Negligence

http://marylandspeed.com/fast-102mm-...acturers_id=43

I've seen this intake manifold mentioned on a few threads, is anyone running it currently and have any thoughts on personal experience?

What Throttle body did you pair with it?

THanks

Naf

iTrader: (1)

you need an engine larger than 6.0 to take advantage of its volume.

I have it ported on my 6.8 and i will never look back at stock again...

rand49er

Unless you're blowing a lot of air into your motor, this probably isn't going to improve its performance.

Naf

iTrader: (1)

If you are blowing air, then this is a waste of money.

If you need a large volume of air then yes go for this, but unless you have a massive cam, ported heads and pushing more than 500rwhp this would also be a waste...

forgot to mention 102mm TB...

Negligence

I plan on doing Heads and Cams with the car but not an extremely aggressive head.

Am I better off than with the 96mm sized Intake Manifold?

NIKDSC5

iTrader: (10)

I see you're new, so welcome.

Now, let me introduce you to the sticky section, and search function.

Both reside toward the top of the page, and both are exponentially useful at answering questions such as yours, and eliminating worthless threads. Such as this one.

When all else fails, let google be your guide.

rand49er

Just theoretically speaking, the plumbing which constitutes the passageways for airflow into, through, and out of your motor has only one constraint to volume flow at any one point in time. Enlarging the ports in the heads may help as will larger valves and longer opening times and as will better/bigger exhaust passageways. Minimizing turbulent flow will help, too.

Admittedly, I have very limited practical experience to draw on, so I can't provide good counsel here only to be careful and only listen to trusted/reputable sources of where to spend your money.

D.K

iTrader: (1)

I run the Fast 102 with an LS2 TB on my H/C V and I like it. Unfortunately I don't have any before comparisons since I installed everything at the same time, but I'd purchase it again. I was initially torn between the Fast and the Edelbrock intakes, but my cam selection prompted my choice of the Fast. It does everything the LS6 manifold did, just a with the ability to add more capacity. The only thing that I'm remotely sure of is that it does seem to transfer more noise than the LS6 manifold did. Not really a positive or a negative...just different.

itsslow98

iTrader: (18)

If you are doing heads/cam then it may be worthwhile. It all depends on how you feel about dropping a grand for 10-15hp in the upper rpm range.

DACTARI

iTrader: (1)

I had tuning problems with the FAST 102 on my cam/headers LS2... hanging idle, surging, etc. Was a bitch to tune out and never got completely tuned out.

Jezus

What tb were you using dactari? I have an ls6 with ported heads, cam, headers and everything and this is next for me. My tuner said I could have those same issues if I go with a fast 102 but I think he was meaning a 102 tb, not the intake. So ive been leaning towards the 92 with an ls2 tb but don't really want to deal with drivability problems so im not sure what to get.

Pray

iTrader: (7)

Same question from me. I have never had an issue with the Intake but have had some small issues with the TB. Did you have the issues with that cam before you put the FAST on? There are some tables that have to be tailored to run a 100mm TB. Some are not so obvious.

I will say that from the factory the LS2 intake is the biggest piece of crap out of all the GM manifolds. I have an idea what they were thinking when they designed it but it is hot garbage. I port a lot a manifolds and the LS2 can be made a ton better but I would still vote for he FAST. Surprisingly the second worst manifold is the LS7. I don't think you can cram too much air into the front of the motor. The heads up to about 260cfm will be your biggest restriction. There is a transient point from 260-280cfm but beyond that the intake and what is in front of it becomes the restriction. The other factors is cam selection for runner length and cross section. I have made over 400rw with ported LS2 intakes and bolt ons so they are capable once they are opened up and some things sealed up in them. The FAST won't net you gains though until it is needed. So if your current manifold provides enough air for the heads and cam you are using then you are wasting your money. For mild cars I would suggest a ported LS2 intake and ported LS2 TB.

I am trying to reconfigure my flow bench so I can start bolting on manifolds once I am done with a set of heads to quantify flow improvements of the intake. I don't think I have seen a motor that lost power by going to a FAST. If someone has some dyno graphs to show the differences I would like to see them.

The other proof to this is looking at rectangular port heads vs. cathedral port heads. I think the biggest difference in power between the two is the intake manifolds. The rectangular port heads flow a ton more air on the intake side but are limited to what intakes we have on the market right now. The intake is really the bottle neck. It doesn't matter how much intake air your head flows if all of our manifolds are limited to say 300cfm. The exhaust runners between the two heads are almost identical when it comes to flow so the amount of exhaust air getting out does not effect the over all power numbers between the two style of heads. I think the intake manifold is also the reason why you can run a cam all the way down to a 6* split and see about the same power if not more then cams with say a 15* split in LS3 combos. A lot of guys think since the head flow numbers and intake vs. exhaust flow percentage is down in the low 60% range that we need huge splits. But once you bolt the manifold on that ratio bumps up into the 70% range. That is not to mention if we take exhaust flow numbers with a pipe attached like they would be running in a car and the effects of scavenging. In the end it is a sum of the whole combo. Not just one part.

DACTARI

iTrader: (1)

It was the stock LS2 TB. The cam was a big split cam. You can see the grind specs in my sig. It was fine with the LS2 intake, but the FAST 102 just made it go nuts. I suspect there was some kind of interaction with the big split cam, like maybe it caused some turbulence or something. I really have no idea. Some of these combos have this issue, some don't. The only thing I can note is that most cams didn't run the same kind of split that mine did.

Pray

iTrader: (7)

Interesting. The only problem like that I have experienced was with a cracked Fast that was causing a vacuum leak. It took forever to find. Had to use a smoke machine. It was tiny to.

Jezus

Ok, I have the tick sns torquemax stage 2 cam 227/235 61x/62x 110+3 so would that mean I might have the same issue? I don't think I need the 102, I would stick with the 92mm and ls2tb or maybe the fast 92tb

Pray

iTrader: (7)

No, you will be fine. Just ma km r the proper tuning adjustments.

4doortypels

iTrader: (39)

The best question is what ls is this guy running? Ls2 vs ls6 gives different head selections... ls2 id l92 with a mild cam and save money on porting. L76 intakes flow very wells. Heads cam tune under 2 grand if heads and cam are installed by the owner of the caddy. Ls6 me personally id buy some cnc stockers, matching cam, and fast 92 and ls2 tb. That second combo would be closer to 3k plus tunning.

DACTARI

iTrader: (1)

That was just my own stupid theory. A tuner/builder would be the best person to ask.

Have you done heads yet? Much more bang for your buck.

Jezus

Yeah I have ported heads already, so intake and tb are about all I have left that I can do haha

Pray

iTrader: (7)

I just made 455/420rw with that cam 1* advanced with home ported 799's, stock ported intake and TB in a stalled TBSS so you will be good. Truck drove great and averaged 16+ mpg.