arsss1

I was just wondering if anyone can help. I have a 97 m6 that is bone stock. I was wanting to know if the lt4 intake was better for my car vs. a stock ported intake. The plans are a 383, afr heads and a cam. I have no clue on a cam either so maybe someone could shoot some ideas my way.

Dave89IROC

LT4 intakes are hard to find now, and are going for $700+

if needed, your intake can be welded and ported, for good flow(btw, all the LT4 one had over the LT1 one , was it had more meat for porting)

Dan Parker '96

The LT4 intake is exactly the same as the LT1 intake other than having the ports relocated 0.10" up to match the LT4 head ports. There is also a bit more meat in case you want to port it.

arsss1

So with my stock intake can I still have it ported to a 58mm tb with no problems? I also want to do a stage 3 port job on the runners, will I run into a problem there.

Injuneer

There is no difference between the two in the throttle body mounting area, so you can go 58mm on either the LT1 or LT4 intake. An LT1 intake can be opened up as much as an LT1 head can be opened up. The LT4 intake simply adds more metal at the top, so it can be ported to match the taller LT4 head runners. The extra metal interferes with the valve cover rail on the LT1 head, so you would have to machine either the LT4 intake or the LT1 head to bolt the two together, with no advantage in doing so.

veee8

Can the lt1 intake be used with good results on ported lt4 heads? Will gasket matching and blending work. I didn't realize the lt4 intakes are not available anynore. I hope I am not screwed!

Dave89IROC

yes, building up the top of the port(w/welding) might be needed

veee8

Anybody have any pics of welded and modified LT1 manifolds?

HardcoreRM125

If the intakes are getting expensive, the heads arent gonna be far behind ...

96capricemgr

My understanding is the ports ARE NOT RELOCATED but just taller in the heads and the LT4 intake ports(in the intake) are identical to the LT1 so the top of the head port os blocked by the extra material. I have seen some pics of the gasket held up to each the head and intake and it showed it VERYwell. If I can find them I will post.