pulleys

[N2TRUX]

Originally posted by WatchThis
Hey Ken - I know a 4lb pulley is safe to go with on our trucks, but you think we might get away with the JLP 5lb pulley and a set od IT20s without adding a chip and be okay? Interesting. I have not thought about that. You think the plugs will take care of any more detonation becuase of more boost? Of course doing the wide band dyno check and make sure everythings was okay. Just wondering. Of course I would talk to JL before trying such a thing, but I don't want to ask him a dumb question...
David

I can save you the trouble of asking JL about the 5# pulley. Here is what he told me-

From: JlightningRacing@cs.com Save Address
Date: Thu, 16 Jan 2003 08:32:46 EST
Subject: Re: 5# pulley
To: abcmusic@mail.ev1.net

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you would need a *custom* chip to run a 5#,we reccomend the denso's it 22's.....JL

And here is a thread, with links that may help you decide what you think is right-
http://www.f150online.com/forums/sho...hreadid=103705

[grayhd2]

ken,

The micro tuner does change shift points..... makes them a little crisper/harder.

[ken800]

Originally posted by N2TRUX
I can save you the trouble of asking JL about the 5# pulley. Here is what he told me-

From: JlightningRacing@cs.com Save Address
Date: Thu, 16 Jan 2003 08:32:46 EST
Subject: Re: 5# pulley
To: abcmusic@mail.ev1.net

--------------------------------------------------------------------------------
you would need a *custom* chip to run a 5#,we reccomend the denso's it 22's.....JL

And here is a thread, with links that may help you decide what you think is right-
http://www.f150online.com/forums/sho...hreadid=103705

Ok, now let me illustrate why my thoughts are different than JL. Granted, he has been doing this a while, but...

The IT-22 is 2 plug ranges colder than stock. IT-20 is 1 range colder. Go to PSP's web page and you will find they recommend the IT-20 for up to 4lbs and an IT22 for over 4. If you search f150 online, you will find similar beliefs from "groupthink". From simple math, 4lbs on an L is like a 7lb lower on a HD and A 5lb on a HD is less than a 3lb on the L which a lot of L owners would run stock plugs on... I don't doubt JL believes he is correct, and I don't doubt sal believes he is correct. However, someone is not... who is it? How do we know? The answer is: WE DON'T.

I'll say it one more time. Someone give me a 5lb lower and pay for the time on the dyno and I'll run it just to prove a point. At the end of the day, I might be wrong, but in this case, after have looked at the calculations of blower rpm and such, I feel like I'm correct also. Someone is wrong here obviously... Who is it?

Keep in mind that lower pullies are sold to the HD community as 2lbs less than the HD. If you read my pulley calc. thread, I and a couple of others provided the first numerical proof that this is NOT the case and that pullies and associated tuning for the HD need to be sold per what they do to the Harley and not relative to the L... No tuner has stepped up yet and I don't know when they will. (with 25,000 of these on the street by the end of this year, someone will, I assure you) My thread on the pulley calculations goes one step further in that not only does the HD not net 2lbs less on any given pulley, it also doesn't net the same increase in actual increased airflow because of those ratio differences.

So what I am saying is a set of pullies, 2, 4, 6 etc. must be manufactured and marketed specific to the harley upper. This would end all of the "relative to the L" confusion... The sizes would be different than the L for all pullies...

Everyone keeps telling me to swap the upper with an L and then I'm cool... I don't want to... I don't believe in changing a pressed on pulley that was put on with a 20,000PSI press by using a pulley puller and then relying on tightening the nut to repress it on... Just my opinion as MANY have done it and I haven't heard of any blower failure at the shaft bearing...

Go back and read the pulley calc. thread on f150 and feel free to comment. I'm always ready to be proven completely wrong and will admit it.

http://www.f150online.com/forums/sho...5&pagenumber=1

In God I trust. All others I verify.

Ken

[Blackhawk]

As to performance increase, my 4# and properly tuned chip netted 1 second lower ET and about 5 MPH in the 1/4. Running high 13's and feeling safe.

[WatchThis]

Hey Ken - I went and read through your post on the pulleys. I was following it for a while, but then I shipped out of the country and I have lost track. Anyway, after looking at your chart of the different pulleys on the HD compared to the Lightning, I have a couple of questions/points. The 5# pulley is only turning the HD blower 14135 RPM and the 6# is showing 14538 RPM. The 2# pulley on the L is turning the blower 13976 RPM and the 3# is turning 14639 RPM. This is showing that a 5# pulley on our trucks is going to turn less blower RPM than a 3# pulley on an L. Now is the L is able to run a 4#, blower RPM = 15230, pulley without a chip then why couldn't you run your 'custom' pulley without a chip since it runs the same RPM as a 4# pulley on an L? The ratio of the two pulleys together is the key here. The tuners are going to say don't do this or do that because they might think that the pulleys are a straight across 2# difference on an HD than an L. Well thats not the case since the upper pulley size is different, then once you change the lower pulley that ratio changes. I wonder if any of the tuners have sat down and run the numbers? If your math is correct you could run a 6# pulley on our trucks with no chip since it to turns less RPM than a 4# on an L. Am I missing something here? There has to be a catch. I was thinking about the MAF and the amount of air being sucked through it, but it boils down to the fact that the RPM of the blower is what pulls air through the MAF. I am trying to find the loop hole, and I can't find it. Do you have any light to shed? There must be something wrong with me thinking.....

[ken800]

You guys are now following the same line of thought that I am...

No, there is no catch.

I provided the formulas in this or another thread for you to double check my numbers. Mmeyek did his independtly of mine and comes up with the same numbers.

I then used the "max potential boost" formula to solve for pulley size and it, too gave me the same answer.

Welcome to elightenment.

Yes, it is theortical that the custom pulley that I want made would be safe with no chip... That is assuming that the HD has the fuel tables mapped all the way to 5.0 volts. I have been told by someone inside ford that they ARE filled out at least as far as the L computer, if not a little farther... However, there is no way to get that data in writing. I don't want to START testing at that high of a boost level with no chip. I'll start on a 5lb and work up from there... but I don't have one and I'm not going to spend $225 just to get one...

If I had the time and the pulleys on hand, I would be willing to dyno/datalog a 2lb, 3lb, 4lb, 5lb, 6lb, (my custom), and an 8lb with no chip. Doing it in this fasion will tell me where I begin to cross the line, if ever... If the 4 was good, the 5 was good, the 6 was questionable, then I'd know I crossed the line at 5...

As I told someone else yesterday, though, I am worried that you guys think I am challenging the tuners to a knowledge contest and saying they don't know their biz. I am not and would probably never argue with a tuner in a public forum. If they say do X or do Y then they probably have some valid reasoning behind it. I just can't blindly follow recommendation, though, without knowing *why* or *how*. It isn't a question of their knowledge or ability to tune... It's my need to know the hard data behind the decisions.

Bombtech put a 6lb lower and a diablo tune by REM and ran a 13.3 @ 105 in the 1/4. That's better than I have ever run and he has less mods... I know Paul at REM knows his tuning and I know that his company provides phenomenal customer service.

However, that's not my point at all here and I don't want this to turn to vendor bashing... My point is that I would like to know how far out we can run our trucks without a chip... and what would the HP look like?

Ken

[GRY GHST]

Ken800,

I want to thank you for all the work that you are putting into getting hard data -vs- hearsay data. I am sure that Ford will not share with you any of the fuel table information for the Harley ECU. So the only alternative is to try to map it out with experimentation you have suggested. The data that you gather will not only be invaluable to the members of this board but also the tuners who may use it to fully optimize programs they write.

Thx