I just bought my L about a month ago and when asked, the previous owner said it was all stock. My factory boost gauge shoots up over 10 and looks like it would register about 12 if it were on the gauge. I finally got around to measuring the lower pulley today and it measured 8-3/4" to the outside of the rim. Upper measured 3-3/16" rim to rim. I believe I read that the stock lower is 7-3/4", so it's obviously been changed. Is this the 4# or 2# size? I've been running it pretty hard and have not noticed any detonation at all, so maybe he had a tune also. At this point my only mods are Bassani catback, K&N drop in with a ram air duct cut into the bottom of the stock airbox, boost bypass mod and pvc elimination mod with breathers. I know I should get a tune as soon as I can, but is it safe to run this way in the meantime? Was also thinking I need to go ahead and get a 160 Tstat too. What do you guys think? Thanks for the help.

 

Take a flashlight and examine the port on the ECM
up on the passenger side ... against the firewall. If
it has a chip in it you already have a tune.

 

i have a 2000L and all i have is chip and intake.... but when im at WOT and it's relatively cold outside(mind u I live in southern cali so cold is like 50-60 degrees) my boost gauge goes past the 10 psi mark to just past 11 i think.

 

Could not see any evidence of a chip. It may be a month or so before I can get in for a tune. Will I need a chip burned or would a tuner have a Predator or similar tuner he could connect and make changes that way?

 

Nonsense. First, I see an indicated 11 PSIG or more and I have a stock engine with just a JLP airbox.

Second, even if you have a 4 pound pulley, a tune is not required by any means. In all likelihood, it is far more "safe" to run a 4 lb pulley with the stock tune -- which Ford spent millions developing -- than with somebody else's tune. If you are nervous, take it to a dyno and have them check your air-fuel.

 

I put a 4# pulley on my truck with the stock tune (no chip) and my a/f ratio was low 13:1. Borderline if you ask me since it was 60 degrees out that day. Get into lower temps and things could go wrong.

 

edited for stupidity.. but anything out of the 11's is dangerous on pump gas... definitely get that thing on a dyno and check the a/f

 

What does the pulley look like? (any color, polished?)

Left to Right- 4lb caged, 2lb cageless, stock caged

 

I guess it looks most like the first one in your picture, except the six hex bolts seem to be on a larger raduis and there is no large center nut visible, if it's there it is recessed and out of sight. It is all black with no other color. After looking at it more closely, I think it is an interchangable setup where just the ring that the belt rides in can be changed to different sizing by just removing the six hex bolts. I'm sure it's a common make, but I don't know.

 

chesster51

You'll be ok as is. (assuming a stock tune) The 4# lower pulley is'nt as *explosive* as seems to be the popular opinion round bout here.

I would'nt flog it hard til you do know for sure what you have. But a few times here and there on 93+ octane won't hurt anything.



btw: got hp & birdy111 I won't show my A/F ratios.. but you'd look like this if you saw them. And yet?..... my plugs look like this:


Rich

 

I will add my 3 cents. I ran a 4 lb pulley and an airaid on a stock 02 tune for 35k with no problems. The next owner has flogged the **** out of it for the last 8 months with no trouble. That's on 91 octane. For your own peace of mind , take it to the dyno as many have suggested. Just my 3 cents..

 

I'm running 93 octane and will get to a dyno in the next few weeks. Since plugs have been introduced to this thread, should I change them also? I have 12,500 on the stockers, but if I get a "hotter" tune, should I go to a different plug? I know these are a bitch to change so I would want a long lasting plug so I would only have to change them every 25,000 or so. I've read a lot on here about plug selection and there are a lot of different opinions as whether or not iridiums are worth it. Do they last longer? Thanks guys.

 

Anybody?

 

Take a look at your stock plugs. If they look fine just keep using them. They are actually a very good plug.

Rich

 

hopefully you don't discover you already have a VIN locked hand held programer tune on your truck for that pulley.......