Picked up a stock cobra a while back and got tired of being neck and neck with the newer maros and chargers ect. Mods right now are long tubes full borla exhaust and a handheld tune. Recently just picked up a posi ported eaton with a 2.76 upper. Also got my hands on a 4lb and 6lb lower. Other things I have picked up is posi ported dragon Tb/plenum,killer chiller ,BAP, mafia, 80lb injectors ,ford gt pumps ,and the modded fpdm to run e85 and am getting a NX kit from a buddy. I'm wondering has anybody ran a 2.76/2.8 6lb combo lately. Searching around I find minimal posts and most are outdated at that. I see efficiency post all the time and 2.9 4lb combos are the sweet spot blah blah blah lol so anybody who wasn't afraid to push there blower to the limits have any input? Thanks in advance
Anyone running a 2.76 6lb combo?
- Thread starter KillaCobra49
- Start date
Also have a fendwell jlt and the billet flow 4 piece idler kit
I've done some searching as well, some people say you don't want to push an Eaton past 17 lbs or so cause it could cause the rotors to flex and make contact with each other or the case, either would be very bad, but I have yet to find anyone this happened to. I think the main downside is the heat it will generate - you'll probably be pulling timing from high IAT's after just one run...
I plan to run 2.65/4lb combo on my stroker/longtubes/ported heads setup but it will only get me to around 15 lbs or so. I ran a 2.8/4lb combo on stock cobra longblock and stock manifolds and I would see 17lbs on cooler nights.
Go for it and let us know it goes!
I plan to run 2.65/4lb combo on my stroker/longtubes/ported heads setup but it will only get me to around 15 lbs or so. I ran a 2.8/4lb combo on stock cobra longblock and stock manifolds and I would see 17lbs on cooler nights.
Go for it and let us know it goes!
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The reason why you don't see the 2.76/6 combo on a large scale is it doesn't work very well, definitely not because people were afraid lol. Along with the super heated intake air your bigger problem will be belt slip. If you've not experienced the aggravation of belt slip and its associated massive power loss I'd keep that 4# lower handy. Super frustrating to hear that dreaded belt squeal/slip in the middle of a race and feel the cars power falling away and in some cases nose dive no matter what you do. The 2.76/4 wasn't about efficiency it was about reality. Super heated intake air and its associated timing reduction doesn't always equal more power. Every combo is different but 99% of folks didn't realize a marked improvement with the combo you're suggesting. Now when you spray (most folks didn't) that's a bit different. If you can fend off the belt slip, keep the bottle pressure consistent and have some traction then you'll be rewarded w/ a rather decent improvement. :thumbsup:
There is a reason why people post about efficiency with the eaton. Its not just blah blah blah and trying to push the blower harder and about fear. Its just overkill.
so you want to make your car faster by creating more heat, pulling timing, ruin the top end of the car, by running 20 21lbs of boost on a eaton m112.
The tvs 2.3L blower, even vmp will tell you, not to run the blower past 21lbs or 22 I forgot what justin said. You get the point... And thats a 2.3L tvs supercharger. The 2.9 whipple, even bigger, 25lbs is pushing it and will start to create more and more heat. so how can a 112 blower be fast with 21lbs of boost. If you want to trailer your car to the spot with bags of ice and not do back to back runs go ahead. If your cruisin around having a good time, you will blame it on the infamous culprit why you lost. Heat soak. The terminators worst enemy.
If you really want to go faster, do a tvs or throw a little dry shot on your eaton.
Keep in mind, people were dipping into the 10's way back in the day with a 2.80 upper 2lb lower with a ported eaton. There was no need to add extra heat by adding 40 more lbs of boost. The cars were more efficient and the times showed them. And this was before e85.
so you want to make your car faster by creating more heat, pulling timing, ruin the top end of the car, by running 20 21lbs of boost on a eaton m112.
The tvs 2.3L blower, even vmp will tell you, not to run the blower past 21lbs or 22 I forgot what justin said. You get the point... And thats a 2.3L tvs supercharger. The 2.9 whipple, even bigger, 25lbs is pushing it and will start to create more and more heat. so how can a 112 blower be fast with 21lbs of boost. If you want to trailer your car to the spot with bags of ice and not do back to back runs go ahead. If your cruisin around having a good time, you will blame it on the infamous culprit why you lost. Heat soak. The terminators worst enemy.
If you really want to go faster, do a tvs or throw a little dry shot on your eaton.
Keep in mind, people were dipping into the 10's way back in the day with a 2.80 upper 2lb lower with a ported eaton. There was no need to add extra heat by adding 40 more lbs of boost. The cars were more efficient and the times showed them. And this was before e85.
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I hear u guys and thank you for your input. What kind of setups have u guys run and what did u like? For the most part I hear the main culprit with running a combo this aggressive is the heat and timing issue, however I see people running a 2.65/4lb combo not having a problem so much with heat which is real close in blower rpms to the combo I am suggesting. Do u not think running a 3row radiator in combination with a killer chiller and e85 will be sufficient for battling the extra heat generated from the extra blower rpms, hence being able to keep the timing from getting knocked? Idk just have not seen to many people push the envelope with this eaton and more hear say. Shoot back in 05 I see posts that people were saying even throwing on a 2.76 upper by itself was crazy! Haha I'm just saying its a lot of people who are quick to say something is no good with no first hand experience and a whole lot of guessing. I'm mainly looking for someone who has tried a combo similar to this and failed. I believe passing through a post somewhere with POSI saying he ran this combo before however I don't know what his cooling setup was at the time
I would be interested in trying a 2.65/4lb combo if I could find a 2.65.. I believe they are no longer in production.
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I ran that briefly (came on my car when purchased). It was just a inferno.. I swapped it to a 3.1 upper and actually gained a couple rwhp more efficiently.
Cant remember exactly, but I had 530ish with full bolt ons and the 3.1 upper/6lb lower.
Cant remember exactly, but I had 530ish with full bolt ons and the 3.1 upper/6lb lower.
The 2.65/4lb combo your saying natedogg? Did u have Any cooling mods with it?
2.93and the 4 lbs lower have always been the sweet spot.
I would be curious to see a 2.76/4lb combo run against a 2.9/4lb combo and see how much of a difference it is, I hear about the "sweet spot" talk all the time hahaha
When I bought my car it had a 2.76 and 6#.. I eventually switched to the 3.1 and 6#.
No cooling mods at the time.
When speaking to the heat its not a matter of your coolant overheating. Its the heated intake air as a direct result of the elevated boost and as such the timing goes down, no even speaking to the potential belt slip. (high heat=power loss, belt slip=power loss...not winning either way)
I ran a 2.76/3#/port/spray combo for 30k miles and loved it but keep in mind this was back in 04-06. Didn't have Killer Chillers and such, which is why I ran a dry 100-150 shot. I knew seeing 18-19psi was creating a lot of elevated hot air which needed to be addressed if I wanted more power w/o going Whipple/KB. The low end was amazing but you can feel the heat soak after just a few runs. At that point it was a matter of clutch(on spray), available traction and belt slip. If I were to do it again I'd prob go w/ the 3.1/6/port & Killer Chiller or just get the VMP blower and keep it simple.
I ran a 2.76/3#/port/spray combo for 30k miles and loved it but keep in mind this was back in 04-06. Didn't have Killer Chillers and such, which is why I ran a dry 100-150 shot. I knew seeing 18-19psi was creating a lot of elevated hot air which needed to be addressed if I wanted more power w/o going Whipple/KB. The low end was amazing but you can feel the heat soak after just a few runs. At that point it was a matter of clutch(on spray), available traction and belt slip. If I were to do it again I'd prob go w/ the 3.1/6/port & Killer Chiller or just get the VMP blower and keep it simple.
Thanks for the input MYSTI, beautiful car BTW one day when more funds are available I will have one of those sexy beeches in my driveway LOL. I think I might put the 6lb lower and keep a 2.9 handy just incase shit hits the fan with the 2.76 upper. I want an eaton street monster!! I've seen a couple people with 2.8/6lb combos that are ranked up near the top in the fastest blower only quarter mile. I'm unsure what other mods they had tho
It's done at that point and won't add any hp and probably hardly any torque if you run a 2.76 or a 2.8 with a 6lb. lower. The difference in a 2.9/4lb lower and the 6lb is you get that last bit of hp out of the little ported Eaton and some extra torque. I know of 1 person that runs this but they haven't ran their car in years. He is on the 10 second club though.
Don't worry about IAT's with the KC either. I'd run the 2.76/4lb combo if I were you and let it eat!
Don't worry about IAT's with the KC either. I'd run the 2.76/4lb combo if I were you and let it eat!
I just want to make it on the 10 second eaton only list posi lol how do I do it is it possible with the 2.76/4lb setup? Or should I go 2.65/4 or 2.9/6 I just want to maximize my use out of this eaton
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