The Stovebolt Site Forums The Shop Area The HiPo Shop Building up a 235's horsepower?

I have a 1961 Chevrolet 1/2 ton with a 235 and a 4 speed manual. I want to make my truck a little faster but more importantly I want to have more power at speed for climbing hills and the like.

Eventually I am gonna put a t-5 in it too. I want to have power at 60-70mph. I am looking for a good all around truck and right now it is just too slow.

I am also gonna rebuild the head and have it port polished and all of that good sruff.

What gear ratio?

What kind of cam?

What headers?

What intake setup?

Ignition?

Mufflers? For that really good 6 cylinder roar!!

Other ideas??

Thanks,

Kyle

Just to play around with the gear ratio go to www.randysringandpinion.com and use their calculator. increase power, fenton headers, dual exhaust and dual carbs. change tire size to suit the gear ratio. ron

What We b OLD said, plus you might consider a Howard M4F solid lifter cam. I have that basic setup with a 3 speed w/BW overdrive and a 3.90 rear gear and 30" tires. It purrs right along at 75 mph just fine, with plenty to spare, at about 1900 rpm or so.

My 62 w/235 is mostly stock except headers, hei, O.D. and radials. 3:90 rear. 17 mpg @ 70-75 mph all day. 60-65 on the steepest hills.(Sea level, haven't tried it at high altitude)RPMs are 2300-2500 at that speed in 4th over. The O.D. and radials are key. A mild cam and a dual intake(or a clifford intake w/ a 4 barrel) will give you a little more as will increased displacement. I've been told that the porting and polishing the head gives very little gain and then only at high rpm. In other words, a waste of $ since it is expensive. The larger powerglide intake valves (1.94)have been recommended to me with a 4 angle valve job and backlash the seats.
I'm doing all the above to a stroked out 261 because I want to tow and I like the looks a hopped up inline. I'll probably stick w/ a stock 261 cam. But for just driving on the highway, the 235 does just fine.
The t-5 is a good choice for cruising and highway driving, but doesn't work out as well for towing as your 4speed would w/ an expensive gear vendors O.D. I have 7 usable forward gears. Did I say I'm biased?

If you do a little research into the 235 you'll see that it makes it's torque down between 1600-2400 rpm. Adding more aggressive cam is going to adversely effect your low end torque and have you spinning more rpm's. Now this is a 4 main engine, not a 7 main engine....why not work on improving your low end grunt and use your gearing to stay inside the near-stock power band?

I chose the latter for my 54....with no regrets. My torque cammed, fully balanced, bored .60, with some modest headwork 1960-235, coupled to a .72 OD 1985 S10 T5 running back to an 88 Camaro 3.42 diff with 29" tires, stock distributor (no high rpms needed) dual Carter/Webers and Fenton headers w/1-7/8 ID exhaust into CherryBomb Turbos, will cruise all day at 65-70 at 2000 rpms. It will drop down to 45 in OD and smoothly accelerate back up to 70 mph. I can tuck it into 4th gear at 35 mph around town and run it 65mph if I have the need and still not working the engine that hard.

The 235 is never going to be a rocket ship....the best bang for the buck is in getting the engine drilled for a full flow filtering system and the full rotational balance. Having great oil pressure at hot idle is reassuring and the balance job really smooths out the engine. In all honesty, unless you're going to go with an upgraded disc braking system, radial tires, and gas shocks, front and rear sway bars, a complete rebuild of the straight axle, roller bearings, cruising at speeds over 60-65 are not going to be that pleasant. Just the wind noise, even with plenty of cab insulation is an issue.

Kyle, you've got the right idea about doing your research before you start throwing time and money into your truck. I'm not quite sure where "Howling Timber Wilderness" is located but if you've got a bunch of long hills and you go with the T5, you're going to find that you'll be doing a bunch of driving in 4th gear. A 3.73 is going to have you wound up pretty tight in 1-4 and your 235, even tweaked, isn't going to fly up the steep hills in OD. I hope this helps you with your planning.

Dave

Good article on the 235 in the latest Street Rodder mag (this month's issue, ya may be able to read it online at their website.)

Mike

292!

292, not a bad idea. I've heard you can modify a 235 valve cover to fit. It would also be much cheaper than building up a 235.

Having had a 235 with tri-power.I suggest a single 4-barrel manifold.They weren't available back in my day.As already mentioned,the more cam you put in it,the less bottom end you'll have.

I wouldn't call the M4F Howard cam too much. I'm running one, and have plenty of torque from around 1200 well up to 4000 rpm.
Here's my complete setup,
235, 1955 truck block, .060" over, head milled .030"
TRW forged pistons, Sealed Power rings, Cleavite bearings
Howard M4F solid lifter cam, hardened vales seats and larger valves, w/cam specific springs
Mallory electronic breakerless ignition, mechanical advance, Mallory part # 29440 Promaster coil, Mallory 3RLi HyFirespark control, Pro Sidewinder 8MM wires, timing set at 15 degrees advanced.
Induction is Offenhauser 2 carb intake, no heat, w/ dual Holley 1904 carbs, #54 jets. K&N air filters.
Fenton cast iron headers, 2" stainless dual exhaust w/ Walker CJ7 Jeep mufflers.
SM 318/BW overdrive trans, 3.90 rear gear, 30x9.50x15 tires.
This is in a 3200 pickup, I run at highway speeds very comfortably at about 1900-2000 RPM.