio !

Good Luck

Pete
Pete Mantell

"Edelbrock make good packages"

Hey, Pete, you're in America now, that should be Edelbrock MAKES good packages! (In England, a company name is considered to be plural; in America, it's considered singular).

Just kidding you, of course, but it sure sounds funny to an American ear (just as I'm sure the singular form sounds funny to you).

Geoff,

Go to your local Ford Motorsports dealer and ask for part number M-6007-XB3. For $3,195, you'll get a complet crate engine which has been dyno tested to produce 375HP. All you need to add is the intake, exhaust, starter, etc, and you are done - the same pieces you'd need to add to any engine you might buy. No need to mess around with bits and pieces, machine shop work, or assembly.

Shop around and you can get it for less $$.

Justin,

The GT40 heads are not bad, but there are better ones available. There is not a lot of difference between the various heads as far as horsepower is concerned, unless there have been serious imporvements in the last couple of years. How about writing up your recipe for 455HP and submitting it to the Newsletter?
Dan Masters

I would write it up, but it's exceptionally simple:

Horsepower: 455 @ 6100 rpm's
Peak Torque: 398 lb-ft @ 5500 rpm's (above 300 lb-ft from 3000 rpm's till redline)
Engine: 302ci
Heads: AFR 185cc
Compression: 10:1
Carb: 650 cfm speed demon with 84/87 jets
ignition: msd digital 7, 36º timing
Cam: Comp cams extreme energy hydraulic roller 282 (this cam is definitely a lopey idle)
rockers: 1.6 rockers
Exhaust: 1 3/4"
manifold: Victor Jr
Fuel: 92 octane

Power comes on relatively early (285 lb-ft of torque at 2000 rpm's) and stays on through redline. Very neat motor. If I were putting a 302 in my B, That's what I would consider. =)

Justin
Justin

Justin
Come on, you drove Barney, and it dyno'ed at 300 hp at the rear wheels !!! And its still running way too rich. Geoff, I would go with either the Holly or Demond
Steve Carrick

You're right, it was absolutely incredible. There's no denying that, and I'm not trying to say he shouldn't have 300 rwhp in a B, I'm just saying his recipe wouldn't make it. ;-) 455 flywheel hp has to be somewhere around 370 at the wheels. I wonder if that would twist the body?

Justin
Justin

"...455 flywheel hp has to be somewhere around 370 at the wheels. I wonder if that would twist the body?"

Only if you hooked up!

Dean Lake

Justin, that is a tall order for a NA 302. Talking a pretty much a race engine set-up that may be less than enjoyable for cruising or daily driving. Not that it would not be fun once in a while, but not something to drive to work on the freeway daily like a stock 302 wih ~300-350hp at the crank. Just rememebr a STOCK 302/5.0 only produced around 215-275hp at the crank from the factory, the mustang guys hop thiers up a good bit to get the 300-350hp mark.
Larry Embrey

This thread was discussed between 31/03/2004 and 02/04/2004

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