LT1 POWR

I will be purchasing a D1SC shortly and would like to install it on my bolt on LT1. I just want 6-8psi for now, enough to hold me over until I rebuild within a year. It doesn't come with a FMU, but I know a guy that does amazing dyno tunes with LT1's. He ownes a few, so he knows his stuff. Is it possible to use the stock injectors with this kind of boost? Will I need a better fuel pump?

Also I plan on building a FMIC setup. Is there any type or brand of intercooler I should look for or is it "an intercoolers an intercooler" type deal? Cause I've noticed there is a big price difference between some of the FMIC's that I've seen.

CrazyLT1

If you are getting it dyno-tuned - then the best way to do it would be to buy some larger injectors and not use an FMU. There are used sets of 36 lb. injectors for sale a lot on this board for fairly cheap.

But, if you decide to keep the FMU - then you can probably get away with keeping the stock injectors and long as you keep the boost around 6 lbs. The FMU basically tricks the system by building up extra fuel pressure.

Regarding the FMIC - I am not too familiar with them. I am more familiar with aftercoolers and methanol injection. So I'm not too sure if one is better than the other, etc.

LT1 POWR

It doesn't come with a FMU, so I will probably use the stock injectors if possible, buy bigger injectors, or get a FMU. But I'd like to stay away from a FMU if possible.

Is it possible to not use a FMU and use the stock injectors with a dyno tune. Or will I either need a FMU or bigger injectors?

I will be doing a 383 with a D1SC in the future, so if I have to get injectors now, what should I look for that will work on both the 350 D1SC with 6-8psi and the 383 D1SC with about 15psi, so I wont have to buy injectors twice?

Boosted_Z28

If you only want to purchase injectors once, then you will have to use the FMU and still tune the PCM...not my first choice, but if the FMU is in good working order, then this method will work. The biggest problem is the fact that you're are going to be at the opposite ends of the fuel spectrum with a stock 350 CI motor running 5-6 lbs of boost and then a 383 CI motor with 15 lbs of boost. Each have completely different fueling requirements. You should also consider upgrading your fuel pump if you haven't already.

I would consider not using the FMU, looking for some used 42# injectors and a good safe tune and a walbro 255 fuel pump when putting boost to the stock motor, then upgrading to larger injectors when you make the swap to the 383.

Running an intercooler with the stock motor may be the single most important step in keeping the stock motor together. Although water injection is another good alternative as well. If you choose the intercooler route, then purchase the largest one you can fit on your car. If you don't mind a little fab work you can purchase the parts seperately and actually save some money.

LT1 POWR

I planned on fabbing up a FMIC setup, unless there is a bolt on kit already out there somewhere.

So I should look for 42lb injectors for the stock motor, and a 255lph pump, then get a dyno tune and not worry about a FMU? What about when I get the 383, what size injectors then. Also low or high impedance?

maro z28

Probably high impedance. I can't exactly remember, but you have to change out some **** to go to low impedance fuel injectors. (look up Precision fuel injectors, they explain what you have to do to go to low impedance injectors.) They make high impedance injectors up to at least 65lbs/hr. That plenty for your application.

rickys93z

go with 60# mortonns(spelling?) and upgrade your fuel pump that what i had to do with just myP1SC

Eric@Victory Racing

60# Mototron $409.99 Shipped

95 Z/28 LT1

I've only heard great things about the 60 lb mototrons and that price from Victory Racing Engines will be tough to beat.

LT1 POWR

Will those 60# injectors work with both the stock 350 with 6-8psi and the 383 with about 15psi? I'm hoping for around 700-800 hp with the 383 the D1SC and some NO2.

maro z28

you can get that w/out the nitrous even. You should be able to get there with 15psi. Assuming your starting with at least 350rwhp NA.

CALL911

I am running the 60# Mototron injectors in my setup in the Z in my sig. It will support power levels up to 900 RWHP, so you should be fine. As for intercoolers, after about 6-8#'s, the twin intercoolers from ATI pretty much won't be able to keep up with the boost as far as keeping your IAT's low. I strongly reccomend getting a large FMIC. There is only one company who makes and sells them currently, and it is the same place I got mine. EPP (exotic performance plus).

IMO, even if you get a safe tune, and upgrade to a nice big fuel system, along with a FMIC, if you plan on running even 6-8#'s on the stock motor, I would expect you probably will be needing that rebuild sooner than you might expect.

Good luck!

VK

What he said ^

Just read the sig.. my stock motor lasted ~2-3 weeks

LT1 POWR

I was looking at some FMIC's on ebay and I found almost the exact same thing from GODSPEED for a little less $, but will probably go with one of the EPP's.

Why is their FMIC kit so much? I'm sure I could build the same thing for less than half the cost and a little fabrication time.

What about a fuel pump, I see a lot of people are running dual 255lph's. Is there a kit out there that is just plug and play, or is this a custom thing.

So will 60# injectors and dual 255lph pumps support around 800ish hp?

Are stock fuel lines and the stock fuel rails good, or will they need to be upgraded?

Will the stock PCM and MAF sensor work with this kind of power, or will I have to do a speed density tune? What is this Mass Airflow Massager that ATI sells? It says its mandatory for 96-97 LT1's.

Any other advice is welcome.

joe-96z1le

The dual pump setup should have no problem at that HP level. The stock lines and rails might be OK too. The MAF massager that ATI sells is used to keep the MAF sensor from triggering a trouble code. When airflow gets too high across the MAF, the code is set. No need to buy the MAF massager, though, since a tuner can fix this situation with programming.