Technical 235 Chevrolet Reliability/Modern Upgrades?

Hi guys, I had a few questions regarding modifications in regards to reliability.

I've got a 235 straight 6 out of a 1954 Chevrolet car in my 52 Styleline. I was wanting to keep an inline 6 in the car for the smoothness, but wanted to use it reliably for regular driving. Also of note is that the car was converted to 12v in the past and is running an alternator in place of the generator.



Some modifications I've considered are:

• Replace draft tube with PCV valve/system(To cut down on under-car mess/contaminants entering engine)
• Hardened valve seats (For Unleaded gasoline)
• Fuel Injection (Such as Atomic EFI or similar that takes the place of the stock carburetor, for easier starts and less chance of ethanol damaging the fuel delivery system)
• Electronic fan on the front of the radiator to maintain cooling
• Aftermarket, aluminum radiator for additional cooling

Some of the questions I've had are:

• Can this engine be upgraded from flat tappet to roller style cams?
• Does there exist a single-barrel fuel injection conversion I could put on this engine?
• Are there other internal upgrades that can extend the life of the engine or improve reliability that I should consider when re-building this engine?
• If I was to swap to a different Straight 6 engine, what would be a good engine and why?

 

Try using the search funktion for
Stovebolt six
and The dedicated 261 thread

They arre too good threads on Six matters.

- Draft tube to PCV, I see no reason for it to Work, and it should be a good upgrade to make.
- Hardend valve seats, aint a bad idder, but make sure yor do it in a motor you wonna keep. It will cost you some Money to do.
- Yes its possible to change to FI, but for what reason? Twin karbs of a good qualitu should do nicely.
- I see you on the fan issue, it will wor but so will a mech. fan that came with the car. I acyualy runs an elec. on my Volvo, and its nice. But its an era thing.
- This migth be a good ideer, go for it.

Regarrding second row of question:
- Yes, it should be doable, but there are nothing wrong with the Stock cam kits from a Blue Flame corvette, ot Canadian Pontiac 261.
-I dont think there is, but its possible to adapt one from a carb manifold, but again I would rather go for a twin carb set up then for FI. The Chevy 250 came with FI and should be possible to rob the full injection, and just adapt it to your 235, and run your Carb intake with a Butterfly setup from the pic'n'pull.
-Check the two threads I read about earlier, tons of info on internal upgrades.
- The is an engine called Chevy 261, that is very sougth after, and for good reason! They came in Chevy trucks (big Bolts), and in some canadiab Pontiacs.
But with that in mind, if you god a pressurized 235, you are good to go!

 

I a running a 261 (My avatar) in my 53 150

I have put 30,000 to 40,000 miles in 7 years running the following.

.060 over bore

Solid lifter Isky C-4 cam

Vintage Edelbrock 2 x 1

Dual exhaust

Dual points

I still have the road draft tube very little mess.

The engine starts just fine the car is 12 volt.

Running a generator charges about 12.5 to 13 volts

Bias-ply tires

I driven the car from upstate N.Y. to New England, and to Englishtown N.J. with no trouble.

Here in N.Y. we can buy 91 octane non ethanol at most stations.

I don't know if there any roller cams currently on the market. McGurk did make a roller cam for the BlueFlame back in the fifties

Don't forget these cars were driven everyday in the fifties.

 

I had a 235 and a 261 in my truck in the past (currently a 348). The 261 was mildly upgraded. My experience with these engines is that they are most reliable as is. They seemed to start and run no matter what. I think they are great engines as is, and even better with some upgrades. But they can get expensive when upgrading/rebuilding, so a V8 may be yield better ROI. Yet the six does has a certain cult quality about it. Regardless they run and sound great (dual exhaust and carbs), good luck.
don

 

Just curious, is a single two barrel or two single barrels?

 

2x1 means two times one barrel carb. That's a pair of one barrel carbs. 1x2 would be a single two barrel carb.

On the list of modifications....adding EFI adds a whole new realm of stuff that could be installed poorly and cause problems, or fail and cause problems. Carbs take some work to maintain, but the original fuel system has the built in advantage of being simple.

Why add an electric fan? just more stuff to go wrong! These things don't tend to overheat if everything is in good condition. If the existing radiator is still working well, then you should keep it. It has the advantage of being repairable. It has already been recored with a modern tube and fin core, as evident in your photo. Also, it is the 1954 radiator, so it matches the engine.

PCV is a good idea, if you can find the original equipment installed on a 1962 engine then it will be like an OEM setup.

Valve seats...we don't know what's in your engine now. Maybe someone already installed seats? It might be a good idea to add them if you plan to have the engine apart at some time. Also it might be a good idea to replace the timing gear on the camshaft, if it's still the original Bakelite type. That is one part that can fail, and cause problems.

My overall sentiment is that the best thing you can do to make sure your car is reliable, is to get to know it, and understand how it all works. Spend time reading the original GM service manual.

http://chevy.oldcarmanualproject.com/shop/1949_53/index.htm

Learn how everything is supposed to work, and get some spare parts, and practice working on different parts of the car.

Old cars were designed and built with the idea of periodic maintenance. If you accept this concept, then you can have a reliable old car, without having to resort to modern technology.

 

Thanks for your feedback guys.

EFI is the biggest "maybe" on my list and I don't intend to do it if I can't drop on a single-barrel kit that doesn't look too out of place.

Thanks for the info on the timing gear! As far as a fan, I was considering one I could operate with a simple toggle switch in case I end up in city traffic. I haven't had the chance to drive the car on the road any significant distance to find out it's current cooling capability, but if I was to have issues, then this was a mod I was considering.

I know the engine still has the standard heads. Grandpa was still running lead additive in the gasoline and recommended putting a bit of diesel in the gas if the valves try to stick (I'd like to avoid this). The engine was rebuilt at some point in the 60s after a bearing seized, but I don't know what all was done with the rebuild.



On another note, where could I get an air filter for this carb? We've got an oil bath filter somewhere but I'd like to run a paper element filter on it for now, rather than nothing at all.

 

Some times i see somebody write in about a 50 or 60 year old motor. They are still running it on the street, and want to make it :"Reliable". If it's still running after 50-60 years, I would say they got it right the first time. Still, If you look at the web site for and maybe join Inliners Internaaaational. I have seen several threads about EFI on an older Chevy six. People who have done it seem to like it.

 

Hi. My 46 Chevy Coupe has a 1957 235 inline in it & is a great Hwy driver with a few modifications. Engine is shown here in my avatar. The engine is bored 0.060 with flat top pistons, hardened valve seats, 264 grind Clifford cam with solid lifters, Langdon conversion distributor with HEI,, 12 volt & alternator, & everything inside the engine new parts except the reground crank. Has the Clifford dual 2 carb intake with 2 two barrel Weber Carburators & progressive linkage, Used a Lokar accelerator cable with a modified bell crank so I could keep my original starter with floor push button starting, dual shorty tube Clifford headers & dual exhaust with stock mufflers. The Clifford intake manifold has bases for 2 4 barrel carbs & furnishes aluminum adaptor plates for what ever carbs you use. So you could use either single barrel, 2 barrel or 4 barrels. This intake manifold is hot water heated to actuate the chokes & it works great.
With the solid lifters I run the Valvoline 30 weight oil with the zink in it. Think they call it ZRI ? oil.

I had to use original flywheel to use original starter to make gear teeth match, resurfaced flywheel and a new stronger clutch. Running original 3 on the tree & original torque tube rear end but changed out the 411 ring & pinion with a 355 to have a better Hwy rear end. It is a daily driver now & with this set up it cruises at 65 MPH at around 2500 RPM . I installed Coker radials in 600R16 front and 700R16 rear.
It is not a racer with my gear ration & original 3 speed but is a great driver.
It was repainted & new upholstery by previous owner in 1990 and still looks great. In the future is a new wire loon, vintage air conditioner & new rubber around all the glass.

 

The GM TBI came V6's between 173-262, and a bunch of V8's. There are a few different sizes of throttle body bores, and injector delivery rates. They have a readily adaptable pattern on the bottom. There are plates to put them just about anywhere (not 1bbl). There are manifolds for the 235 that cam make this happen.

Put a good-sized air cleaner over it, and you won't see it.

I have a GM TBI on the 200 for my Falcon. It came from here: http://www.affordable-fuel-injection.com/

You can roll your own, if you have more free time than me. It is mostly yard parts.

Just be aware, if we keep talking about EFI on the main board, this thread will get reported and deleted.

 

As for the PCV valve, that's easy. Pull the road draft tube and measure the hole. Go get a freeze plug for that size hole. Get a straight through PCV valve and grommet from the parts store. Drill a corresponding hole in the freeze plug for the grommet. Shove it all in, and run a hose to the manifold.

 

235/261's use the same 1.5" exhaust valves as a small block Chevrolet.

I have 1.5" Manley Stainless in my engine
Part # 25165

261's use an alum cam gear
Melling # 10577-8

With very little machine work A.R.P. 460 rod bolts can be used
A.R.P. number 155-6003

I would advise this when resizing the rods

 

Truck 235s also used the aluminum gear.

 

The weak link was the stock transmission/rear.

The two "modern" upgrades I have made are a late fifties Corvette 3 speed and a 1957 Chevrolet rear.

 

i love my bolt, ive done a couple things to ''improve'' it. i changed out the points for a petronix set up along with their coil. also did cap,rotor and wires and went up to r45s ac plugs gap at about 42thou and set timing 4 degrees advanced. split exhaust manifold dual exh with glass packs ran all the way out. finaly after going through 3 carbs i have one that runs great. i cut the oil bath part of the air cleaner off and am running a fram 326 air filter, i believe the oil bath set up is just fine for a stock engine but i was farting around one day and converted it to a paper element . i also pulled the draft tube and put a pcv set up in the old girl and its been working fine.
just do the basic stuff and you will be fine
good clean fuel system
good clean cooling system
proper tune
remember its a 235 and not an ls1

 

Yup. I would head a different route for a "modern" vehicle.

A 10-bolt rear, and a T5. If an automatic is desired, a 700R4.

 

Why do you think a alum. radiator will cool better than a copper one. and why not just put a better fan on it

 

Thanks for the tips! I've been following your 261 build for a while now and I'm enjoying it.

Hi there! I was looking at the aluminum radiator because several different sources have told me that they cool better than the original copper radiators because of larger tubes and better airflow. I was wondering if any HAMBers had tried aluminum over copper themselves.

 

Hi again. I am still running the original copper radiator in my 46 & my engine does not get hot at all. My thoughts is you only change the radiator if it is giving problems cooling due to its size. Everything else can be fixed.

You hear from the parts suppliers all the time about how YOU need a new aluminum radiator so your vehicle performs better BUT if you think about it they sell parts, they do not fix radiators. If you fix it the parts supplied does not make money. Easy to see why they recommend new aluminum radiators. I don't need or want one & I retired from ALCOA.
That's my thoughts anyway. Jimmie

 

I am running a stock replacement copper radiator, and a 180 deg. thermostat and a mech fan.

Idling the engine just reaches the 180 mark, driving the temp drops 170

I am going to a 195 deg. thermostat

 

http://www.stovebolt.com/ubbthreads..._Top_38_Improvements_For_A_d.html#Post1004697

I am over 100k miles on a '56 235, 848 head engine rebuilt over twenty years ago, daily driver ONLY vehicle.

 

driving my .040 over 235 with no problems.
Has a original copper radiator with fixed a pin hole leak from ~5-6 years a go with JB weld, still GTG

 

You already have the best version for reliability and long life, the one with aluminum pistons full pressure oiling and insert bearings.

Start by doing a compression test and check oil pressure. Possibly do a leakdown test. What condition is it in now? How many miles on it?

If it is worn, think about a rebuild to basically stock specs. If it is in decent shape leave it alone.

PCV valve not a bad idea. Your motor was made up to 1962 which is about when they came in, maybe there is a stock setup you can get? In any case, not a very difficult or expensive thing to do.

Hardened valve seats should not be necessary. Maybe if you are doing a rebuild you could add this refinement. To preserve the valves, rings etc you can add a little Bardahl, Redex, or Marvel Mystery Oil to the gas.

FI I won't comment on. There is nothing wrong with a good carburetor. Your choice.

Electric fan and aluminum rad should not be necessary if the cooling system is in top shape. If you need a new rad, the aluminum ones they make these days are great, and probably a better buy than a recored stocker. I see you are in Texas, an electric fan might give peace of mind on hot days. But it will only work in traffic. Once you get rolling over 30 the rad gets plenty of air.

One enhancement you could make if you do replace the rad, is higher pressure rad cap for better cooling and less coolant loss. BUT if you do this, make sure you replace the heater core with a high pressure version. The original was only rated for 4 pounds.

I suppose it would be theoretically possible to make a roller cam but why? The original valve train was not heavily loaded and you would gain nothing.

One important thing you can do is maintain it by the book including regular oil and filter changes. Don't let anyone kid you that the stock bypass filter is not effective. It is as effective as any filter, just in a different way.

If you baby it, change the oil regularly, keep good oil and air filters on it etc the life of that engine is well over 100,000 miles. I don't know how far you are into that distance now.

Rebuilt with modern valves seats, low tension rings, modern main seals, synthetic oil etc you could easily double that.

Ultimate version of that engine would be the 261 truck engine, basically the same engine with improvements.

Newer 230 250 292 six cylinder engines will bolt up to your trans with the right combination of parts. You have to be careful not to overmatch your transmission and rear axle, they are the weak link when you get into the higher HP engines.

The ol' Chevy six was know as one of the most reliable engines you could get. The engine you have would be a good candidate for a rebuild. If you happen on a good 261 that would be the icing on the cake. Either would be good for at least 100,000 miles of reliable service if put together right.

I would suggest you do a compression test and if the engine is in decent shape leave well enough alone for now. Go over the brakes, suspension, tires, shocks, alignment etc and do all maintenance by the book. Make the whole car safe, comfortable and reliable before you worry about the motor.

 

I have a 261 with 2x2, mild cam, fenton headers and t-5. I used small block exhaust valves, 1952 powerglide intake valves 848 heads with a mild port, 2.8 electronic ignition and pvc valve in modified draft tube. 0.60 forged flat top pistons. I have over 40, 000 miles in my 37 PU. I love it. This replaced the 235 I wore out.

 

one of the magazines put a throttle body from a chrysler k car on a ford six. it might work on a 235.

 

I would not. Those have zero aftermarket support, and have been off the market for a long time.

 

As an added comment, my single best investment was a HEI from Tom Langdon. It really smoothed everything out.
don

 

THIS, I'm over 100k miles and the above information is what I've followed. People get caught up in what they think they need and only make things more complicated and oftentimes less reliable, just MHO.

 

they are reliable. I had one in 58 truck(now has a 261). It was a stocker with dual exhaust, triple carb setup and a pertronix electronic ignition with coil, backed by a t-5. Couldn't complain about it at all except that it was quite tired. Now run a 261 which has the aluminum timing gears(261 only) and some other mods.

 

Slow down. Get to know your way around the car as it sits first. Hang around here and read, read, read.

Don't fall into the "I just bought my first old car, plan on chopping it, bagging it, MII, small block, T5, tilt column, electric fuel pump, fuel injection, etc" trap.

I know you want to make it more reliable but know what you are doing before you open up a magazine and start ordering so called "upgrades"