I have a hundred and fifty bucks to spend, I was thinking about getting the perrin i/c hoses or a vishnu or perrin pully. Anyone ?

 

i doubt you will fell any difference if you go with the ic hoses... a perrin crank pulley is supposed to do a big difference over the stock one..

 

I have Samco intercooler hoses and I didn't notice one bit of an increase. There many be a little more up top but I couldn't tell you. They look nice. I have a Perrin pulley (not installed yet) and from what i've heard you will notice a difference. 5lbs compared to 1lbs? Numbers wise that should make one hell of a difference.

Todd

 

The pulley will make a bigger difference as you engine will rev a lot quicker ..... if you are interest I have a Vishnu Pulley for sale .... PM me if you are interested ...

 

Some say that a lightend crank pulley is not good for your engine since the stock pulley also acts as a harmonic balancer.

 

There have been posts regarding the harmonic balancer and one that I saw had an quote from SOA stating that the WRX does not have a harmonic balancer. So changing out your pulley can't take away what wasn't there in the first place.

 

I have seen that also but I have also read some arguements that possibly discredit that quote.

quote:
Originally posted by AZScoobie
1. Why do the Stock pulleys have drill marks on them? Ever looked? The pulley is mounted to the crank and it is spun balanced and drilled.

2. If you look at 5 pulleys why do they all have drill marks in slightly different spots?

3. Why do higher RPM STI engines have a heavier pulley along with a Center rubber dampener?

4. Why do some light weight pullies cause real bad spark scatter at the high rpm and cause misfire codes?

Clark
http://forums.nasioc.com/forums/sho...114#post6071114


Quote:
Originally posted by AZScoobie
I have seen many pullies cause Spark scatter which causes detonation and misfire. Mainly around 6500 rpm. I reported this to Vishnu when this occured on my own car. Vishnu knew of the problem and suggested I remove it. I did. I would say that many motors have died from pullies.. High rpm detonation due to spark scatter is bad news.

Cya

Clark
http://forums.nasioc.com/forums/sho...114#post6071114


Quote:
Originally posted by keyd
Has anyone with a 'suspect' aftermarket pulley or flywheel sent it to a shop with a CNC dynamic balancer to have the balance verified? Is it balanced to within .02 oz at 9000 rpm? Different shops/machines have different levels of balance/tolerances.

A crankshaft with only two ounce-inches of imbalance at 2,000 rpm will be subjected to a force of 14.2 lbs. At 4,000 rpm, the force grows to 56.8 lbs. Double the speed again to 8,000 rpm and the force becomes 227.2 lbs.
http://forums.nasioc.com/forums/sho...114#post6071114


I dont know if a lightend crank pulley is bad for our engines or not and I must say that there are more people are happy with them then people that are not. I thought it might be a good idea to bring this up so people can do their own searches and make their own decision on whether the slight performance increase is worth the possible risk.

 

i had a perrin on my car but took it off. my car did rev a lil' faster. but the fact that it doesn't have any type of dampner on it i took it off. if you read about the perrin c/p it will tell you that it doesn't have a dampner and it may shorten the life of the engine. but i also read in the first issue of subie sport that the wrx motors don't really need one.

 

ill sell u a brand new perrin pulley for 95 shipped. never installed.

 

thanks for the indepth reply. now i know not to get the pulley.

 

The I/C hoses were my first upgrade, they gave me about 5 hp (g-tech). I'm still debating the pulley.
The hoses let the boost come on a little sooner, not much though.