pontiac 1958 front cover on 1966 engine

i want to put a 1958 front cover on a 1966 engine i know that coolant flow is changerd 1959 what will happend?
i try to use stock engine mount and put a 400 trans on my gmc pickup will send picture on this.

 

You won't have the correct return holes on the block. Plus you would have to add the elbows onto the head, but I don't think it would work anyway unless someone else has actually made it work?

Here's a good read on Pontiac cooling

http://www.pontiacsafari.com/EngineCooling/index.htm

If you need the steel cover for a front mount, I have a 60 cover on my 66 389 and use the 66 gasket. It's also been opened up for the newer style seal like in this article.

http://www.pontiacsafari.com/L1Garage/FrontSealUpgrade.pdf

 

thanks good info have a 1958 100 gmc truck with hydramatick engine i stuck but got an extra 1957 engine with the truck so try to find a 1960 frontcover.i have a 1966engine ready to install and 400 trans
got car from texas 3weeks ago.
ken
sweden

 

You can't do it that way. To accomidate the front mount the blocks have a couple of extra holes drilled in the front. The last year they did that on was the 1959 389 blocks. Otherwise it would be a matter of swapping heads and pistons to match up. It will certainly physically bolt on there, but you won't be able to use the front mount.


Personally what I would do is run the 59-60 side motor mount and just add some eyes to the frame - something like a mount kit intended to put a Chevy V8 or a universal weld-in kit would probably do the job. That mount will bolt up to the later block no problem.

 

One more thing, the 1958 crank was smaller with 2.623" mains, the 1959-up 389 and 400 are 3" even, so the cover may not even fit over the crank, and even if it fits, finding a seal that will work could be an issue.

 

Find a 60 cover. It's cast iron and it has the provisions for a front mount. Also, it will work with your 66 heads. ie. water flow in the right direction.

 

The 57 engine needs the matching reverse cooling cover with the outlets to each head, not the 60 cover. That was only for the 60 and up engine with standard cooling.

 

ok i try to find a 1960 cover for the 1966engine and trans for later.
meanvile i started to get the engine turning for use of hydramatic trans from the truck. with the complete 1957 engine.
drilling top of pistons and loose it this way save block and rods it is a 336gmc so if you bore it you vill have a 370 with forgedsteel rods std bore .same as pontiac 1958 only year.
it will be a upgrade with the 347 pontiac engine as it have 4-port intake.
ken

 

got the 1960 front cover from macine shop today took some pictures and mesurement cross ram is not going in gmc found gmc valve covers from 1958.

 

I'm digging that cross ram,would love to find one for my Catalina.

Jratz

 

Congrats on a sweet truck Ken, these are so hard to find in any quality condition over here. Best wishes for a completed driving hot rod. ~sololobo~

 

There's still the matter of some holes deleted from 1960 and up blocks. 1959 is the last block you can bolt in with a front mount setup with no modifications, unless the truck mount is different from that used in passenger cars. Which it could be, it depends how late the front mount was used, the GMCs got a 336 CI Pontiac engine for a few years until the V6 came about.

 

I got my intermediate bracket from a guy with a factory v8 Pontiac GMC and is the same as the car bracket. The 55-58 intermediate bracket will bolt right up to a 60 cover.

The one think you will loose with the newer engine/trans is the rear side mounts that would have been on the early transmissions. I would not go off the front cover mount and rear trans mount, there's too much length and will damage the tailshaft I believe.

Here's what I ended up with, these were chevy rear engine mounts from speedway I adapted to a BOP pattern.

 

thanks for pic this is my plan one front .side mount gmc have crossmember where trans sit on and th 700 rear mount.i have a straight front axle to thingk about .
on the 336 org engine there is a hump on rear passenger side and 1958 cast code so this block should be same as hi preformance 1958?and bore is smaller than 370 .std 370 pistons will fit?if you bore it 4.0625?
i put pic later today.on crossmember

 

here is pic of crossmember mesured that i have to move it or fabricate it 5 inch forward to use adaptorplate metal.

 

Thats an awful lot to bore it that much. Either go .030 to clean it up or more as needed only.

If you had to use that block a closer bore piston would be the 350 but it has a differant stroke. The 350/389/400 all have a 3.75 stroke. Also the valve reliefs are differant in the 350/400 pistons.

 

i will not do anything with that engine now but for 1958 passenger car collectores this could be a block to think about nos pistons std bore are cheap and would be correct in that car.truck pistons is low compression and heavy so org pistons is no no here.

 

got trans hooked up to engine today more to do with adaptorplate and gold paint it im putting engine in truck and tighten down front engine mount.then i have to level engine and make rear mount last thing to do is middle 2 mount using the stock crossmember.

 

see if pic goes this time

 

How are you going to run a bypass hose from the cover to the intake water crossover?

The front hole that would normally mate up to the backside of the cover I tapped for 1/4 npt and had an elbow initially and put in a 3/8 npt adapter to 1/4 npt with a matching barbed elbow fitting same as on intake on the cover. I had an extra hole on the water crossover and ended up with a 1/2 bypass hose to the cover.

 

do you mean it will not work without an connection from intake to cover.i plugged it and if it no go i can make a t cuplling on tempgauge hole or a hose to rear of right head there is a hose outlet maby good to transport heat from rear of engine.
do you have a picture of our engine in your tread?

 

This is how it ended up. I had to remove the factory pipe in the cover to make room for the alternator. It should have a working bypass installed, it allows coolant circulation before the thermostat opens up.



There is another flat spot on the water crossover on the passenger side that could be opened up, but you've already put the engine together. You wouldn't want the metal from cutting getting into the cooling system.

A t coupling probably wouldn't look the best, especially after the work you've done to clean and paint your engine up nice.

The heater nipple on the rr head is designed to be used for the heater core. Not as a return for the bypass.

 

I've used a 57 front cover/water pump on my 57 block with 1973 heads. I knocked out the frost plugs from the fronts of the heads and made up a pair of adapters/spacers to utilize the external water necks. Took a little "carving" of 1/4 inch steel plate but should work ok.
Wish I could use the old 1957 water distribution tubes but I'm sure the newer heads are built completely different from the early ones...I'm gonna depend on simple heat-transfer to keep the heads cool..after all, from '60 on, Pontiac reversed the cooling AND didn't depend on cooling tubes.
BTW, it's been said the two bottom holes are missing to mount a 1960 cover to a later block....even if they are [not sure] I se no reason not to use the 1960 cover as a pattern to drill and tap those holes. The 1960 engine used side mounts BUT! But the 1960 cover is drilled and tapped for the 7/16ths center/front mount bracket used from 1937 to 1957 on cars and even later on trucks.
I would definetely use that 1960 front cover and use the old GMC center mount bracketry and mount.

 

Rocky, I didn't have any missing holes to mount the 60 cover to my 66 block? It doesn't utilize the lower 2 bolt alignment dowels like the newer covers if thats what your talking about because of the spring and cork seal behind the early style covers. There is alot more slop in the bolt holes of the cover and the alignment dowels weren't needed, but I had it bored for the newer style seal and used an alignment tool to center the cover to the crankshaft.

 

i understand now what you mean .im not sure but on waterpump cover the outlet is supposed to go to heater core i mean that you have pressure on that fitting this got me thingking now i dont care if i have a t on line i have to get heater online.if i get a t with small pipe to the inlet on heater core and let it bleed to pump cover true return of heater core and return of heatercore goes to intake crossover.i will make this so the battery tray cover the 2 t cuplings on back of engine where the battey is and one t on water crossover.i did a paper drawing this morning and seems to work on paper.

 

The one outlet on the cover goes to the water crossover on the intake. The heater nipple in the rr head goes to the heater core. The return would have been in the lower hose or like my 55 on the radiator.

 

"....from 1937 to 1957....."

Pontiac used a front mount through 1958.

 

welded first 2peces on adaptor plate and think i can use stock mid mount adding a some more metal

 

engine in truck now i did some chages with whaterpipes

 

adapterplate to th 700 ready for paint and i had a request for pic on 1957 timing mark so i put pic of my 347 in my pontiac safari