Hi all, I just thought I'd post my dyno numbers from this morning. I added a #6 lower pulley friday night. While the numbers are impressive, they are not what I was expecting. I was looking for more, maybe I am just expecting too much.

The reason I was hoping for more is that my truck did something like 381HP/455ftlbs on just a chip and drop in panel airfilter alone! I figured that two pullies and a power cooler would add more numbers?

I should also say that my truck ran only a 13.20 with the above mentioned chip and filter, while it has run 12.40's with my current mods (with the exception of the #6 lower which like I said, I just put on last night). I just would have thought that it would have taken more than 23HP and 50ft/lbs to change from a 13.20 to a 12.40(or lower hopefully now with the #6).

later,
chris

P.S. again, i'm not disspleased, it's just that the more I think about it I can't believe that I gained only 20HP from two pullies (extra 7 or 8lbs of boost) and a power cooler and an open element filter??? I guess the strip will tell the tale next spring

 

chris you are a spoiled brat,

 

I dynoed my 01 this past July in the heat of South Ga. Had a 3lb. pulley, JDM warm weather chip, th/body, and JL RamAir. See sig for numbers. Plan to do another one this winter with updated mods.

Dan

 

TTT

 

Don't be comncerned with "peak numbers", those don't win races. Compare the two curves and you'll see that you probably have ALOT more low-end and midrange power than before. You could also have a very safe program. Tuning will really make power, but it comes at some expense, like engine life.

 

excellent point, I'll have to compare the before and after graphs and check that out. thanks.

later,
chris

 

I see some great numbers there. I'm glad my #6 will be here in a day or 2 along with some Denso's. I don't have the upper yet but if you come around me you know its on the way. But I think the the #6 six should help since I'm only running alittle #4 on my truck now. LOL J/K There are goin be some serious runners on F1's this year coming.

Tommy

 

CornerCarver's right. Spinning the blower that fast is going to kill it's efficiency at the top end. Your biggest gains are going to be in the mid RPM ranges, where the blower is still efficient.

I can't wait to see what happens when those rotors self-destruct from the high RPM's that those pulleys are creating.

 

The sky is falling...the sky is falling!

I remember once upon a time (only about 6 months ago) when everyone said that 2lb lower pullies were the most you could safely use, and that anything more would just create more heat and no additional power (JDM). Obviously this has not proven to be the case. and while I do understand that there has to be a limit to blower speed, it has not been found (YET ) How many rotor melt downs have you seen?

Oh and if/when it fails, I guess what'll happen is that I'll order a new one.

Merry Christmas everyone!

later,
chris

 

Chris,
My thoughts exactly!!!

Matt

 

Did you have a wideband O2 hooked up? If so, what was the a/f ratio?

 

no, they have one and I have made some recordings with it on previous runs back in the summer, but I forgot to ask them to use it this time. I obviously did send the chip back for a reburn to work with the new upper and lower pullies.

I should have checked the A/F this time but honestly, I completely forgot about it until you just mentioned it.

later,
chris

 

I recently pulled 400.0rwhp and 483ft./lbs. My mods include long tube headers #2 pulley; Billet T/B; chip and filter. I added the two pound pulley; billet T/B and new program and got 17-18 rwhp.

Sometimes 2+2 does not equal 4. Checked my A/F and they were at 12.7 at peak HP. Need a little more fuel for my tastes.
Check your A/F's and don't be to dissapointed, those are some really good numbers.

 

I have dynoed the 2# pulley and the 4# pulley against the stock lower pulley and there was a gain of 16HP and 48ft.pounds of torque with the 4# pulley over stock BUT everyone is missing the point,on the dyno this 4# pulley was making 30-36HP more from 3100-4000 rpms then it narrows to only 16 HP for the total end result which is very misleading to how much these pullies do help our truck.I have a 6# pulley coming for christmas so i will have it dynoed against my 4# to see the differences between those 2!

Matt

 

At the rate everyone is modding....high 11's to low 12's will be about average this season.Who would have thought.