Can the Chevy 250 Straight 6 fit in the Advance Design

[pvienneau]

All, I see some available Chevy 250 straight 6's from the 70's available at great prices. Looks like people are upgrading to 8's. Any experience out there using these for an Advance design 3100 build?

Thanks

Patrick

[OrrieG]

Take a look at these threads over on the stovebolt site.

http://www.google.com/cse?cx=partner...wap&gsc.page=1

[dwcsr]

Originally Posted by pvienneau

All, I see some available Chevy 250 straight 6's from the 70's available at great prices. Looks like people are upgrading to 8's. Any experience out there using these for an Advance design 3100 build?

Thanks

Patrick

Yes, its a good swap I just did a 292 which is the same dimensions just a taller block. We used the stock pedals and an SM 420. We did modify the radiator position to get an electric fan in there but its an easy mod. You bolt the radiator to the front side of the support and trim out the upper and lower valances, The hood closes fine in that position. You'll need a drive shaft made. The rear mount has to be made to look like a 55-59 so you can use the bell off a V8 if your using a SM 420.

The nice thing is they make brackets for PS , ALT , AC for 230, 250 , 292.

[NEWFISHER]

I have run 2 and its a tight fit but does work well. You have to position the rear valve cover a finger width from the firewall so you can clear the radiator with the mechanical fan. 5 degrees is all you want or the lower blade could hit the rad support under hard accel and stretching a rubber mount.

[mr48chev]

As Dave and Newfisher said it's a tight fit but after you get it done the effort is worth it as you end up with a nice running six cylinder truck that gets good gas mileage while being able to run at highway speeds if you have it geared out right.

I put probably 100K on mine in 15 years with the 250 in it before I wore it out to the point the engine didn't want to run. That is on a 74 engine that had 95 K on it when I put it in in 1989 as a temporary engine until I had my 396 ready to go.

I shortened the water pump shaft and swapped pulleys to get clearance between the fan and radiator but that called for a thin blade flex fan that doesn't pull enough air at idle speeds. This time around I am going to have to figure out how to run a fan that pulls more air.

[pvienneau]

So the 250 requires some possible firewall and other mods. Is this the same for the newer 235 truck engines?

[Dan in Pasadena]

Originally Posted by pvienneau

So the 250 requires some possible firewall and other mods. Is this the same for the newer 235 truck engines?

I think what was related WASN'T "firewall mods" it was bolting the radiator to the front side of the support to gain clearance.

I'm no expert; not having done this mod, but why WOULDN'T the later 235 fit as well as the original, earlier 235? 235's came stock on these trucks and the later ones were the same engine externally.

[pvienneau]

Makes perfect sense. On additional research I found Dan is correct. Now for a Transmission.

[dwcsr]

235 is dimensionaly the same and will fit with a water pump modification. The 230, 250, 292 will also fit without firewall and or radiator support changes. I moved the radiator so I could use a Taurus E fan.

The reasons you would go to a 230, 250, 292 is that it gains you durability, lower cost of rebuild and performance parts, performs better at highway speeds and more power than a 235, no more oiling system issues that plagued the 235, use of an auto trans or late model standard without plates and adapters. its a long list of why you should.

[Dan in Pasadena]

I like the idea of a later 235 over an early splash oiler one. That said, if it were mine I'd want the performance a 292 could give you. Backed by a 200R4 or 700R4 I think you'd have a very nice driving, powerful and UNIQUE truck. At least that's my POIT of view.

If my truck had come with its original straight six, I'd have kept it or gone to the 292 as well.

[iowaboynca]

If memory serves, Newfisher has a nice write up of putting a T5 5-speed behind his 235. That is if you want to keep 3 pedals and an e-brake. Read your build page and it all depends on how 'original' you want to keep it. Personally, i think modernizing an inline 6 with a modern drive train behind it is the way to go! Either way it looks like you've got some options. Good luck on your search!

[curmudgeon]

To expand on Mr. Chapman's post, the '54-55.1 235's are the "later" full pressure engines and have the H2O pump in the correct, higher position. A '55.2 - '62 235 out of a later TF truck or car will have the H2O pump positioned lower and will need the water pump modification, unless an electric fan is used.

Also, a 292 has a taller block with offset motor mounts, compared to a 250, length is similar and height is not a problem. Plus new motor mounts have to fabbed anyways.

[dragoncrx]

If anyone is looking for a 250 in the Sacramento area I will have a complete engine for sale soon out of a 75 firebird. For a couple hundred bucks I will post in the classifieds once I get it pulled I am using the subframe for my 58 chevy truck.