318i to 318is engine twin cam conversion. Plus m42 2.1 Build

[Gortour]

If the engine in the scrapper E30 iS is still there, will the scrapyard consider swapping lumps with you?

[Alburglar]

Tried that it's a no. He doesn't even want to sell it but I persuaded him.

[uzdubmwe30]

Its not that different dude, the c101 plug is just plug and play, dont give up that easy on the first engine.

[tim_s]

keep the e36 engine, jsut use all the ancilliary bits (loom etc) off the e30 dude!

[Alburglar]

Which is the c101. is that the big round jobby that lives at the bulkhead? I just need to get this straight before I spend any more cash.
-If I use the E30 loom do I use an E36 or E30 Ecu?
Also e36 lump is only 4bhp up on the E30 so I am still swaying towards buying all the bits from this e30.

[tim_s]

i'd use e30 ECU, E30 manifolds, E30 everything other than actual engine.
e36 engine is better, some of the teething issues with the e30 were nailed with the e36. the very late e36s are even better. seeing as you already have the e36 engine, wouldn't really make sense to use an e30 one unless it's a corker and the e36 one a nail.

[Alburglar]

I can't decide at the moment. I'm ringing him tomorrow for a price, i'll find out it's mileage and make a decision then. Trouble is I don't reckon He'll flog me the loom without the engine so I've got my feelers out for an e30 loom just incase I need it.

I have figured something out tho. All the M40 gearboxes had a 3.38 final drive and the M42's have all got 3.45 FD, so I may stick with my gearbox, if any prop issues arise, as I don't make much difference.

[uzdubmwe30]

c101 is the plug at the baulkhead yes

[Alburglar]

Right folks. Today I picked up an E30 318is engine, loom, ecu, manifold, inlet, afm and even the brackets that weld to the wing to fit the coil pack to. So the twin cam conversion is now back on the cards, but from a much better starting point!

[Alburglar]

Well after a couple of days hard graft, it's done - ish. Old m40 engine is out and New m42 engine is in:

No real drama's - just my own stupidity waisting a couple of hours trying to get the engine off the gearbox with one bolt left in - doh!
I have found out tho that you can either use the round type engine mounts (from the IS) or you can use the diamond shape block one's (from the 318i) by simply turning them upside down!
It is ready to go and I have had it running briefly but it sounds like a tank at the moment because the exhaust isn't back on...
... and this is the only real issue, my friend and another BMW specialist garage have looked in three exhaust books and I cannot find where you can buy a new front section for a pre 1990 (non cat) 318is. Anyone got any ideas?

...and yes the coil pack is tied on with string, I'm just waiting for my painted brackets to dry. lol

[jaistanley]

Second hand I'm afraid. Exhausts for iS's are hard to find. I actually have some 2n'd habd stuff here.....

[Alburglar]

Got a front section then mate? prepared to post it?

[Alburglar]

Found a front pipe at the breakers.
Thought I'd touch on some of the things I encountered doing the conversion incase it helps anyone considering it. Firstly, the IS has a bigger rad and you'll also need it's px side lower rad mount, it's longer top hose and preferably it' cowl. But I made a simple little bracket up to use the 318i cowl:

As mentioned before you do need the coil pack brackets from a donor car (see below), unless you want top make your own.

The accelerator cable also has a different end on it (which I lost- doh) so I cut my 318i item down to fit in the bracket and used a solderless nipple to keep it in place.

[Alburglar]

The 318is exhaust front section was too short and didn't meet the rear section on my touring, so I cut off the front silencer and extended the pipe. Perfext excuse for a home made straight through pipe.

[ShepsEvo3]

Nice easy worthwhile straight forward conversion

[Alburglar]

Now goes like shit off a shovel compared to 318i engine.
I now have a larger 325i throttle body headed my way, once that is on a chip is next on the list.
Then at some point a small case lsd.

Plus fixing up an IS front spoiler to tart up the front a bit.

[appletree]

How are you going to frit a 325 TB there totaly different shapes! you may also have trobly with the mapping as with the M42 Tb theres two butterflys which open at different times so the map will bematched to them opening rather than one big one opening.

That is unless you get it live remapped

[Alburglar]

I will fabricate all that is required and the ecu map has got feck all to do with wether the air is let in by two flaps or by one! You could run it with mild power gains without touching the ecu, but I will be chipping it for maximum effect.

ps, love the super charger conversions. I used to have an eaton M45 knocking about, wish I'd kept hold of it. Will be rolling roading once car is done to see how much power is possible from a parts bin tuned is lump!

[Alburglar]

Megasquirt built into stock ecu has arrived. - Thanks Hoshy
Individual throttle bodies on the way. - Thanks Chips
Standard lambda will be retro fitted to start with. just need to order collar to weld to exhaust.
Coil on Plug conversion from my friend is on the way too.

Once I've base mapped it. I will put it on the rollers for some figures

[Brian28]

Look forward to seeing the roller results for comparison, I'm doing something similar but UnichipQ piggyback ECU and R1 bike carbs.

[Alburglar]

-I opted for a bored out m42 throttle body in the end.
but anyway engine is dead, so I've removed it.

I've got another m42 to go in it, whilst I gather parts to rebuild as a 2.0 or 2.1 stroker, which I will post up as and when anything interesting happens.

[Alburglar]

Parts Acquired so far:
BMW E36 M3 3.2 Evo S50B32 conrod and piston set of 6. Pistons are 86.365mm!

Got them very cheap. 5 are in very good condition, 1 has ultra fine marks where 1 big end bearing started to ware, although this is very fine and would probably polish out. But Ofcourse I only need 4!

[Alburglar]

Just Purchased M47 88mm crank from Rover 75 Diesel!

[tim_s]

Just Purchased M47 88mm crank from Rover 75 Diesel!

Sorry to be bearer of bad news but Rover 75 88mm crank has a stubby nose not a long nose Well the ones I've seen do at least. Makes it more hassle than it's worth (might as well just go 90mm if you're going to do that much work to crank nose).

[Alburglar]

Oh dear. I thought that was the exact one I needed. I was feeling very pleased with myself until you said that.
I'll have to lay it next to the m42 one and see. Fingers crossed.
Which cars are more likely to have the long nose?

[tim_s]

easiest place to find one (88mm) is pre-facelift 320d m47...

[Alburglar]

Do you know what years they are tim?

[Alburglar]

Right, who's gonna give me the bad news then. Is this a stubby end? Looks short to me, compared with the pics on Metric Mechanics. Its M47R 88mm. Its 34mm or about 60mm measured from the start of the collar.

[tim_s]

yup that's the rover crank with the wrong nose sorry dude

[Alburglar]

Bugger. Can't find a 88mm 320d one anywhere!

[Alburglar]

They are like buses these M47 cranks I now have found two from pre facelift e46 320d's. Just confirming the details, but i will be buying one. And the bloke who sold me the stubby 88mm M47R is willing to swap it for a 90, so I'm gonna do that too. Then I can persevere with the 90mm and if that is too expensive/complicated I'll have the 88 as a backup!

[tim_s]

Good news! I'd personally not bother with the stubby nose 90mm and just use the 88mm - what rod length are you going to use? The m4x struggles for block height to pull off a decent rod ratio with them, for the tiny increase in capacity it's just not worth it to go 90mm for the potential increase in wear. Also there's a long nose 90mm you can get too...

[Alburglar]

I want to use my e36 m3 s50b32 conrods which are 135mm and pistons which are 86.4mm. The reason I wanted to persevere with the 90mm crank is that I'd read E36 S50 B30 US M3 pistons which have 86mm diameter and 32.8mm compression distance plus 135mm conrod length, the resulting displacement would be 2,091cc (86mm x 90mm) with 1,5 conrod ratio. Off course, I will have larger pistons, so the maths will be a little different. The total deck height will 211.80mm or it will sits 0.35mm lower than M42/M44 standard deck height.

Sound right or is that retarded?

[Alburglar]

Well interim standard(ish) m42 engine is in, just needs fluids before I start it. But everything has been a bloody struggle. A couple of rounded off allen bolts on the old clutch had to be cut off. The spigot bearing was too small and engine wouldn't go on m40 gearbox. For those that don't know it is located in the end of the crank here behind the clutch.
I got the pilot / spigot bearing part number off realoem but all the parts places computers said it was a clutch release bearing, but I ordered it anyway to see and it is the correct spigot bearing, so don't worry if you end up in the same situation.
Part number is: 11211720310
Sach's part number is: 1863869036


old one and new one

I can only assume it's the bearing to suit an M10 gearbox?
Anyway it's all back together and fingers crossed new engine isn't a piece of shite.
I also took the oppurtunity to take some pics of other bits and pieces i'd already sorted, when car was still on the road:
Exhaust manifold had cracked the whole way round, so I welded it.

I had also previously got rid of the horrible mess of engine breather and water hoses under the inlet manifold and leading to Throttle body heater plate. I ditched all the water pipes leading to TB and it only left two pipes spare, one in the engine block and one in the coolant bypass pipe on the side of the engine block, which I connected together with a new hose. (forgot to take pic, but found this on m42club)

I replaced the breathers with spare pipes connected together. It connects Idle control valve to the breather pipe on the front of the engine.

You end up with this shite,

apart from I have put my heater plate back on, simply to act as a spacer for the TB so my airbox sits on standard fittings

[Alburglar]

Stroker build update:
The bloke with the short nose 90mm crank sold it, even though i'd paid for it? So he's now refunded me.
No loss because the long nose 88mm crank should hopefully be here this week.