Most guys are running 8lb+ around here but I doubt that they run them full out all day at the track like I do.


Been noticing that short and long blocks are selling well these days...

What a strategy! You sell a cheap little pulley and soon after you sell the "mucho expensivo" long block.

TB

 

Hey, all I did was provide data. The data speaks for itself.

In theory, one simply keeps raising the boost until the power falls off. More boost = more density. More heat = less density. Ignoring mechanical efficiency, when the effects of the added heat outweigh the effects of the added boost, power will drop off because of a net loss in density.

But that assumes detonation control. And that assumption does not hold on pump gas. Almost without exception, every blown engine here has been from detonation.

Does a 6 lb make more power? Some say yes, some say no. Each camp has provided supporting data. But that extra power, assuming that it exists, comes at the expense of safety. A 6 lb is much more likely to detonate than a 4 lb.

So it really all depends on whether you can afford to risk a blown engine.

The "under the curve argument" is sound. I have suggested lowering the rev limits and shift points to maximize area under the curve without spinning the SC too fast on the top end. I don't think that anyone has tried this.

 

Without an exact # of RPM's my shifts were lowered, I will say that I think this was done on my truck when dyno tuned. It's evident where the HP drops off on any dyno graph so the shift should match that point. I know that a full dyno run should generate the max heat out of the heaton. While a quarter mile is WOT longer than a dyno run, the shifts would aleviate some heat each time.

I do know two things on my truck.

1. It shifted at lower RPM's after the dynotune with the 6#
2. I've realed in 4# trucks (slowly) that had more hp adding mods (efan, TB, water pump, etc = about 15 more RWHP) because I had 40 ftlbs torque on them.
3. The only reason I had to catch them was because of a truck headstart with slicks. I was on F1's= chitty 60's.

I have a feeling that if it went up to 5500 rpms before shift, this wouldn't be the case. No scientific data here though, so it's not the best.

I would think that on an autocross truck, the heat would be more detrimental.

BD

 

Gov, My L is also Dyno tuned by Paul and I have a REM ported Eaton, 4lb lower and 2.8 upper . I am happy with the results from Paul at REM.

 

HEY FAST GATOR...........I was simply giving him my OPINION. You say to everyone here, "Let him believe whatever he wants". I don't talk trash and lie to people here. My brother has definately beaten L's with 6lb pulleys. Not once, but twice. And each of those times their owners were surprised to learn that our truck had the 4lb pulley. I wasn't saying that this would be the same for him. I was just telling him of my personal experiences. The truck runs 12.80 @106 on F1's in the hot south Florida heat every time. Just because you like the 6lb better dosen't make me a liar.

 

Ask a question ... get 100 answers. I agree with FastGator. I went up from stock to 4lb to 6lb to adding a 1lb upper. Got better RWHP numbers with each. But, with that in mind, I did add an AFCO Heatexchanger also and got an awesome dyno tune (worth it's weight in gold).

Florida heat is a killer!!!

 

Gator is the man.. Been threw this with a friend of mine, trucks ran unbelievable close times... Had about 15 passes with him stock, then we modded and I went to a 4, he went to a 6, and he had me by 2 ten's every time.. We always went to the same track togather, so temperature and track condition were equal.. Now thats the bottom line ,,,, say no more...

PEacE...................
Jim

 

wydopnthrlt went to Paul at REM.. and he has a very fast truck for a 4#.

(I've ran against him and have yet to beat him) Soon to change though

 

Well WideOpen03SVT is my brother and im the one that has a 4lb and i beat 2 trucks that had 6lb pulleys and they had other little stuff over me also....And if i had to do it again, i would go with the 4lb......

BTW Fastgator isnt the man....

 

I say 4# max with the stock exhaust manifolds. With headers, the boost drops and the heat isn't as much of a problem anymore. Larger pulleys are then an option for more power with less chance for damage... With a good tune, of course.

 

Ok ... Ok... so whats that mean? I have beat 4 pounders when I was stock, Just cause you have beaten people with 6 lbs pulleys does not mean that the heat has slowed there trucks...

Gator is the man, he's got all the girls.. lol..

 

Sorry blown93, didnt mean to make a little joke about your boy friend...

And i never said anything about heat

 

AW ***** !!!!! I knew they were goin out. Blown93 and Not So FAST GATOR need to start fully reading peoples' replies. We are just stating our OPINIONS here guys. If you FULLY read my reply, you'll see that I put "IMO" befrore my answer. That stands for In My OPINION!!!! And Sinister's reply says nothing about heat Blown93. You guys need to pay more attention before you type.

 

HEY WIDEOPEN03SVT

So whats your frigging point?

THAT MY OPINION

Believe what you want, thats your choice

Btw I went 12.8 with a 4lber and a 11.90 with a 6lber in cool weather and a 12.1 in the heat.
So yes, a 6lb truck runs faster than a 4lb truck...IF you know how to deal with the heat from over spinning the Eaton.
Stick around, you might learn something

 

Relax jr

So you ran 2 trucks that had 6 lb pulleys and you beat them. So thatr makes it gospel?
Did it ever occur to you that maybe the trucks weren't tuned for the extra boost?
But since you say it, I guess I'll go outside and remove the 6lb off my truck and put a 4lb on, because you say it will be faster