03 BUSA

iTrader: (25)

Heard from a good source that Fast has tested their new L92 intake and it did not work. Don't know exactly what went wrong but not what they expected. Anyone else hearing anything about these intakes yet? Might have to find someone to port the L76 intakes. Fast please say it ain't so. I know alot of people are waiting on this design.

CHarris

iTrader: (5)

Hmm.... Lots of people are waiting on that intake manifold. The cathedral port FAST tood advantage of a raised runner and a straighter shot with the runner. I think it would be a bit harder to try the same old trick with this rectangle port. It would have to be a good deal taller I would imagine. Theres not a lot of extra height under most of the GM hood lines.

I can help you on the ported stock piece if you decide thats the way to go.

03 BUSA

iTrader: (25)

I will def keep that in mind if I choose to do that. How much have you seen in gains porting these intakes.

WKMCD

iTrader: (2)

That's bad news - if true - about the L92 FAST. Here's a before and after on the ported L76 intake done about a month ago.

https://ls1tech.com/forums/showthrea...662314&page=20

OnyxSilveradoSS

iTrader: (4)

I believe it. They are just now getting the lower manifold right for the L92 Maggie kit, these things are super new and you cant rush R&D.

thye will get it right, there is too big of a mraket for them...just how long can people wait.

VortechC5

iTrader: (6)

The Fast rep that I spoke with at SEMA told me that they were having a hard time making more power than the L76.

MattDZ28

iTrader: (1)

If it ain't broke, don't fix it!

BlownVette 2001

iTrader: (2)

That really depends on what you are doing. The L76 quits at around 6200 rpms, if you need to spin faster you need a cure.

03 BUSA

iTrader: (25)

Exactly. And it seems that porting the L76 on the larger ci motors is doing nothing but costing money.

GoFast908Z

iTrader: (12)

Some flow data from my tuner shows it stops flowing around 6800 or so.

BlownVette 2001

iTrader: (2)

Well if you got some info, why not share it ?

There have been quite a few other post that about the L76 and it's limitations. That's why you see all of the aftermarket vendors trying to provide a solution.

I would go for a 427 with LS7 heads and LS7 manifold myself as it's a proven combination for big bore set-ups.

SS Enforcer

Mine peaks at @ 6500 and only drops about 10hp from there to 6900. We think the trick is in the exhaust flow.

cheers

CHarris

iTrader: (5)

Wrong... However, the gains from porting are not necessarily greater on a 402 than on a 6.2 or 6.0.

BlownVette 2001

iTrader: (2)

Is the exhaust flow improved via a cam (longer duration / lift) ? or a bigger exhaust pipe (i.e. what size pipe) ?

03 BUSA

iTrader: (25)

Prove your theory. I have seen it do nothing on larger Ci motors. Maybe the porter but I doubt it. Would like to see some proof if you are going to say I am wrong and not what your buddies have told you.

edcmat-l1

iTrader: (10)

LOL Its not what his buddies have told him. He OWNS LS2portworks. All he does is port manifolds and throttle bodys. We've used his manifolds with pretty good success on several builds. I have one of his LS7 manifolds going on a build later this week or next. And another L76 going on a motor bound for Europe.

SS Enforcer

Pipes are 2 1/2 and the heads are WCCH ported L92's. Richard puts work into getting the exhaust to flow well and I think that may have pushed the peak up a bit.

Mods are in sig.

BlownVette 2001

iTrader: (2)

Thanks for the info. I got a year or so before I get to the motor, so I'll keep a watch out for more developments. Better (cheaper) for someone to work out the bugs for me.

Been working on the body, interior, suspension and drive train mods for the last three years on the vette. Hope to get the vette back up and running for a few months to work out all of the kinks.

Then we'll tackle the motor.

Steve Bryant

iTrader: (1)

Guys,
The new FAST Intake is set up for their new 92 mm throttle body and is designed for the cathedral port Gen III heads, not the rectangular port L92/L76 heads http://www.fuelairspark.com/WhatsNew...kemanifold.pdf. I think that you are trying to compare apples to oranges. Also, I wouldn't draw any conclusions until an independent lab like Westech tests it for one of the magazines. I'm sure that there will be a comparison article within six months. It's the same thing with the new Wieand/Starr Streetfighter Manifold . . . wait until the production pieces come out and look at some factual testing (preferably from more than one source) before jumping to conclusions. We'll know more about all of this stuff within a few months.

Steve

VH5150

Do you aussies have a better version of the L76 manifold?? Kinda like the FAST manifold that is mentioned?? I know you guys have stuff way before we do.. In most cases...