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slowpoke
11-02-2009, 06:24 PM
i have a 10% od on the sc atm. about to install a duel ic aswell and yes i have an ic fan. im looking for another 5% from a js pulley but looks like i can only find a 10% for the price im willing to pay. my question is will it hurt anything or will i be ok if i step up to 20% od? i have stock tb and maf with 3inch after market cold air intake (3inch maf housing ), very open easy flowing exhaust(2 1/4 pipes from manifolds into 1 3inch with a 3 inch stainless steel glasspack for noise, into 2 2.5's with 2 flowmaster 409's. 32lbs injectors, raised sc top, ic fan, currently 10% sc od. im pretty certain if any at all its not going to be much help since i have the stock tb and maf, i just want to make sure im not going to hurt anything?

Melon
11-02-2009, 06:52 PM
Out of curiousity - what's your price range? I think it's kind of weird that 10%JS pulley instead of a 5%.

Also, it sounds like the money could be better spent else where - fuel pump or injector upgrade, MAF, maybe TB, or maybe a tune. But that's just my thought.

-Melon

90blkbrd
11-02-2009, 10:42 PM
What do you have for blower and plenum?

The stock 94-95 plenum won't flow more air than what a 94-95 ported blower at 10% will put out.

slowpoke
11-03-2009, 01:29 AM
i have the m90 1990 blower, i got on the phone with bill from scp aswell, he says that the sc is only able to handle 15% without a bigger tb/maf and some head work. so it looks like 15% is going to be my limit. the fuel pump has been upgraded and as it stands the injectors are enough for now. yet if i add another 5% to get my 15% im thinking the injectors, tb and maf might be a must. and its had a tune already. im almost thinking to maybe upgrade a few small things instead. like the coil, get the duel ic done, do some pretty stuff, and just start to collect off to the side everything i need to do a real upgrade later down the road. as is stands from what ive gathered today im pretty much as far as i can get without doing some big upgrades across the board.

a second thought im starting to have to is i have a stock rebuilt sc 3.8, everything is there but the sc. that might be a better route to just start putting on upgraded parts on that and later on once this motor is shot then ill have a fully built motor to put in. im sorta at a cross roads of which way to go here. opinions would be very much appreciated in this mater. :)

slowpoke
11-03-2009, 01:33 AM
Out of curiousity - what's your price range? I think it's kind of weird that 10%JS pulley instead of a 5%.

Also, it sounds like the money could be better spent else where - fuel pump or injector upgrade, MAF, maybe TB, or maybe a tune. But that's just my thought.

-Melon

$115 for a used 10% js od seems a lil high since a new 1 is only $135. and thats the only used pulley ive seen lately. if im going to pay that much its not going to be for a used pulley. ill spread my butt cheaks a lil more and just spend the extra $20 and the 5% is $129

90blkbrd
11-03-2009, 07:35 AM
i have the m90 1990 blower

So an unported 1990 M90. IMO (and experience) You shouldn't be running more than 5%. Yes, at 10% the car feels like it's got more power off the line, but I can assure you just a few seconds later the computer is pulling timing and by the end of the 1/4 you have LESS power than you would have if you were running 5%.

I did some testing at the track on a 50 degree day with 5% and 10% overdrive. The first 1/8 was better and the 2nd 1/8 was worse for an overall equal time. My car ran identical 1/4 with 5 and 10% OD with a stock unported 1990 blower.

90blkbrd
11-03-2009, 07:36 AM
$115 for a used 10% js od seems a lil high since a new 1 is only $135.

I've sold 2 used JS pullies between $110-120, this seems to be the norm.

slowpoke
11-03-2009, 04:54 PM
So an unported 1990 M90. IMO (and experience) You shouldn't be running more than 5%. Yes, at 10% the car feels like it's got more power off the line, but I can assure you just a few seconds later the computer is pulling timing and by the end of the 1/4 you have LESS power than you would have if you were running 5%.

I did some testing at the track on a 50 degree day with 5% and 10% overdrive. The first 1/8 was better and the 2nd 1/8 was worse for an overall equal time. My car ran identical 1/4 with 5 and 10% OD with a stock unported 1990 blower.

btw, what all is involved with porting these out, i have 2 of them on the shelves, 1 is rebuilt. is this something i can do with my trusty dremal ? in such case does anyone have any pics so i can have something to go off of?

90blkbrd
11-03-2009, 05:10 PM
is this something i can do with my trusty dremal ? in such case does anyone have any pics so i can have something to go off of?

This is a decision you'll have to make and there are plenty of pictures and how to's if you search for them. But be careful, there are plenty of "I ported the blower myself" threads where they did it wrong. Making the V bigger isn't always better.