upgrade to a 318is

[Martin347]

Thanks Tim, my project is putting a 318is engine into my 325i (abit disheartening really!). The reason for this is that I have been doing the car up for rallying for some time now, but just as I was nearing the completion of it, the msa have decided to ban 6cylinders from jan 07. So now I have found myself a 318is (m42) engine and am hoping to get the power up so that when I swap the engines I'm not going to be disapointed with the power loss. At the moment I think I'm going to swap the crank for the m44 crank, i'd like to bore it out to 2.1 like you are doing but that depends on how much the pistons will cost me, up the compression ratio, a pair of hotter cams and the lighter flywheel. What do you think? Any suggestions would be greatly appreciated!

[tim_s]

hi all,
thats cool james. its good isnt it? let me know how you find it in terms of fuel economy and fuel mixture, be interested in your opinion. its weird how the m42 is overlooked quite a bit for performance, i guess it was marketed to compete with GTIs etc without stepping on the 325s heels, but there are plenty of things that can be done with it to up performance. there's plenty of people who will spend Ԛ£1k/1.5k on an m20 to get it's performance upped a bit but very few people who will give it a go with an m42, and imo the m42s got as much potential.

tommy, i'm very interested in whatever you end up doing. I've never found any disks that I'm 100% happy on using with the e30. I've considered G60 disks, which will give 280mm, but they are a few mm deeper so will change the offset plus the centre bore is too small so they'd need to go on a lathe before going on. mind you, they'd give a narrower track than swapping to m3 disks! i always meant to look into volvo disks as apparently some of them might go.

martin, on a budget i reckon putting in an m44 bottom end is the best idea. there's no limit on what you can do really, hartge did a 2.3 m42! its all about money though. my bottom end will cost Ԛ£1k and i got the bits together pretty cheaply.

i want to get my throttle bodies back and have another go at mating them up! getting a bit impatient now, though realistically it'll still be a few weeks at minimum before they're finished. i'm trying to figure out how i can get the whole s50 trumpets in, they're long but i want to keep their trumpet length if possible as i'm guessing bmw have them tuned towards giving good road performance. anyone have any input to give on trumpet and plenum design, i really don't know enough about this, hence why i'm trying to keep everything original bmw s50 (well 2/3 of a s50) spec. i'm a bit worried about my lack of knowledge in this area!

[Demlotcrew]

Did hartge do a 2.3l M42???

Andrew

[TommyC]

Tim, I dunno if you'd be able to get hold of him, or whether you'd have to send an email to the magazine, but Dave Walker who writes Practical Perfomance Cars might be able to shed some light. He seems to be their engine and fuel injection guru. He does a lot with emerald stuff and is, at present, doing a fuel injection guide in parts in the magazine. Might be worth a try???

[tim_s]

dave walker

and yeah andrew, hartge did a 2.3, 99mm stroke or something around there... think they do something a bit criminal though, can't remember what it is, might be a spacer in between block and head or something, or i might just be making that up.
can only find it for the m44 at the mo:

http://www.birds.uk.com/parts-database/ ... 366230.pdf

costs Ԛ£4.5k before fitting, Ԛ£1.5k fitting.... a bit more than i'm spending then.

[Demlotcrew]

Yeah see i think they only ever did it on the M44, i dont think the block could house a 99mm stroke crank. Unless they shaved metal off the insides.

Andrew

[tim_s]

i don't know for certain, but i am not convinced that its just m44. i thought i remembered seeing an e36 pdf a long while back for the m42.
think the only reason i couldn't find it in birds was cos they've stopped doing it now - they only list this conversion for the z3, under e36 etc there's nothing.

i'm not at all convinced that the m44 casting is much or any different to the m42 in this respect, i've checked a m43b19 against an m42 and its pretty much identical other than the bigger bore (and diff pistons and one way valves). also you could jsut use an m44 block with the m42 head, this definitely works. plus there's room in my block with my crank in it, can't imagine another 5mm throw will make much odds, the bottom end could easily be clearanced - if there were issues i'd imagine it would be 1 or 2mm max that would have to removed - so a real non-issue.

[tim_s]

still seems like too long stroke to me, not really what i'd go for.

[dark_sounds]

sorry to jump in.... just wondering,, the M44 bottom end can be combined with the M42 bottom end no problems?? so just plug and play as such?? so if i kept my top end,,, just change the bottom end,, then i get 1.9 318is basically???

[tim_s]

there's a few people out there with m44 bottom ends on their m42s (not on this forum), so it can be done, but having not done it myself i wouldn't want to get drawn into the specifics. i wanted dan to do this, but don't think he will. btw anyone want my existing m42 block when my conversion's finished if dan doesn't have it (dont think he will)? can sell it with 330i pistons which is half way towards a 2l conversion! could also build it up for someone as a 2l if required...

[Demlotcrew]

Just had a look at that PDF and yeah 2.3l M44!!! Thats really interesting, would be good to know how they did it.

Andrew

[tim_s]

is pretty cool isnt it! i still am not convinced that having an engine so off-square would be in-character with the engine though. my 2.1 will be squarer than both which i'm quite happy about.

i guess thinking about it logically, i'd put money on my assumption that they used a spacer between the block and head being correct, either that or that they lowered the position of the crank in the block. maybe the latter is more likely actually, this would be the best solution. this must be the case due to rod-ratio concerns with such a massive increase in stroke.... or they did neither and just built an engine that wouldn't last!!!!

[TommyC]

That all sounds dodgy to me!!!! Head spacers or crank spacers !!!!!!

I'm very tempted by that 2litre tim but I think i wanna get mine on the road first and see how it is on it's first rally marshalling experience!!

Looks like i might be struggling to find the money to insure it

How much would you be looking for it, as a matter of interest??

[tim_s]

hi tommy,
yeah it sounds pretty bad doesn't it! but hartge have a v good reputation so its probably executed to a high standard, whatever they did. if i had the good fortune to find one, this probably wouldnt put me off buying it. would love to know what they actually did though, its really intriguing. i may be completely wrong and they could've done something else weird and wonderful.

i'm after Ԛ£200 for the complete bottom end, i was going to do a deal with dan where i threw in the 330i pistons (shorter height so useful for stroker conversion) with it for that price. its minty mint, 112k, history, and in the car so you can check it out properly. i did a bit of an advert ages ago for it in the for sale section.
however, if you're struggling for money its probably a very bad idea!!! will cost quite a lot when all said and done! you'll need to source a stroker crank and a headgasket which will cost another few hundred.
still compared to the Ԛ£3k or so tdi want for a 2l conversion i think thats pretty good!
i spose a cheaper project would be just to overbore with bigger pistons and balance....
all depends what you want. Ԛ£ per power/torque i reckon modifying the bottom end is a good idea, think you can spend a lot of money on other stuff that wont give the same gains, but i guess it is a big outlay in one go.

btw i also have m42 crank, rods and pistons i want rid of (from the engine i'm rebuilding!), m20 rods and soon a load of other bits that will be put up once my project draws to a bit of a close.

[TommyC]

Cheers for that mate, but yeah, i think i'll bide my time and save up. I might just get the rattly top end sorted, keep an eye out for some S50 throttle bodies and make my mind up when i'm nearer to doing something.

I might see what sort of gains you'd get on throttle bodies with a Mega Squirt setup......

Probably not a good Ԛ£per BHP gain but i like the noise!!!! And the challenge of putting it all together. Don't really have the patience for a full rebuild (nice idea but i know what i'm like.... i'd never get round to finishing it...... ).

[cheesebox]

I was just having a slghtly e30 biased but fairly random browse on the web, and came across this...

AC Schnitzer are still making a performance upgrade for the e30 3is, the AC Schnitzer 318iS Camshaft Kit, no less!

Look under products, choose E30 (E30 up to model year 1990)

Anyone heard anything about this, reports from the field etc?

I can't find much reference to it. Brian Purcell seems dubious about camshaft upgrades, but I'd have thought there'd be some decent power gains to be had with a carefully remapped chip.

Dread to think of the price of this baby though... Group buy anyone? (lol)

[tim_s]

hartge do a kit too. Ԛ£1200 parts, still available. not sure what exactly it does.
its brendan purcell btw.

[tim_s]

what do people think of this:
http://www.e30zone.co.uk/modules.php?na ... ic&t=27553

[cheesebox]

hartge do a kit too. Ԛ£1200 parts, still available. not sure what exactly it does.
its brendan purcell btw.

Brendan, my humble apologies! I'll go out and come back in again.