I would have thought boost pressure has nothing to do with the reliability of a supercharger. Isn't it the fact that to get the extra boost traditionally you're over revving the charger, and the teflon can't handle the centrifugal force and falls off?

 

In your application the larger volume of the supercharger, and the smaller the capacity of the engine, means you will develop higher boost levels than say a 1.6L GZE or a 1GGZE at a lower charger RPM.

 

I'd get that motor balanced with a big aftermarket pulley like that on the front too, bearings won't be happy about it at all.

Edited February 6, 200917 yr by beerhead

i think the teflon coatings start to peel off when there over reved due to the heat caused by it

 

any ways heaps cool should go good, what sort of mounts are you using? is it a just off the shelf sort of thing? or are they a custom jobbie

Edited February 6, 200917 yr by dbr11k

I would have thought the teflon melting problem was from too much boost as when you pressurise air it gets hotter and by 17psi it would be getting pretty hot!

heat combined with centrifigul forces, you get the pictue.

I would have thought boost pressure has nothing to do with the reliability of a supercharger. Isn't it the fact that to get the extra boost traditionally you're over revving the charger, and the teflon can't handle the centrifugal force and falls off?

 

The more boost your running the more pressure it has to build up. so more boost puts more strain on the supercharger. and as mentioned, the more boost you run the more you have to rev it, the more ti wears things out like seals and bearings.

yea i heard that sc14s don't like to much boost, i would keep it under 12psi, it will have enough to knock of your socks

hell yea, I'm only gonna be running 6-8psi. hope to have some fun on low boostage.

I don't see why boost alone would cause the teflon to fail. It would be heat + centrifugal force. If you keen on running high boost through the charger anyway maybe a good atomizing water spray before it?

Edited February 15, 200917 yr by Jason

check on this but i heard if you spin the sc12 or 14 superchargers too

fast it melts the teflon seals, i think about 12psi was some sort of limit...

nah bro we ran 16 through ours

it was fine with 16 went killer too.

don't knock stuff till you try,

believe me from from first in hand experience it works.

never go by what people say if they have never tried it.

And how long did it last?

 

Not like overboosting will kill it right away tho.

you should be able to run 12psi all day on a SC12 or SC14..

Both the SC12 and SC14 have rotors made from extruded ally and are hollow in the middle, with a wall thickness of about 3-4mm plus the Teflon coating, so if you spin them to fast the rotors grow and the Teflon on the ends of the rotors wear off against the side of the body.

 

I have been there done that 15,000 rpm on an 18RG motor.

 

With the high boost if you have the SC14 on a 1300 cc motor it works Ok. But the higher the boost the harder the SC has to work and the less efficient it works,

So it is a compromise. If the engine runs a half decent compression around 8 to 1 it will perform very well on low to mid range boost.

 

I have a 4k that has 1ggte rods, forged Honda pistons in it, comp is at 8.5.

It runs well on 7 psi, but needs 98oct fuel to stop it pinging

I have just stripped the motor down to rebuild it into new shell and found it pinged to much as all the ring lands on the pistons are broken. But motor is 6 years old and driven very hard.

Edited February 17, 200917 yr by Crostek

And how long did it last?

 

Not like overboosting will kill it right away tho.

 

IT STILL IS GOING!!!!!!

IT STILL IS GOING!!!!!!

 

OKAY!!!!