I have a 1990 IrocZ B2L G92 car with parts on it, and im trying to get the blms to 128 under part throttle, but im finding that some of the values (ve tables) are gettign close to maxing out, the closer i get to 128. I was wondering if thiers anyway of getting more resolution so i can modify it more. I was thinking I might need bigger injectors because its asking more and more fuel, does sound right? And if so, is there a general rule of thumb regarding injector sizing?

 

Ok, Ive done a little more research on my problem and came up with some solutions but im not real sure on this...
anyways, the car is a b2l 730 ecm with the stock injectors, modified tpi unit (slp runners) headers, exhaust igniton intake tranny work 2800 stall trq convertor etc....

The most likely way of getting more room to play would be to change the injector constant, by what i have read. If i were to lower the constant, it would richen the ve tables up, and if I increased the inj. constant then it would lean it out. Is this the best way of doing things or would bigger injectors be the "proper" way of doing it. Any help would be greatly appreciated.

 

That's right.

 

You can play with the injector size a LITTLE. Remember thou, changing it is going to mess with the WOT fuel calculation. Changing by a couple pounds, OK, but anything more then that and your out of injector.

Just to make the math easy:

If you 350, stock made 200 HP with 24#/Hr injectors, and you make enough mods that your now making 300 HP (real HP, not pony stuff), then you need 36#/Hr injectors. The oem ecm is set up to deal with ratios, you just can't increase the HP 50% and expect to make changes in the calibration to allow for that HP increase.

Now, in an aftermarket ecm they run the code very differently, and can quote unquote get more out of an injector, and you can do the 2HP per pound of fuel calc., and size your injectors accordingly.

 

Is there a formula to find out the ratio to figure out what size injectors I need or do I just buy bigger like 30lbers and play with the inejctor constant if thier slightly to big?

 

I don't think you need bigger injectors than 22 lbr's but instead have some sort of mechanical problem. Fuel pressure or faulty/dirty injectors would be my guess. ON the average a 24 lb inj. will feed 350 hp so I would think a 30 lb is way too much. I would just try a fuel press change and see what happens.