tonyb

I am gonna re post this in this section along with the external.

Has anyone had sealing issues with thier Fast 90mm base lining up with the AFR heads and leaking?Everyone with a Fast 90 complains about the throttle body sticking and I fixed that but the idle was still fluctuating.I went ahead and hooked the motor up to my evaporative system smoke machine and found a leak on the intake port of the #2 cylinder.I pulled the intake and was puzzled with the problem.The intake has locators on all cylinders except #2+7 and that is were mine is leaking.If you push the intake back when tightening it, the #7 leaks,If I pull it forward ,the #2 leaks.There is no happy ground here.I found the problem to be that the locator holes in the head on #2+#7 fall right under the intake seal on those cylinders when pulled back or forward on the intake.I don't know wheather the problem is the heads or the intake but I fixed it by filling the locator pockets on the head on #2+#7 with ultra gray sealant,installing the intake and letting the car sit 1 day and I re tested with the smoke machine and I have no leaks.The car now idles better and I feel more confident on not leaning out a cylinder and popping a motor.
Anyone else with this combo try using a smoke machine?Does anyone else have this issue?I worked on it for 7 hours before I even figured it out.Without the smoke machine there is no way of telling there was a leak.Any input would be great.
Anthony

goober35

iTrader: (1)

just a small stupid question. What where u TQ the intake down to.

tonyb

What they said.30 in/lbs first pass ,50 in/lbs second with a snap on torqometer.I tried everything and finally used a grease on the o-rings to leave match marks and did this about 15 times to try different scenerios and came up with the same problem every time on #2 or #7.

goober35

iTrader: (1)

Is that Fasts TQ specs the stock ones are 89in/lb

Tony Mamo @ AFR

iTrader: (13)

Any digital pics?

I have never had a problem and my intake has been on and off at least a few times...

Also, you did use the special low profile button head bolts in the valley tray right? If not the intake would certainly not tighten all the way down.

Keep us posted.

Tony M.

Also, did you re-use your old intake rubber gaskets? Perhaps they are flattened out to much and not getting the job done. I installed some new gaskets that FAST sells because I wasnt comfortable using my old ones from the stock intake.

tonyb

I used the button heads,I bought new o-rings when I found the leak originally.When AFR modified the locator bosses and enlarged them,did you enlarge all of them?The one boss on each head need not be done as there are no locators on the intake on that one boss.Is this the possible problem/solution.It is sealed so I am not taking it apart until the next problem or whatever so there are no pics.
Tony,can you pressurize yours with a machine and see for sure yours is not leaking?With what I see and can't imagine I am the only one with this problem with this combo. I believe most people don't have/use some technology to see this type of problem .If mine leaks again I will epoxy and fill the bosses on those cylinders that are causing the problem.After spending a total of about 15 hrs diagnosing and fixing the leak,I am not gonna take the intake off if not necessary.
Anthony

ChucksZ06

iTrader: (9)

I put a fast 90 intake and throttle body on my sons 02 camaro and the base was warped on cylinder one so much that it would not pull tight. It was also warped on #2 but not as bad. There was no interference any where. The curve in the sealing surface was obvious when you looked at it. We used some hi temp rtv and made the best of it as we had waited 2 months to get intake in the first place. The way the intake is constructed( compared to gm intake) the bolt bosses are not made to put pressure on sealing surfaces as well as stock intake does. I am going to have to use a fast intake on my 403 I am building in order to port match heads so I hope it is not warped.

tonyb

Yea,I was worried it was warped but that wasn't my problem.If mine was warped it would have been easier for me.
Anthony

Tony Mamo @ AFR

iTrader: (13)

I took a real close look at a FAST 90 intake thats brand new, out of the box, and has never been installed on a running engine. I was actually quite shocked how warped it was. I'm talking lay a straight edge parallel on one side of the intake and it misses the other side by 1/2 an inch (the intake is bowed up so it would "rock" if you placed it on the motor). Considering your having a difficult time to get either #2 or #7 to seal (opposite sides of the intake), the warping that I see could certainly cause that unless you crank down on those bolts pretty tight, essentially taking out the bow in the intake. I might try and take a digital pic of what I'm talking about if someone can host the photo for me.

Anyway....I believe its an issue with the intake not the heads. The heads are machined perfectly flat and there is plenty of aluminum around each port to seal up the rubber intake gaskets. Plus, if there was something wrong with machining of the heads, we would have received a tremendous amount of calls from our dealers and other customers. Obviously, there is always a small chance the CNC machines "hiccupped" or had some sort of a tooling issue when yours were being run, but the odds of a single isolated problem like that are very slim.

Hopefully your current fix gets the job done....

Thanks,
Tony

XLR8NSS

iTrader: (4)

Tony - Send me the pic if you get it, I'll host it for ya.

xlr8nss@hauln.net

tonyb

I compared the fast intake with the LS6 intake sitting on my floor and I do believe it is an intake problem.The stock LS6 intake has brass locators on #2 + #7 and the fast has none,this leads to the intake shifting and"warping" on those two cylinders and the problem is compounded by the AFR having opening up the locator pockets.I am gonna hook up the smoke machine on a regular basis until I feel comfortable with the fix.
Thanks Tony,I will keep you in the loop on how things go down the road.
Anthony

Tony Mamo @ AFR

iTrader: (13)

I think you are just looking for an excuse to keep playing with your smoke machine...

tonyb

Wellllll,Maybe! No,actually I feel like a test pilot on a failing mission with the GTO.Everything I do is a project that has not been done on these cars.The motor part is the easy stuff,The drivetrain has been expensive and very trial and error.
Anthony

Aaron's 00 TA

iTrader: (6)

A local STL guy had an issue with his FAST intkae being warped. It would not seal, similiar to what you are describing. He had idle issues and FAST told him to use sealant to fix it or send it back. He optioned to send it back, and they sent him a new one that worked fine. You would think that FAST could make a decent product for the price of what you pay.

ChucksZ06

iTrader: (9)

I think it sucks that we are paying 870 dollars for warped intakes. Fast needs to change the mold so the bolts will pull the outside corners of the intake flush with the heads...come on fast. Someone else will step up and you guys will lose a bunch of buisness. No complaints on the concept but maybe some r & d changes are in order.

leaftye

Chuck, it's hard as hell to make a mold for plastic parts that allows the completed part to be perfectly flat. Now when it becomes a very complex part, it takes a master mold builder. I can't fault them for having an occasional warped part, but I'd think it'd save them money to do a simple check before shipping the part off and having myriad problems and bad publicity down the road.

Mike Mercury

ding... ding... ding; we have a winner !!!

Squintz Palladoris

iTrader: (1)

I am sure FAST double and Triple checks all of their products before they would actually ship them to anybody.
Especially their Throttle Bodies.

ChucksZ06

iTrader: (9)

I know it is hard to make plastic parts thant do not warp. That is why I suggested a redesign of the outside mounting bosses so as to help pull the outside corners of the intake to the head surface. There are no excuses for shipping parts that are defective. I understand that the manifold being in individual pieces makes it much more suseptible to warping than with a all in one piece manifold. Kris is shipping me a 90 mm fast intake and I asked him to eyeball it before sending it.