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-   -   1600cc injector woes (https://www.rx7club.com/single-turbo-rx-7s-23/1600cc-injector-woes-41155/)

zkeller 12-26-01 03:01 PM

1600cc injector woes
 
I have been reading everyones post on the 1600cc injectors and the Power FC. I desided to go with the 1600s because of some mixed reviews with oversizing the 850s.

I have the luxury of borrowing a wideband O2 and will be tuning my car to acheive an air fuel of 11.8:1 to 12.2:1 across the board.

This may be a week or so since I had to pull my T04S for a rebuild today!, (oil was everywhere!). I will post the fuel maps as soon as I am finished with the tuning. I am going to be running 17PSI of boost. Left the 550s in the primary as per Dave at KDR. I plan to leave the timing as it was sent by Apexi for now.


My engine mods are as follows:

-XS-Engineering T04S single kit
-Midpipe with a soon to be fitted Borla XR1 race muffler
-HKS SuperDragger catback,(newer less restricted version)
-RX7.com 1600cc fuel kit with adjustable regulator and upgrded fuel pump, stock 550s in the primary
-KDR street ported motor
-Greddy stock mount with Pettit duct, (works great with the Pettit duct!)
-Unorthadox underdrive pulley
-8.5lbs flywheel

vosko 12-26-01 04:11 PM

good luck. i think 1600's really need powerxl software to tune correctly......

Jedon 12-26-01 06:25 PM

The powerFC limits you to 1300cc injectors I think, something like that, certainly not 1600 but you can trick it by setting it to lower cc injector combo of the same ratio. I don't have my car right now so can't check, can someone else post the correct lower cc combo to use? Then you lower the duty cycles to compensate for the larger than you told it injectors. The important thing is that the ratio of primary to secondary injectors is correct.
-Jedon

vosko 12-26-01 07:27 PM

the newer PFC's will go up to 1500cc .... but tuning is a key issue

wankawankel 12-26-01 10:13 PM

Amen to that. Now does anyone have the excel software and dyno to do that? :eek:

zkeller 12-26-01 10:25 PM

I talked to Ari at rx7.com personally and he said to set the FC as high as it will go, (1500cc). NOBODY can safely say that they are happy with the 1600s and the FC.

I am assuming that all of us who have the 1600cc injectors are using Ari's kit or have bought the rail and made thier own. Has anyone researched and found a 1300cc top feed, low Imp. injector that will snap right into the rail? Ari's kit is great but there are issues with the Power FC. You know something is up when XS does not even have a map for the 1600's.

I would like to help get a solid fix for the "incompatibilty".

wankawankel 12-26-01 10:29 PM

No one runs their monster TO4X2. None of their other turbo kits would need the 1600cc treatment. So why would XS bother?

vosko 12-27-01 12:24 AM

the only way to get 1300cc secondaries is to take your 850's out and send them to www.rceng.com to have them bored to 1300cc costs like $150 per injector. i did alot of research. if you are running very large injectors and a large turbo on the east coast you are better with a haltech. there are a large number of very good haltech tuners over here and MANY race cars are running haltechs without blowing engines. this is the whole reasoning i sold apexi pfc and boost kit it would not work the way i wanted it to work. just ask wankawankel. PFC is great for stock twins but for singles i recommend a haltech :) unless you live in cali by XS then go ahead and get a PFC :D

13BAce 12-27-01 07:54 AM


Originally posted by vosko
the only way to get 1300cc secondaries is to take your 850's out and send them to www.rceng.com to have them bored to 1300cc costs like $150 per injector. i did alot of research. if you are running very large injectors and a large turbo on the east coast you are better with a haltech. there are a large number of very good haltech tuners over here and MANY race cars are running haltechs without blowing engines. this is the whole reasoning i sold apexi pfc and boost kit it would not work the way i wanted it to work. just ask wankawankel. PFC is great for stock twins but for singles i recommend a haltech :) unless you live in cali by XS then go ahead and get a PFC :D
Enlarging injectors isn't really a good idea. You can get brand new 1200 cc ND injectors for about $150-200.

wankawankel 12-27-01 10:01 AM

What's the deal with having your stock injectors bored larger? I've heard about 50 people saying it wasn't a good idea to have them bored out. Is it because they won't work well after the stocks are modified? Do they leak after? I heard that after they are bored out, they work well because their impedence is the same as when they were stock, where as when you change the injectors to a different brand, you have to mess around with the cells in the PFC just to get them flowing correctly. Answers please. Carl...

vosko: wait for the new haltech coming out. It's supposed to be a self adjusting unit. No more dyno required.:eek:

zkeller 12-27-01 11:44 AM

Will the 1200's you are talking about work in the 3rd gen's secondary ports and are they of the same impedance. If so I'll make the change. I was,am, damn nervous about the bored injectors.

vosko 12-27-01 11:52 AM

are you sure those ND are 1200's from the factory? i've never seen brand new ones. i was pretty sure all of those are 850's bored to 1200 or 1300 and you send them back your cores. i could always be wrong. wanka: i already purchased an E6K so i will stick with it unless this new one is alot better.

vosko 12-27-01 11:53 AM


Originally posted by zkeller
Will the 1200's you are talking about work in the 3rd gen's secondary ports and are they of the same impedance. If so I'll make the change. I was,am, damn nervous about the bored injectors.
many people on the forum are running bored out injectors with no problems. rc engineering has done this to many many injectors.

zkellerATwork 12-27-01 01:24 PM

Vosko,

I guess you're right. You only hear of the bad experiences.

Jedon 12-27-01 01:51 PM

I'm going to need injectors for my new single setup, shooting for ~450RWHP.
I have a PowerFC, I'll put my 850's into the primary location by filing using washers, what would be the most cost effective way to put larger injectors in the secondary location?
Thanx!
-Jedon

zkeller 12-27-01 01:55 PM

Jedon,

Your question is what this post is about. The cost effective way is to send your 850's to RC or to Jason and get them oversized. Keep the 550's in the primary. You will also need to up the fuel pump. I went with the $1,100.00 1600cc fuel kit from rx7.com but am rethinking.

vosko 12-27-01 02:09 PM

zkeller hit the nail on the head :) take your 550's and get them bored to 850's then get your 850's bored to 1300's and you will have more than enough fuel for 450rwhp :)

Jedon 12-27-01 02:42 PM

I have an extra set of 850's so I was thinking of using those as primaries and getting my other 850's bored to 1300. Is this the cheapest workable solution?

zkeller 12-27-01 02:46 PM

A couple of replies ago someone mentioned new 1200's are available. I PMed him to get more info.

wankawankel 12-27-01 02:49 PM

How about we all keep the 1600cc kit and sell the PFC's to the twin turbo kiddies. Let's do wheelies with Pepe Loco. Haltech isn't too far away. Haltech are the arms and legs to the big sinlge set ups. The PFC seems to be only a crutch.:eek:

Jedon 12-27-01 03:03 PM

1. Who tunes Haltechs in SoCal?
2. How do I trade to a Haltech from a PowerFC without losing $?

zkeller 12-27-01 03:05 PM

It's not the Haltech that scares me. It's the damn wiring harness!!!!


How much could I get for my PowerFC with Commander and Boost controller kit?

vosko 12-27-01 03:59 PM

i sold my pfc with commander(had like 100miles on it basically new)from srx7 pretuned for $1100 and boost kit(new) for $400. i lost about $350 but its cheaper than a new engine :) you might as well do it right the first time.

Jedon: in cali there are a few tuners i know K2RD can tune it you just have to ask around.

wankawankel 12-27-01 07:33 PM

As far as getting the Haltech installed, you don't have to worry about it. There are Haltech/Rotary tuners everywhere. And for the harness, fu*k that sh*t. People modify the Rx7's for keeps, so forget about the harness. After the Haltech is in, you have no more worries. No more, "can I install this or that and will my computer control it?". There are many people on the forum that will buy our PFC's for less. First of all did you read how many people bought from the group buy section just to save $200 dollars. I'll sell mine for about the same group buy price, with the commander. And I have maps that people haven't even posted up with yet. Try getting that at a discounted group buy price. Just the facts ladies. Vosko is the first to admit the limitations to the Apexi unit. Limitations to only us. (FD's with MONSTER turbo set ups)

zkeller 12-27-01 07:45 PM

FC's on the Parts Trader!!!!!!!!!! haltech time!!!!!!!!!


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