VCCA Home Forums TECHNICAL - 1945 AND NEWER 1946-1948 Replacement engine for 48 Aero.

It seems I will need to replace my engine (block cracked) Is a 1962 the newest 235 I may install? Or may I go to a newer engine? If someone knows all the options I have, it would be greatly appreciated.

The 1962 is the "newest" as it is the last year a 235 was made....no "improvements" made in the 235 after 1959 so any 1959-62 235 (or 261) will do fine.

The 1963 replacement for a 235 was a 230 engine (250 in 1966) and was longer than a 235 and different looking.No a "drop in".

Hey Chev Nut

How about the hydraulic valve issue in 235's. Are they better or more powerful?

The later 1959-62 235's are drilled for oiling and can be used with hydralic or the correct solid lifters.The stock hydralic or solid lifter cam Chevrolet used from 1959 and up was an economy cam designed for good low speed torque and gas milage...will give best power under 34 to 36 hundred RPM.This is for either cam.
A higher lift cam sould be used -the 56-58 solid or hydralic as an example but it will have less power in the "normal" driving range but more above 3500 RPM as well as a higher top speed.Just depends as to what you want.The correct valve springs must also be used.There are aftermarket cams sold for better high speed performane but the low end will suffer.

Thanks, Chevgene.

Low end torque is the name of the game with the six cylinder chev engines isn't it?

Once I get Sweetie Pie rolling and into 3rd gear, I never have to shift again. Well, almost never. :)

Valve lifters have nothing to do with power but solid lifters are used with higher lift racing type cams.This was due to the fact (back then) that they were lighter allowing higher RPM' and could be used with stronger valve springs.On todays engines this is no longer true due to high tech.

Today people install dual carbs. and high lift cams on 216/235's and never rev them up to the point where the extra power kicks in.Plus it will decrease the power in the speed ranges where they usually drive.

Gene, are you talking about RPM above..say, 6000?
I've read where some guys have these running at 6000 to 9000 RPM. Thats really twisting it.
Walt

Dual exhaust, Dual one barrels with the right main jets and manual choke will get as good gas mileage at 55 to 75 as the original one carb, Maybe better. I don't think anything but a mild "racing" cam is needed for a cruiser or touring car. As to RPMs You had better have one well balanced engine , and fabulous car to cruise above 4000 RPMs, in high gear Do you have any idea how fast a 54 Chevy car with a 3.55 rear end will run at 4000 RPM? ...that's TOO FAST!

93 mph??

The "high" RPM range for a 235 would be from 3500 to 4500 RPM.Would't plan on running it over that speed for any length of time.4500 RPM with a 3.55 rear would be about 100 MPH.Thats about twice as fast as most people drive them.

Walt,

6000 is really twisting it is RIGHT!!! To say nothing of 9000. I can't imagine 'you' could even get it to 6000 on the way to 9000.

Where were you 'reading' about that????

Bill.

I've been reading a copy of a book by a fellow named Leo Santucci. Some pretty wild stuff in this book. (Not that I'm going to do any of it) This guy makes an inline head out of two v-8 heads,compression ratios of 14:1,pretty interesting read. He claims 1000 hp is capable out of a six, with about a million dollars worth of modifications. Me..I'll be content with a burst of 70MPH to pass when I need it. I'll be sticking to a stock 235.Or a 216 if I can find one locally, an ideally with a casting to match my 48.

I gotta admit tho, I was wondering what it would be like with a modified engine, used in conjunction with the tip toe matic overdrive. Wonder what the high end would be? The overdrive provides a 2:96 ratio. The trick would be getting it all to stay together.

I believe Santucci's book is mostly about the 1963 and up engines which have the same bore spacing as the SBC, seven main bearings and the same type rockers as the SBC. Some of the old sprint car guys talked about 7000 RPM with modified four bearing engines though.

Many of the early overdrive cars had the same or a higher top end in third than in third over. The shift point from third to third over would drop the RPM out of the power band required to move the car through the air at high speeds. The overdrive was just used to lower the RPM for driver comfort and to improve engine life. I had a **** that could do eighty in second and 79 in high, so lower numerical gearing doesn't always improve top end.

From road test of 1955 power pac V8 with overdrive-1955 Road & Track.

Top speed in O.D ( 4.11 ratio-2.87 in OD)-102 MPH at 3680 RPM.

Top speed in 3rd gear (4.11) 104.7 MPH at 5360 RPM.

Engine was below max. power curve in OD and did not have enough power to attain higher speed.They were of the opinion that the stock 3.70 would have given a higher top speed.

Motor Trend road test of 1955 6 cyl with OD gave it a top speed of 95 MPH....

My guess a stock 216 with OD and 4.11 would top out at an actual 85 MPH as it just dosent have the HP to push the car thru the wind faster than that.

The factory listed the top speed of a 216 with 4.11 at about 81 MPH (two way average)...which is a little over 4000 RPM...and the power drops off rapidly after that.

One of the mechanics in the dealership I worked at in the "old days" had a 1947 that he installed OD in.He said it would do 95 MPH on the speedo. but that could have been down hill with the wind.The average stock 1947 (if it was running good) would do about 85 on the speedo.

He also said it got 24 MPH on the highway.Many owners back the claimed 20 MPH as the average roads didn't permit driving much over 60 MPH.