Glad to hear you've got a good solution to the cracking issue. I've tried some [plastic repair] two part epoxies from specialty shops and the results are similar. They work... for a while. I now only use them as secondary sealant.

For what it's worth, I have a welder and have found it does not work on the FAST bottom manifold. I had one come in from a local shop with a big crack across the bottom plane. It looked like it was tightened down on the old style (pre LS6) water crossover piping. In any case, I welded it back up and it cracked again within 10 minutes of use on the engine. The intake bottom was more warped then any I had previously seen and this may have been a factor. The FAST is truly a "space age" polymer and the bottom at least is not worth welding.

 

I bought my first FAST for my car used and it didnt come with the button bolts for the valley panel. I used JB weld back then for the bottom panel when I ported the C5's throttle body. It takes forever to set up but never broke again once it was repaired. That FAST is still in service today on a C5 Z06 and never cracked again.

The cracks were small such as seen on the one above. It was a permanant fix and was fine when removed it 3 years after its fix when I sold it.

 

When I said epoxies I should have specified "plastic-type epoxies" not to be confused with JB weld. Sorry if I confused anyone.

 

But did you have to wear that speedo the whole time???? And let's leave birthdays out of this, OK?

 

Good research, Spin, and superlative customer support !

I used the PC7 epoxy (which I have used on many of my diesel truck parts) but also used three-point mechanical reinforcement:


1. The bolt that holds the manifold together at the back corner
2. The buttress of epoxy behind the bolt tunnel on the passenger side
3. A machine screw with the nut EPOXIED on, (and coated with epoxy inside) on the driver side

PC7 is rated to only 200F, but I believe that is sufficient for intake manifold duty, where the actual stresses are quite low, particularly with the three-point mechanical restraint. I would use the JB Weld if I were to do this again; Spin has proved its superiority for this application.



The instructions for PC7 indicated to mix one part gray with two parts black for a more flexible joint, which would be a good idea for the FAST modification.

 

well i dont have your intake but if i did i would be pleased in the lenghth you have went to fix it....good job

 

I too used a 2 part epoxy like pc/7 (my HD didn't have pc/7 in stock) and let it dry for about 24 hours, it was hard as a rock when done. The car ran great for the week I had it after I fixed it...so well I blew my diff to smithereens. Matter of fact I set a new racing PB with my newly repaired intake before I blew the rear. That FAST just works.

In my case I think the vast amounts of oil in my intake fouled the goop, I don't think it was heat, I noticed that I can put my hand on the intake at all times, it just doesn't really get that hot. My goop felt like rubber cement and seemed impregnated with oil, and peeled off like rubber cement. I suspect Spin may have gotten a bad batch of goop. I have since scored a Cartek catch can, and no way oil is going to get in there past that. Thanks again to my dear buddy Craigster. A true gentleman.

I have been silent on this issue thus far, and feel the need to speak. EVERY manufacturer/vendor/business will have problems from time to time and may turn out a bad product. My business does from time to time and I focus on those errors to make sure they don't happen again. It's how someone handles the problems that separates the good guys from the rest. IMHO the way Spin is handling this warranty issue is the way things should be handled. Top shelf service. Though I would expect no less from the mighty Spin, it's always a nice reminder that all of humanity is not lost when you see people doing the right thing.

Thanks again for my FAST Spin. It is a great mod. (Second only to my beloved cutouts)

 

That 05 diff gave you over 300 passes and owes you nothing. I'm surprised it lasted a day at the track.

 

I'm not complaining, it gave good service and a lot of 1.5's.

I have a Cartek adaptor on it's way to put a c5 diff in my car. I hope the 3 mounting points of the adapted c5 prove stronger than the c6 design.

 

Did I look better in the velvet red or the lavender vinyl?

 

Spin is a righteous dude--period. He doesnt have to go to the gym, he is solid in many other ways.

 

You of all people know the importance of balance, proportion, and symmetry in building your body. Now there you had to go make my head bigger....now I have to get the arms up .22% with calves, and quads 1.3 times that.....it never ends. Thanks a lot.

Its been 1 year and two weeks since the surgery and I have to say, the funniest thing happened on incline dumbell presses yesterday.....the dead left arm got one more rep with the 150 lb'ers than my right arm. It was my left that went dead last year prompting the spinal surgery. Who would have thought the left would be stronger one day? I have no doubt that I will one day be that big again but if it doesnt progress from here, I'm fine with it all. Static strength peaks in your mid to late 40's and most lifters get their best lifts in the early 50's. While I'm giving up the heavy stuff (no more 500 bench presses), that doesnt mean I cant hit it as a workout poundage for reps. I'm at 405 for 10 so I know its gonna happen. Lifting for looks works faster with lighter weights. Its just that what you think is heavy becomes light.

I so lucked out, but then again, things always seem to work out for me.

I love God....no bullet could have stopped me.
I love Dr. Victor Smirnov for being the guy that could get all 16 fragmented parts of that bullet out.
I love the doctors at Western Nassau Ortho for putting me back together.
I love all those friends that took me to the docs when I couldnt.
I love sushi.

 

UPDATE: When the JB Weld is cured enough to hold its shape (not dripping anymore but still pliable), you must bolt/TQ the top cover to the bottom cover to let it fully cure in the position it will be in when the cover is stressed and bolted in place. It can crack if it cures and you have to then put huge pressure to bolt it down. No epoxy, including this one is going to be elastic for long into the curing process.

It didnt actually happen to me but Cory Harris mentioned that his attempts with fixing plastic manifolds suggested that it should cure in its stressed condition of being used.

Makes sense.

 

Another outstanding thread, guy. I was beginning to miss your contributions
Also nice to put a face to the name... Man you're huge... I wouldn't want to mess with you

I have a quick question... Have any of these FAST manifolds you put together been used under boost? I keep hearing from different tuners that using a FAST on a boosted car can lead to it splitting apart... Figure the FAST is about 8 inches wide by 14 inches long, with a curved top; the surface area is probably somewhere over 120 square inches... At 10PSI that's half a ton pushing it apart

 

I love dim sum. Tastes best when served in Hong Kong.

 

Nah...you know that trick with a fresh steak to make a guard dog happy???

Very true, in the past few months, I am at 345 for 8 reps, which is a record for me, and I turn 50 next week.......AAAGGHHH SAVE ME!!!!

(Is this where I put the obligatory pic in???? )

You are a lesson for many....and pardon me for saying what you may not have wanted to...

For those who didn't know, Guy was shot and died, and was brought back a few times on the way to the hospital. Many others who would have been so fortunate, would be living narcissisticly since feeling their mortality. Instead, Guy spends his life giving back to others as payment for the Lord sending him back and giving him another chance. If he makes any money in the process, he gives it to help children get the same 2nd chance he was given, and spends whatever time he has left over involved in his local church making it a better place for those in need.

Whether you agree with his technical oratory or not, his conviction to the good of others is something we all need to emulate to make the world a better place.

Dribble off, down off soap box...

 

If that were true the MAP sensors would be pushed out. Its 10psi just like an air compressor hose makes and the manifold has been in boost situations the best example I can think of is MrBig's car with great success. 760rwhp and the MAP doesnt even get pushed out with not even a clip to hold it in.

10psi isnt breaking the airbridges apart and they are far weaker than the manifold. With the TB open the same pressure is everywhere in the intake tract evenly.

I dont know why you think the internal volume of a manifold should be used in multiplying the effect of boost pressure. Its 10psi.....thats it.

Thanks for the kind words...all.

 

Erm, guy, the MAP has a 0.3inch diameter nipple... A = PiR^2, so the area of that MAP is less than 0.1 inches squared. At 10PSI there is less than 1 pound of force pushing it out. Not a very good example
On the other hand, the 8 x 14" manifold has a surface area of over 100 square inches... Remember; PSI = Pounds Per Square Inch... The bigger the area the more force.
Mr. Big is the main reason I want to try a FAST, I just wanted to know if you knew of anyone else running one under pressure...

 

I like the idea of using glue/epoxy as an air-tight sealant and mechanical means to secure the plastic patch piece. Nobody can argue with the JB Weld tests. However, over time with stress, engine vibration and heat cycles on different materials with different thermal expansion charactoristics, it could fail. I personally would feel better with a couple of mechanical fastners.

I personally am not in favor of epoxy a nut inside the manifold. If it ever comes loose, it could get sucked into a cylinder. There are many types of blind mechanical fastners such as speed nuts, threaded inserts which can be pressed into the manifold plastic, and pop rivits.

Just tossing out a few ideas.

 

Amazing