Hey what are you guys using? I use a 2.8 upper and 2lb lower. What is the difference on swapping to a 4lb lower? I would Like to know your opinions. Thanks, jared
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4lb or 2lb lower?
- Thread starter greensvtcobra99
- Start date
IMO adding a 4lb lower with a 2.80 upper, you would be running too much boost. I had a 2.76/4lb lower which put out 20lbs of boost, not good especially on 93 octane. Plus, the blower heats up much faster, pulling timing. I'd stick with your combo. The slight gain wouldn't be worth it.
hmmmm that is what I was thinking would happen. I do not know where to go from here as far as gaining horsepower except larger injectors, but does that really do much? Anyone believe in the SP boost cooler with the methyl injection in it? I still have factory manifolds on the car. Are the JBA shorties even worth the price for cost/labor?
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I never would go past 2.93/4#...and I'm the kind that would try to get all the horsepower that I could out of it. +1 about running too much boost with the 2.8/4#
Machinator
Banned
I had a 2.8 4lb lower and didnt get great results, lots of torque but the power suffered on top because of the heat. I would suggest a 4lb and a 2.93 upper maximum.
I believe the 2.9 upper and 4 lb lower are a perfect combo!! My vert made 475 rwhp and 518 rwt with that combo and a cai! With a ported blower,the results would have been spectacular!!!
my ported eaton with a 2.8 upper and a 4lb lower made 539.1rwhp and 585.2rwtq
so what you are saying is that if you already have a 2.76 then just go with a 2# lower?
even if I have the billet flow slack adjuster thingy, I know real technical term.
If you have a good double pass through heat exchanger, good tune, all the supporting mods including long tubes to help out with heat issues, you can pull off a 2.76/4lb combo. The most hp out of an Eaton car had this combo. If it were me, I'd also get the Evan's cooling mod just for the added insurance. But the only way I'd get this combo is with a Stage IV port.
Jason
Jason
With a upper 2.93 and my mods (ported blower, etc) I currently have the stock lower. It dynoed at 480HP and 481 lbs of torque. How much HP gain with a 4lb lower? Do I need to retune?
I don't think that would be the case with a ported blower especially if you have a good HE and resevoir. Just my .02NHRACobra said:
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MarcInHawaii said:
Most of the 2.93/4 combos are pushing 500-520 hp, 500-530 tq.
You may need a retune, at least check it out on a dyno. You will need a retune if you add a new MAF or mafia.
With your 480 hp, you are at the limit of the stock fuel pumps and MAF.
I'm running a 2.8/2lb combo and had to add a BAP and Mafia.
lthlsnake said:
You must be able to melt solder on your blower. I have a 2.8 upper and 2lb lower with a stage 4 port and my underhood temps are just stupid. I know it was never that hot last year with just my 2.8 upper. I'm sure we're majorly killing our motors longevity.
cdh027-2 said:
What do you have in the way of exhaust, heat exchanger, or a cooling mod? Personally, this is where coated long tube headers would help.
Jason
Here are my Mods. I want to go with the 2lb lower after doing some research. How much HP gain to the rear wheels do you think I will see with these mods?
DiabloSport Predator custom tuned by Coastal Dyno
2.93 Pulley
MotoBlu Idler
Pro 5.0 Shifter for Tremmec T56
Accufab Single Blade Throttle Body and Intake Plennum (Polished)
Apten Ported Eaton Supercharger (Intake Plenum port-matched)
Mac Cold Air Intake
Bassani X Pipe without Cats
Flowmaster Cat-Back Exhaust
LFP Water to Air Intercooler with Water Wetter
Innovate LM1 WideBand Air/Fuel Meter
DiabloSport Predator custom tuned by Coastal Dyno
2.93 Pulley
MotoBlu Idler
Pro 5.0 Shifter for Tremmec T56
Accufab Single Blade Throttle Body and Intake Plennum (Polished)
Apten Ported Eaton Supercharger (Intake Plenum port-matched)
Mac Cold Air Intake
Bassani X Pipe without Cats
Flowmaster Cat-Back Exhaust
LFP Water to Air Intercooler with Water Wetter
Innovate LM1 WideBand Air/Fuel Meter
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