what do you guys think about 2.80 upper and #6 lower? i have a custom port but its pretty much a stage 4.
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2.76 upper + 4lb Lower?
- Thread starter disasterpiece83
- Start date
Some of you guys are clueless. Bigger is not always better.
If your running a 2.8 upper then your most efficient combo and fastest 1/4 pass will be made with these combo's;
ported 2# lower
unported stock lower
Running any more boost then this will give you some low end torque yes, but unless you never shift past 4,000 rpm then what is the point.... Again, this has been proven over and over so stop trying to reinvent the wheel here.
If your running a 2.8 upper then your most efficient combo and fastest 1/4 pass will be made with these combo's;
ported 2# lower
unported stock lower
Running any more boost then this will give you some low end torque yes, but unless you never shift past 4,000 rpm then what is the point.... Again, this has been proven over and over so stop trying to reinvent the wheel here.
To much heat with that many lbs and not having it ported IMO, either that or spray it lol!
I have a few friends that run this setup but they have stage 5 ports they love it....
Do a 2.76 only and call it a day , the others combo will peak out at 4500 give or take, then after that it all hot air...
I run a 2.65 upper and I love it...I hope with a port it really runs good.
Not nessesarly true, i ran my 2.76/#4 and also 2.93/#4 same night and the 2.93 cost me an average of .1, swapped the 2.76 back on and got my .1 back. Thats all the proof i needed and i was running at the track regularly back when i did this test, no datalogs or anything just a wad of timeslips in my hand to prove the point. The car ran a best of 11.32 @ 122 with the unported 2.76/#4 pulley setup and would have gone faster with more seat time but i switched to the ported blower.
Just curious but what are your 1/4 numbers and setup? Your so adamant that more isnt better you must have some personal experience in the matter.
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Posi port, 2.76 & 2lb and I promise you its all you need, and if its not enough you can switch the lower ring to a 4lb. I had a 2.76 w/posi port and it was fast, slapped a 2lb gain 60tq and it was like putn a pulley all over again.
Try some E-85, wouldn't that keep the temperatures cooler or have I been misreading information?
IMO the 2.76 upper would go well with a 2lb lower at most, maybe going a touch or two bigger on the upper would make the eaton more efficient and not as hot. If you go with something on the upper in the 2.8/2.9 area a 4lb lower would be a better application.
IMO the 2.76 upper would go well with a 2lb lower at most, maybe going a touch or two bigger on the upper would make the eaton more efficient and not as hot. If you go with something on the upper in the 2.8/2.9 area a 4lb lower would be a better application.
I ran a 11.55 @ 120 with a 2.8 upper only on a nonported blower. When I put on the 2# lower I went 11.6x at 121. I now have a ported blower so I'm hoping for low 11's, high 10's.
That is just my personal experience, but if you look at the fastest Eaton list, you'll see the 2.93/4 and 2.8/2 combo's are the fastest. And that is all the proof I need. Just ask Jake
oke:
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That is just my personal experience, but if you look at the fastest Eaton list, you'll see the 2.93/4 and 2.8/2 combo's are the fastest. And that is all the proof I need. Just ask Jake
Lol, im on that list :rolling:
With longtubes it is not as much of a stretch to use the 4# lower over a 2# wtih a ported eaton. I'm guessing the OP does not have longtubes or a ported blower, so a lower is a waste of his time unless he plans on cooking food on top of his eaton.
Jake uses 2.93/6lb combo and it's a hair faster with it than the 4lb'er on it. I use a 2.9/6lb combo but will experience with a 2.9/4lb'er also. Then with an upper only after that more than likely.
Just to clarify.
Just to clarify.
I'm going to spend some time writing up a nice thread with my thoughts on all of this stuff soon.
Here's the easiest way to make a decision.
If you want as much power out of an Eaton and you're going to run with the car cool then pulley it for more. That way you'll have the same numbers at the track or even on the street as the dyno. If you expect to pulley it for a lot of boost say a 2.76/4lb lower and it dyno's 490/500 non ported with the car somewhat cooled down you'll hardly ever have that power on the street. So if you street race you're shooting yourself in the foot.
Now...
If you want the exact same hp on the street as the dyno anytime you want it then run less boost like an upper only or a mild upper lower combo. 2.76/2lb would be pretty aggressive but would still see close to the same hp as on the dyno.
I've been trying to think of a way to write this up for about a month and it's very hard to word as you can see here lol. People think that since they have a ported blower running a 2.76/4lb or a 2.9/6lb combo that it sees the same hp/tq on the street in everyday driving as it did on the dyno and most of the time the car doesn't because it's to hot and will pull timing. Sure maybe in 1st gear or 2nd gear but by the top of 3rd or 4th where races are won it's going to be pulling timing if the car is heat soaked.
So why not make it to where how the car was dyno'd that power is available anytime you want to floor it?
Here's the easiest way to make a decision.
If you want as much power out of an Eaton and you're going to run with the car cool then pulley it for more. That way you'll have the same numbers at the track or even on the street as the dyno. If you expect to pulley it for a lot of boost say a 2.76/4lb lower and it dyno's 490/500 non ported with the car somewhat cooled down you'll hardly ever have that power on the street. So if you street race you're shooting yourself in the foot.
Now...
If you want the exact same hp on the street as the dyno anytime you want it then run less boost like an upper only or a mild upper lower combo. 2.76/2lb would be pretty aggressive but would still see close to the same hp as on the dyno.
I've been trying to think of a way to write this up for about a month and it's very hard to word as you can see here lol. People think that since they have a ported blower running a 2.76/4lb or a 2.9/6lb combo that it sees the same hp/tq on the street in everyday driving as it did on the dyno and most of the time the car doesn't because it's to hot and will pull timing. Sure maybe in 1st gear or 2nd gear but by the top of 3rd or 4th where races are won it's going to be pulling timing if the car is heat soaked.
So why not make it to where how the car was dyno'd that power is available anytime you want to floor it?
Exactly what you told me when I called you, thats y I went with th 2lb lower and couldnt be happier, always running strong. I was tryn to say the same thing and if the OP wants to be able to drive for a while and not have to ice his blower down or be able to do repeated highway pulls then a 2.76/4lb is too much IMO of course. Oh ya and I wouldnt even think of go n this rout without a ported blower.
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^Exactly and I'm getting better at saying it on the phone than typing it up on here that's for sure.
You could run that 2.76/4lb combo on a ported blower on the street "if" you know when to crack on the car. That's not when you're sitting in traffic and get the first break in it to go full throttle. Cruise for a little bit and let the heat exchanger do its job and get some cooler fluid back under the blower to pull a little heat out and then crack on it if you'd like to. There's no way I would run that on a stock blower with no port. Sure you can do it and it has been done but a car with less boost more than likely would kill it in a race.
We're not even talking about if it's in the summer and 90*'s out. If I think my car is going to pull timing then I don't floor it generally. If I do I'll short shift to keep a little extra heat out of it and from hopefully pulling any timing.
Sure it's going to feel great but how do you know if the car is pulling timing at the top of 3rd gear or all of 4th? If you've never had that much power before chances are you won't know and will just think it runs great. Do it and run an upper only car to see who pulls who in the upper rpm's where it matters.
If my car was a daily driver it would be a 2.8 upper car or a 2.9/4lb combo because it'll peak really high in the rpm's and will not build much heat at all. Then you can have some spirited driving almost anytime you want to. Not pick and choose when the car is ready for it.
Hope that helps someone a little bit because do not get caught up on dyno numbers. You want "real world" numbers that are available when you want them to be.:beer:
You could run that 2.76/4lb combo on a ported blower on the street "if" you know when to crack on the car. That's not when you're sitting in traffic and get the first break in it to go full throttle. Cruise for a little bit and let the heat exchanger do its job and get some cooler fluid back under the blower to pull a little heat out and then crack on it if you'd like to. There's no way I would run that on a stock blower with no port. Sure you can do it and it has been done but a car with less boost more than likely would kill it in a race.
We're not even talking about if it's in the summer and 90*'s out. If I think my car is going to pull timing then I don't floor it generally. If I do I'll short shift to keep a little extra heat out of it and from hopefully pulling any timing.
Sure it's going to feel great but how do you know if the car is pulling timing at the top of 3rd gear or all of 4th? If you've never had that much power before chances are you won't know and will just think it runs great. Do it and run an upper only car to see who pulls who in the upper rpm's where it matters.
If my car was a daily driver it would be a 2.8 upper car or a 2.9/4lb combo because it'll peak really high in the rpm's and will not build much heat at all. Then you can have some spirited driving almost anytime you want to. Not pick and choose when the car is ready for it.
Hope that helps someone a little bit because do not get caught up on dyno numbers. You want "real world" numbers that are available when you want them to be.:beer:
No. Ran mine for years. 475/502 Tq. Picked up some with steg stage 4 port and reduced temps some; but not what people make it out to be!
Ran out of maf during dyno. Installed mafia and completed last 2 pulls.
Actually ran almost the same in the 1/8 mile. Ran strong out of the hole. Can tell it would heat soak in the 1/4 mile. Ran better times inthe 1/4 mile with 2.93 4lb lower !
Do it !!!
Ran out of maf during dyno. Installed mafia and completed last 2 pulls.
Actually ran almost the same in the 1/8 mile. Ran strong out of the hole. Can tell it would heat soak in the 1/4 mile. Ran better times inthe 1/4 mile with 2.93 4lb lower !
Do it !!!
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Let's keep things in perspective, Jake's car is a race car that doesn't see street duty. Make 4 back-to-back highway pulls with a stock Eaton, a 2.76 upper, and a 4lb lower and the car is going to run like shit. IAT2's will be ridiculous and the computer will pull timing like it's going out of style.
Just for perspective: I lost a motor doing 4 back to back freeway pulls. Lol
So what is better a 2.93/4lb or a 2.8/2lb. I have a 2.8/4lb cause that is what came with the trade but can tell on the dyno graph it flat lines in power at 6k torque is pretty damn good though. I have not got a revised tune yet from the logs but would be interesting to know.
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