For those with a KB or anyone else, what would you suggest I use for a lower pulley? I ordered a KB and want to know what the safest combo would be on a stock block. Thanks

 

Which upper pulley does it have? Mine shipped with a 3.25" upper (I was told it would have a 3.5") and with a 4# lower and full exhaust it's making 17 psi right before the upshift. KB claims it's only 15 psi or so. Too much in my opinion for a stock block so I have a 3.5" upper going on.

Jody

 

ub2slo- i have a KB on my truck..with the standard 3.5'' pulley on top..and a 4lb lower on the bottom...i make 15lbs on my stock block...and no problems so far!! about to put a full exhaust on..and ive heard it drops the boost a pound

 

5300 miles, 9" (6 lb) lower, 3.20" (2lb) upper, dynatech longtubes, 16lbs of boost over 60degrees, 18lbs of boost anything colder than 60 degrees. Not one problem with my L, mind you I do have a very conservative tune. 496/562 at rear, 12.1 a/f, 5200 shift point, 93 octane - best run so far 12.2 @ 111 - like I said very conservative tune - that's the key regardless of the boost you are playing with.

D-Day

 

I'm considering using your setup, is yours a daily driver? Great #'s by the way

 

She had her first day yesterday as a daily driver. I just sold my other F150.

I am very very pleased with my set up. I have just about every mod you can get except juice an alcohol injection. She runs like a champ for the street. When I get a little more serious on the track I will be installing a 2400 stall converter to keep my safe tune and get into the 11's.

Good Luck with yours!

D-Day

 

I still don't get why mine makes more boost than anyone else I've seen for the pulley combo. With the 3.25" upper and 4# lower I make 17 psi on a 80 degree day. With the same pulleys as you I would make 18-19 psi above 60 degrees where you only make 16. I have the LT on there now too.

My other comment is that I would have thought that with those numbers you'd be running 11.70's or so. I've seen several guys claim 11's with about 50 less hp and less torque than you. Are those times on street tires or slicks?

Jody

 

Well, I have heard that sometimes rotar packs can have installation differences, as in packed with less clearance than others creating more or less boost, but that is hear-say.

As far as my time, I can't stress enough that I have a very conservative tune and my tuner plays it really safe below 3000 rpm which as you know is one of our strengths.

I had Johnny, from JLP look at my file in Bradenton when I did the 12.2 - his comments were - I have two choices, get aggressive with my tune or get a 2400 stall. I hurt in my 60ft's, best yet 1.77 so with that being said I will get the stall because I want to stay with the conservative tune. And I was using 28x16x10 hoosiers.

I hope that sheds some light on the subject.

D-Day

There is another thought, some pulley's claim a certain lb gain, but are actualy larger in dimension, thus producing higher boost gains.

 

Thanks Dan. I am certainly not knocking your truck at all! My goal for my 03 is the same. I just thought if I was in the 475 rwhp range I'd be in the 11's with slicks. I do have alcohol/water injection which allows more timing under boost, but doesn't help out of boost where a race tune would be adding more timing down low also to get the truck moving. I am also penalized with 91 octane here.

I want to be solidly in the 11's without having to run a race tune. Maybe the rotor thing explains the boost difference, cause nothing else makes sense; I'm making 2-3 psi more boost than KB or anyone else says I should be making. I'm going to put the 3.5" upper on the truck today because 17 psi and stock block don't play well together!

Jody

 

camojb,
I see a solid 17#'s with a 8.5 lower and a 3.25 upper. I also have stepped long tubes with 3" high flow cats. It's a lively streets set up. But last week I burnt a plug and will now go with a 3.5 upper untill Danny can add a little more fuel.

NoSurprise

 

I have a 10"(JLP 8lb) lower and 3.5" KB upper and I see @17# normally. I have full exhaust as well.

 

I forgot to add, I am only running on 14 degrees timing. I am sure that plays into the equation.



D-Day

 

ANy of you KB guys know of any used ones for sale?? or a Works??

Thanks
Matt

 

3" upper 8.5 lower=19 # and 15 degrees at 5200 rpm on 91 octane, 12.1@114 on the street side with slicks. I'm not saying it's a 11 second street truck.................................... yet.

NoSurprise

 

You're the first guys that have boost numbers like mine....good to know as KB quote 2-3 pounds less for those same combo's, and that's with the stock exhaust which will show more boost.

I was running 19 degrees of timing with 91 octane and alcohol injection, but I quickly chickened out and cut it back to 16 degrees and am running water instead of alcohol right now. The stock manifolds and mid pipes are going back on today until I can figure out a way to quiet this thing down.

Jody