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So, I received a free fast 78/78 combo from a guy who obviously didn't need it. I've been sitting on it a while, but would really like to get them installed, but......
As you can see there are 3 bolt holes that are damaged, 1 that is cracked.
Am I still able to use it or will I have ridiculous problems?
I have a 2001 trans am, so I suppose I have the LS6 intake, but would really like install this intake and TB setup to go along with my 85mm MAF and new lid.
May just need to replace the top shell. I wouldnt run it like that without at least trying to repair it
I would prefer not to invest too much into a 78 setup, if I did I suppose I would have to call up fast to see if their current top shells are compatible with the 78 lower. Regardless, I need to contact them to get the correct bolts for installation. I was reading about a guy who fixed his broken bolt hole with a piece of aluminum tube and washer. I might consider that.
The 78 lower is only compatiable with a FAST 90 top shell and yes I would for sure fix those broken tabs before you put it on or go the route that you just mentioned. You just need to make sure it is clamped the whole way around.
The 78 lower is only compatiable with a FAST 90 top shell and yes I would for sure fix those broken tabs before you put it on or go the route that you just mentioned. You just need to make sure it is clamped the whole way around.
No the fast 78, 90, and 92 all share the same internals the 102 is different the only thing that changed were the top shells. Op find 92 top shell by calling fast or someone it will fit on the 78 intake then just get new gaskets. fixing that top shell is a losing battle
Oh man. I'm confused now. I just got off the phone with fast. Talked to a guy named Steve, who said they don't sell the installation bolts for the 78 and told me the 92 shell isn't compatible with the 78 lower. He could be wrong on both. Maybe someone with some experience with this could chime in?
fast customer service is about the most useless thing on earth fwiw lol.
He put me on hold for what seemed like 2 pretty simple questions and his answers weren't that convincing. If someone has done either I would love to hear it, so I can put this thing on
The 78mm, 90mm, and 92mm upper shells all use the same lower. You can put a 90mm or 92mm on it no problem. The 78mm will accept a stock or stock replacement throttle body, while the 90mm and 92mm will require an aftermarket 4 bolt throttle body.
You won't gain anything from a FAST 78mm swap over the stock LS6 intake unless you have internal engine work, and even then it won't be much. Not worth the ~$450 cost of a new upper shell IMO. However lots of people don't install the button head valley cover bolts and crack the lower shell so there is a demand for lowers. You may want to put the lower up for sale.
I personally have a fast 78 and have personally tried putting a 92 on top and it does not fit. As well as numerous people have tried. The bottom shells are different
I personally have a fast 78 and have personally tried putting a 92 on top and it does not fit. As well as numerous people have tried. The bottom shells are different
Thank you sir. Do you have any idea if the 92 and 78 bolts that mount the intake to the engine are compatible?
Having owned one... The 78/90 top shells are interchangeable. The 92 is NOT at all. Good luck finding a 90 top shell
use the GM bolts. They're fine. Get the low-pro button bolts for the valley.
If you decide you don't want it, sell it to me, lol
Getting advice from someone with real life experience holds a lot of weight, so thank you for that.
The fact that you want it makes me feel like it still might be worth something lol.
Gonna be ordering the bolts I need soon. I might just order a set to replace the gm bolts, so I can use them as a guide as I repair the fast while the ls6 intake is still on the car. I already have someone hounding me to get my ls6 intake lol.
Getting advice from someone with real life experience holds a lot of weight, so thank you for that. The fact that you want it makes me feel like it still might be worth something lol. Gonna be ordering the bolts I need soon. I might just order a set to replace the gm bolts, so I can use them as a guide as I repair the fast while the ls6 intake is still on the car. I already have someone hounding me to get my ls6 intake lol.
Perfect then. Free intake, AND you come out ahead!
If would HIGHLY recommend ordering the new rope gasket for the inside though, that seals the top shell to the bottom.
You'll just need scissors, the rope gasket, and some RTV Ultra Black.
Take the top shell off and you'll see what I mean.
10-28-2014, 12:09 AM
Free Fast 78/78. Can I use it? 
