Working around a doubling of injector size

[wcbjr]

Can I use a bi-intake system with the stock MAF on only one side? The MAF only reads half the air flow and only sends out half the fuel, which is really the fuel I need due to the double-sized injectors?

[PROJECTRB240SX]

JUST MAKE SURE THE BI FLOW IS OF EQUAL LENGTH AND GETTING AIR FROM THE SAME AIR FLOW.

[wcbjr]

That's what I thought.

I think it is cheaper to use my stock RB20 MAF and extra pipe and filter than to buy a Z32 MAF and computer mods.

[PROJECTRB240SX]

THAT YOU WOULD HAVE TO FIGURE OUT.

[wcbjr]

Only thing I could see being a problem is tip-in and cold starts. IIRC, the ECU sends out a few more injector pulses that have nothing to do with air flow. But that's the same as almost any piggyback.

[FAST-DATSUN]

I would not try it as if the air flow is not the same you go lean (boom) up grade the computer and install the correct size injector for the power you expect...I will live longer...

[PROJECTRB240SX]

HEY MACK,HOW MUCH FOR RB25 CRANK AND RODS?

[PROJECTRB240SX]

I TRIED CALLING BUT NOW ANSWER AND YOU NEVER ANSWERED MY POST EARLIER.

[wcbjr]

I will still tune with someone else's wideband or a simple O2 gauge. Just like I would if I had expensive electronics. It's not like I am using separate intakes for different cylinders.

[McAdam]

hey man, there is a guy that has a hacked maf on freshalloy.com. he did basically what your are doing. he has a "Hacked MAF". he also had a JWT ECU with the bigger injectors. the hacked maf gave him more power and more torque than the JWT computer, he has dyno charts to prove. it also lowered his A/F ratios by abot half a point. so, do what ya want.

If you double AFM size, step up to a injector with room for error, like one that is 110% bigger insteead of just 100%.

[wcbjr]

If you double AFM size, step up to a injector with room for error, like one that is 110% bigger insteead of just 100%.

That's exactly what I am doing. I am going from the stock 270cc to 550cc RX7 injectors.

[wcbjr]

Does anyone have access to Autospeed articles? I'd like to read this one.

http://www.autospeed.com/cms/A_1874/article.html

Notice the MAF in the picture.

[PROJECTRB240SX]

ARE THOSE STOCK RX7 INJECTORS?

[wcbjr]

I believe so.

[PROJECTRB240SX]

I CAN GET THOSE FOR DIRT CHEAP BRAND NEW, WHAT YEAR ARE THEY?

[wcbjr]

How cheap can you get them? Where from?

[FAST-DATSUN]

I have just a bare empty block......

[PROJECTRB240SX]

That sucks, I need all the internals minus the pistons.

I work for a fleet so I can get alot of parts for cheap, I need to know what year and if it is a primary or secondary injector. Its probably going to be around $60 an injector.

[wcbjr]

From http://www.meggala.com

Common upgradesRB20

high impedance top feed.the main choice is from the series 5 rx 7. these are 550cc injectors (they are denso and the part number is 195500-2020).nismo make 2 as well 550 and 600 cc.But I believe that you can use low impedacnce injectors with a resistor pack from a gtr this has not been confirmed.



FC3S TurboII I think

I just got 4 off eBay for $105, got 4 more coming for $100.

http://cgi.ebay.com/ebaymotors...26948

[PROJECTRB240SX]

I can get them rebuilt for $63.09 per injector so thats replugged, replaced disk and shot cleaned or $79.34 brand new.

[wcbjr]

I just got an email saying the used RX7 injectors are from 89-91 models, if that helps.

I will be test fitting them as soon as they arrive and let you all know.

[PROJECTRB240SX]

I LOOKED AT PRICING FOR A 91 MODEL THATS WHAT THOSE PRICES ARE FOR. THANKS I THINK I'M GOING TO DO IT THAT WAY INSTEAD OF BUYING NISMO ONES OR STUFF LIKE THAT.