quick, probably already been asked question

[miata nut]

is it possible to do away with the second pc pro, and 5th inject all together and just go with some larger injectors say... RC550? or maybe something smaller?? im not new to mechanics, however i do have a limited amount of knowledge when it comes to miatas and supercharging. mainly messed around with turbo 240sx's

[chuckerants]

is it possible to do away with the second pc pro, and 5th inject all together and just go with some larger injectors say... RC550? or maybe something smaller?? im not new to mechanics, however i do have a limited amount of knowledge when it comes to miatas and supercharging. mainly messed around with turbo 240sx's

#1. That depends on whether or not the stock ECU can make the bigger injectors idle correctly. 550cc would probably be a tad too big for the stock ECU.

#2. The 5th injector isn't just about adding fuel. It's helping to cool the intake charge by evaporation hence the moniker, "e-Cool".

I've asked this question of the turbo guys and they seem to prefer larger injectors over adding additional injectors.

[miata nut]

AH.... thank you for the explanation, would taken me alot longer to figure that out haha.

yeah, turbo guys like the bigger injectors rather than the 5th because its easier to tune from cylinder to cylinder.

[miata nut]

oh almost forgot.... ive also heard about smaller... but bigger injectors, ya know the 2001 miata injectors, would those work with factor computer?

[Mark]

When I did the install on my 95, I found little cracks in the tips of stock injectors. I didn't want to get everything together and then find out they were kaput. So based on Tom's suggestion, I got new 280cc injectors, just a bit larger than stock. I've not had any idle issues at all.

[socal pat]

I've heard that the factory ECU can handle up to around 310 injectors. After that and idle /driveability issues can happen. The whole design idea behind Tom's kits is "Install kit, turn key, enjoy" not buy kit, substitute parts, tune and tune again. For the big injectors you would need something like the old Hotside BRP R4 manifold and at least a piggyback if not a standalone ECU. You can make it work.

[chuckerants]

The 01+ injectors are 270cc and should idle without any problems with the stock ECU. Any larger and the chances that you'll have idle issues increase.

[socal pat]

here is a good thread on injector flow rates. http://forum.miata.net/vb/showthread.php?t=153952&highlight=injector+flow+rates

[miata nut]

thanks for all the info guys! much appriated. anyway i know toms kit is supposed to be "turn key and enjoy" and it looks to be that way already, i just kinda like to got by a rule of thumb that i made up "safe is good, safer is better" hahah so its not proper english but you know what i mean. hey why would i need the hotside manifold if i just went with the 01 injectors? im sure the answer is sommething i over looked and gunna feel like an idiot about after you tell me, but.... what the h***

[miata nut]

pat you seem to know these chargers pretty in depth, and your in temecula so dont be surprised if im sending your a PM when i get my kit to come help me install on my miata :chinese: excuse the chinese hat, its the best smiley they had

[socal pat]

Heh, first of all I only know what I know. When I made the remark Re: the R4 manifold I didn't know you were ordering a coldside kit, and I was also referring only to the 550 injectors, not the '01's. I will be installing the '01 injectors on my '00. I just wrote a check for over $3,000 to build my new motor and I know what you mean about safe. When the time comes give me a shout and I'll come a runnin'. I see you're in San Jacinto. I am actually in Sun City, but my wifey teaches in San Jac.

[miata nut]

nice! local fellow miata folks is always a plus. OHHHH... yeah i see what your saying now..... funny you wife teaches at a school in san jac. cause i live like right across the street from one... wierd... :confused: haha, anyway