FAST Intakes @ Thunder Racing...THEY'RE HERE!
something is causing a bottleneck on the big cubed motors as most expected the LSX would shine the best with the big cube motors but the initial tests have shown the best gains on stock cubed LS1/6 motors. Give it a little time to get the bugs worked out and figured out what's the bottleneck and hopefully the LSX intake will bring a solid 20rwhp minimally, for us big cubed guys!
Only time will tell and i will just kick back and see what happens! First off, thanks for doing all this work so fast!!!!
Now, I was wondering if you can hook up a manifold pressure gauge to the LSX on the Shane's 375 motor? If the TB is really the restriction, I am thinking you should be able to see some vacuum pulled. I have seen the posts about the big cube motors pulling some vacuum on the LS6 intake in the higher rpm ranges. It would be interesting to know how that compares to the LS6 intake(not that I am trying to give you guys more to do.
). Todd
That would be an excellent test bed for high rpms and big cubes. Also, as posted earlier did you check for vacuum in the upper rpms? When you do the math 90mm TB should support a 427 Cu in motor all day long. I would think a 78 would be enough for under 400 cubes.
Thanx for all the quick results TR. You guys are on top of it!!!
The car is a 2000 SS w/ iron block (375 ci), Stage 2 heads, big cam, all the bolt-ons, headers w/ bullet mufflers. He swapped from an LS6 intake to the FAST...no other changes were made. Before & after runs were made back to back and the intake was changed w/ the car strapped down on the dyno. Unfortunately, I don't remember the exact numbers, but the end result was a gain of 7 rwhp. I'm really curious to see if the bottleneck on these bigger motors is with the 78mm intake...possibly the 90mm intake & tb combo might be the answer for these cars? We'll be testing more as soon as we get some of the 90mm tb's in. I will post Shane's graph first thing in the morning.
Angie
I am excited about the intake but 7rwhp is not going to justify the cost, for now Ill wait to see more results.
Mikey
The tb on Shane's car is one of our CNC ported ones.
Angie
The Best V8 Stories One Small Block at Time
Mikey

Angie

You could get a scaled 90mm Pro M MAF with the FAST intake and 90mm T-body, smooth bore tubing and then a big bejesus coned K&N in the hole underneath where the battery used to be.
That would likely eliminate all restriction and probably pick up 30+RWHP on a big bore/stroker vs stock ported T-body and LS6 intake.

I'll be most keen to see the results from the 90mm version as I own a 428 CID and find that the LS6 manifold is starting to stuggle with the demands placed on it ... that and we may have been a little conservative with the 242/242 with very tight lobe separation we initially installed.
We are now going with a 252/260 with wider LSA and would like an opinion on whether this manifold will work well with it.
Note to the car has a mafless tune (as in the HSV GST300 - a very popular mod here in Australia) and takes it's airflow data from the MAP sensor. This removes the MAF constriction some are worried about. Custom formed 90mm smooth rubber pipes take air from the front air dam to the airbox and on to the TB from there.The only thing I need is a 90mm TB ...I have an 84mm unit at present.
Did someone mention that 90mm TBs aren't a real flash fit on the manifold? why's that?


