No 2.5" pulleys available on a fast check, but I sourced a 2.6" pulley and installed it today:

Drove it a few miles and saw 4-6 psi boost pressure... never needed or had an opportunity to want more...... this truck is now OFFICIALLY and CERTIFIABLY QUICK!!!! <img src="/forums/images/graemlins/scared.gif" alt="" /><img src="/forums/images/graemlins/kewl.gif" alt="" /> Great Googamooga!!! <img src="/forums/images/graemlins/scared.gif" alt="" /> <img src="/forums/images/graemlins/scared.gif" alt="" /> <img src="/forums/images/graemlins/kewl.gif" alt="" /> <img src="/forums/images/graemlins/kewl.gif" alt="" />

I haven't had a chance to get it on the highway and wind out any gear - probably haven't turned more than 4000 rpms in any gear yet - but I don't know why anyone would need any more power in this truck.... it seems like a'plenty.... but.... I'll probably try a smaller pulley after the bugs are ironed out.... guess I'm now a converted boosthead. <img src="/forums/images/graemlins/lol.gif" alt="" />

There's a lean flat spot on hard acceleration - then it goes stoichiometric - then it goes rich (as it should).... need to play with the regulator and find out what satisfies the transition through boost... more pressure - more/less zero boost fuel pressure rise - and/or more/less rate-of-pressure gain.

The transmission is still not right and before I do anything else, I need to get some gauges on it.... tried loosening the cable, but it still shifts too smoothly and is slipping a little (I think).

The serpentine belt side load is too much for the old stock tensioner/idler pulleys. The adjuster pulley side load is high and wear in the OE pulley allows a wobble - which causes the belt to ride out toward the nose of the idler - which then causes the belt to ride up on the lip of the fan pulley - eventually shredding the belt. For now, I have it under control, but need to use better pulleys. I found these MOTOBLUE GenX pulleys with double bearings (replaceable bearings):

They should have enough front-to-rear bore length to stop the wobbles, but I'll have to rework the tensioner bracket assembly to provide the needed stud/bolt length and diameter.

I'm not there yet, but getting closer. <img src="/forums/images/graemlins/kewl.gif" alt="" />

Frank

Wow that is awesome. I want one. Glad to see you got it finished. I cant wait to ride in it. Did you put the oil cooler on yet? I need to stop by again and talk, listen and learn.

No, the oil cooler isn't yet installed - but it will be when I get the kinks worked out of everything. Come on down when you can - it'll get better when it's fully tuned, but you'll like it as is! First order of business now is the transmission - before I burn it up.

Frank

Awesome Frank! Come on down to Atlanta, not sure on the pricing but I know where there's a nice AWD dyno that normally is used by the Evo and WRX crowd. I'm sure everyone would love to see the numbers a boosted Raider puts down! I can't wait to see AWD burnout pics too <img src="/forums/images/graemlins/smile.gif" alt="" />

Haha, David - I probably need a 2.2" pulley and ~10 psi to do that with these 32x10.50s.... I might get there in time, if my hatchet doesn't break. <img src="/forums/images/graemlins/smile.gif" alt="" />

Frank

Once you are hooked on boost there is no know cure. The worst part is every year you need just a little bit moe to stay happy.

When my Blue Raider got hit and totaled seven years ago I swore off building another one.. I would go cold turky on the pressurized intake Raider.

After about three months I broke down and started building another, yea I'm hooked.

Sounds like you have made some amazing progress, keep at it!

Kevin

Lord, please oh please don't let Frank's 'hatchet' break! <img src="/forums/images/graemlins/smile.gif" alt="" />

Yep - I can see why....... it's addicting. I built several fast cars long ago - all carbureted - but have never built... or even driven..... a supercharged one - except for turbo-diesel cars and boats. The turbos I understand and appreciate, but the blowers are a different breed of cat entirely. With the turbo, you get boost once the revs build... even with part throttle.... with the positive displacement blower and a bypass valve, you get nothing until you dump the manifold vacuum and ask for power.... so, you have a mild-mannered engine that seems completely stock until you push the go pedal enough to open the bypass valve and then all Hell breaks loose. <img src="/forums/images/graemlins/evil.gif" alt="" /> <img src="/forums/images/graemlins/evil.gif" alt="" /> While both force-feeds require pedal modulation, the Roots transition is completely linear in feel - but certainly not in sound. It's extremely hard to keep my foot off the floor. <img src="/forums/images/graemlins/notooth.gif" alt="" /> <img src="/forums/images/graemlins/oink.gif" alt="" />

If/when I drop down another pulley diameter, this thing is gonna be nasty. <img src="/forums/images/graemlins/evil.gif" alt="" /> <img src="/forums/images/graemlins/evil.gif" alt="" /> <img src="/forums/images/graemlins/kewl.gif" alt="" />

Frank

To me the net effect is the same.... Better HP with a very mild motor with a lot more low end than a cammed up motor.

There is a differance in feel as the turbo has that windup feel as it spools up, for me thats the best part.

I feel the down side of a turbo is a bit " over blown" <img src="/forums/images/graemlins/smile.gif" alt="" />


Kevin

Probably so - I wasn't criticizing turbos - just describing the difference in pedal modulation timing. So far, I'd say a turbo is easier to drive because it's rpm controlled where the blower is manifold vacuum dependant and comes online in a hurry.... but I'm not yet adjusted to it.

Frank