400 genII block
Thread Starter
Melting Slicks
Joined: Dec 2001
Posts: 2,437
Likes: 1
From: Gainesville Fl
400 genII block
i know you cant safely bore and stroke an lt1/4 block to over 396ci. my question is does anyone like dart or motown make a 400 smallblock that would accept lt4 intake and heads? im curious if there is a way to safely get 427+cid out of an ltx even if it isnt a stock block.
Safety Car
Joined: Dec 2006
Posts: 4,290
Likes: 6
From: St Marys GA
I believe that the 400 block uses the same intake and heads as the 350. Might be wrong on that count though.
IMHO, if youre going over 400cu, go ahead and go all out with a miniram or something like that. Also, with that much displacement youll probably want 195cc heads or something like that, depending on where you want the power.
IMHO, if youre going over 400cu, go ahead and go all out with a miniram or something like that. Also, with that much displacement youll probably want 195cc heads or something like that, depending on where you want the power.
Thread Starter
Melting Slicks
Joined: Dec 2001
Posts: 2,437
Likes: 1
From: Gainesville Fl
anyone else know about this?
im having trouble when looking at aftermarket blocks knowing if they are genII or not. like i said, i know you cant safely bore and stroke a LT motor bigger than 396 but was curious if there was an aftermarket block out there that would let you do it. if you have an LS you can either sleeve ur cylinders to get big cubes or go the C5R block route or get an LSX block. i was curious if we had any kind of options like this with a GenII block that would still accept LT components like heads and intake. does that make sense?
im having trouble when looking at aftermarket blocks knowing if they are genII or not. like i said, i know you cant safely bore and stroke a LT motor bigger than 396 but was curious if there was an aftermarket block out there that would let you do it. if you have an LS you can either sleeve ur cylinders to get big cubes or go the C5R block route or get an LSX block. i was curious if we had any kind of options like this with a GenII block that would still accept LT components like heads and intake. does that make sense?
Last edited by 1996man; Apr 18, 2008 at 06:06 PM.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Not that I am aware of. Check with the block manufacturers, directly. I think without getting ridiculous, that a 4.00" stroke in a 4.030" to 4.060" bore is about all you'll get with a Gen II foundation. You could forgo the advancements of the opti spark and the camshaft driven reverse flow water pump and go back to a Gen I.
RACE ON!!!
RACE ON!!!
Thread Starter
Melting Slicks
Joined: Dec 2001
Posts: 2,437
Likes: 1
From: Gainesville Fl
http://www.dartheads.com/products/bl...ll-blocks.html
so a block like this wouldnt accept LT4 style heads?
so a block like this wouldnt accept LT4 style heads?
Le Mans Master
Joined: Feb 1999
Posts: 9,926
Likes: 38
From: South Carolina
St. Jude Donor '03 & '05
There is 1, again 1, aluminum Bow Tie Block GM made for LT1/4 engines. There is 1 guy who has and has done nothing, absolutely nothing with it. Its probably rotting away.
But it was a 4.125 bore.
Imagine if GM had produced a normal run of those.
But it was a 4.125 bore.
Imagine if GM had produced a normal run of those.
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Race Director
Joined: Jan 2002
Posts: 12,263
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From: O'Fallon Missouri
Le Mans Master
Joined: Feb 1999
Posts: 9,926
Likes: 38
From: South Carolina
St. Jude Donor '03 & '05
Race Director
Joined: Jan 2005
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From: Slidell Louisiana
That would be a good use for your SUB PAY
Le Mans Master
Joined: Jul 1999
Posts: 8,683
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From: Phoenix AZ
There are no aftermarket LTx blocks. I tried to have one made a while ago with a few other orders but no one would do it...too expensive.
GM did make an LTx "LeMans" style block that had a lot of "meat" to it and could be safely taken out over 400ci, but these blocks were technically illegal for racing use (even though they were used). There were very few of them made and there is only 1 left that I know of, and the person that has it cannot sell it per GM.
I would love to get my hands on a 427 LTx, but I don't ever see that happening.
GM did make an LTx "LeMans" style block that had a lot of "meat" to it and could be safely taken out over 400ci, but these blocks were technically illegal for racing use (even though they were used). There were very few of them made and there is only 1 left that I know of, and the person that has it cannot sell it per GM.
I would love to get my hands on a 427 LTx, but I don't ever see that happening.
Safety Car
Joined: Apr 2001
Posts: 3,525
Likes: 2
From: Houston TX
4" or 4.125" stroke crank in a LTx factory block. 4" stroke is fairly easy (though costly), but the 4.125" stroke requires a lot more work and a LOT more money. I have built two of the 4.125" strokers, and a handful of the 4" strokers in both L98 and LTx version.
No aftermarket block alternatives.
Aaron
No aftermarket block alternatives.
Aaron
Safety Car
Joined: May 2003
Posts: 4,283
Likes: 0
From: Houston Texas
There are quite a few 409 LT's out there. Used to be a local guy here in Houston named Phil that owned CXI racing. He supposedly had a 421 LTx engine. Made some car magazine with it and "claimed" 600hp n/a and 1000 with nitrous. Engine had a drivetrain failure at 40mph crusing down the road and wiped out engine.
Safety Car
Joined: Apr 2001
Posts: 3,525
Likes: 2
From: Houston TX
Ah yes, we all remember Phil. With mom's pocketbook we could all open a shop. I never saw the car run, but he showed it quite a bit. And yes, it was in a nice magazine spread.
He was quite opposed to F/I. N2O all the way.
He was quite opposed to F/I. N2O all the way.
Thread Starter
Melting Slicks
Joined: Dec 2001
Posts: 2,437
Likes: 1
From: Gainesville Fl
guess it looks like i will stick with the 396 route in the end. simple and common enough to get that displacement. lots of parts made for it and i know it should still be reliable. and i would think if you had good enough heads on it, you could still get some awesome numbers out of it. i dont know if anyone has built a ***** to the wall LT block since AFR has re-engeneered the 227 "eliminator" series. in the right configuration they flow between 320-330 on the intake. i would think those could put out some amazing numbers if someone like advanced induction got ahold of them and put them with some 1 7/8" longtubes and the right cam
Drifting
Joined: May 2005
Posts: 1,258
Likes: 38
From: springtown Texas
i found this one for you,
Rare Rare Bow-tie Gen 2 Block Reverse Flow Cooling
http://www.ls1tech.com/forums/showth...ighlight=block
Rare Rare Bow-tie Gen 2 Block Reverse Flow Cooling
http://www.ls1tech.com/forums/showth...ighlight=block