I've noticed there is a very different part number for the latter E21 as opposed to the eary ones. Is there that big of a difference that either can't be used on BOTH M10's? I guess what I'm asking if if the injectors 0 437 502 006 can be used on my 1978 2.0. Anyone know???

Thanks!

From what i have heard, the early injectors flow a bit more because of the .2 Liters of extra displacement.

Anybody know if the "early" injectors pop right in?

With the 2.0 "air flap" being bigger, does it make any sense to swap those injectors and the 2.0 air meter on to a 1.8, or, is it just a waste of time since the stock CIS/injectors would deliver enough fuel?

From previous experience on an old 280Z a larger air meter and the inlet to the manifold matching made a big difference with the car too rich to pass emissions at idle (low end the change nothing special, but with air hitting the intake at speed it flew!)

Once I find an old 2.0 "air meter" I'd like to throw it on there; a previous post said there was a difference to be had.

This post on the injectors made me wonder if I'd want to do them as well, on the theory that with the 280 I wasn't getting enough gas with the extra airflow, and this would be a same/same type deal.....

Thanks.

I just got a 2.0 air meter off of ebay. the swap is pretty simple, but you have to seperate the halves of the AFM. The older style meter was actually bolted to the air filter box. I have yet to install it in my car, but i would like to get my hands on some early injectors if they actually do fit.

seems like this would be a worthwhile swap.

The difference between the two injectors is their length, necessitated by the different heads they go in. They flow the same, open at the same pressures, etc.

I have heard from a local E21 guy that is much more curious than I of the early AFM swap. Do this and let us know how it turns out! He swears he gets more umph, but I like to hear it from more than one guy before I jump in to try it...

John
83 320iS

I know a guy that is running a 2.0L air meter on a 1.8L engine. I don't know what injectors he is using. He says it makes more power.

ken

Ken,

Does the fella running the 2.0 air meter on the 1.8 "run out of gas" on the top of the rpm band?

I've heard it said that CIS will "adjust" for a fair amount of power, but I don't know how much. I know in a post somewhere you said you were leaning out too much on the top end, but I know you were running a bit of a cam, etc... and probably making a lot more than a 1.8 would put out given this mild configuration change.

Your inputs are always appreciated sir!

Thanks.

So I wonder if they are also using the 2.0L fuel dizzy also, or the 1.8L? I know the flapper valve is bigger on the 2.0L...I dont know if the dizzy flows different, but there is an early and late fuel dizzy also...

John

I think he's also running the 2.0L fuel distributor, he seems to like it a lot and has not mentioned any lean out issues.

My '82 used to go lean over 5500rpm before I switched to EFI a couple years ago... I'm pretty sure my CIS had some issues-the cam should not cause that. It came down to 1. mess with the CIS and make it run right and get GOOD power or 2. convert to programable EFI and get GREAT power... easy choice for me. My stock CIS '78 has an idle hunt issue occasionally but I'm not sweating that at all.

ken

Well then, I think I'll start looking for a 2.0 air meter, and perhaps look into how much difference there is between the two FD's.

Thanks guys.

OK, so eliminating the discussion about swaps to different heads and blocks and dizzies and air flappers....I'm trying to focus on a 2.0 block with a 2.0 head with a 2.0 dizzy and a 2.0 AFM with 1.8 injectors. I'm hearing they are only longer. Ok, now that point hs been met but does that in ANY way affect performance?

No, it doesn't affect performance. The 2.0 injectors are longer because they mount in the manifold, not in the head like the 1.8's. CIS Injectors are not usually the bottleneck in the system, they will dump as much as you can give em. The bottle neck is probably going to be the fuel pump or the fuel distributor.

Keep in mind that on the 1.8 system, that's going to be upwards of 170+ hp before you run out of fuel flow (I recall reading up to 190hp somewhere, but I have no proof or evidence of that). The 80mm air flow meter will definately be less of a restriction at higher rpms and you should be able to feel that extra breath on the butt dyno. I hear VW guys do a similar swap.

I think the 1.8 FD will work fine with the 80mm lift plate, on a healthy system it can support over 170 hp. It takes a LOT to get an m10 up to that level NA. If you swap to the 2.0 FD, you'll have to figure out how to do away with the frequency valve which dumps into the fuel return line.

My lucky day, Mr. Cook has already looked into the FD question.

Thank you, that's great info. I appreciate you taking the time to post.

I have done SEVERAL of the afm swaps on VWs, using the same fuel dizzy most of the time.

The problem is that the tiny 60mm dia plate really chokes the flow down at mid to higher rpms. It is a very easy to feel difference on a mild 1.8 VW 8 valve engine - similar in hp & torque to the M10.

Ken makes a valid point about EFI being hugely better than CIS, but for a $10 mod, it is worth its weight in gold. Especially if you are modding your later model E21 and keeping the CIS.

So as it sits no one yet has been able to say that NO it wont work. I'd hate to just slap these in as the injector ports are NOT readily accessible!! On the 2.0 they are UNDER the intake runners. Definitely NOT an easy task without some tremendous effort!..

I bet a 292 cam, 80mm afm, fatty throttle body, kdanielson header and 2.25" exhaust would be a very nice combo for a mild to medium m10 if you wanted to stay w/ k-jet.

I guess I'll just have to settle for my 80mm 924 turbo afm, 65mm 528 throttle body and 2.5" side exit exhaust :(

I bet a 292 cam, 80mm afm, fatty throttle body, kdanielson header and 2.25" exhaust would be a very nice combo for a mild to medium m10 if you wanted to stay w/ k-jet.

I guess I'll just have to settle for my 80mm 924 turbo afm, 65mm 528 throttle body and 2.5" side exit exhaust :(

Yeah that and a relentless hair dyer attached to your manifold :shifty

So as it sits no one yet has been able to say that NO it wont work. I'd hate to just slap these in as the injector ports are NOT readily accessible!! On the 2.0 they are UNDER the intake runners. Definitely NOT an easy task without some tremendous effort!..

Ken, stick with the right injectors. I dont really recall which is longer, early or late. But Im just careful that way...you may find they actually do work ok.

John