Pontiac GTO Forum banner

1 - 3 of 3 Posts

·
Registered
Joined
·
137 Posts
Discussion Starter #1
Hi all was looking for ideas on motor combos this is what I am working with
455 or 400 block. for stoker kit the 455 would be a 30.over bore the 400 would be 60.over bore I have both blocks and crank would be new 3.00'' or 3.25'' for mains wanted to run # 62 head for now till can get more cash 30.cc dish pistons would one block be better then other I think cid is very close ..im just looking for good street car with lot of low end power its 67 GTO auto 355 gears...after 1 block is fully machined I have very little cash so only can work with what I have both blocks nothing special no # matching's the 455=1973 the 400 =1967 not GTO blocks :(
 

·
Super Moderator
Joined
·
5,751 Posts
Well, I like the stroker 400 specifically because of the smaller mains. That leaves more meat in the main webs, and therefore 400 blocks are stronger. I haven't looked recently, but there used to be 4.21" stroke cranks available in 3.00" mains. Put one of those in a +0.030 400 and you have a standard bore 455. Or, do what I did and go with a 4.25" stroke and a +0.035 overbore, and you have a 461. The other advantage of the smaller mains is they tend to oil better - the larger journals "try harder" to fling the oil out of the bearings.

To be totally honest though, if you're building a purely street cruiser that's not going to see much if any strip time, a "regular" larger journal 455 will work just fine.

On either engine, it would be worth your while to put some effort into locating a set of 6x-4 heads. Run those in either a 455 or a 461 with stock head gaskets, flat top pistons and you're at 9.2:1 if you don't zero deck the block, 9.5:1 if you do. Either engine would have good to very good quench characteristics (much better than it would with big 'ol dishes in the pistons). --and the parts should be cheaper to boot.

Bear
 

·
Former Moderator
Joined
·
2,895 Posts
Better motor option.....I have some ideas but I don't think they'll be very popular with the membership here :D.




Seriously though...:agree with Bear 100%; A stroked Pontiac is hard to beat and these days ironically are really the "good ol' days" for Pontiac lovers because of the availability of good blocks, cranks, rods and cylinder heads. 20 years ago it wouldn't be nearly as easy to put together a streetable, big inch Pontiac with aluminum RA IV heads, it just wasn't gonna happen. Now it's not cheap, but it's not crazy money either to put together a stomper Injun.
 
1 - 3 of 3 Posts
Top