The 5.7 in my vert is getting tired at over 100k and it's time to refresh things over the winter.
I currently have new Trickflow heads and was wondering what's the largest displacement shortblock with forged internals that's readily available from a reputable builder.
I'm thinking something along the lines of 7.0 liters 427 cubic inches 9 to 1 compression with a Procharger pushing 15 psi and methanol injection.
The Powerdyne has been fun for the last 20,000 miles but as we all know we just want more.
This will stay as a street only fun car.
I'm thinking $15k for shortblock and Procharger including the re and re labor for which I have a master mechanic friend who races on weekends and loves doing this kind of stuff.
Anyone have any suggestions about a reputable builder for the shortblock?
Thanks in advance.

 

I don't think you will find an off-the-shelf LT1 short block any larger than 396ci. There used to be a couple sources for 409's, but they dried up, probably due to the expense of building them and the limited demand. There is a member here who sleeved an LT1 block and got it up to 427ci. Another member (now long gone) built a pair of 421ci LT1's. Given the huge expense, there's not much value in going over 396, other than the novelty of saying you did it.

You can do 1,200 flywheel HP with a 383 and enough boost.... if that's not enough, theres someone here claiming 1,200 rwHP on a turbo'd 383 or 396.

 

i have been told that even just clearencing for a 396 gets you pretty close to the water jackets, is there any truth to that

 

WIth boost,why build any bigger than a 355? You are force feeding it anyway. Whats the point? 383 is max I would go with boost.

David

 

If you REALLY want to go that big and willing to convert from LT to LS, they have 427's readily available... I honestly don't know if it would be worth it or not, I don't know what all goes into swaps like that.

 

I had a perfectly good LT1 block that I had put 4 bolt mains on.

I decided I wanted a few extra cubes and had it bored .060" over...cracked the block in a few places...the wrong places and ruined the block.

This was after the machine told me they had done this before...yeah right.

Luckily, after it happened I asked if they had any spare LT1 blocks and they did have a completely done LT4 block with Milodon mains on it and I got it for a steal.

 

Sometimes even the clearance needed for a 383 gets into water. If you plan to run really high boost, consider just 10 over on the bore.

Rich

 

That should be a baseline figure.

 

Lot's more to make 1200FWHP more like $30,000 to start.

 

Well I'm looking for more like 700hp and not 1200 so after reviewing the comments I think a 383 stroker with a Procharger at 10-12 psi would be more in line with the 15k I want to spend.
Can you guys recommend somewhere I could buy a finished shortblock then send my old engine as a core to?
I'm in Buffalo.

 

Check our supporting vendors, click the link at the top of any page. Golen and Victory would be two examples.

https://www.camaroz28.com/links/browselinks.php?c=2

 

Matt Shaff of Proformance in Rochester deals largely with race engines. But he does do some street stuff and is honest and fair at a reasonable price. Give him a call. If you do, let him know that "Doc" sent you and ask him if he has welded up that head for me yet

I like dealing with locals as much as possible.

Proformance Specialties
1115 Main St E
Rochester
(585) 288-1499