Hi folks-

I have a 91 Foxbody LX Coupe- it's nice.

It's a 306, Supercharged Fox Vortech Strim

I had a question. What can I change on the bottom end (motor) to achieve a 500 Horsepower to the rear wheel setup.

I would like to remove the whole engine, and go Natural Aspirated. Can this be done with a 347?

If you can chime in. I would like to ditch the Supercharger for now. I have a Holley Systemax intake sitting in my garage, with a brand new set of Trick Flow Twisted Wedge Heads. I'd like to have a bottom end built and put it all together-

Thanks in advance,
Mike in Central Florida

 

With nos it would be. Without nos or blower it would not at the wheels, maybe 475 hp at the crank with proper intake, heads, compression, and exhaust.

 

500 will take a healthy parts list....and probably wont be streetable from a 5.0 block motor.

 

351 Block stroked to a 408 seems to be the concensus- this is probably what I'm looking at

 

You beat me to it, it will fit fine and will be a better starting point. If you really wanted to stay 302 it can be done, if you really wanted to drop some coin you could get one of the larger bore blocks and a custom set of pistons for around a 368" if I remember correctly. Either way I would recommend an AFR head set up and a nice cam, it can be done! If you build the block strong from the beginning with around a 10.5:1 - 11:1 CR you can let it eat on some nitrous down the road when it's not enough

 

IMHO, if you're sticking with a 302/5.0 it would be best to consider going with a aftermarket block. Factory roller blocks are thin-wall castings. 500 whp seems to be a generally accepted "limit" before stock block failure becomes a given (not always true of course, and results may vary). Girdles and such only help to keep the parts from making a bigger mess if/when the block goes boom. The previous post mentioning a stroked 351 (roller cam) and associated components would be the more cost-effective way to reach your desired power level.

 

Don't forget 500whp is Going to be around 575-580 at the block, that's a lot of power for the street. Why not upgrade to a 351 forged block drop the compression and bolt a blower up? The new 5.0 coyote is factory ~412 hp at the flywheel. With hi- flowing, best stock gord heads ever, perfect factory exhaust and an 11:1 comp ratio. Even upgrading to a 347 with similar quality heads, exhaust and comp ratio won't get you to 500whp na. The corvette z06 is 505at the crank with a 7.0, about 455-460whp.

 

Build,or purchase a nice big bore 427 Windsor based stroker,as a start! Cubic inches will get you there,plus keep it easy on the street.