The Stovebolt Site Forums The Shop Area Engine Shop Rebuilding/Updating a 235 engine

Guys- hope this topic not beat to death- I've been driving a '54 Chevy 3100 pickup some 15 years now- as my exclusive vehicle- don't own a modern one. Has stock 235- rebuilt once, slight overbore, and hooked to original 4 speed granny. I'm starting to blow a little blue smoke, and she leaks a lot of oil, tranny is noisy as can be, and she's headed for at least a ring job and valve job. I do not want to rep[lace this with a crate engine- do not intend to street rod. However, realize some improvements would be worthwile. Question is, what are they? Would electronic ignition be good, add an offy manifold and second carborator- or update to a duce?

Full flow oil filter. Go to the tech tips for instructions. M4F cam. Cast iron headers or get your's split at Kansas Kustoms. Carbs, go with duals, either ones or progressive twos. Electronic ignition of some sort. Hardened exhaust valve seats. Umbrella style valve seals. Find a 848 head, higher compression. If you really want to add more oomph, get the head ported and shaved, and balance the crank and rods.

If that isn't enough, get a 261, put in a full race cam and the dual progressive two carbs. With the mods listed, you will have a 200+ hp engine that is very streetable, and will rev to 5,500 rpm.

Microbe-

Welcome to the Stovebolt! Plenty of help around this garage.

The first question might be: what do you want in the end? Do you want more performance or a daily driver with similar characteristics, but less blue smoke. How much of a factor is cost? Are you mechanically inclined (do-it-yourself) or are you farming this out? Is this the only part of your truck you want to change? These questions may help you focus on simple engine machining, replacement, or upgrades.

OK, with a handle like "Microbe" I'm intrigued. What do you do for living?

Microbe= I'm a clinical microbiologist by trade, career govt, 22 years Army special forces, now working VA. I'm only interested in improving performance as daily driver, no intention to upgrade steering,suspension, brakes. A little more pep would be nice, but consistant with above requirements. Certainly not replace engine, change cam. Quieter, smoother, more fuel efficiency. I'd send the engine out for rings, seals, valves- would also include and additions. BTW Engine has never, repeat never had any kind of oil filter. Why add one now?

Microbe-

Thanks for insight. Used ot teach Microbiology. You're among friends!

I'm more the hot rod type, so I will defer to other inliners for help in the best way to gain the performance you seek. After 50+ years, some overhaul might be appropriate!

If it is your only vehicle, rebuild it stock. Multi-Carb setups are cool to play with if can afford the downtime for tuning carbs. Split manifold will give the illusion of more power because of the noise, but minor, if any power gains. A Petronix point conversion for your distributor is nice if you do not like dealing with points.

Find a machine shop that is familiar with 235 rebuilds. These days they are becoming scare. If the machinist frowns/winces or responds with, “What is a 235”? Run like crazy. As simple as these engines are, an inexperienced machine shop can easily screw it up.

Have new bearings installed in your transmission, that will quiet it down.

Thats my 2 cents worth of practical advise.

The oil filter will extend engine life. When these engines were designed filters were in their infancy and were considered a luxury. Non-detergent oils were used, which allow the grit to settle in the bottom of the oil pan, where some of it stayed. The detergent keeps the grit in suspension so the filter will trap it. The filter is worth every penny spent by reducing wear on the engine. The later 216 and the early 235 was equipped for a bypass filter, which was an accessory or added on as an aftermarket item. They only filtered about 10% of the oil that was pumped through the engine, but did help a lot in getting rid of the grit.

The modification is rather simple and is best done when rebuilding an engine so that metal fragments can be washed out before running the engine.

Yup , the oil filter is a must , even if only thr bypass one and change that oil & filter every 3,000 miles when hot , no BS ! .

I'd recommend a 261 cam , it goes right in and will help the stock engine breathe easier , more power & torque the result , always _new_ cam never _ever_ a re-ground one and new lifters too

Have the rods balanced along with the crank and flywheel , they're not well done when new , this will add a smoothness to the engine that must be experienced to be believed .

Magnetic oil drain plug of course ! .

Split manifolds _do_ help , not an illusion , I have a single Rochester B carby and a split exhaust manifold , it cracked so I replaced it with a single , I can feel the loss in power when I'm towing or hauling scrap , full loads .

I have an Offy dual intake manifold I'm going to put on one of these days as it helps power and fuel economy too if you keep your foot out of it , once set , the carbys _don't_ need fiddling nor adjusting . that's an Urban Myth perpetuated by folks who don't work on multi carby set ups .

Have fun , don't fall into the 350 trap ! .