How to modify 850cc to fit primary.
#1
How to modify 850cc to fit primary.
I'm putting a new secondary fuel rail with 1600cc.. was wondering how I can get my stock 850cc's to fit my primary.. I've heard you just add an extra oring near the bottom of the injector.. is that all?
thanks in advance..
thanks in advance..
#4
Go to this site and it will tell you everything you will need to know.
http://www.wvinter.net/~flanham/wlan...el/850pri.html
I'm planning on doing it to smooth out the transition between the two and having the ability to run more fuel could never hurt. Just my 2 cents.
http://www.wvinter.net/~flanham/wlan...el/850pri.html
I'm planning on doing it to smooth out the transition between the two and having the ability to run more fuel could never hurt. Just my 2 cents.
#7
I just put the 850s in the primary spot. What i did was just grinded the top of the rail off a bit. My onyl concern is that the lower oring isnt in the right place. ON the 550s the lower oring sits in the middle of the taper, and with the grinded down priamry rail and the 850s in the spot it at the top of the taper on the rail. Is this how it is for everone? Or do i need to grind away some more? But the bottom cap can be put on snug with just the original oring, yet you can move the gromet down a bit to make room for another oring to make them long, and still have the gromet snug! So it seems like they are many different variables in this.
Marc
Marc
Trending Topics
#10
It seals fine after milling the rail. I even tested it with the rails hooked up but not mounted on the motor - no leaks.
My bigger concern with this mod was the injector pintle being recessed with 850's and not flush like the 550's. I was afraid the fuel would spray in a cone and hit the side of the rail then drip into the motor instead of atomizing in a mist. I had my new and old injectors flowed by Kinsler, the 550's have more of a cone pattern while the 850's have more of a straight stream.
After my leak test with the rails out, I pulsed the injectors to observe the spray pattern coming out of the rails. With the straight stream most of it comes out as a mist but there is a little bit that hits the sides and drips.
RP and others report no problems running 850 primary while some say it runs too rich at idle. This leads me to believe its in the tuning. There have been many threads on here and in the datalogit mailing list but no conclusions.
I've only tested but not run my car with its new motor so I can't say how it operates yet.
Jack
My bigger concern with this mod was the injector pintle being recessed with 850's and not flush like the 550's. I was afraid the fuel would spray in a cone and hit the side of the rail then drip into the motor instead of atomizing in a mist. I had my new and old injectors flowed by Kinsler, the 550's have more of a cone pattern while the 850's have more of a straight stream.
After my leak test with the rails out, I pulsed the injectors to observe the spray pattern coming out of the rails. With the straight stream most of it comes out as a mist but there is a little bit that hits the sides and drips.
RP and others report no problems running 850 primary while some say it runs too rich at idle. This leads me to believe its in the tuning. There have been many threads on here and in the datalogit mailing list but no conclusions.
I've only tested but not run my car with its new motor so I can't say how it operates yet.
Jack
#15
Guys, the link above describes perfectly what needs to be done. No milling of the rail is required. I added the extra rubber grommit and that's it. That's all you need. I jumped the pumps wide open at 12V (dual walboros) and cranked it towards nearly 100psi. No leaks at all.
#18
The link below doesn't work anymore:
http://www.wvinter.net/~flanham/wla...uel/850pri.html
Does anyone have another link, or can post the procedure ?
I don't want to mill off 1/8-inch if I don't have to.
TIA,
:-) neil
http://www.wvinter.net/~flanham/wla...uel/850pri.html
Does anyone have another link, or can post the procedure ?
I don't want to mill off 1/8-inch if I don't have to.
TIA,
:-) neil
#20
FWIW, after reading the possible failures of having double O-rings, I just had my local machine shop mill off 1/8-inch off the top of the primary rail.
I installed cleaned & matched injectors with new VITON O-rings care of Witch Hunter.
I made the appropriate changes to my PFC, and she fired right up. Now for a tuning session with Steve Kan!
:-) neil
I installed cleaned & matched injectors with new VITON O-rings care of Witch Hunter.
I made the appropriate changes to my PFC, and she fired right up. Now for a tuning session with Steve Kan!
:-) neil
#21
Speed Mach Go Go Go
iTrader: (2)
Joined: Oct 2001
Posts: 4,772
Likes: 2
From: My 350Z Roadster kicks my RX7's butt
I had the top milled and the cap fit fine. I also milled down the inside cone part so the injector would sit lower. The pintle is alot lower and I feel safer then with double o-rings.
#22
What is the best way? I'm currently in the process of doing this? At first I was going to do the double oring and leave it at that, but my friend didn't feel safe with doing that. Do I just mill the top of the primary rail by 1/8 inch instead? I wish I could view this old link http://www.wvinter.net/~flanham/wlan...el/850pri.html but it doesn't work. Any suggestions would be greatly appreciated.
#24
I just doubled the o-rings and stuck them in. It works for the most part, but I do suspect a leak as I am getting poor tip-in despite what I do with the pfc.
Having said that, the very next thing I'm doing is having the primary rail modified to properly fit the 850's.
Having said that, the very next thing I'm doing is having the primary rail modified to properly fit the 850's.