The Stovebolt Site Forums The Shop Area Engine Shop 59 3200 SBC Mounts

I just picked up a 59 3200 longbed stepside that I have been wanting for 20+ years and I already have a mounting question.

I have what is supposedly the original 4 speed, but no engine. I have 85% of an SBC from a previous project that I am looking at putting in it to get it going. Long term, I might look for an original 348, but for now I want to get on the road and enjoy it.

My question is about the off-the-shelf motor mount adapters. I am looking at these from Speedway because I don't want to make any permanent mods to the frame: Speedway motor mount

I have seen references in a few threads here about using inexpensive conversion mounts to simplify alignment and avoid modifying the frame/crossmember, but the original mounts do not appear to be nearly as widely spaced as these would require unless I am completely misunderstanding how they install.

Based on looking at it, it looks like these mounts require adding an extra set of holes in the frame rails and just ignoring the original mounting holes on the crossmember. Does that sound right?

Alternatively, I am wondering if my truck actually had the 6 cylinder originally and that is why it does not have the holes to use these mounts?

So I commented that I am interested in lookong for a 348.

I based that on the previous owner saying it was originally a V8 truck. Looking at the specifications pdf from GM Heritage Center, I am not actually sure which V8 it would have had. When I can get out to the shop, I need to pull the numbers off the data plate. I seem to recall seeing a link in another thread to a calculator that translated those.

In the short term, I want to get it moving under its own power so I can spend weekends doing projects on it with my son. Long term, I am considering doing a 4x4 and/or IFS swap on it, but I figure that is a couple years out. I am still buttoning up my last project but I could not turn this truck down for the price.

Hy Fibonachu, Welcome, firstly I would really appreciate it if you would proof read your post before you post it, it takes me a while to figure things out when words aren't spelled correctly. 348 engines were only available in the larger trucks from the factory and they used a horseshoe front mount and an mount on the front crossmember. If the truck left the factory with a V8 it will have the front engine mounts riveted to the front crossmember, those mounts are not installed on chassis which left the factory with a six cylinder engine. You can purchase a front mount kit from many suppliers that will give you the stock V8 front engine mounts, those coupled with the stock cast iron V8 bellhousing will give you a stable engine mount system. The stock front V8 engine mounts will have to be modified to work with engines with the large diameter harmonic balancer. The front crossmember has all the holes to mount the factory V8 engine mounts, hope that helps.

I would verify that the 348 engine you obtain has the mount holes drilled and tapped on the front of the engine to be able to use the factory 59 SB front mount configuration. 348's in cars used the side mounts which would would likely require an aftermarket cross-member type mount for use in a truck. I have done several 6 cyl to SB conversions on TF trucks and all of the front cross members were drilled
for the V-8 mounts. Perhaps the holes are filled with crud but they should be there.
Fred

those mounts from speedway are not original style, they're for side mounting an engine - the repro original type is like these - seen installed here . . . as 3B sez, the bottom brackets would be factory riveted to the frame if the truck originally had a V8

Bill

Flxible - thank you. That is the question I was trying to ask. I was not looking at the parts I thought I was.

3B - My apologies. I discovered the forum late last night and was not paying as much attention to my typing as I should have been.

I had another post in this thread with some more info, but it appears to have not been approved by the moderators. A couple newer posts from me got approved, so maybe that one got lost in the shuffle.

The previous owner said it was originally a V8 truck, but the hood ornament is missing and the mounts that Flxible linked to are not present. If it was originally a V8 truck, then those were taken off, but it seems more likely to me that it was not.

Looking at the 1959 Chevrolet Truck Specifications pdf from the GM Heritage, it looks like this truck would have had a 235 originally? If I am reading the document correctly, a 32 series thriftmaster would have had a 235 L6 and a 32 series Trademaster would have had the 283 V8. Given that I don't have the mounts, the 235 seems more likely.

Does that logic work out? Or am I missing something else here?

My short term plan is to just get AN engine in this truck to get it running and driveable. I want to convince my wife that this is a cooler truck than the last one I built and I can't do that without an engine. Long term (3-5 years out) I want to either restore it to basically original or do a full custom resto-mod on it. I want to end up with a 4WD setup when I am done, so whether or not I can find a NAPCO front end will affect that decision. In the meantime, I don't want to make any changes that force me to go one way or the other on it.


Fred: When you did those conversions, did you mount the SBC to the stock V8 mounts? Or did you do side mounts? I have read anecdotal horror stories about people using the original crossmember mounts for an SBC and twisting the whole thing off because of how long of a moment arm the SBC has on those mounts. Is that a real concern in your mind? I am not sure if 3B's comment about getting a stable mounting between the front crossmember and the bellhousing only applies to the older 348s or if that would also be true for an SBC.

I have done them both ways. I converted my 56 to a 350 engine in 2000 using the stock V-8 front mounts and the rear bellhousing mounts.
That is the factory configuration and works well. I have also used the aftermarket cross-member for center mount engines with both the bellhousing mounts or the single rear mount used for later model manual and automatic transmissions. What you don't want to do is use the "bird leg" front mounts with the rear center mount. There is too much span front to rear with that configuration. That may be the horror story you have heard about. I encountered one that the only thing that was keeping the engine and transmission in place was a solid welded exhaust system.
Fred

ALL 55-59 trucks with factory V8's have a "V" as a prefix to the chassis serial number (door post tag).

Mike B

I use the very simple, easy to install, tubular cross member motor mounts and tranny mounts. Bolt on. They attach to the standard 3 hole SBC/BBC side mount.
click
or click

I don't think you need to focus on front mounts.

Unless using side plates inside the frame using existing frame holes to hold them and attaching the after market crade to them, you then would of course ruin a part that is unobtainable, the frame.