Technical Big Block Chevy into stock '55-59 Chevy Truck

I have searched for info on this swap for a good bit, and can't find answers to my questions. Will the valve covers hit the firewall? Will stock exhaust manifolds work, especially on the steering box side? I will be using a V8 bellhousing, mounted to the crossmember. Here's pic if that will help jog some memories.

 

Stock valve covers will almost hit the firewall. The manifold on the drivers side requires grinding to clear the steering box, if you use the correct manifold.

 

another view

 

Thanks. That is the motor mount setup I will be using also. I forgot to ask, any distibutor issues, as in will an HEI fit? Also, is that a pickup manifold on the left side?

 

In addition to Jim's tips, here is what I can remember from my swap. I did my swap in 1970, so please forgive my faded memory.
I used the stock mounts, and found that I had to pound the left hand side of the firewall to clear the left cylinder head.
I centered the engine, because I didn't think to move the engine to the right for more clearance.
The manifolds I had to play with, were the manuals from a 67 Chevelle, and there was no way the LH manifold was going to fit. There was plenty of room on the right side.
I solved this problem by getting headers, I am sorry I can't remember the brand. I had to cut the back 2 tubes and re-arrange the two tubes so they were tighter to the engine and cleared the steering box.
My original installation was an M21 Muncie, and I used the stock clutch setup. I can't remember whether the shaft would fit, because I installed a Hone-O-Drive overdrive behind the transmission, which required adding a separate mount and cutting the shaft.
I used a Hurst Competition Plus shifter, and because it mounted further back than the 3 speed, the handle required some major reworking. Rather than screw up the beautiful, new handle, I made one from 5/16 flat steel and had it chromed. You can purchase a specially adapted Hurst stick on Epay, so athough it won't be cheap, it will save a fair amount of work.
I was also able to use the stock 55 throttle setup for the Holley carb.
That will be a fun project when you have it running.

Bob

PS, the only room I have in the engine bay because of the firewall clearance problem on the left side, is the stock manifold cover.

 

I think it's a pickup manifold, but it could be something else. I looked at some manifold pictures, and I'm not sure which one it was. I had it in my barn, along with several others that I had collected over the decades. I've done the swap this way twice...

I think an HEI will fit, but the one in the picture used points, and it worked fine. Never had any trouble with the points. The older I get, the more I like things simple.

 

headers...the first swap I did, I put headers on it while it still had the manual trans. I used the Hedman headers for 68-79 (at the time, 1979 was a brand new truck) pickups with the big block engine. took a little bit of tube dinging at the steering box to make them fit, but nothing drastic.

I don't know why you'd have to bash the firewall to clear the head? I guess they don't all end up in the same place.

 

I am still using the original distributor and a CD ignition box, Delta Mark 10.
Bob

 

Thanks for the replies, all good news.

 

I have a camaro clip and used factor mounts. I hade to massage the fire wall 2" to clear the valve cover


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Cool. This one is going to be pretty dull, all stock truck except for the engine.

 

when I did my other 57, I used a camaro clip with stock mounts, but I lucked out and it cleared the firewall, just barely.

 

If you don't mind the exhaust coming out the front try a passenger side manifold on the driver side . It helps clear things.

 

This would be with the wheelbase extended 2 or so inches?

 

I will look at this option. I have a set from a '72, and a 1976.

 

I set some parts in place today, and so far everything fits with the crankshaft centerline 4" from the crossmember, measured as shown. The valve cover can be removed and reinstalled, and an HEI has plenty of clearance, so points will be no problem. More and better pics in a day or so.

 

to check the "level" of the engine, I set the frame on jack stands, and make sure it's level, shim the stands as needed. Put the intake on the engine. Then place the level on the carb flange on the intake, and it should be level, also. If not, raise or lower the front of the engine as needed.

 

Thanks squirrel, I will be checking that.

 

I set the left head and intake manifold on it today, and have clearance to remove and reinstall the valve cover and HEI.

 

Next, the exhaust manifold. There was a round boss on it that I ground off, then ground it in a few places until it went in place. I bolted it up, and found the outer rear boss on the exhaust flange was just contacting the preload adjustment screw on the box. Still thinking about what to do there.

 

grind a little more....

 

And after a little more grinding, it no longer hits, in that particular spot. That boss had issues with the threads, and I may have to tap it to 7/16". I still have the manifold just touching the box, right at the edge of the donut area. I'm still thinking on the fix for this.

 

put new bellhousing mount pads in the truck?

 

You are reading my mind on that. The wife is preparing to go visit some relatives, so I will wait until this weekend to do much more. I am thinking I may be able to lower the fear of the motor

 

Phone posting... what a pain. Lower the rear of it by using something different for the mount pads. I can't find my angle finder either so I need to score a new one of those.

 

If you set the frame level using a normal carpenter's level, then you can use the level to also get the carb flange level, and that's where it wants to be.

 

You can actually ad a clinometer app onto your phone, looks like this

 

I had completely forgotten that, might give it a try. I wouldn't be so picky about it, but the truck has three driveshafts, and 4.56 gears.

 

I got back on this today, and loosened the bellhousing mount bolts up a good bit. Raised the back of the motor up 1/2 inch, and sure enough, got the clearance shown in the first pic. The right side has plenty of clearance, and I can still R&I everything.

 

@squirrel, you were spot-on here. I need to get some new mounts, and a quick check shows two or three that are for the truck, each with different part numbers. Is there any difference in these?