So wut i want to know is, is it possible to fit a 924 fi unit on a 914. i know the engines are different layouts but is it possible to come up with something that works and works better than the stock 914 injection systems. or has it already been tried and failed

Why bother? The Audi/VW system sucked ass. It would not be an upgrade.

Isn't the 924 an L jet system? I know the 944T is L jet. So, if so, yes it would be simular, but you probably be into a megasquirt system to control in place of the ECU, unless a 1.8 ECU would work.

Nah the 924 used some version Kjet/CIS.

why bother!

if you are going throught the trouble of a F.I. retrofit, look into an aftermarket system.

They are waaaaaaaaaayyyyyyyy more tunable and give you tons more options

id probably just stick to the stock system, i couldnt imagine
too much of a hp gain or anything like that on a stock engine
plus if you have problems later, there is a lot of knowledge and
experience from the guys here to help.

so were would i find an aftermarket fi and how much do they run for? are the reilable?

Megasquirt or SDS systems are the two main systems IIRC.

Megasquirt

SDS

oh im not worried about problems with my stock fi. ive already worked out the bugs in my fi. i want to run a hi performance cam. but the stcok injection wont allow it. and carbs are niether efficient, and they dont get more hp like ppl say they do. so i want fi with a hi performance cam. fi runs cleaner and hotter. hotter is not always better but better in this case. carbs allow the fuel to bead up. the fi adomizes the fuel to allow more of the fuel to be burnt. its a cleaner more powerful burn. plus they r more efficient. my dad ran a 2055cc engine and he got 42 mpg on the freeway. but he ran 205/75/r15s on the rear. so he got higher cruising speeds without compromising effeciency
steven

Ask Jake on the http://forums.aircooledtechnology.com/ about his SDS setup with twin throttle bodies..

or CIS has been used on a few 914's mostly ones running a turbo.

Jake can also sell you a cam for a hipo 2056 but you will need heads and a header to take advantage of it. His 9550 cam will bump you up to 115hp on a 2056 using djet or ljet.

thanks allan. im checking out the megasquirt site right now. its pretty interesting. i migt try this.

MS is cheaper than SDS.

Jake swears by SDS.

Both are good and both work.

MS can be DIY or you can buy an assembled unit. You will need a laptop for tuning and I stronly suggest a 02 sensor.

Just consider the heartache that Dave Hunt went through rebuilding his engine so many times due to Megasquirt problems.

U wouldnt happen to know how much an assembled unit costs would you toon1?
steven

was it problems with his ms or was it him causing the problems.

Dave's motor is completely different.

MS will fuel 700+hp engines with no prob.

BUT who am I to argue.

You can go to DIY auto tune and checkout their assembled units. I think the MS II, which will also control timing is in the $400 range. You can find them used on the MS site or on ebay

You can go with a MSI unit, they are cheaper, and load the MS&Se code. this will also give you timing control but at a lesser resolution(which you willnot need).

Here is my BIASSED .02(since I own an MS)

MS is just fine and don't be afraid of it. it works and works good. SDS is good, Jake does prefere it.

MS is about 1/3 the cost.

I have looked at the specs. on both units and, for the life of me cannot see the difference.

It has been said that MS had too many bells an whistles It does have alot avail. but for a TIV it's basic.

SDS has a 16x16 fuel table, there is 16x16 avail. for MS also but MS primarily uses a 12x12.

You can use the same sensors for both ,ALTHOUGH, MS has the ability to use the air cooled sensors with easy therm.

SDS had limited info about their unit on it's site BUT from what I've heard has great cust. service.

MS has a lot of info on their unit and has a website forum to support it

It comes down to this........... do the research on both and decide what are YOU comfy with?

thanks toon1. ill look into both. but im on a tight budget so i think ill ultimately go with the ms. wut program do i use to tune the unit or does it come with supportive software? thanks for the help.

if a carb and the engine is set up correctly it will make just as much if not more power than efi efficiently.

youd have to have a hot ignition system to go with the carbs. but with properly tuned runners and heads as wells as correct venturis and jets you will make clean snappy power with carbs. you might not have the "42 mpg" that you claim but you will be high to mid 20's without a doubt.

if you ran a hot ignition you could lean out the mix slightly the only thing to watch would be head temp.

carbs are a great option if you know the theory they operate on, can think through the diagnostics, and know all the circuits.
the only drawback would be that altitude changes dont treat carbs well.

thanks shaggy. i plan on sticking with the fi even if it is the stock fi. thats all ive know. my brother has a 72 teener with 40 idas i think. and it didnt perform as well. and they were quirky. i havent had hardly any experience with carbs.
my dad has tought me how the d-jet works how to install and tune it. and thats wut im comfortable with. carbs are simple tho. i just like the idea of fi. and plus i do drive the mountains once or twice a month. breckinridge road in bak cali mainly. i drive that road enough to make sure i stick with fi. thanks for the input.
steven

carbs dont agree with stock efi cam.
that might be why he didnt have good success.

and to change the cam is kinda a big deal.

stock d jet is a very good system.
you can only manipulate so much fuel wise but you have to remember not only to change how it inhales but how it exhales.
stock exhaust is very restrictive and a correctly built header will make more difference than just about anything for the money.

if you really want performance get a 6.
dont get my wrong, a built 4 kicks ass and raby is a genius with these engines, but since working at a porsche shop i have come to realize that the 6 is the way to go. and if you really wanna go get a 6 built by a professional.

Piece of

ive already changed out the old exhuast. im running a dual exhaust like they do on the sixes it sounds good. and is deffinetly not restrictive. i took the shot headers of a 75 and welded 3in cherry bommpers on them. they may not have enough back pressur at the lower end but then engine really starts pulling between 3600 and 6000rpm. the power band is between 4800 and 6000. being that im running the stock djet brain it has the rev limiter. so idk wut its like after 6000rpm. and this is on a 1910cc type 4. my dad and i r building tuned intakes for it also. so it should really pick up in the mid to high r's.id love a six but cant afford it. true my bro didnt chang out the cam. and besides im not done screwing around with these little 4s yet. besides the fact that im only 17 and i prolly cant handle that much power yet. but others i dream of sixes. thats my ultimate goal for my car is to have. a six conversion. id love to have the 78 911 turbo 3.0l engine. but thats not going to happen at least for a while.
steven

yea i never really care for the 924. and to think those pos' replace the 914 wut a shame thats total was porsche thinking?

"Piledriver" over on the Shoptalkforums (dot-com!) "Type 4um" has used Rabbit CIS on a 914 motor. He likes it, a lot. Jake put CIS on a Bus motor, and was happy with it.

It can be made to work, and you can score a complete system for cheap from the junkyard. Just make sure the fuel distributor is nice and clean...

--DD

The main problem people have with an aftermarket EFI, is with hot cams. When you have a hot cam, and are using a manifold pressure based system, you will get poor results. The manifold pressure sensor "sees" the lumps on the cam, and gets a bit confused. There are a few ways to deal with this. You can add a vacuum buffer to help smooth out the lumps. Another way is to program the EFI to ignore the manifold pressure under certain circumstances. Yet another way is to use a Mass Air Flow sensor to read the amount of air coming in. The L-jet and CIS are both MAF based systems. The third option is to use a combination of MAF, manifold pressure and throttle position. The Megasquirt II has the ability of doing all three.

CIS from any VW GTI is a very good reliable economical conversion as a replacement of the stock system just ask EvilEd.

Get a copy of Excellence June 02' 4 page article on the conversion to CIS and Turbo.

I own the car now and is is very very reliable, I recently upgraded the fuel distributor to a brand new Euro version (flows more fuel ) and swapped the turbo with a brand new K 26 that was a Audi 5000S application.

Spoken like someone who hasn't taken the time to learn and understand how CIS works. Simple, seriously wide power band, easy to maintain, easy to troubleshoot. CIS-E is even better. As with most factory installed FI systems, you can't run much in the way of a hotter cam, though. The Cap'n

It never ceases to amaze me how many people will bash a car over what they have been told/read having never owned said car. 924 a POS huh? Why is that? Because it was a great handling, cheap, 4 cylinder bastard child of Porsche ????? Yeah your 914 is all high and mighty though Look I've owned BOTH as well as a 944 an early 911 and a 356. NONE of them are POS cars. They ALL have their weak points and quite honestly the 82 924 I had was a HELL of a fun car. Yeah it is severly underpowerd but I had that car sideways at 35 mph, dropped a gear, floored it, and strightend it back out. Poly bushings made a major difference but for a daily driver the transmitted noise was no bueno. Bash all you want, you will still look like a bufoon to those who KNOW the car. BTW CIS is a no-brainer. It's like ANY system, learn it and learn to adjust it properly. I NEVER had a CIS car leave me stranded..........

true. but its not a true porsche unless its mid or rear engine. and its not a classic porsche unless its aircooled.its just the black sheep of porsches family.
steven