Best upper combo w/8lb lower ??? (stock blower)

[BIGONTS]

Please reply if you had experience with this combo. I just purchased an 8lb lower and deciding on which upper to go with. With my old 4lb lower, I was running a 2.93 and the car moved out really good. I decided to switch it up and go with a 8lb lower to see if I get better results. I'm trying to go the fastest with a unported blower this year and maybe KB next year. I have the Billetflow pulley system and these are my options:

Billetflow"Typical boost gains over stock pulley (3.65")"

1.5-2.5 lbs. 3.400"
3.5-4.5 lbs. 3.100"
5-6 lbs. 2.930"
6-7 lbs. 2.760"

Right now, I think I will go with the 3.4 upper. What do you guys think?

I already have the alt pulley w/PA alt. and some cooling mods LFP HE and res. tank which should be fine for now. What other mods would I need? BAP, 60inj, SCT MAF??? The person I bought it off of had great results with the stock upper pulley with cooling mods but no BAP, meter or injectors. He works and got his car tuned at Speed Inc. which is a very reputable performance shop in the Chicagoland area. Billetflow does make a stock size pulley so I can have everything match.

About my tune, I still have to call Hermann. I don think I will need a retune. My car was tuned to run that much boost with my 4lb/2.93 combo. I think I will run the same boost but it will just kick in earlier and make more torque. It would jump up to 18 and back down to 14-15lbs.

Thanks :-D

 

[mobius]

with stock blower noupper... with ported go 3.4. 3.1 is a bit toomuch but a 6/3.1 is perfect...

 

[BIGONTS]

ttt, am I the only one that will be running a 8lb lower?

 

[Jdaniel]

WOW! An 8 lb lower on a stock blower seems to be a lot. Im running a 6 lb lower and a 3.5 upper on my KB and seeing 18 lbs of boost. You may very well overspin a stock eaton at those rpms!

 

[04torchred]

ttt, am I the only one that will be running a 8lb lower?

No I am going to be running one soon, but I am sticking to the stock upper till I port the blower. Then I will add a 3.4 or maybe get a pulley built in the 3.2-3.3 range. Stock blower I wouldn't run more then the 8lb, just too much heat to really give you the benefits you are after. See how much boost the lower gives first, it isn't going to slip like a 2.76 or 2.8" upper will.

 

[BIGONTS]

WOW! An 8 lb lower on a stock blower seems to be a lot. Im running a 6 lb lower and a 3.5 upper on my KB and seeing 18 lbs of boost. You may very well overspin a stock eaton at those rpms!

I don't think it's really pushing it with a stock upper and a pretty common set up. I'm just trying to get some feedback from those who have experience with the set up. It's like running at 2.76 upper but, getting the boost earlier and holding it because of less belt slip.

A KB and a stock eaton are two totally different blowers. You are moving waaay more air at 18lbs with a KB then a stock blower will ever move ported or not at any boost levels. You can also go higher and not loose efficiency of generate heat. That's why you need better gas, tune, etc..

 

[mobius]

I don't think it's really pushing it with a stock upper and a pretty common set up. I'm just trying to get some feedback from those who have experience with the set up. It's like running at 2.76 upper but, getting the boost earlier and holding it because of less belt slip.

A KB and a stock eaton are two totally different blowers. You are moving waaay more air at 18lbs with a KB then a stock blower will ever move ported or not at any boost levels. You can also go higher and not loose efficiency of generate heat. That's why you need better gas, tune, etc..

8 is no problem on stock blower. i see about 15lbs of boost...
going at least8/3.4 onported blower maybe 6/3.1

 

[BIGONTS]

TTT, Anyone else has any input?? stock or 3.4???