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Trying to put a Pontiac GTO 400 engine in my Chevrolet truck.

23 messages,  Last post on Jan 30, 2013 at 8:26 PM

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What is this discussion about? Chevrolet C/K 10 Series, Performance Mods, Truck

Messages Page 3 of 3

#16 of 23 Re: Trying to put a Pontiac GTO 400 engine in my Chevrolet truck. [Mr_Shiftright] by num1pontiacman

Apr 14, 2011 (6:36 am)

Replying to: Mr_Shiftright (Apr 13, 2011 9:18 pm)
Yes, a 326 does have cast pistons and crank. I had one in a 67 tempest that had 338,753 miles on it when it was pulled. Ran good, didn't smoke and had good compression and a .006" lip. If maintained well those high nickel blocks wore very well.
The application dictates the parts necessary for the build in any build. Cast pistons and crank are perfectly fine in the right application.
58 GMC trucks came with a Pontiac 370 engine from the factory. I have one on an engine stand with over 700,000 verifiable miles on it. It will clean up at .020".

#17 of 23 Re: Trying to put a Pontiac GTO 400 engine in my Chevrolet truck. [num1pontiacman] by Mr_Shiftright HOST

Apr 14, 2011 (7:59 am)

Replying to: num1pontiacman (Apr 14, 2011 6:36 am)
I agree, cast crank and pistons are fine for everyday use but woe to the man who attempts to add significant power to an engine built that way. It's not going to end well.

#18 of 23 Re: Trying to put a Pontiac GTO 400 engine in my Chevrolet truck. [Mr_Shiftright] by andre1969

Apr 14, 2011 (8:03 am)

Replying to: Mr_Shiftright (Apr 14, 2011 7:59 am)
I agree, cast crank and pistons are fine for everyday use but woe to the man who attempts to add significant power to an engine built that way. It's not going to end well.
 
I think Mopar switched from forged to cast crankshafts sometime in the mid-1970's, and I've heard a lot of people groaned about it. Would that have given them a higher failure rate in everyday use as well, or just cause problems when you try to hop them up?
 
If you have an engine that uses a cast crank and pistons, could you just put swap in a forged crank and pistons? Presuming, of course, that an older version of the engine with the exact same bore and stroke used forged at one time?

#19 of 23 Re: Trying to put a Pontiac GTO 400 engine in my Chevrolet truck. [Mr_Shiftright] by omarman

Apr 14, 2011 (10:18 am)

Replying to: Mr_Shiftright (Apr 14, 2011 7:59 am)
I don't remember Pontiac cast cranks and pistons from that era being trouble prone for street/strip use. Nodular cast iron or Armasteel (PMI - not steel despite the name) was used for most Pontiac V8 crankshafts except early super duty (racing) engines. Depends on your definition of "significant power" though.
 
For example, and maybe a true Pontiac guru out there can take a better whack at this, I looked up factory GTO Ram Air engines:
The original Ram Air 400/360hp ('67?) used cast crank and pistons.
Ram Air II 400/366hp = cast crank and pistons
Ram Air III 400/366hp = cast crank and pistons
Ram Air IV 400/370hp = cast crank and forged pistons
Ram Air V *crate engine* factory HP rating? = forged crank and forged pistons
 
Super Duty engines prior to the '73-'74 455SD used forged steel cranks. But other than the Ram Air V crate engine, was there any factory GTO Ram Air engine with forged crank+pistons? I'm thinking that if you are driving a Pontiac street machine and have problems with damaged cranks or "holed" pistons, there may be other issues causing that -- detonation, excessive wear or poor assembly?
 
If the OP was considering a Pontiac 326 swap into a GM truck for the street then forged crank and pistons sound like overkill to me. Just depends on how heavy duty the truck's purpose will be.

#20 of 23 Re: Trying to put a Pontiac GTO 400 engine in my Chevrolet truck. [num1pontiacman] by tjb1ham

Jul 07, 2011 (1:10 pm)

Replying to: num1pontiacman (Apr 14, 2011 6:36 am)
I am looking to put a Pontiac 400 into my '72 GMC Pickup (already have both).
 
To:num1pontiacman
You said you have pictures and info to do a stock parts bolt-in?
Care to share?

#21 of 23 Re: Trying to put a Pontiac GTO 400 engine in my Chevrolet truck. [num1pontiacman] by tjb1ham

Jul 07, 2011 (1:13 pm)

Replying to: num1pontiacman (Apr 09, 2011 10:52 am)
I am looking to put a Pontiac 400 into my '72 GMC Pickup (already have both).
  
To:num1pontiacman
You said you have pictures and info to do a stock parts bolt-in?
Care to share?

#22 of 23 Re: Trying to put a Pontiac GTO 400 engine in my Chevrolet truck. [num1pontiacman] by ssbelair64

Jan 30, 2013 (5:46 pm)

Replying to: num1pontiacman (Apr 09, 2011 10:52 am)
Hey im working on putting a pontiac 71 400 into my 65 chevy pickup. You mentioned that you used componants for a direct bolt in. Which motor mounts did you use?

#23 of 23 Re: Trying to put a Pontiac GTO 400 engine in my Chevrolet truck. [ssbelair64] by num1pontiacman

Jan 30, 2013 (8:26 pm)

Replying to: ssbelair64 (Jan 30, 2013 5:46 pm)
It is a combination of motor mount perches, motor mounts and the motor mount bracket that bolts to the block.
All 3 are needed. I can't post photos here, fire off a message to me at chris_r29hotmail.com and I will try and point you in the right direction.

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