Holley jet area chart

Would anyone here have a Holley jet chart that shows jet sq" area that they could post up? Just playin with some numbers trying to figure what pvcr's to add to pri side with pri main jet to equal sec main jet area fuel. Thanks

It is hard to do with Holley jets since the jet size isn't the same as the hole size. So with Holley jets you first have to figure out the hole size and then find the area.

I think the easiest way to do it is look at the conversion charts that BLP or MaxJet have. I just switched over to BLP jets since the size is the same as the number. That makes it a lot easier to compare area. You just compare the square of the number.

This may give you a start. I think Thumper posted this up but I'm not sure.

Sorry guys, been alittle busy. Ok, i have an old Barry Grand book that lists all pin and sq in sizes for each jet, doesnt look accurate to what im finding on the web. Also, im reading that jet area in pri+pvcr needs to be 10-15% greater than sec side.Thanks

Yes, i agree. Using the jet flow chart im currently at 25% more flow on the pri with pvcr and main jet combined over the secondary jet. According some posts iv seen on racingfuelsystems some suggest 10% over secondary jetting to as much as 25% more on pri to compensate for lost flow thru the pcvr channels. Anyone know how accurate that is with a dominator? My current jetting is 82/90 with 75pcvr 1100 dominator on a 511. My wideband shows 12.5@wot in 45* weather. Im sure that will be too fat in 80* weather.

Experiment with the AFR at WOT to get the best results for your motor in your car
Don't forget that the butt dyno may or may not give you the best results Time slips don't lie

The little bit of testing that I've done shows that PVCR area is not the same as main jet area. It will get you close but then you need to adjust from there. I haven't done enough testing to know if it depends on the main body or the metering block.

Absolutely Cab. My question is would the front 4 cylinders run richer than the rear with richer jetting in the primary or would all cylinders get the same mix?

Getting the fuel distribution equal to each cylinder with a single plane intake and single carb. can be done but it usually isn't easy or even the same jetting for motors with identical or similar parts, DANG IT anyways
The AFR will get you close, checking and adjusting off of each spark plug will get you dead on
Tune off of #7 spark plug to start with if you have the stock firing order
Good luck, now get to work

Glad to see someone could use my list. Was going to look for it, and saw it already posted. Thank you P-burg!

Dave, I've got a sheet from Holley. They don't go by area but rather by flow. For example, a #80 flows from 690.0 CC's minumum to 717.0 CC's Max with a mean flow of 703.0 CC's. They are flowed using mineral spirits in CC's per minute. I don't know at what pressure, or or vacuum drop they use.
I called Holley back in July 02 and they sent me this sheet. Dave

Sorry I couldn't remember who posted that but I figured it was worth saving.

Yur right. #7 is always dark with the other end cylinders burning tan and center plugs burning white. I installed a wilson 4 hole tapered on my indy 4500 intake and the 4 leaf clover pattern is right in the air stream. Since i already have the porting tools ill just open that plenum up myself and save the $600 i would have spent with Wilsons.

Hey thats for that info, but according to Andy flow values are not accurate with pvcr jets because of the restrictive circuit its in, so not sure how to figure pri+pvcr jetting. I have an old Barry Grant carb book that has all the charts, but not sure if their still current.

This gets ya close.........square jet for ideal afr's and plug readings at wfo then drop down the primary jets 6-8 for now and see where that puts the wfo readings then size the pvcr's accordingly..........let's not confuse things more than needed...........

Hey, right now on the street it runs fantastic, but when those 80* temps come back around ill need to make some more tweaks and im thinking pvcr tune up. Dom, what size pcvr did you say you were using if ya dont mind?

I'm at .073 pvcr's with .084-.092 jetting and a 6.5 p/v. If it cruises nice on the primary jets you have then size the pvcr's to obtain the same afr's as when it was square jetted at wfo. If not, size the pvcr's/jets up or down to achieve what you need...........The bleeds will be easier to tune than jetting once you establish the needed jetting and will change the "curve" to fine tune to different changing conditions along w/the mixture screws...........

Yes, cruises nice now in 45-50* weather with 82 pri 76pvcr and 67iab. I also had to go back to the 39ifr to clean things up. Went back to the 26 emulsions as well. Wot 12.5 in cold weather, i will tune pvcr accordingly when the warmer weather comes back. May have to knock the 90 sec down to 88 as well. Seems odd how i have more cubic inch and bigger carb than you but it requires less fuel than your combo. Recalibrated o2 as well just to be sure. Not sure what to think about that.

Bigger motor pulls harder on the boosters requiring less fuel..........Boils down to give it what it wants BUT, et's and plug reading are the REAL deal and the afr's are what they are accordingly........

Ok, I can agree with that.