True, but the FAST had the MSD covered by a wide margin below 5000 RPM. Just out of curiosity, what are the details on your engine? Is this a street engine or a track car? I can't see the OP's 5.7L making this amount of power. I would think his combo is going to be closer to 400 RWHP. In that case, a 90mm snout intake like the FAST 92 would be a much better choice.

 

Another bit of misguided Internet wisdom there that's very commonplace unfortunately

The runners of the FAST 102 vs the 92 are exactly the same.....same length.....same cross sectional area.....if anything the 102 has a better radiused bellmouth and is a much better from the aspect of its construction quality and overall design.

The 92 is a maze of rubber O-ring cord with the top of the intake actually representing the top of the port.....has a seam down the middle of the runners due to this design. The runners of the FAST 102 on the other hand are one piece solid runners that are inserted into the base and sealed with a single O-ring at that point

MUCH better design.....the top of the 102 is truly just a lid with a perimeter O-ring around the base that is seals to.....simple, clean and effective. Has the benefit of a larger opening and EFI cars like larger openings reducing inlet restriction which make more power. The TB's are just an airblade....you arent trying to meter and atomize fuel so with EFI intakes the bigger the TB area the better. If you ever saw both manifolds in pieces in front of you most guys wouldn't even consider a 92 as the 102 is clearly a superior design.

The ONLY reason to run a 92 on a C5 is due to better fitment under the cowl and that could be handled with lower engine mounts or shimming the cradle allowing the FAST 102 to be installed without fuss.....some of my customers have installed them in C5's without doing that....but its a tight fit and just about rubbing on the rear top of the intake directly under the firewall cowl.

The 102 is a superior design without question and it will make more power than a FAST 90 or 92 mm intake but if you don't want to deal with the added hassle of the instal a properly ported 92 still makes good gains (usually 20 - 24 RWHP over an LS6 intake)

-Tony

 

Thank you for the clarification Tony.

Couple other questions, what about a larger MAF and intake track and throttle body that maybe required with the FAST 102?

 

Your welcome....

In regards to your other questions it's always best to try and keep the entire inlet path 4" in diameter (102 mm or so).....so a Lingenfelter (or pick your brand) of 100mm MAF and a CAI that supports the larger flow path is obviously bonus but it's more needed and more desirable on higher output combinations.

What I also like about the 102 purchase (over the 92) is als better future proofing your combination....should you ever get more aggressive with it.....premium heads, larger cam etc. you haven't handicapped yourself in the future with the less desirable FAST 92

-Tony

 

Thank again Tony.

More explanation of my setup and point of reference vs the OP question. I have a set of Wegner CNC port NASCAR truck series heads that I decided to keep on the shelf. That is why I made the decision go with the TPIS 90mm snout LS6 intake, LS2 90mm throttle body and stay with 85mm MAF and '01-04 Callaway Hoonker and use the C6 LS2 factory bellows tube. The old combo with the LG Pro long tube, stock 243 heads and 230/236 .598/.603" 113 cam with a forged pistons/rod short block made 409 RWHP and 392 ft-lbs and the car spends 98% of the time on the street. The thought process was to help maximize the combo with the 90mm throttle opening. Dyno tuning results coming in the Spring. Yes I have the hood rubbing issue even with Hinson engine mounts, but I also have a stack of matching diameter SS washers on top of those mounts (net about 1/4" lower than stock currently) that I need to play with to get things optimized.

 

the graph was just a comparison between the 102 and msd for anyone interested, mine was a street car that was drove a lot and did a lot of 1/8 mile racing….it’s basically ported tfs 215 heads, lg headers and cam g5x3, Tony ported the msd, ewp, underdrive pulley, eventually made 508/440 with a little more compression, 12:1 and a vacuum pump, 93 octane, this was with 4.10 gears so I like to say it would dyno higher through the stock 3.42’s lol

 

So what was total cost for 30hp??

 

well I did the ls2 throttle body along with it so whatever the price’s were for a fast 102 and tb around 8 years ago, I can’t remember

 

Educated guess in todays $$$ would be around $3,000.00-$3,300.00:

Manifold=$1,100.00
Porting=$800.00-$1,000.00
102mm TB=$600.00
Tune=$500.00
Just a guess........

 

thats what i thought. All i would have done was put racing sound exhaust doesn't even have to add hp just the sound alone and you'll think the car is going faster. Thats what i remember in high school anyway. The big one that ever body wanted was the cherry bomb straight through.

 

Any ideas on how much of the gain is related to the larger TB size vs new manifold ?

 

Ported 92 or ported 102 (same cost) $1695

Port your LS2 TB $275 (Purchasing a 102 adds approx 5 RWHP)

Fuel rail kit and hardware (ONLY if you order a 102) $235

This should not be a $500 tune assuming you already had a tune in the car. It would not be that extensive like a complete heads cam car which changes the VE of the engine much more dramatically and requires more tuning time to dial in

Picking up HP at the wheels at this level....PAR is 75 - $100 a pony......paying less is cheap power....paying more starts to become more expensive power (what you end up paying when you have already purchased mods like this and all the other low hanging fruit)

This hobby isn't cheap.....hell most hobbys aren't but the gains provided by a properly set up induction are in line with the typical costs of "modding" and improving engine performance.....the value isn't bad at all

Honestly if your put off by the costs of this upgrade you might be in the wrong section of the forum.....LOL

Seriously though performance improvements cost money (and a bit more than they did just 2 years ago unfortunately) but if you race your car or your drug of choice is an acceleration rush it's nice to know you can make significant improvements to the output of your engine

Some folks are more than content with the power levels closer to stock and others are not, especially depending on how they use their car.....different strokes for different folks

-Tony

 

Does a 102 induce any drivability quirks that can be tough to nail down in the tune? I'm curious about off idle low throttle angle transitions and the transient fueling in particular.

 

I guess we're assuming a 30hp gain here? I didn't see any actual, or even an average number here. Tony, you've been doing this a long time. So I think any number you'd provide, while maybe not the "Gospel," is likely as accurate as anyone will ever see w/o a dyno. What do you think the gain would be when porting a FAST 102, and running a102 TB, with a tune? TIA......

 

It can if your tuner doesnt have alot of experience with the larger TB's.....recommend you ask them up front and you will see very quickly from their demeanor just how comfortable they are.

With a good tune they can drive great.....the 102 is more aimed at guys looking for all they can get from the swap naturally.....typically more aggressive combinations

It depends on the intake being replaced and also how good the cylinder heads are....the better the heads the larger the restriction the OEM intake represents (makes sense right).

With my heads most of my customers see 25 - 30 RWHP with the big TB included......last week I had a customer pick up 32 RWHP after removing an LS2 intake which is arguably one of the worst OEM intakes GM made for the cathedral heads.

Hope this helps

-Tony

 

And then there was the poor mans FAST which is the Dorman LS2. Back in the day it was ~$400 when I bought one vs the $900-1000 FAST 102.

It reportedly has the upper half runner design of a FAST with LS6 designed lower then glued together. When I "ported" which really was just cleaning up the steps between the two halves, it made more power than my LS6.

Thread here of my results:
https://www.corvetteforum.com/forums...s2-intake.html

Downside is the DLS2 is now almost the same price as a FAST lol