The Stovebolt Site Forums The Shop Area Engine Shop V8 calling my name?

I am considering (don't panic, I haven't decided yet...) changing my inline 6 to a chevy 350. Here is my reasoning. My 58 apached supposedly has rod knock. I don't know for sure, I'm going to get her started this saturday and find out for sure. I can't afford to have my inline 6 rebuilt ($3000). Which leaves me to buy a Chevy 350 for a couple hundred bucks and a 45.00 crossmember.

IF I actually do put a 350 in, can I keep my original sm420? And if I can, can I use my current bellhousing, or would I have to upgrade to a chevy v8 bell housing? And if I upgraded to a chevy v8 bell housing, would it go in no problem, or would fabrication be needed for the clutch linkage? (a lot of questions...)

I realize this is a stovebolt site, but maybe I'll give my bolt up for adoption if I decide on a 350. I don't want too, but money may dictate my decision.

Advice needed!

Oh, I forgot to ask.

If I do have rod knock, couldn't I pull off the engine pan, move the crank, pull out the old rod, and put a new one in? I did it on a small block once, what about a stovebolt?

I would like to keep my inline if possible!

How many miles on the engine?

Replacing one rod, leaves you with 5 rod bearing waiting to bite. 8^)

You will need another bellhousing if that's still a 235. I think any truck bell housing up to 66 should work.

Look around there are a lot of inlines out there. A 292, low miles rebuild with an Offy 4bbl manifold and valve cover, sold on that auction site last week for $750.

LG

Its a 235. I'm pretty sure it has around 75,000 miles on the engine.

Thanks for the advice on the bellhousing. So to get this straight, it would have to be a GM V8 bellhousing made before 1966, to install a chevy 350, correct?

In the meanwhile, I'll keep my eyes open for inline sixes.

Yes, no reason why you can't bolt up a 350 to the SM420. I've done it with mine and it works beautifully. But that puts the 350's valve covers and distributor too close to the firewall and you have to do some clearancing work. A lot of people go with automatics so that you can reposition the 350 further forward. But I personally prefer the SM420 because it is a kick to shift that 350 manually. And the power is wonderful.

But installing a 350 creates all sorts of other problems. The most obvious is you need a different steering system because there is NOT clearance with a 350.
The next problem is your firewall, which I've mentioned.
The next problem are the brakes. The lever arm on the engine side of the firewall won't clear a V8's exhaust unless you do some significant grinding right down to the bolt that links it to the pedal.
The next problem is cooling because the stock radiator won't be adequate. And a larger stock-style radiator that can handle a 350 costs around $700 bucks. But you can install a truck radiator right behind the grill with modifications.
The next problem is that the brakes are nowhere near good enough to stop an engine like the 350, only because it accelerates so much faster than it can possibly haul it down.

Given all the problems, had I had it to do over again, I would have redoubled my efforts to locate a 292!
But I've worked through the problems and the 350 is a nice match for this truck.

You can use a truck V-8 bellhousing from a 55-59 and 63-66.
Also a 63-66 6 cyl bellhousing. 60-62 trucks use a hyd clutch and have a different release arm configuration. You can also use a bellhousing from a 67-72 truck. It has a larger center hole but will work with the earlier trans. If you change to the later 6 cyl engines (230/250/292 -63 up) you will also need the aforementioned bellhousing. Nothing from the 235 will interchange with the V-8 or the later 6 cyl. You will also need front mounts for the conversion.
Fred

Hey Guys,

RRF has a 58. They came stock with a V8 so there are no clearance issues or steering issues or brake pedal issues. Those are V8 AD issues.

If the 350 is drilled at the front for the front truck mounts it can be mounted as a stock 283 would have been. If is is not drilled for the front mounts I think most if not all of the blocks had the casting bosses where the holes go, so it would be possible to drill the holes and use the early mounts.

Easy swap. Just buy a repo firewall throttle linkage for a V8 truck and you are off and running. I used to fab them, but there are repop now. The holes should already be in the firewall for the linkage mounting.

what Lonnie said - piecea cake to drop any small block in a 58, and if you look a bit you'll likely find one that comes with the standard trans bellhousing attached

Bill

Ive done 2 of them & it's easy & rewarding. There is a kit available for the front engine mounts & the holes are already in the frame. You can use the ram horn manifolds that point straight down & have dual exhaust built at a muffler shop. The v-8 bell houseing fits the rear mounts. If you use a large harmonic balancer you have to trim a little of the front brackets. The large HEI dist winds up real close to the fire wall. I use the old point type dist with a conversion kit.

Wrenchbender,

Do you know who offers this kit and what it looks like? I found this but I wasn't sure....

http://www.speedwaymotors.com/1955-1994-Small-Block-Chevy-Engine-Mount,6725.html

Stephen - all the regular vendors have the repro factory front V8 mounts for 55-59, like this, left in the pic bolts to existing holes in the front cross member, other brackets fit existing holes in the front of the block, on earlier blocks anyway, later you might hafta drill/tap a couple yourself

the one you link there is the 'universal aftermarket' mount, the original style don't clutter under the oil pan, work a treat on mine, just like the general made'em

Bill

Wow, all of you have had great responses! In reply to Red58, I found the 55-59 V8 motor mounts. AT @ $110.00!!!!!!!! Are you kidding me?? How can they sell a motor mount kit for $110?? Does anyone know of a cheaper set?

check all the vendors, prices will vary, but yeah, they're about a hundred, maybe you wanna make up a set yourself? ..... you could get the universal crossmember for 50 instead .... + the actual mount pads for 20/30/40 .... + the required bolts for all that ...... then spend the time or $$ to drill the frame and bolt the cross member in [make sure ya get it in the right place ] .... and cuss it every time you want to change the oil or do other work under there - or spend the hundred, tighten up the bolts and get drivin

Bill

Fink- When I did the conversion on a 57 about 5 years agoI bought the mounts as shown from one of the vendors. I think it was about $80 at the time.

I'm pretty sure the only difference is in the actual block mount on the top. If I'd known that before I ordered mine I would have had a friend fabricate a set for a 6 pack. If you can weld 1/4" plate and drill 3 holes you can make a set using your existing 6 cyl mounts.

Devin

Red 58, good point. By the time a crossmember is installed, it would probably end up costing around 80-100 bucks anyway.

55 Tractor, is the main bolt/middle piece of the 6 cyl. engine mount the same size as the v8 mount? I'm sure I could have a buddy fabricate something for me. Great advice!

no, the 6 cyl mount is different is all respects - see the last 2 pics here, note the 6 has little space in the middle - in addition the top brackets look much the same, but are at a different angle and the bolt holes are in the wrong place .... you'd also have to fabricate the bottom bracket that bolts to the frame .... not to mention that buying the kit you get brand new rubber and the correct big washers to fit the donuts, which are available nowhere else ... the kits really are a reasonable deal all things considered

Bill

Gotcha, thats what I will do then. That sounds like a better option.

I replied to your private message. George

The mounts may be different but I am fairly sure you can do the V-8 swap by re-drilling either the 6 or V-8 mounts that attach to the engine. I did this to my 59 1/2 ton in 1976 while on a summer job away from home. My tired old 6 left smoke that looked like a fog bank every time I hit the throttle after decelerating. The only engine I could find was a 327 from a wrecking yard. My brain was a little "fogged" too back then so I can't remember the details but I know I did it and without any purchased parts beyond what I got at the wrecking yard.

Chuck

Well, it's confirmed. We got the motor running (it had been sitting in a field for about 10 years with the air cleaner off, and it still runs! LOL. Talk about a great motor) and found out quickly it has bad rod knock.

Unless anyone has a brilliant or cheap way to overcome this, I will be putting in a chevy 350. I think this will be the cheapest method---

Your ideas on this are appreciated---