M10 rebuild advice please (Upgrading 1.8L to 2.0L questions)

[amarino]

Let me start off by saying that I know little about engines and I just learn as I go along. Feel free to correct me.

I am starting to plan out my M10 build and I have some questions/clarification that I can't seem to find an answer for. I've pretty much made up my mind that I want to go with a 2.0L. So my question is if all I need to do it find a 2.0L M10 crank, be it from a 2002 or early E21?

From reading the FAQ/DIY it seems like the connecting rods are the same in the 1.8L and 2.0L M10's, so I should be able to reuse mine, correct?

I also am going to need new rod/main bearings correct?

Next up is the pistons. I already know that I shouldn't/can't reuse the 1.8L pistons in the 2.0L crank. I'm leaning heavily towards Ireland Engineering's "CAST PISTONS FOR E21 HEAD - 90MM BORE, 9.5:1 CR" after I saw that they include the pins, clips, and rings. http://www.iemotorsport.com/bmw/2002...0cast-E21.html Does anybody have any experience with them?

To put this in perspective, my plans for the top end are an Ireland Engineering reground 284 Cam with Heavy Duty Valve Springs, Heavy Duty Rocker Arms and Rocker Arm Locks. I've had bad experiences with Febi rocker arms in my current E21 where they break at the eccentrics.
Reground Cam: http://www.iemotorsport.com/bmw/2002...amregrind.html
Heavy Duty Rockers: http://www.iemotorsport.com/bmw/2002.../02rarmHD.html
Oversize Eccentrics: http://www.iemotorsport.com/bmw/2002...02rarmadj.html
Rocker Arm Locks: http://www.iemotorsport.com/bmw/2002...ockerlock.html
Rocker Arm Hardware: http://www.iemotorsport.com/bmw/2002...0rkrhrdwr.html

I am going to get a 2.0L AFM and I already have a short ram K&N intake. As for the exhaust I am looking for some nice headers (Let me know what you have/where I can find some) and plan on buying an exhaust set from OLD MAN.

The car will mainly be a DD that I plan on tracking/autoX on the weekends.

[Christo19]

As far as i know you seem to be correct with your thinking on that all, it sounds like a really solid plan! All that is going to make your car a lot of fun

[autox320]

I'm rusty but feel like jumping in here for a min.

First question you need to ask is if your planning on using a full 2.0 setup with "e21 head" or a 2.0 bottom with newer "1.8i head". Makes a difference on which pistons you can get.
If all 2.0 parts you can look at maxsil pistons (bimmerworld sells them). Some have found the maxsil comes in high compression than stock ratios. Especially the 1.8L pistons they are 9.0:1 instead of 8.8. This will a milled head can get up there. IE pistons are the only ones I know of though for 2L bottom and 1.8i head. Keeps the wrist pin location correct for the stroke.

So my question is if all I need to do it find a 2.0L M10 crank, be it from a 2002 or early E21?

Any early 2.0L M10 crank.

From reading the FAQ/DIY it seems like the connecting rods are the same in the 1.8L and 2.0L M10's, so I should be able to reuse mine, correct?

yes rods are all the same

I also am going to need new rod/main bearings correct?

sure, I use bimmerparts.com but there are plenty of sources

Next up is the pistons. I already know that I shouldn't/can't reuse the 1.8L pistons in the 2.0L crank. I'm leaning heavily towards Ireland Engineering's "CAST PISTONS FOR E21 HEAD - 90MM BORE, 9.5:1 CR" after I saw that they include the pins, clips, and rings. http://www.iemotorsport.com/bmw/2002...0cast-E21.html Does anybody have any experience with them?

The ie pistons are heavy but one of the least expensive options. 90mm bore is an excellent choice to keep meat between cylinders. 9.5:1 will be a good match for the 284/288 cams IMO.

To put this in perspective, my plans for the top end are an Ireland Engineering reground 284 Cam with Heavy Duty Valve Springs, Heavy Duty Rocker Arms and Rocker Arm Locks. I've had bad experiences with Febi rocker arms in my current E21 where they break at the eccentrics.
Reground Cam: http://www.iemotorsport.com/bmw/2002...amregrind.html
Heavy Duty Rockers: http://www.iemotorsport.com/bmw/2002.../02rarmHD.html
Oversize Eccentrics: http://www.iemotorsport.com/bmw/2002...02rarmadj.html
Rocker Arm Locks: http://www.iemotorsport.com/bmw/2002...ockerlock.html
Rocker Arm Hardware: http://www.iemotorsport.com/bmw/2002...0rkrhrdwr.html

Solid plan, but I'll throw in an alternate. Not to cut corners just from past exp. Racetep/topend performance 288 cam. Larger eccentrics not needed. Locks you can search there is a mcmaster carr shaft collar thats less expensive and what a lot of folks run for some reason
The rockers you can find used 77-79 2.0 rockers (beefier). Used ones are heat cycled, but if you like can probably find new ones.
For the rocker hardware the only part that we used to upgrade was the nuts themselves. They are soft so finding a higher harness set of nuts kept them from slipping and breaking. Also removed the washer just under the nut gave it more bite without having to run it so tight. Over tighten and it stresses the rocker end also can cause it to snap.

I am going to get a 2.0L AFM and I already have a short ram K&N intake. As for the exhaust I am looking for some nice headers (Let me know what you have/where I can find some) and plan on buying an exhaust set from OLD MAN.

maybe thought of carb? I'm a big fan of the 38/38 weber(webercarbsdirect.com), but there are plenty of other options.

The car will mainly be a DD that I plan on tracking/autoX on the weekends.

Depending on how much it matters can choose fueling wisely. I DD'd mine but not a average DD person. If carb is a choice you could go with a 32/36 thats drilled out from racetep. They have a better chance at keeping the bowl full during hard G's. Of course a 38/38 can be setup for street but I had some issues sucking in rain on open filters lol. It can be done though.

[Layne]

First question you need to ask is if your planning on using a full 2.0 setup with "e21 head" or a 2.0 bottom with newer "1.8i head". Makes a difference on which pistons you can get.

Was going to say this. When IE says "E21 head", they do not mean a head which is found on an E21, they mean a head with the "E21" casting mark. These are very hard to find without cracks, so I would go with the 1.8i head (which you already have).

The rocker locks are just 5/8" shaft collars. You can buy the split aluminum ones just like everyone sells, or you can use steel to save money. McMaster has both (and many more).

[amarino]

I'm rusty but feel like jumping in here for a min.

First question you need to ask is if your planning on using a full 2.0 setup with "e21 head" or a 2.0 bottom with newer "1.8i head". Makes a difference on which pistons you can get.
If all 2.0 parts you can look at maxsil pistons (bimmerworld sells them). Some have found the maxsil comes in high compression than stock ratios. Especially the 1.8L pistons they are 9.0:1 instead of 8.8. This will a milled head can get up there. IE pistons are the only ones I know of though for 2L bottom and 1.8i head. Keeps the wrist pin location correct for the stroke.

Was going to say this. When IE says "E21 head", they do not mean a head which is found on an E21, they mean a head with the "E21" casting mark. These are very hard to find without cracks, so I would go with the 1.8i head (which you already have).

I did remember reading that, but I forgot, thank you for clarifying. I guess I need to make sure which pistons to use with my 1.8i head.

Also, I thought long and hard about the cam and came to 284 as it was tamer for the street, since that will be my main use.

Carb has also crossed my mind but after spending 3 years learning the ins and outs of K-Jet I felt like sticking with that. I also plan to maybe go Megasquirt sometime in the future. It sounds like a fun project.

[SkiFree]

It's always worth calling IE directly since they'll help put together a list of what you might like and what is overkill.

It doesn't look like you're all that far from Duarte, CA either.

[amarino]

It's always worth calling IE directly since they'll help put together a list of what you might like and what is overkill.

It doesn't look like you're all that far from Duarte, CA either.

Yep that's why I love them. I've done will call on orders and picked up things the same day.

So they do make pistons for the 1.8i head and everything else is the same (CR, size, and price), they just don't have them on the website. He explained that when they cast the pistons, they leave a little extra on the top then machine them to the individual heads. I just need to call and order them.

[autox320]

The 90mm 10.5 version is in my coffee table from IE.
http://forums.bimmerforums.com/forum...1#post25011372

Honestly the machined dome has a hard edge to it. I'd think about rounding it some even if it's with emry or 3m wheel.

[waferman]

Hey, just read this. I decided to stick with stock crank in 2005 when I started my rebuild, so I kept 1.8L crank and used Maxil pistons to great effect. I know that you aren't going that direction, and I wish that I had saved an extra $700 for the TEP short block kit. That will be my next rebuild, but my engine runs really well as it is. What you are doing pretty much mimics TEP's performance engines. 2.0L crank, 9.5:1 pistons, 2.0L AFM, header and head work is what they do to eek out a nice boost. I just need to rebore my block for the pistons, and I already have everything else.

I do want to do one thing first; convert to L-Jet. Should be easier to tune...but I'm thinking that I won't be able to keep my 1.8L intake...more research is needed!

[Layne]

I do want to do one thing first; convert to L-Jet. Should be easier to tune...but I'm thinking that I won't be able to keep my 1.8L intake...more research is needed!

L-jet is not tunable. If you have a stock-ish 1.8, that won't matter though. You do have to switch to an E30 318i manifold. It looks almost identical to what you have though, so the appearance will stay the same.

L-jet starts and idles better than CIS, but it's technically inferior. In fact I dare say it blows. Save up for megasquirt or don't bother with EFI.

[waferman]

Well Layne, while I'm pretty comfortable with CIS, after tearing into my E28 I have to say that I'm tired of tuning the stupid thing (kjet)! If it runs bad, it's a sensor. Bang, new sensor, fixed. I'm thinking that L-Jet would be the same...about the only tune I do that really makes the car scoot is to advance the timing. I think with L-Jet you can still do that?

I'm never going to play with megasquirt- just too much trouble to figure out. A 6cyl 2.5 upgrade would be ideal, but again- too hard to find the right subframe and so many other things that would need to be upgraded. I'd be happy with a smoother running engine...

[SkiFree]

What you are doing pretty much mimics TEP's performance engines. 2.0L crank, 9.5:1 pistons, 2.0L AFM, header and head work is what they do to eek out a nice boost.

I think it mimics ANY decent performance build, don't you?

OP, I know of several 2.0 cranks, but they're all pretty gold plated. I think there was a gentleman in the 2002 section saying something about a 2002 at a P&P nearby.

[waferman]

Yes, this is the best way to put a smile on your face in the E21!

I found a 2.0L crank locally. I'm hoping he takes my offer of $70...

[amarino]

So hdx, Cruz, and OLD MAN were preaching how great and simple carbs are. I still have some time to think but I know that I am going to miss my 25-30 mpg that I am getting now. I know that I am already going to lose some mpg in the 2.0 swap and now more if I do go carb. It sounds like a really good idea, and I'm seriously considering it now.

3 issues I have.
1) Going carb vs K-Jet, will there be a drop in hp and/or torque.
2) How much would it add to my budget for a carb and the conversion. I already have 2 cars worth of K-Jet and 3 years of experience troubleshooting. And to be honest, I've seemed to worked out all of my major issues with my K-Jet system. It's going to almost be a year that I've had a reliable DD that starts up every morning.
3) I have a front strut brace, just curious how much higher, if any, a carb would sit than the stock 1.8L manifold.

[FranzE21]

So hdx, Cruz, and OLD MAN were preaching how great and simple carbs are. I still have some time to think but I know that I am going to miss my 25-30 mpg that I am getting now. I know that I am already going to lose some mpg in the 2.0 swap and now more if I do go carb. It sounds like a really good idea, and I'm seriously considering it now.

3 issues I have.
1) Going carb vs K-Jet, will there be a drop in hp and/or torque.
2) How much would it add to my budget for a carb and the conversion. I already have 2 cars worth of K-Jet and 3 years of experience troubleshooting. And to be honest, I've seemed to worked out all of my major issues with my K-Jet system. It's going to almost be a year that I've had a reliable DD that starts up every morning.
3) I have a front strut brace, just curious how much higher, if any, a carb would sit than the stock 1.8L manifold.

1) Depends how you tune the carb. K-jet is probably more set and forget in the long run, but I suppose it all depends on what you want out of this build. If you ask me, a pair of DCOE 40's would suit your needs pretty well. Tuned properly with a wideband 02 sensor, you could easily obtain MPG figures which are similar or the same as the K-jet. I can't promise better, but the performance difference will be night and day.

2) Depends if you want to buy them secondhand. If you can find a reputable carburettor shop that knows what they are doing with Weber Carburettors, buy a pair of rebuilt and reconditioned DCOE 40's instead of buying brand new ones. You're probably looking to spend around 1000 dollars extra in total with the conversion for twin Weber's if you wanted to do it all properly.

- The plus point is, you gain a much broader powerband, more accurate fuel metering per cylinder, more accurate air metering per cylinder, killer throttle response. Peak HP/TQ numbers will increase but the power under the peak will be greatly improved. You can also tune the intake length to improve intake filling.
- They are very easy to change jets on and so long as you understand how the jetting works, they are easier than you'd think. Don't let all the numbers freak you out.

However, all that said, K-jet with a 2.0L AFM provided its all in top shape would be easier overall and wouldn't be bad.

3) Generally they sit pretty low. DCOE's sit very low, 32/36's not that high with an 02 solex manifold, can't speak for 38/38's. Shouldn't foul your strut bar, depending on the brand and construction however.

[skitzone]

Why such low compression?

[amarino]

It's not that low plus it is more than stock, which was 8.8:1. I also don't have money to get custom forged pistons.

[skitzone]

It's not that low plus it is more than stock, which was 8.8:1. I also don't have money to get custom forged pistons.

Fair enough, euro k jet 1.8 had 10:1 STOCK. so couldn't understand why you went 9.5:1.

[amarino]

Fair enough, euro k jet 1.8 had 10:1 STOCK. so couldn't understand why you went 9.5:1.

Damn those Europeans had it nice.


So I've thought of the whole carb thing and I think I'm going to stick with K-Jet for now. I don't want to attempt it and then not be able to spend the money to do it right. But I may entertain the idea sometime as a future project.

Right now I'm still looking for a 2.0L crank and 80mm AFM. If you have any leads, let me know!

[epmedia]

9.4/1, 9.5/1 is very good for North America 2.0L M10 (typical gas station fuels).
I heard rumor that 9.3/1 is stock for Euro 2.0L M10

I have the 9.4/1 dome pistons in my '78 2.0L M10 and it scoots pretty good compared to the other "stock" '78 2.0L I had.
This of course is with the proper 2.0L head...

[FranzE21]

For what it's worth, i agree with your initial spec. I'd use that 284 regrind cam and HD rockers with recommended springs and rocker locks. I'd throw on an adjustable cam gear, get compression 10.1-10.5:1 run it with 2.0L AFM K-jet and Megajolt.

Run it on your highest grade pump premium. The idea being that it is more beneficial to run at ideal ignition advance throughout the revrange and retard the cam timing if detonation is a problem. The ignition system is accurate enough to run timing to the degree in different load conditions, instead of the stock centrifugal distributor setups which have a advance curve which is less than ideal for a performance build. Distributors also have mechanical play/slop in them and timing can deviate by anything up to 4 degrees. The benefits of a crank trigger wasted spark programmable ignition on a performance build are highly advantageous.

With the cam gear and Megajolt ignition on there, the potential of the compression increase will certainly be usable and not a liability.

Be careful with IE piston top geometry, I find their piston dome design to be less than ideal for uniform mixture burn and detonation resistance.

Would highly reccomend a wideband 02 sensor to get your AFR's set properly with the Kjet.

http://www.innovatemotorsports.com/x...9&cat=0&page=1 I'll be using this kit. Datalogging and 02 sensor, and I'll request a gauge also.

ALSO, I noted the cast pistons you want to use are not for a 1.8i head, but actually for the E21 2.0L head (head designations are 121, 121ti, E12, E21 2.0, 18i which is yours). The dome shape is imperative. I would spend the extra 200 bucks and get a set of forged pistons, which can be specified for the 18i head from Ireland. Either that or see if you can get CP forged pistons from TEP cheaper, but I doubt it.

[hdx]

amarino I was just talking to my friend and he has a complete 1974 2002 motor he will sell for 250.00 and it is in running order 2.0 with a e12 head and a weber 32 36 carb and manifold.

[amarino]

Would highly reccomend a wideband 02 sensor to get your AFR's set properly with the Kjet.

http://www.innovatemotorsports.com/x...9&cat=0&page=1 I'll be using this kit. Datalogging and 02 sensor, and I'll request a gauge also.

ALSO, I noted the cast pistons you want to use are not for a 1.8i head, but actually for the E21 2.0L head (head designations are 121, 121ti, E12, E21 2.0, 18i which is yours). The dome shape is imperative. I would spend the extra 200 bucks and get a set of forged pistons, which can be specified for the 18i head from Ireland. Either that or see if you can get CP forged pistons from TEP cheaper, but I doubt it.

I was looking at a wideband O2 sensor as well, that seems to be a nice one. Thanks for that. Also see my earlier post below about the pistons:

So they do make pistons for the 1.8i head and everything else is the same (CR, size, and price), they just don't have them on the website. He explained that when they cast the pistons, they leave a little extra on the top then machine them to the individual heads. I just need to call and order them.

amarino I was just talking to my friend and he has a complete 1974 2002 motor he will sell for 250.00 and it is in running order 2.0 with a e12 head and a weber 32 36 carb and manifold.

Damn you, 2 months ago I would have jumped on that right away but now I already have a complete engine, all I would really want would be the crank. I'm sure he doesn't want to part it out. If it does come to that, let me know. Thanks, but no thanks.

So I called 2002AD in Pomona, California asking how much a 2.0L M10 crank would cost, they quoted me $300 for one. I was at Ireland Engineering one afternoon picking something else up and Jeff over there had quoted me $130 on the low end which I can see myself paying. The local pick-a-part sells used cranks for $40 but you have to pull them yourself. The issue with the pick-a-part if finding a 2.0L M10 to take the crank out of. I may have another lead but if anyone else has a 2.0L M10 crank which they don't need and are willing to let it go, lets talk.

hdk: That complete engine is looking kind of good now that a crank alone will cost me $50 more

[FranzE21]

I would drop everything and buy that 2002 motor. Absolute bargain. E12 heads are also good.

[century e21]

amarino I was just talking to my friend and he has a complete 1974 2002 motor he will sell for 250.00 and it is in running order 2.0 with a e12 head and a weber 32 36 carb and manifold.

I would Lowe to buy 2L 2002 engine.
BC. Vancouver Canada

century e21