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I'm chasing a p0300, and pulled the intake to inspect the manifold gaskets, they weren't terrible but I noticed rtv goo in the runners. Looks like it was pulled apart a while back to be painted and the old fast gaskets were just slimed in rtv.
I have a hard time saying it's ported, these fast intakes just don't have a quality finish to them. I'd say I cleaned and smoothed all the runners.
I think it turned out pretty well for my first time. I need to get some assorted sand papers, I have 80 grit and 600, and I need to get some in between papers and smooth it out
Let me know what you think
Last edited by chrysler kid; Jul 8, 2017 at 01:13 AM.
Yeah that's probably a smart move being your first time.
There's no way I could port match the runner exit to the head. It takes a lot of precision to do those flat pieces. I used 80 grit to sand them down quite a bit, but those flat exits are not to be messed with unless you know your ****.
Looks to me you just used good ol' common sense and sanded away the "hiccups" in the manifold ports. There HAS to be some improvement in what you did. Give us a "butt-dyno" report ASAP! lol Inquiring minds(AKA nosey ones...) gotta know!
I'm waiting on my gasket kit from Texas Speed. I placed the order Thursday night for next day delivery, they called and said they need to order it directly from fast. I was assured that it would arrive on Monday. I have to get the car running to take to Michigan, if they don't come through I'll have to get messy with rtv again
It was reported back as a 10hp gain just to smooth the runners and clean up the surfaces to mate better. With my .595 lift cam 10hp seems like it should be achievable.
Originally Posted by Slowhawk
The porting work is very nice and clean. There is more to port in the 90mm though
You did what I call a stage 1 port job -ussually $150 . Stage 2 is that and direct porting to the heads -$250 and then there is a full port which shortens the runners and short turn radiuses,mostly for bigger cube motors -$450.
I remember getting one of the first 78mm's when they came out.First thing I did was grind the runner's like you did thinking "hope this doesn't screw up the intake". That gained me 20rwhp too from a stock LS6.
Last edited by chrysler kid; Jul 8, 2017 at 01:58 AM.
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Ported my fast 78 
