Intake Manifold Swap(most call LS6)

[Uglymarine]

Hi guys, I have a 1998 A4 Corvette. I'm going to buy one of the new design Intake manifolds. Most call the new design the LS6 or Z06 Intake Manifold. It comes with gaskets, MAP sensor, Cable bracket, fuel rail, coolant tubes, coolant block offs and mounting bolts. I have read many posts regarding the LS1 coolant crossover tubes not fitting under the LS6 intake manifold. Some remove the LS1 coolant tubes and use the supplied coolant block offs for the rear and the supplied coolant tube for the front with the new manifold. Others retain the LS1 Coolant crossover tubes under the manifold by removing the ribs where the tubes would interfere so that the manifold lies flat. Which is the better method to retrofit the LS6 intake manifold to a 1998 LS1 engine?..............Haven't posted in a while. I stopped by now and then to see if the pig needed feeding but never saw it. I hope everybody is well.

Interesting that I saw something about the #7 cylinder problems on CM while trying to find answers about what is best to do. Just after posting my question above I stumbled on the following on another site on this very question:

Here's the stuff I remembered from Kurt on Tech. I believe he made a similar post on performancetrucks.net, but I can't find it today. It's not quite the same as I remembered


Quote:
Originally Posted by Kurt Urban
We ran the tubes in the Motorola cup cars because if we put the back plug types in the #7 cylinder would have problems. It seemed to me with the testing we did that air pockets formed in the back of the head from the coolant boiling causing the engine to detonate on the back cylinders. Normally #7 would eat the piston or break the rod and #8 would show signs of trouble. These are just guesses on my part based on what the parts looked like broken!
One thing I did in the late 90's was put thermocouples on the 4 corners of the heads with the water still flowing. Then we put 10 02 sensors in, one in each port and one in the collector of each bank. I then parked the engine at 6500rpm/full load for 15 minutes at a time with the intake on normal and reversed to record coolant temp and afr. Nothing showed up that clued us in on why the 7 cylinder was fragile. The engine was a stock stroke forged piston Motorola cup legal LS.
Around 2000 or 2001 Unocal started sponsorship of the Nascar stuff and the Motorola cup could no longer use 94 Sunoco as the fuel on Union tracks, this forced them into 100 octane and the number 7 problems went away so we stopped looking for why....


Kurt

This is from post 24 in this thread on another site.

Kurt does go on to say that they run the tubes on anything high powered, but that a street car may never boil the coolant anyway.

[c4c5specialist]

HI there,
GM uses the front crossover and installs plugs on the rear bleed points.

That is how it should work.

Allthebest, c4c5

[ToolGuy]

Yes my SLP LS6 intake kit came with the block offs, I used them and have not had an issue.