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K-jet on newer heads?

DaRiceRipper

New member
Joined
Nov 20, 2002
Location
North Jerzy
Hey guys i wana swap a ported and polished head from my turboed B23 on to my B21ft.
And i wana know if i can drill/tap the head to except the K-jet injector lines.
And will this effect the lower compression level of my B21ft.
 
DaRiceRipper said:
Hey guys i wana swap a ported and polished head from my turboed B23 on to my B21ft.
And i wana know if i can drill/tap the head to except the K-jet injector lines.
And will this effect the lower compression level of my B21ft.

Yes you can. Take the non-tapped head and a tapped head to your local machine shop. They shouldn't have any problems.

David
 
You wont effect compression ratio at all. K-Jet is NOT NOT NOT direct injection. The injectors push into the intake port, not the combustion chamber. There are plenty of people who adapted injector bungholes for the EFI manifold and put the K-Jet injectors there. No head drilling required. There are pages but I'm too lazy to look for them and link them.
 
You sure can. My daily driver has such a setup, although I?m using a stock 530 head. The machine shops would have wanted 300$ to make and tap the holes, but I lucked out and a friend did them for me for a very affordable price. This friend of mine had access to all the necessary equipment, so it?s not something the average gearhead can do in the home garage, though 8).
 
which way you go re injector system and control is your choice....

....but do not make the common error and disparage the K-jet sys just because it is not "electronic"....or some other fad-of-the-day term...

....injector location and spray pattern and timing of the injection sprays are areas of discussion that has been essentially glossed over and ignored....here, anyway....

...as has been the advantages of the continuous injection facet of the K-jet system....

the location of the k-jet injectors in the head are for a reason....better delivery...

the continuous injection also has advantages over the timed, pulsed squirts.....also better delivery; and the effects on the CC mixture map vs a pulsed injector squirt's effects on the mix map have been analyzed.....the results of those studies would suggest that the continuous injection system has certain inherent advantages over a pulsed system that warrant careful consideration before throwing the baby out with the bath water...

...no argument will be given by myself to say that the B21FT K-jet is the ultimate anything.....but it works pretty d##n good, and the way it works has its very good points.....

....again, it is your choice...your $$.....but I would suggest caution before discarding a very good system based on some minor difficulties in fitment...
 
It works amazingly well at the job it was designed to do within the environment it was made to do it in for sure, but there is a relativley small window in which it is "capable"- beyond which either a completely new distributor, or other additional fuel enrichment systems need to be introduced, and it is downhill from there- just depends on what his ultimate goals are.

I'd also say that "electronic" fuel injection has stood the test of time and is a great deal more valid than just a "fad of the day", I think it deserves a little more credit than that, at least as a whole.
A few people are working on piggyback systems to add additional electronic injectors into the mix to work with the k jet, if these work well then that definitely breathes a bit of new life into the system, although definitely still not the cleanest solution...
Just some thoughts.
 
Im guessing i should have been more detailed in why i posted this thread.
sorry guys



My original thought was to keep the K-jet in the head so an extra set of injectors could be placed in the newwer intake manifold.
Then i was thinking of adding the megasquirt to control the extra 4 injectors, but after reading alot more about megasquirt i have relized that with the megasquirt thier would no longer be a need for the K-jet.
My reason for all this is running my wagon at 15-16 psi. Now from what ive read on the board and in written articals is anything above 12-13 psi without any problems would require more fuel. So i went to the LOW COST build up for the b21ft and saw what was wrote up about adding the 4 injectors started the thought that has ended me to the low cost build up of megasquirt.
 
I used to be a big advocate of Kjet but that was only because a decent EMS was 3 times more than I paid for both my cars. Enter Megasquirt. Bye Bye Kjet. Kjet does work and stealth is right about the injector placement and the benefits of having the high pressure nozzles close to the intake valves. The fact remains, though, that you can get twice as much HP from an EFI setup with a lot less work. And for the cost (which is now well under $500) an EMS is my replacement for the good old Kjet that I defended for years.
 
Cappy...I was dissing EFI, but not because it's bad....

Mike...I appreciate your choice to go EFI...

...my slap at EFI vs K-jet was meant more to remind people that K-jet does have it's strong points....but, yeah, I was being a bit sarcastic...

...for those who have opted to retain K-jet on their turbo motors and to add an AIC to control a set of electric injectors to add extra fuel during high boost, I would suggest that their choice was a good one, even though it may have been made for reasons other than the following:

...the location of the K-jet injectors in the intake runner of the cylinder head just in front of the intake valve is an excellent location....it puts the fuel spray right where it needs to be...

...the fact that it is a continuous injection spray does affect the mixture richness when the intake valve opens....the mix is richer, and helps cool the CC when initially drawn in...which means that the heat absorbed by this "rich" mix also helps the atomization of the fuel, promoting the homogenation of the air/fuel mix....

...the continuous injection spray also helps keep the incoming mix more consistent.....with a pulsed injection spray, the last part of the incoming mix tends to be leaner than the beginning or middle portions of the incoming mix...this results in varying rich and lean pockets of the incoming air/fuel charge, affecting the homogenation of the air/fuel mix....which means that the swirl and tumble and squish have to work harder to make sure the mix is really stirred up well to try to eliminate the lean pockets....

...this variation of the uniformity of the incoming air/fuel mix with electric solenoid injectors can be minimized if the electric injectors are pulsed in a synchronized manner related to the intake valve cycle, or by utilizing multiple pulses per intake valve cycle...whether or not the aftermarket EFI controllers are programmed to synch the pulses to the intake valve cycle to maximize the uniformity of the incoming mix, or utilize the multiple pulses per cycle approach, I have seen no documentation confirming, denying, verifying, explaining, or specifying which or what type of pulse synch or frequency is employed....I am sure that the info is available, or should be; and would ask that anyone who has that info on the system they use, to share it here...

is this a "splitting of fine hairs"?.....perhaps....but if a person has a performance problem such as detonation or misfire under load that is NOT ignition system related, I would suggest that how well and where the fuel injection system delivers that fuel and when it delivers that fuel 'may' be part of that person's problem....

but I have digressed....back to the K-jet with AIC choice advantages....

...those using K-jet/AIC have a very good fuel delivery system [for the reasons already given; plus the durability and reliability factors of the K-jet system are well established] that supplies what they need for 99+% of the time....and when they need that little bit extra, it is available via the AIC/extra injectors....

...in other words, daily driving is handled by a durable, reliable, serviceable system; and the emergency "wartime" power extra fuel needs are supplied by a stand alone, non-interfering system, which, if it fails, they can still drive...kind of a "best of both worlds" approach....

For those who have opted to go away from K-jet, I can and do appreciate their choice....and meant no disrespect for that choice....I just wanted to let those who kept their K-jet, and opted for an AIC, know that their choice has its merits as well...
 
I agree. Nothing wrong with Kjet, untill the economics of the maintainance prohibits it. I'm POOR! I can't afford a new warm up reg, let alone a new distributor. I have my megasquirts ready to install but I find myself in a similar position to the latest 242ti owner to finally make the switch. I am waiting for the Kjet to completely fail so that I am forced to take the time to do the swap. :oops: I know Jordan is rolling his eyes right now! :roll:
 
Oh I am... Just get it in there already! You need to do it now, so you have time to tune. Not that you have a deadline

:roll: :roll:

Jordan
 
speaking of tuning, how's yours running? Have you talked to that guy out west with the 242ti? He's tuning his. I think he just got it hooked up last week.
 
Tuning is going good... Getting terrible milage, but thats because I spend most of my time in boost, trying to tune it.

Tuning has been put off for a while until gas prices drop, 88 cents a liter for regular right now. Havn't looked at premium, scared to.

Who is this that is up and running in the west? I am in the west, I only know of one other person out here with a volvo up and running, and he just moved to Arizona.

Jordan
 
Domingo Verdin
Tucson, AZ
82 Volvo 240 Turbo

Sounds like your compadre? Says he's having a little trouble with the upper end of the map.
I still want a data log to look at. Remember when I was going to tune my car and give you my map. :oops:
Anyway, my car is starting to flood pretty bad after a hot soak so it's getting close to swap time. Almost left me stranded the other day :rant: I was not happy! S'pose that's what I get. :? Neglect your 20 year old Kjet
and you're bound to get stuck.
 
Nope, thats not him. But I have talked to that guy. This guy posts here everyonce and a while. Jesse Obuzz... His brother in law is also looking at MS his Turbo car..... He was on here a few times also.

I am also having a hard time with the upper rpm map. It isn't indicating lean... But it stumbles really bad in the upper rpm band either increasing or decreasing the fuel values.

Gonna go out tommorow and play some more.

You should be able to get running in a day. Once you actually start the swap that is.

Go for it man... Its not difficult. Our maps will get you running, then you can tune from there

Jordan
 
Last I heard, Jesse was selling his car to his sister or something, and he is building a racecar! Should be interesting. I loved his 245... It looked so good! I dunno if you ever saw it in person Jordan, but it was really well done. The ultimate junkyard assembly!
 
He has been talking about selling it a lot. and I think it was his sisters husband he was gonna sell it to. I never saw it in person, but I saw quite a few pictures. I was very impressed. I was really impressed with how much he had actually spent on it and what he got. Was the paint job nice? Couldn't really tell by the pictures

Jordan
 
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