So I want to start by saying the car is a DD, ZZP 3.0" pulley, 42lb's, injen cai, Ported LS4TB/Rebels plate, DVO Stg 2 meth, Ported M62, LNF 2.5" catback, CXR H/E, CXR H/E pump and SGM Tuned, im pretty happy with the car but am still curious as to how much power can be gained. I will not put a header on the car, I am thinking of experimenting with opening up the stock ex manifold and doing a ZZP catted DP. But the car sounds exactly how I want and I do not wish to change that. I know the 2.8 will push the 42's past there limits, but with the d05 nozzle on the car now it should keep IDC's within reason. I just feel like with all of the airflow mods I have on the exhaust side a 3.0 is hurting what the car can potentially do. Opinions? Yes i know exhaust mod's are more then in order, so please dont rant with that. 2.8 or no?

 

FWIW i run a 50/50 mix of meth. Pump has output psi increased.

 

Care to elaborate how aggressive your tuning your car?

The 5gph will assist in providing 42 lb injectors with enough fuel to run the 2.8

My recommendation is to step it up to a 7gph on 50/50. It will provide better cooling, more fuel, and ultimately let you run a more aggressive tune safely.

The stock exhaust manifold is cast iron; unless you like going through bits... I recommend you leave it alone, buy a GM honed & extruded exhaust manifold. Otherwise purchase a BADMAB shorty header, put the heat shield over it and call it a day.

 

Sure, I tapered the timing up from 4300 - 6850(redline), Starts at 22* and taper's to 25, AFR is tapered aswell from 11.4-11.9, I understand this is semi rich for meth and semi aggressive on the tune, but I like to keep it safe. I will order a 7gph nozzle tonight, and also looking into a bad-mab as we speak, Ive been meaning to ask you aswell, I have 3 gallons of devil's own brew that is about two years old, but is unopened and hasnt gotten hot, what point would you consider meth "bad"? Thanks in advance.

 

All meth is bad you want to buy my pacesetter lsj header?

 

2 year old methanol ....

Personally I don't let methanol sit for longer than 6 months at a time, but that's because I need to fill up a 5 gallon jug every 6 months lol.

I'd have to actually see your table, but 22* @ 4300 isn't bad. Relatively aggressive, but there's still more room to grow.

The less timing in the midrange, the easier it is to run more on the top end.

11.6-12.0, meth or not on meth hardly has any difference.

The badmab is a greater cheap solution to a stock location exhaust manifold. Gains a proven 10+ whp

 

here's a good read for you

FUELING TIPS

https://www.cobaltss.net/forums/dyno...s-fact-230350/

 

Lol of semi rich is 11.4-.9. Consider me filthly rich. 10.1 smh I need a retune.

I go through plugs like I go thru chicks

 

Lol...

yeah anything south of 11.0 is filthy ******* rich on these cars... BUH BYE CATS....

11.5-11.8 is the magic number with LSJs

 

Very interesting read, wondering though, If sloping the AFR alone is ineffective, would it give the tuner more Le-weigh with timing on an aggressive tune?

 

BINGO

your on the right track

A leaner to less lean condition allows more timing under the curve

 

Surprised it doesn't start to break up around 10.1. lol

 

The real question though...

When your hunting for those few extra degrees of timing... is it really worth your while? A flat 11.8 AFR from start to finish allows A LOT of room for growth

 

I am going to order a badmab, 7gph nozzle, and a 2.8 and get some seat time on the dyno, very interesting concept's I am learning on here, It is a bit different then tuning the usual LSx car's I have experience with. I will be sure to put up the chart's once the car is ready.

 

Very true, Im sure just like any car, it will reach its peak efficiency, and the gains will be start getting minimal vs the extra stress/risk being put on the engine.

 

I have no cat. But if I do half throttle accel I'll get a bunch of jerking around and yea so I don't do that I'll cruise slowly up to speed or wot. No such thing has half throttle accel here

 

Is the car tuned at all?

 

Does anyone know how to get ahold of SGM Tuning in Shrewsberry?