I swapped the M90 parts onto my '95 Mustang and I'm wondering if I have a leak. Its all stock parts from a '91 SC, but with a FMIC (2.5" piping). It'll build 10psi, but that is peak and it doesn't seem to come on as quick as I would expect. I had a couple obvious leaks in the tubing which ended up being clamps that weren't tight enough. I installed the factory upper and lower IC tubes onto the SC hat and the manifold. I bought an upper gasket kit that came with a few round rubber gaskets. I figured thats where they went, but wasn't sure exactly how they went on and ended up forgetting about them. I've also read about the teflon gaskets that a few people sell, but I might go with the factory ones for now. Just need to know how to properly install these things to make sure its not leaking. Thanks!
Question about intercooler tubing gasket(s)
- Thread starter Jamez
- Start date
QuickMustang
Registered User
Your best bet to get a good seal is to run a small bead of black high temp RTV around the tubes before you tighten them up. If you have any other performance mods after the M90 like ported heads, exhaust work, etc. than 10 psi isn't too bad...I only build 9-10 psi with ported heads and a port matched intake...
nickleman60
Registered User
I've run the teflon gaskets on 2 of my sc's for years now without a problem, they're easy to install, no mess and reusable. Buy them and you won't regret it.
I was assuming stock psi was somewhere between 10-12 depending on the ambient temperature. I know the coupler is bad and I just got it running a couple weeks ago and there is already black powder/oil coming out from behind the pulley onto the spark plug wires. I know its not old dirt because the wires are brand new. I was hoping this wasn't a sign of some internal damage or something, but it will definately need attention. The risks of buying used parts 
Can you get the gaskets by piece or just a whole kit? I thought about RTV, but with the shapes of the parts, I didn't want to put a huge glob on only to realize I needed a thin bead around a certain area.
And a side note, anyone pay attention to intake temps with a stock M90? I use an xcal2 and LiveWire software. I logged not too long ago during a 95-100 degree day and the IAT said about 135 degrees after a WOT run to about 95mph. I imagine if I had gone longer it would've gone up a bit, but is that about right? I've seen some Cobra guys call their M112's Heatons so I figure these weren't much better.
Can you get the gaskets by piece or just a whole kit? I thought about RTV, but with the shapes of the parts, I didn't want to put a huge glob on only to realize I needed a thin bead around a certain area.
And a side note, anyone pay attention to intake temps with a stock M90? I use an xcal2 and LiveWire software. I logged not too long ago during a 95-100 degree day and the IAT said about 135 degrees after a WOT run to about 95mph. I imagine if I had gone longer it would've gone up a bit, but is that about right? I've seen some Cobra guys call their M112's Heatons so I figure these weren't much better.
Mike8675309
Registered User
... there is already black powder/oil coming out from behind the pulley onto the spark plug wires. I know its not old dirt because the wires are brand new. I was hoping this wasn't a sign of some internal damage or something, but it will definately need attention. The risks of buying used parts
The seal behind the snout pulley is what is leaking the fluid. The power you see is rubber coming off the belt when it slips on the pulley. Make sure you keep an eye on the fluid level in the blower crank case.
The round gaskets (o-rings) you had are for inside the ends of the intake tubes. They rarely need to be replaced, and to get to them you need to back a collar.
Look at how the tubes fit together when you assemble. How to apply the RTV should be apparent.
Jim Demmitt Jr
Banned
Only way to seal
I ran tefflon IC gaskets the RTV or Ford tape sealer is junk under high boost levels you can make your own by going to a Plastic store. Here in Calif we have Dapp Plastics get a mall sheet of tefflon cut your own you can re use them over and over
Last edited:
rickbtbird
Registered User
don't waste your money on the gaskets just get some RVT
I heard of several type of gasket material used for this application. I didn’t care for any of them except the Teflon Gaskets. It’s a little more expensive but so much easier and no clean up when you disassemble the IC pipes. Torque them to mid range of the 15-22 foot pound specification (or about 220 inch pounds). Bottom line is the joints can’t leak or you’ll have issues.
CurtisPaulfrey
Registered User
wrong, the black will not hold.........I found this out when Dave had my car on the dyno
you need to get "Ultra Copper" high temp TRV it comes in a gold tube.....
No its just a stock N/A Mustang motor with dual exhaust. I have a catted h-pipe and mufflers sitting in the garage. I'm still working with Justin at VMP to get the tune closer. I won't have my wideband going till I get the exhaust installed so it can only be "close" till then.
I love the torque this thing makes though. Its awesome being in OD and being able to pass without even unlocking the converter. I'm hoping this setup with stock blower parts will get me into the 13's with the non-motor mods I have. Ultimately I'd love to see 12.99 without tearing into the motor. I'll have to invest in some slicks and do some weight reduction in the near future
Ddubb
Registered User
Never heard of Dapp Plastics, do you mean TAP Plastics ?
The TAP Plastic in my area does not sell Teflon sheet, I had to go to Professional Plastics to get the right type of material.
- Dan
I got some PM's about gaskets so I'll order some of those and see how things go. About the supercharger, will a bad coupler damage anything else? The leaky seal will obviously need to be watched, but will that cause other damage assuming it doesn't run low or out of fluid?
I just got the thing running right the other day and the torque is insane. Turns out the coil pack was bad which made a significant difference in power. It will absolutely shred the tires through first and into second now. I read a lot about upgrading/replacing the SC and I'm not even sure if I should mess with repairing the '89-93 SC that I have from what everyone says about them. Might just keep fluid it in and let it go until I can find a '94-5, S-port, or something of that nature.
I just got the thing running right the other day and the torque is insane. Turns out the coil pack was bad which made a significant difference in power. It will absolutely shred the tires through first and into second now. I read a lot about upgrading/replacing the SC and I'm not even sure if I should mess with repairing the '89-93 SC that I have from what everyone says about them. Might just keep fluid it in and let it go until I can find a '94-5, S-port, or something of that nature.
CurtisPaulfrey
Registered User
12.9 is going to be hard with stock parts, but the mustang isn't as heavy as an SC
90blkbrd
Registered User
How do you know your coupler is bad? If the coupler does fail it could sheer off the pins.
If you go to a bearing store and purchase the seal for the snout, it will run you between $7 and $20 and the whole process to replace it will take less than an hour.
Paul from BTM (if anyone knows who/what that is) stopped by while I was in the middle of my build. He pointed out the slack/click when you spun the SC. It spins freely, but kind of caught for a sec and he said that was a bad coupler. I also get the "marbles in the SC" sound at idle. I'm learning about these things so although I know its not good, the thing still whines and builds boost.
The other thing is that before I put it all together I noticed one of the rotors had a dent in the leading edge. The opposing rotor didn't have any damage in the same spot so maybe the were removed at some point and got damaged outside of the case? Evidently it doesn't make that much of a difference, but all things considered it doesn't seem to be worth much in terms of performance or value.
The other thing is that before I put it all together I noticed one of the rotors had a dent in the leading edge. The opposing rotor didn't have any damage in the same spot so maybe the were removed at some point and got damaged outside of the case? Evidently it doesn't make that much of a difference, but all things considered it doesn't seem to be worth much in terms of performance or value.
As for the 12.9 thing, I'm thinking a list of parts simliar to this:
S-Port or better
Full Exhaust
10% OD
DR's or slicks
I'll have a MAC 2.5" catted h-pipe and a couple of flowpaths installed pretty soon. I already have 3.27's/tlok and a 2600 stall. The FMIC I got seems to be doing a good job, but these tires are nothing against the torque. They just give up in 1st and still cry mercy in 2nd
S-Port or better
Full Exhaust
10% OD
DR's or slicks
I'll have a MAC 2.5" catted h-pipe and a couple of flowpaths installed pretty soon. I already have 3.27's/tlok and a 2600 stall. The FMIC I got seems to be doing a good job, but these tires are nothing against the torque. They just give up in 1st and still cry mercy in 2nd