Switching 550s for 850s what needs to be done??
 

I have a pfc with single turbo
I want to switch over to these injectors

I need bigger o rings or to have my primary rail tapped but what exact size O rings and what do I do with the rail? I want no leaks!!

Also dont I have to change somestuff through the commander or datalogit? I thought steve kan told me to switch the 550 volts to .68 or something is that right?

Will I have to retune the car or will it drive fine after?

thanks

Spoolup had some pics of the 850s on the primary rail.

I believe the rail was shaved/milled 0.125 or you could add the o-ring

threre was a thread in the PFC section on hte settings for the 850s

it'll drive alright but you'll be running richer than normal. for optimum power a retune would be neccessary.

Or you could lean it out yourself but then you're playing with a loaded gun.

edit: Oh, it's SurgeMonster. Hey man, how's it going? you get your new engine back together?

850cc
 

Just had mine done weds at KDR. I bought new injectors from the RX7 Store, and they shipped them to RC to be bored from 550 to 850. Dave says they have experienced leaking when using 850 secondaries in the primary position, so I went this route

books thanks

150FC I am going NA this weekend!! I examined my turbo and it wasnt damaged somehow what a miracle. So Now I am doing a custom NA setup LOL so that I can drive around my car without damaging the turbo and who cares if the engine totally blows up right then ill just get a reman...I dont want to rebuild a 52k mile old engine any way.

mahjik thanks I had already seen that. It doesnt say what size o rings he said he just went and asked some company for them. Also he says they experienced no leaking but Ive heard that there was leaking from a lot of people so I want to know what is true.

rallimike thanks, can you ask dave which method they were using when they were getting the leaking?

From personal experience, you can make the stock 850cc secondary's fit inside the 550cc primary injector seat. You'll need to shave off the top off the seat appx 2mm so that the 850cc injectors will not leak. HOWEVER, your idle will suffer because the 850cc injectors sit higher in the seat and do not sit flush like the 550cc injectors. If you bore out the 550cc to 850cc injectors, your idle will probably be better since the injector sits where it's supposed to be unlike the 850cc secondary injector. I'm running 550cc in the primary. I'm looking into buying a true 850cc secondary seat in the future.

It idled fine when I drove it home. Of course, it was snowing and I was scared to death, so I wasn't paying much attention to the idle :)

But you have the 850cc injectors that fit properly vs. the 850cc stock secondary's made to fit into the primary fuel rail. How much did it cost to get them bored out?

I think it was $175 each

is it a fact that im going to just run a little rich?

so I drop these in with the new o rings and change the one setting on the pfc and im good to go?? It will run rich not lean right? the computer will know how to control the 850s just like it did the 550s?

thanks team

I just did put 850s in my primary slots, and it works fine, i just used some o-rings. no leakin so far.

http://www.newwave.net/~flanham/wlan...el/850pri.html

Like the link above, and ghost, I'm running 0 rings only. So far so good. :) CJ

just dont watch those injectors when your takin them out.....lol....OUCH!

anyone else got anything to add?

like what specifically I need to do in the PFC?

and can everyone confirm I dont need a retune? ill run rich if anything for sure?

thanks

You do need a retune. Too much fuel can also be a problem:

On pages 25 and 26 of the FC-Commander Instruction Manual are details on exactly how to change the settings. The directions are fairly clear and have an example.