Plastic intake + a ton of boost?

[hotmustang331]

Well about this time next year, I plan on buying a forged SB and stg 2 HP TTs...and to keep costs down i will probably leave the heads and cams alone. I plan on sending around 18PSI though the engine with 8.5-1 CR, so my question is, will the stock plastic intake handle 18PSI? I dont want to get rid of it as I have a P&Ped upper plenum. If im not misstaken 5.0 mag ran like 16PSI through a stock intake testing the plenums, also made over 600HP. Plenum added around 20HP, so mine being hand P&Pd should give even more, and I really dont want to waste it and the time. Thanks

 

[DBMSTNG]

i wouldn't trust 18psi with the plastic intake. that may be pushing it a bit.

 

[AirWolf87]

i would go to an aluminum manifold. you can just bolt on the bullit's i think

 

[hotmustang331]

So you guys think it will crack then huh? You know what the limit is?

 

[300bhp/ton]

So you guys think it will crack then huh? You know what the limit is?

isn't this the joy of modified cars, esp on a route that not many people take, your car will be quite unique so the problems you encounter will also be unique.

No one on this site is really likely to know what will happen thats why comapnies spend $$$$$$$'s on R&D, even if the intake failed for 1 other person on this site it may have had nothing to do with the psi level or could have been caused by a combination of things (other mods, power level, turbos, plumbing, age of vehicle, how its driven, where they live (weather, temp, humidity levels), fuel grade, tune, etc, etc, etc).

All you can do is try it and see, basically do the R&D yourself, if it fails then try somehting else or if you're worried about it then change it first.

Have a look around at how other turbo applications esp from car manufactures and see what components they use as it may give you clue to what will work and what doesn't. Basically lean on the industires experiance and R&D.

 

[WRXracer]

I really dont see how the plastic intake would fail.. it is really strong..

 

[1992 2.3LX]

i think you will get a mixed response to this question. if you have the aluminium crossover you are better off. but i do believe there are some folks on MD that are running lots of boost 20+ psi on factory plastic. but i think it's a crap shoot. run it till she blows and save for a new intake while you run the plastic

 

[Kronos]

With that much boost you are taking a chance but you might as well wait till it cracks before you spend money on a new one. I would just keep an eye on it.

 

[99RioRedVert]

It will not crack or break. I don't know why people think this. Its not made out of paper. Its a very heavy gauge plastic and 18# of boost isn't that much force on the walls of the intake. There are tons of guys running high boost through these intakes with no problems.

These intakes have been cracking for other reasons. They usually crack at the coolant passage. The newer style intake with the aluminum coolant passages are superior, but this has nothing to do with boost.

 

[2001sleeper]

i agree, it won't crack

 

[WRXracer]

thats what im saying.. it wont crack..

 

[hotmustang331]

Coo, thanks a bunch guys...its funny how everyones opinions change or everyone agrees when someone makes a very confident statement LOL. I was worried but the intake seemed pretty tough...I also found like a MPH tuned car running 17.5PSI through a plastic stock intake, also made like 601 RWHP with stock heads and custom cams....centri setup. I have been thinking, I may just slap the TTs on the stock SB and run them at 8 psi until I drop a rod or something, or once i reach 100K (whichever comes first), no since wasting a good engine since im going to buy a new block anyways. Should still make around 500RWHP, thats plenty LOL. Its all up in the air, but i am DEFINATLY going with FI, and definatly sending 18PSI through it eventually. Thanks again.

 

[97v6Silver]

if your gonna be tearing down teh motor anyway why not just replace teh thing

 

[Mstg05]

I'll bet 10 bucks the rubber seals blow out before the manifold cracks...

 

[hotmustang331]

if your gonna be tearing down teh motor anyway why not just replace teh thing

I just cant make my self shell out 10K all about at once LOL. And on top of that, replacing a motor that will only have 40-50K on it by that time, as im going to buy a hole new SB. $6200 is enough to spend on my DD LOL, that I said "I wont mod this car, I already have a hot rod".

And to the above poster, I really dont doubt it LOL.

 

[VividDreams]

i think at those power levels though you will be really restricting the motor with the stock intake