The Stovebolt Site Forums The Shop Area Engine Shop 235 performance

Lets say you wanted to build a full pressure 235 that would be a daily driver. The goals are for the truck to have the most performance possible without sacrificing the reliability needed out of a daily driver. What would you do?

I would go with a moderately agressive cam, Howard M4F grind or more, solid lifters, aluminum timing gears, aluminum pistons, shaved flywheel, a good bore and balance job, Pertonix ignition, Delso 10si alternator, electric fan, Carter AFB and a 4 barrel manifold and fenton headers. That will be nice and healthy, reliable, and outlast a stock build. It will be spendy, though.

I just built a '60 235 very similar to what 4on describes. Doing the job correctly will cost between 2500 and 3000 dollars. Powerband is idle to 4000 RPM. Max cruising RPM is 3200. Roughly 180-200 HP and 250-300 ft/lbs torque. Not blindingly fast, but you'll get mucho cool points at the cruise-ins.

chip

Yes like Chip says, each time you do it will be around 2500 to 3000.

Another carb option is the dual Holley-Weber progressive 2 barrel carbs. They will give you roughly the same performance with a little better torque curve in the bottom end. And dual carbs look cooler, plus giving you better fuel distribution to the cylinders.

I have a .30 over '56 235 w/ "848 head" (last 3 #'s of the head=higher compression), Fentons, 1 Holley-Weber, HEI ignition, '62 3sp+od, '57 3.90 rear (final drive in od, 2.73). I have split exhaust all the way out, no balance tube, 2x30" glasspacks. Mellow sound, can rap if I want to, good power to get up on the on ramp, good passing power. Stock brakes, everything new.

I took a 1500 mile round trip this summer, averaged 18 mpg. Oh yeah, this combo is in a '49 3100 with LT 215 85R 16's. If you don't haul heavy might as well go to a "P" (but I don't think there is a P out there that is as tall as the aforementioned LT's @30.38") for driving comfort. I'm thinking of going to 2X2bbl H-W's on the Edmunds waterheated manifold I have hanging in the garage...but why mess with a combination that work's great? Yeah, I'll do it; I have to see what's on the other side.

180- 200 hp from a 235 ?That's a bit of a stretch,lol. More like 150 or so for one like described above.

Hey its possible... The production 235 vette engine had 150 HP, and it didn't have a 4bbl, HEI, a shaved head & block and polished head ports.

Hey TonyM, hows them shorts feel?

Oh, if you are going to do that to a 235 you might as well do it to a 261. Then you get stronger rods and a larger bore, and full flow oil filtration, but pistons may be harder to find. The rest of the work won't cost you any more. That is my plan. My 261 is stock and good right now, and I have a spare 235 in the garage to drop in while I send the 261 to the machine shop.

The 261 had 150 HP stock, and wakes up more with just better breathing. The corvette grind was used on the stock 261 cam and it is still pretty smooth, you could go with a much more agressive cam and still have a good idle. I like mine a lot.

In the May 1955 Hot rod magazine,a performance shop dyno tested a 261 engine from stock to a complete full race engine in 9 stages. The stock HP was 114 at 3500 rpm,torque was 200 at 2500 rpm,serious road rocket power.A hot cam,split exhaust, 2 properly set up carbs and more compression gave 157 HP at 4500 rpm and 237 lbs-ft of torque.The maximum out put engine which was considered the limit streetable performance( ported head,bigger valves, big cam ,more compression. was 197 hp and 268 lbs-ft of torque at a low 2000rpm and slowly tapered off to 245 at 4500 rpm.So lets figue the guys dyno was accurate back then and that present Stove engine devolopment isn't exactly state of the art, so you can get around 170 hp on a moderate on a 261 ,the 235 would be 155 or so in the same state of tune I guess.Other than some old 216 dyno tests, I' ve never seen any other published dyno work on a 235/261.I think a custom truck mag did a 235 build a few years ago, maybe that has something more.

Do go with the Howard cam and the Fenton dual exhaust. I suspect the Holley/Weber, either single or dual, might be better for a daily driver. A 261 is a bit bigger, treu, but the 235s are pretty common, so you save a few $.

I wouldn't shave the flywheel. Off-the-line torque is nice.

Another option that would work well on a 6 is a small turbo. 8-) Emphasis on small....

Cheers!
George

I have been dreaming about building a high power
chevy 250 with turbocharger and ram air intake into a custom fuel injection,
12.5-1 compression, forged pistons, mabe "strike it rich" and add twelve port head
triple 2 inch exaust pipes hooked to cut outs and then routed to nice qite muffeler and tail pipe
forged balenced crank, connected to a
NV 4500 5 speed overdrive