I just got off the phone with a tech from Marren Fuel regarding a set of injectors I sent to them to get cleaned/balanced. I sent a pair of 550cc side feeds and a pair of 1600cc top feeds. Keep in mind that these injectors were last cleaned/balanced 15,000 miles ago, along with using new fuel filters every 5-7k miles. According to the tech, the 1600's were fine, but one of the 550's was flowing 6-7% lower than the other. I'm signed up to tune with Steve Kahn Sept 10th, and I'm glad this issue came about now.

I guess this is a perfect excuse to finally put 850's in the primaries.

 

check your PM's Jehan

 

Better off with 850s in primaries...

 

What power would 1000cc primaries and 1600cc secondaries support?

 

youd never idle. . .

. . . fourty. . . seriously. rethink your decision to run 850s in the primary rail. your idle will be richer than you desire and youll foul out plugs all the time. its fine when youre driving down the road, but at idle. . . its hell on the engine. . . and with fuel prices the way they are. . . geh. . . 550s!!!!

 

how about using a injector cleaner from autozone? would that work?

 

I recently lost an engine to this I believe.... AFR's were fine under boost, but one of the 1600's was flowing 150cc less than the other and one of the 850's was about 70cc's low. Definately worth the 100-150 you pay for this service.

 

Yea .. this was more of just a public service announcement for those of you running high hp motors. Everyone, even with a good tune, will be riding on a thin line if something simple like injectors are performing up to par.

Rotorbrain, as far as gas prices, the car isnt driven all that much so ..
But with all the searches Ive done, the consensus really isnt out on whether 850's will really cause a bad idle. I guess there are different factors to take into account. I'm tuning with Steve in 2 weeks, so I think (or hope) that we can come to a tune where the idle is stable. But also keep in mind that I have my idle set to about 1krpms ....

 

Our race car has 6 1600cc injectors with an AEM and the new injector driver that just came out and it idles fine. Before the injector driver came out we had some problems with idle. It can be done, especially with only 850s in a 13B, its all dependant on the ems.

 

fuel injector cleaners are probably meant for just routine maintainence/cleaning. they dont really get the injectors all that clean. send them to a place that can flow test and do some sort of sonic cleaning.

 

steves doing the tuning??? youll be fine. . . especially with an idle set at 1krpms.

my idle is "okay". it suges just a TAD bit. not horrbly bad, but enough for the guy driving it to notice and of course. . . want it fixed. hahahaha

 

Idle will not be a problem even with 1000-1300 as long as the tune, and EMS are up to it. All the popular ones for rotaries will handle it NP. As for mileage, also, tuning, no other effect. Cost is 60.00 shipped, not 100-150.00. My buddies Supra idles perfectly with six 1200cc injectors controlled by a VPC/GCC. If piggy backs can do it, and EMS surely can(assuming a competent tuner). Carl

 

Since several people asked, I reccomend
http://witchhunter.com/

Faster, and cheaper than RC

 

you can try ron ,at ronsperformance.us, been doing injectors for 20 yrs.

 

yea idle is all on the tune. I had 4 1600cc and it idle perfectly.. now i got 4 1000cc and its perfect at 750rpm

 

Normally , the 550's are a very reliable and consistant flowing injector. We use one for our "house standard", to check the flow machines and for a sanity check if something isn't looking right.
The 850's flows are known to vary a bit, normally to the high side.

Like you said, a good excuse to put something bigger in.

Gordon
Witchhunter Performance
InjectorServices
Fuel injector cleaning & flow testing