badazz81z28

iTrader: (6)

Folks, after looking for a used 90/92 FAST intake and being shocked by the used price tag, I inquired about a FAST 102 for cathedral port heads. The information I got from them is the FAST 102 will accept 90 and 92mm throttle bodies and will perform better than the old designs. From this information, make me think...The rumors and the urban legend that the FAST 102 is too big for an LS1/LS2/LS6 is not really true at all.

What do you all think? I think it would nice to kill this rumor and see the old FAST intakes come down in price. As it looks now....For $800 Im buying the FAST 102

01ssreda4

iTrader: (96)

90s are going for stupid prices used. I saw one go for 550 today and it had a big hole in it. I won't be buying these stupid inflated prices for them. I'll go 102 new.

Tony Mamo @ AFR

iTrader: (13)

There are endless threads on this topic.....you really should use the search feature.

Long story short the 102 is a better design than the original 78/90/92 mm series which were all essentially the same exact intake with different sized TB entrances.

The 102 is not better by virtue of its larger TB opening btw....its a clean sheet design with removable runners that sit in the new base with an O ring seal around each port. The 102 also features a much more rugged build quality (its actually 3 lbs heavier which is significant when we are discussing a plastic intake). Gone is the 100 miles of internal rope seal that was a nightmare to deal with if any of the older design manifolds came apart.

The runners are more optimized with better (improved) radius'ed entries and a more desirable shape and cross sectional area thru the entire port (the manifold is also taller btw and they use the additional real estate to help create a better port design). The outlet of the manifold is also much less compromised than the original.

Out of the box to out of the box the 102 manifold is clearly better offering more performance potential. But whats even better is the new design allows me more freedom from the aspect of further porting and modifying for even greater results for the guys wanting to get the most from the install. To be honest I used to take a little more material out of the older design intakes but now I'm actually removing more (in different locations) from the new design (102 mm versions) but the end results are far superior when I test an intake port of a good cylinder head thru one of my 102 ported intakes versus one of the older 90/92 mm intakes. There is no comparison....I'm seeing 10-15 more CFM net to the cylinder (on a 350+ CFM head like the AFR 245) thru an optimized 102 than I ever saw with the ported 92's I used to work on. The main reason that's possible is the different construction/design of the 102 affording me more "freedom" with the grinder.....I would have put a hole on the older design intakes in areas I'm purposely getting aggressive with the new design 102 piece.

If your going to take the plunge the 102 is the way to go and Im not even going to get into a long diatribe on the largest Internet myth out there ("its too big for a 346"). Bottom line the size of the throttle opening could be 200 mm......it doesn't matter because we are just moving air, not trying to atomize fuel (thats where the myth comes from....old school problems of carbs too large to be effective). What really matters is the length and CSA of the runners and they are more than acceptable for a deep breathing 346 (especially with an aftermarket set of heads) and much larger motors as well. Its a very flexible design and its really hard to beat for your typical street strip applications.

OP.....I would still encourage you to use the search feature.....I have written volumes on this topic as well as a handful of other sharp members on the board also. There is alot of info to digest and better understand if you have the time to read......the hardest part is knowing who to listen to but if your reasonably sharp you should figure that out fairly quickly.



Regards,
Tony

cranny

And be prepared to buy another $800 worth of parts to get that 102 working optimally.

01ssreda4

iTrader: (96)

Tony,

1. Do you feel the porting of a 102 is "worth it" with stock head castings that have been CNC'd? Or is an out of the box 102 sufficient for those more budget builds?

2. Based on what you wrote, do you feel on your average H/C car the Fast 78 is a worthwhile investment? They seem to be a lot cheaper then the 90s.

BrntWS6

iTrader: (7)

How do you get $800 in parts on top of the manifold, TB and fuel rails?

cranny

The manifold is $800

Then
MAF $200
Thottle body $300
Fuel rails $150
Bigger lid $150
LS2 water pump $150 (if you don't want to grind your LS1 pump)
Bigger couplers to join it all together? $50
It should be dyno tuned again $500

It adds up.

TransAmcoupe98

iTrader: (10)

Myself and Lemons12 installed one of these on his T/A, the FAST 102 was an absolute ***** to put on with engine in bay. The back bolts were damn near impossible to tighten down or to get a tool back to them. However, I'll be damned if I pay 1000 bucks for a FAST 90 that they probably payed 900 for. The 90 or 92 intakes should be reselling for 700 MAX...

Tony Mamo @ AFR

iTrader: (13)

Its worth it....look in the beginning of this thread for the gains this guy saw with STOCK heads (LQ9.....basically low compression 243 castings). Granted, this was a ported FAST truck intake I did (which is slightly better than the car version) but I assure you that you don't see these types of gains with a stock FAST truck intake with stock heads....no way no how.

https://ls1tech.com/forums/dynamomet...230-heads.html

I seriously rework these new design manifolds and the results of the extra modifications pay dividends.

A stock FAST 78 is worth 7-10 HP....barely enough to feel. A ported 78 (properly done) will get you closer to 20 (with decent heads).....that's more easily felt. A stock 102 will get you closer to the results of a ported 78 than a stock 78 but modified properly you can see in the neighborhood of 30 RWHP and even more in front of a really honking set of heads (like an AFR 245 etc.).

The FAST 102 swap is involved and its not cheap all said an done, but if your looking for gains more normally associated with a head swap, why wouldn't the price of admission also be close. Its not a horrible investment on a pony per $$$ increase....in fact its kind of on par for most other mods besides a cam swap. You just have to be willing to fork out the serious dollars to get the serious increases one of these optimized set-ups are capable of.

If your serious about getting the most from your ride its a no brainer....if your serious about getting the most from your ride and you cant afford it save up longer and then do it....it would be worth the wait and you wont spend money twice like so many of the guys on a budget ultimately do (the irony being they spend more in the long run).

Seriously, the guys that whine about the cost should whine about every other mod they do that costs money. Figure out what your really getting at the end of the day for the dollars spent and it starts to open your eyes a bit as to what's good value, so-so value, and not so good in the various things you invest in to improve performance and keep in mind that once the easy big bang for the buck items are off the last, your left with lots of options that look on the expensive side....and that keeps getting worse with every mod that you add.

-Tony

SF 1HOTLS1

iTrader: (24)

and an electric water pump. but people grind the stock ls1 pump to clear the intake/tb. i heard using an ls2 water pump works with no issues as well.

SF 1HOTLS1

iTrader: (24)

2. Based on what you wrote, do you feel on your average H/C car the Fast 78 is a worthwhile investment? They seem to be a lot cheaper then the 90s.[/QUOTE]

Wouldn't a fast 78 make just about the same as an ls6?

01ssreda4

iTrader: (96)

Well by what he said, internally the 78/90 are identical. I realize at some point the smaller TB will become the restriction for an air hungry engine. I have seen tons of 78s floating around for sale but never bought one because I always felt I would regret it later (for not going bigger). I refuse to pay $800 for a used Fast 90 when 102s are $850 or whatever. You can skip the MAF by going SD and any decent lid will probably be fine as the gains are in the intake design (from what I gather). Seems like I've seen good results with the 102 coupled with a 90mm TB showing the TB is not the restriction.

salemetro

iTrader: (5)

All I can add to this, is my personal experience with the 102 over this last weekend.

L33 5.3 with ported heads in the neighborhood of 300cfm...Fast 102 (un touched), 90mmtb,90mm MAF,Fast 36lb injectors, and a pretty mild EPS cam (.595/.600 113+3) netted me 379rwhp and 354rwtq in my daily-driver Miata. That was with timing in the neighborhood of 24*@wot, and AFRs at roughly 12.5 in PE. Needless to say, I'm very happy with the results for what the car is....and we know that there's still a bit left on the table. This car has EXCELLENT street manners, and pulls like a freight train for a little 5.3.

I say all of this because I was a little concerned with changing out from the old ls6 intake to this one....thinking that it might be "too much" for the 5.3. I even had a couple of doubter friends that thought I'd loose a ton of low end/midrange power. Let's just say that they are now pretty impressed with the results. I say (as has been already pointed out here)...GO WITH THE 102. You won't regret it.

SweetS10V8

iTrader: (4)

Extremely common misconception, the sticky should be explaining how TB size doesn't have anything to do with "too big, too small or just right".

I have also explained a ton of time how its the internal runner that creates the velocity to the port. Where people confuse it is when they think like a carb. A large carb would have low velocity or signal. Since a carb fuels from venturi in the openings, it requires a good signal to pull fuel. So a carb that was too big would be mushy.

These engines are fuel injected and have the injector firing directly at the valve and therefore don't have to have signal at that TB opening.

Here is a visual for everyone!!!!

Notice after the TB opening the air in the plenum doesn't have much velocity (blue), and you can see how the runner creates the velocity to the cylinder head (red, yellow, and green)

dr_whigham

iTrader: (49)

I'm installing my 78 when I get home next week. I get to keep my injectors, my fuel rail, MAF, Lid, and most importantly, my TB.

I personally feel the 78 was worth it based on the price. I'm coming 100 bucks out of pocket after I sell my LS6.

When the time comes and my heads outgrow my 78, I'll pass it on for the same price I paid for it. I was INSTANTLY turned off from the 90's and 92's from the price. Sickening, to say the least. I for one will be passing on the savings when it IS time.

SweetS10V8

iTrader: (4)

Smoking deal, youll enjoy it!

It is a little crazy how much people are getting for them right now.....Supply vs. Demand.

BrntWS6

iTrader: (7)

Ok, your including the TB and fuel rails. Only reason I said with that stuff is because he can get all that new for the $1400 he was going to spend on the 92mm setup. It definately does add up though.

- You don't need a LS2 water pump with a 92mm TB
- you can get 90mm GM MAF's for $40 on E-bay all day
- mail order tune $150

dr_whigham

iTrader: (49)

Just saw an ad in the classifieds someone was selling a 102/102 combo WITH fuel rails for 1050......

thunderstruck507

iTrader: (18)

In the past Tony has said the 78mm should be within 5hp of the 90mm on what I seem to remember was a full bolt on or cam only car.

People have also opened the snout to accept a 85mm tb with good luck.

If it's a good deal I wouldn't be afraid of a 78mm Fast.

Rickenbackerman

iTrader: (1)

Huh, I didn't have any problems at all... You just need the right length extensions.