Which fast intake?!?!

[Octavain]

I'm in the process of picking out a new intake from fast. But which one, 90, 92, 102? I currently have a '98 LS1 motor but my future plan from my '98 Camaro is to build a 6.0L. I currently have the stock ls1 intake.

[egod]

besides a 6.0L what are the plans for the motors use? I would say if you plan to go on the more extreme side get the 102 manifold but go with the smaller tb till you get there. if you get a tb and manifold that is too big you will sacrifice throttle response. You can regulate that with tb size. If you get a smaller manifold and a big tb it won't make much of a difference because the manifold is the last opening.

[Octavain]

besides a 6.0L what are the plans for the motors use? I would say if you plan to go on the more extreme side get the 102 manifold but go with the smaller tb till you get there. if you get a tb and manifold that is too big you will sacrifice throttle response. You can regulate that with tb size. If you get a smaller manifold and a big tb it won't make much of a difference because the manifold is the last opening.

What I really plan to do with the '98 ls1 motor besides get a new MAF, TB, Intake, Headers is nothing. I figure the old '98 ls1 is to out of date to really considering doing any real heavy moding. It suffers from the early gen III engineering, great motor at the time hands down! But it's 13 years old! For the 6.0L that's a little further down the road. I won't be even touching that really until I'm stationed somewhere. But the 6.0L will go in my '98 Camaro and will be a weekend warrior.

[c5z28]

Some people are making over 500rwhp with the ls1 stock cu". If you aren't going to even add a large cam it isn't worth the money for the fast.

[Octavain]

Some people are making over 500rwhp with the ls1 stock cu". If you aren't going to even add a large cam it isn't worth the money for the fast.

I don't doubt that people are making over 500hp on the 5.7. But the earlier Gen III epically 97-98 have some negative setbacks like the drilled oil cavities for oil to get to the back of the block were drilled and on 99 and later had a big open cavity for oil flow. Also the connecting rod bolts are rated 450hp on some of the earlier ls1. One advantage is though 97 and 98 maybe 99 have a higher lift on the came than the later models

[egod]

you were asking because you plan on taking that manifold from the ls1 to the ls2 right? what are your power goals and.or 1/4 times? that will determine if you want to go up to the 102 or just keep it at the 90/92 level

[Hi-Po]

The major disadvantage to any 98 LS1 fbody is the PCM. The amount of little quirks and problems the computers have seem to be never ending. That said, yes the 98 rod bolts are known to be weaker then the 99+ years. Depending on what year 6.0 and what model (LQ4/LQ9) you may not make much more power at all without adding a camshaft. Your at least looking at upgrading the heads when swapping the 6.0 to gain much power, at that point not swapping the camshaft is foolish.

FAST 90 is not in production anymore. Only option is to buy used. As far as I know, the 92mm is also being fazed out as well. The difference between 90mm and 92mm FAST intakes is a good debate, but hardly ever notable. The main, and maybe only difference being the mouth of the intake. The intakes are extremely expensive, with slight amount of horsepower gained over a LS6 intake on a stock head, stock camshaft engine. Money could easily be spent elsewhere with greater results. Simply swapping a 6.0 wont gain a large amount of power for the work/time/money involved.

To answer your original question though, FAST 92mm would do fine. Again though, not much of a power gain over a LS6 manifold with stock heads and camshaft.

[Octavain]

you were asking because you plan on taking that manifold from the ls1 to the ls2 right? what are your power goals and.or 1/4 times? that will determine if you want to go up to the 102 or just keep it at the 90/92 level

The goal is low 11 seconds in the 1/4. I also autocross and would like to run it on road courses.

[Octavain]

The major disadvantage to any 98 LS1 fbody is the PCM. The amount of little quirks and problems the computers have seem to be never ending. That said, yes the 98 rod bolts are known to be weaker then the 99+ years. Depending on what year 6.0 and what model (LQ4/LQ9) you may not make much more power at all without adding a camshaft. Your at least looking at upgrading the heads when swapping the 6.0 to gain much power, at that point not swapping the camshaft is foolish.

I do plan on doing work on the heads and a cam for the 6.0L. But I don't plan on doing any head and cam work on the '98 the heads have some minor flaws to them compared to the later heads and ls6 heads. Might do a cam.... but couldn't go to radical because then I'd have to possibly upgrade the valve springs, and one thing leads to another new rockers, pushrods.... I guess I could do all this and keep the stock stuff when I pull the motor put it back in and sell it.

Reason why I'm considering a fast intake is because I have the stock ls1 intake, sure I can pick up a used ls6 intake for around $350; but why spend that when you can spend an extra $300 to get something better that has more options for you later down the road.