What size injectors and throttle body would be recommended for 700-1200 horsepower range? Ranging from pump gas to race fuel. Alternatively, what would be recommended if I choose to burn alcohol? Trying to decide if I should use my classic FAST box or stick with a carb.

 

90 mm tb. alcohol I would use 160lb. 100lb. would be good for gas. is this for a natural aspirated or turbo?

 

Depending on budget, Id look at ID2000 injectors. They're responsive enough that even at that lower end on gas it'll be super drivable and yet provide enough fuel for anything you'd ever want to throw at it

Here is a cold start on them with a cable driven Aeromotive billet hex drive. No priming pump.

Excuse the iPhone mic going to hell.
http://youtu.be/sz7kseEO1Oo

 

Those ID2000 injectors are definitely out of my budget. Will I have trouble with the 160lb injectors on the street? I was told it's not possible to clean up the idle characteristics with that large of an injector. BTW This is a twin turbo application.

 

I would like to have the ability to try different fuels but don't want to sacrifice drivability. Am I asking too much without a staged injection system?

 

The newer 160# injectors might work. I think the problem would be if you weren't running sequential fuel injection with the Fast.

 

90mm would be the safe bet. Injectors for fuel/e85 and methanol all will vastly support different power. If your gas only, 120's can get the job done. 160's for gas/e85 however you'll need to work on the idle abit more on gas. Methanol is a different ball of wax and you need volume...time to step up and spend for some 225+lb

 

I have been trying to get my car to idle below 1000 rpm with 160's. some of the problem is I don't have sequential injection. I do get a little out of switching from simultaneous to alternating firing the injectors. some of problems is the cam (idles at 67 kpa duration is 270 @ .050 lift) some of the problem is distribution at low air speed causes fuel to enter on the wrong cylinder with carb type intakes (needs a upper intake to cushion reversion pulses).

 

FAST Classic doesnt support Sequential as far as I know.

 

The early FAST box was Bank to Bank. but the newer versions were also available in sequential. I have a Sequential box.

 

When you say newer versions, you mean XFI right?

 

You could get an old fast box in both sequential and bank to bank. The sequential option was more money than it was worth back in the day..

 

Its an old grey FAST Sequential box. Old skool but they still work fine, without all the fancy options like the new stuff. I know guys that were running in the 7's with these old boxes.

 

If you are talking hi-z 160 Bosch, I am using them now and they idle fine on my little 5.3 motor. I have heard of people hving issues with them on e85, but, fingers crossed they are doing fine for me so far. I have heard the same issues with the Id2000s, but have tunes those too. Those were very tricky to idle on a 4 banger anywhere near stoich, bit in open loop I was able to just fine. It just takes time and lots of patience.