thnx for the info guys.. 
My custom ported FAST 85/85 - *PICS!*
Launching!
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From: searching for the perfect driving line
I'd like to hear what the sponsers have to say. Production cost would be less if that was the only difference. I don't know how the intakes are made but I would think it would be cheaper to make all the runners the same and only change the TB hole. More than likely the intake is made in some kind of mold, so I would think only having one mold would be cheaper, both in R&D and actual production. Less variation=less expense. Just my $.02 anyway.
Thread Starter
Joined: Apr 2006
Posts: 3,910
Likes: 1,158
From: Grand Rapids, Michigan
This intake was actually one of the first FAST intakes ever made. When they came out, no one made a 90MM TB for them, so they had a 78MM opening for use with a stock TB. Eventually, people started needing a larger TB so they introduced the 90MM. I have looked at them both and I cannot see a difference in the two aside from the opening. The cost in tooling to have larger runners on the 90 wouldn't make sense from a manufacturing standpoint. It's also obvious that they're the same simply because you can bolt a 90MM top onto a 78MM base with no fitment issues. If a 90MM had larger runners this would not be the case.
It's also obvious that they're the same simply because you can bolt a 90MM top onto a 78MM base with no fitment issues. If a 90MM had larger runners this would not be the case.
Its the same internally guys....
FAST gets a premium for the larger opening which anyone can swap to who owns a 78 mm version by purchasing a new "top" which includes and changes the front snout. Assuming no leaks with the opened 78 mm discussed, it is a cost effective way to narrow the gap between the two which is only about 5 HP anyway. My 78 mm ported FAST (with a ported 78 mm TB) was worth 20 RWHP in my original 346 combo.....the ported 90 set-up netted me about 25 RWHP.
Even unported the delta between them is pretty similar.....
Hope this clears up a few things.
Tony
FAST gets a premium for the larger opening which anyone can swap to who owns a 78 mm version by purchasing a new "top" which includes and changes the front snout. Assuming no leaks with the opened 78 mm discussed, it is a cost effective way to narrow the gap between the two which is only about 5 HP anyway. My 78 mm ported FAST (with a ported 78 mm TB) was worth 20 RWHP in my original 346 combo.....the ported 90 set-up netted me about 25 RWHP.
Even unported the delta between them is pretty similar.....
Hope this clears up a few things.
Tony
Thread Starter
Joined: Apr 2006
Posts: 3,910
Likes: 1,158
From: Grand Rapids, Michigan
If someone has a 90MM and can measure, I took some measurements of my 78MM. The runners at their widest point vary from 63-65MM. From the black lower base to the highest point of the runners (basically the height of the upper intake) it is 92MM. As far as I can tell by just looking at a 90MM, there is no difference.
*edit* Thanks for clearing up the confusion, Tony.
*edit* Thanks for clearing up the confusion, Tony.
Last edited by LS1Formulation; Mar 15, 2007 at 09:37 AM.
Consider this in your search for "value" (I look at everything on a HP per dollar basis).
If you already have a good epoxied and ported 78 mm TB (like a Mark Shaner piece or something similar) score a 78 unit cheap and just consider having it ported. Even at the prices I charge to do a very neat and thorough job your return on investment is still better than buying a larger 85 mm TB and cutting up the snout which might close the gap in half between the 78 and the 90 netting you 2-3 HP. For an extra few hundred you would see an additional gain of 10 RWHP and a similar bump in TQ (my ported FAST 78 set-up went 20 RWHP and 15 RWTQ stronger than my former LS6/78 set-up as I previously mentioned).
For grins I just whipped up this spreadsheet....prices and performance may vary slightly but I think the general point I am making would still be intact.
Manifold.............Avg Retail $$...........Typical Gain.........Cost/HP
Stk FAST 78.............700........................8....... ............. $87
Stk FAST 90 (w/ TB)..1200......................13................. ...$92
FAST 78 w/ 85 mm.....900.......................11............... .....$82
Ported FAST 78.........1200......................18........... .........$67
Ported FAST 90/90.....1700......................23............... .....$74
The key is to understand that the snout doesn't represent the largest restriction in the FAST hence the smaller gains when messing with it. Reshaping and reconfiguring the ports are where the larger gains in airflow and power can be unlocked....
Tony
If you already have a good epoxied and ported 78 mm TB (like a Mark Shaner piece or something similar) score a 78 unit cheap and just consider having it ported. Even at the prices I charge to do a very neat and thorough job your return on investment is still better than buying a larger 85 mm TB and cutting up the snout which might close the gap in half between the 78 and the 90 netting you 2-3 HP. For an extra few hundred you would see an additional gain of 10 RWHP and a similar bump in TQ (my ported FAST 78 set-up went 20 RWHP and 15 RWTQ stronger than my former LS6/78 set-up as I previously mentioned).
For grins I just whipped up this spreadsheet....prices and performance may vary slightly but I think the general point I am making would still be intact.
Manifold.............Avg Retail $$...........Typical Gain.........Cost/HP
Stk FAST 78.............700........................8....... ............. $87
Stk FAST 90 (w/ TB)..1200......................13................. ...$92
FAST 78 w/ 85 mm.....900.......................11............... .....$82
Ported FAST 78.........1200......................18........... .........$67
Ported FAST 90/90.....1700......................23............... .....$74
The key is to understand that the snout doesn't represent the largest restriction in the FAST hence the smaller gains when messing with it. Reshaping and reconfiguring the ports are where the larger gains in airflow and power can be unlocked....
Tony
Last edited by Tony Mamo @ AFR; Mar 15, 2007 at 11:28 AM.
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Thread Starter
Joined: Apr 2006
Posts: 3,910
Likes: 1,158
From: Grand Rapids, Michigan
If I was buying new, I would get a 90/90, hands down. However, a lot of people don't think a 78MM FAST is worth that much (seen them for $450 on eBay, compared to $600+ for a 90MM). That in itself makes buying a used 78MM well worth it. I got mine even cheaper. After selling the ported TB that was on it, I only have $35 into the 85MM TB and $400 into the intake. You can't go wrong for that kind of money.
Originally Posted by Tony Mamo @ AFR
Consider this in your search for "value" (I look at everything on a HP per dollar basis).
If you already have a good epoxied and ported 78 mm TB (like a Mark Shaner piece or something similar) score a 78 unit cheap and just consider having it ported. Even at the prices I charge to do a very neat and thorough job your return on investment is still better than buying a larger 85 mm TB and cutting up the snout which might close the gap in half between the 78 and the 90 netting you 2-3 HP. For an extra few hundred you would see an additional gain of 10 RWHP and a similar bump in TQ (my ported FAST 78 set-up went 20 RWHP and 15 RWTQ stronger than my former LS6/78 set-up as I previously mentioned).
For grins I just whipped up this spreadsheet....prices and performance may vary slightly but I think the general point I am making would still be intact.
Manifold.............Avg Retail $$...........Typical Gain.........Cost/HP
Stk FAST 78.............700........................8....... ............. $87
Stk FAST 90 (w/ TB)..1200......................13................. ...$92
FAST 78 w/ 85 mm.....900.......................11............... .....$82
Ported FAST 78.........1200......................18........... .........$67
Ported FAST 90/90.....1700......................23............... .....$74
The key is to understand that the snout doesn't represent the largest restriction in the FAST hence the smaller gains when messing with it. Reshaping and reconfiguring the ports are where the larger gains in airflow and power can be unlocked....
Tony
If you already have a good epoxied and ported 78 mm TB (like a Mark Shaner piece or something similar) score a 78 unit cheap and just consider having it ported. Even at the prices I charge to do a very neat and thorough job your return on investment is still better than buying a larger 85 mm TB and cutting up the snout which might close the gap in half between the 78 and the 90 netting you 2-3 HP. For an extra few hundred you would see an additional gain of 10 RWHP and a similar bump in TQ (my ported FAST 78 set-up went 20 RWHP and 15 RWTQ stronger than my former LS6/78 set-up as I previously mentioned).
For grins I just whipped up this spreadsheet....prices and performance may vary slightly but I think the general point I am making would still be intact.
Manifold.............Avg Retail $$...........Typical Gain.........Cost/HP
Stk FAST 78.............700........................8....... ............. $87
Stk FAST 90 (w/ TB)..1200......................13................. ...$92
FAST 78 w/ 85 mm.....900.......................11............... .....$82
Ported FAST 78.........1200......................18........... .........$67
Ported FAST 90/90.....1700......................23............... .....$74
The key is to understand that the snout doesn't represent the largest restriction in the FAST hence the smaller gains when messing with it. Reshaping and reconfiguring the ports are where the larger gains in airflow and power can be unlocked....
Tony
Originally Posted by Tony Mamo @ AFR
Consider this in your search for "value" (I look at everything on a HP per dollar basis).
If you already have a good epoxied and ported 78 mm TB (like a Mark Shaner piece or something similar) score a 78 unit cheap and just consider having it ported. Even at the prices I charge to do a very neat and thorough job your return on investment is still better than buying a larger 85 mm TB and cutting up the snout which might close the gap in half between the 78 and the 90 netting you 2-3 HP. For an extra few hundred you would see an additional gain of 10 RWHP and a similar bump in TQ (my ported FAST 78 set-up went 20 RWHP and 15 RWTQ stronger than my former LS6/78 set-up as I previously mentioned).
For grins I just whipped up this spreadsheet....prices and performance may vary slightly but I think the general point I am making would still be intact.
Manifold.............Avg Retail $$...........Typical Gain.........Cost/HP
Stk FAST 78.............700........................8....... ............. $87
Stk FAST 90 (w/ TB)..1200......................13................. ...$92
FAST 78 w/ 85 mm.....900.......................11............... .....$82
Ported FAST 78.........1200......................18........... .........$67
Ported FAST 90/90.....1700......................23............... .....$74
The key is to understand that the snout doesn't represent the largest restriction in the FAST hence the smaller gains when messing with it. Reshaping and reconfiguring the ports are where the larger gains in airflow and power can be unlocked....
Tony
If you already have a good epoxied and ported 78 mm TB (like a Mark Shaner piece or something similar) score a 78 unit cheap and just consider having it ported. Even at the prices I charge to do a very neat and thorough job your return on investment is still better than buying a larger 85 mm TB and cutting up the snout which might close the gap in half between the 78 and the 90 netting you 2-3 HP. For an extra few hundred you would see an additional gain of 10 RWHP and a similar bump in TQ (my ported FAST 78 set-up went 20 RWHP and 15 RWTQ stronger than my former LS6/78 set-up as I previously mentioned).
For grins I just whipped up this spreadsheet....prices and performance may vary slightly but I think the general point I am making would still be intact.
Manifold.............Avg Retail $$...........Typical Gain.........Cost/HP
Stk FAST 78.............700........................8....... ............. $87
Stk FAST 90 (w/ TB)..1200......................13................. ...$92
FAST 78 w/ 85 mm.....900.......................11............... .....$82
Ported FAST 78.........1200......................18........... .........$67
Ported FAST 90/90.....1700......................23............... .....$74
The key is to understand that the snout doesn't represent the largest restriction in the FAST hence the smaller gains when messing with it. Reshaping and reconfiguring the ports are where the larger gains in airflow and power can be unlocked....
Tony
Tech Resident
Joined: Jan 2006
Posts: 5,117
Likes: 3
From: Philly
thanks for the info, Tony. you learn something new every day. thanks for teaching me something 
i'm really shocked that FAST charges hundreds more for the same manifold with a 12mm larger opening. i figured there'd be differences in the volume of the manifold or the size of the runners. this means the 90mm is theoretically cheaper to produce due to less material 
wow.
i'm really shocked that FAST charges hundreds more for the same manifold with a 12mm larger opening. i figured there'd be differences in the volume of the manifold or the size of the runners. this means the 90mm is theoretically cheaper to produce due to less material wow. Guys...
PM me for any specifics concerning your porting needs but you can pretty much figure my pricing from the math. I think I may have more R&D invested in tweaking these FAST intakes than the manufacturer themselves IMO. Your paying for my execution which is top notch, the R&D time I have invested to provide you with the results, and the consistancy/repeatability of those results proven time and time again with many independent sources....the best type of validation. The work I do is very extensive (and time consuming as it is all done by hand personally). Do a search and look for comments from the people I have helped....
That said lets move foward because I'm not wanting to hijack this thread....I think LS1Formulation's "resourcefullness" was very good and so lets keep things on track here. I did feel the info I provided was on topic (talking about value and how much power the $$$ buys) and worthy of consideration. As I said....I evaluate mods and their cost effectiveness every day of the week and what I tried to provide you with was a quick rundown and perhaps a slightly different angle or perspective.
And yes....the 90 mm FAST is certainly somewhat of a profit center for Comp but that type of situation is more commonplace than you think in the industry. The bottom line is you usually pay more for additional power and in that respect the cost is somewhat justified.
(Think about a CNC ported pair of BBC Pro Stock style heads such as a Dart Big Chief etc......the castings might have an additional $200 worth of aluminum but the cost can triple what a set of standard style BBC heads go for with similar hardware).
Regards,
Tony
PM me for any specifics concerning your porting needs but you can pretty much figure my pricing from the math. I think I may have more R&D invested in tweaking these FAST intakes than the manufacturer themselves IMO. Your paying for my execution which is top notch, the R&D time I have invested to provide you with the results, and the consistancy/repeatability of those results proven time and time again with many independent sources....the best type of validation. The work I do is very extensive (and time consuming as it is all done by hand personally). Do a search and look for comments from the people I have helped....
That said lets move foward because I'm not wanting to hijack this thread....I think LS1Formulation's "resourcefullness" was very good and so lets keep things on track here. I did feel the info I provided was on topic (talking about value and how much power the $$$ buys) and worthy of consideration. As I said....I evaluate mods and their cost effectiveness every day of the week and what I tried to provide you with was a quick rundown and perhaps a slightly different angle or perspective.
And yes....the 90 mm FAST is certainly somewhat of a profit center for Comp but that type of situation is more commonplace than you think in the industry. The bottom line is you usually pay more for additional power and in that respect the cost is somewhat justified.
(Think about a CNC ported pair of BBC Pro Stock style heads such as a Dart Big Chief etc......the castings might have an additional $200 worth of aluminum but the cost can triple what a set of standard style BBC heads go for with similar hardware).
Regards,
Tony
Last edited by Tony Mamo @ AFR; Mar 15, 2007 at 12:48 PM.
Originally Posted by lastcall190
Hmmm never realized the ported 78 combo gave those kinds of gains, all I heard was "get an LS6 the 78 is a joke compared to the 90". Good info...
-J
-J
Originally Posted by Tony Mamo @ AFR
Yep....welcome to the Internet....where accurate information is scarce and in-accurate information is plentiful.
Everyone has or had an 8 second daily driver too. 
Originally Posted by LS1Formulation
If I was buying new, I would get a 90/90, hands down. However, a lot of people don't think a 78MM FAST is worth that much (seen them for $450 on eBay, compared to $600+ for a 90MM). That in itself makes buying a used 78MM well worth it. I got mine even cheaper. After selling the ported TB that was on it, I only have $35 into the 85MM TB and $400 into the intake. You can't go wrong for that kind of money.
This is a good thread.