300 to 350 hp?

[HICKL]

I've done plenty of auto repair and motor rebuilds, but not alot of performance stuff. I have a 350 out of a 77 vette that I am building upon (stock produced about 175 hp I think). Anyway, I would like to get 300 to 350 hp. Whats it take to get there. I am taking it to the shop to get it bored .030 over and will put in some flat top pistons. Can you acheive that kind of HP with stock heads? What cam and intake would you guys recommend. Keep in mind, I want to stay under the hood using JTR mounts, so no tall intakes. I know this is an open ended question with so many ways to skin a cat. Just looking for opinions.

 

Thanks

[Mike C]

300hp is a no-brainer with a 350. For a budget motor, have the machine work done and get an engine kit from www.northernautoparts.com their high-perf 350 kit with hyperutectic pistons is $299 with everything including your choice of Crane Energizer cams. Your only extra expense will be a set of appropriate valve springs. I like the 278 for a mild street motor in a light car up to 6k rpm, 272 if 5500 is good enough. Whatever you do, do NOT get the 284 cam, just too big for your stock heads and IMO, just a POS, and the only energizer not on 110 degree centers. I ran one for awhile and so did my buddy and neither made the power they should have. I would go with the Weiand Stealth intake as it flows almost as well as the RPM, but it is lower for hood clearance. If you have the stock Q-jet, that should be sufficient for 350 hp. Hook it all up with a set of block hugger headers and 2 1/4" into a Flowmaster 2 1/4" dual to 3" y-pipe and run 3" out the back with a Walker 3" turbo muffler. If this is too loud, also use a Walker turbo tube in the tunnel. Another choice that will cost a couple of ponies is after the Flowmaster Y, do 3" back near the diff then install a 3 to 2 1/2" reducer and buy a pair of 2 1/2" 90 deg mandrel bends to run into a 2 1/2" muffler. This should be only slightly more restrictive at 350hp, but a lot quieter. The Chevrolet '69 Z/28 air cleaner will give you another 1/2" of hood clearance with a 3" filter compared to aftermarket air cleaners. It is just expensive at $90 for top, base, and paper filter.

[HICKL]

Thanks Mike, What kind of idle to you get with the 278 cam? I like a little lope, actually I like a lot

[Mike C]

The 278 should "lope" nicely about 800 RPM. At 600 RPM it will REALLY lope! Stay conservative as torque is what really zips you along in a streetcar. For 8.5-9:1 compression and the 200 cfm or so your heads will flow, the 278 is plenty big a cam. I have the 266 in my Jimmy with 9.5:1 and closed chamber heads (vs. your open chambers ~ 20 hp.) and I guarantee it would run faster now than it did in my Camaro with the crappy 284 cam. The 266 is pretty much cooked by 4500 rpm however, it would make for as sweet driving manual trans V8 car IMO, but RPM is too much fun in a light car, and the 278 should be good to near 6k depending on ability of heads to flow. A few hours with the grinder pocket porting the heads and making sure you get a good 3 angle valve job with a 30 deg backcut on the valves should really help, at least to the tune of 25 hp. I think this can be done for $1000, including the kit and machine work, but excluding peripherals (intake, carb, ignition, exhaust, etc.)