upgrade to a 318is

[tim_s]

oh yeah the spec i'm going for is 2.1, 11:1 CR. i want to go for a higher Cr, but its my daily driver so i'm trying to keep myself in check!

[astondg]

I'm a bit late here but I don't think all multiple throttle bodies will loose torque down low, it depends a bit on how they are made. If they have longer intake runner bits (or trumpets or whatever they call them) they can make more torque than short ones. I think the ones on the M5 are reasonably long and probably don't cause much of a loss to torque. You also get the benefit of better throttle response. Like you said though, not necessary to start with and not a lot of gain on a lightly tuned engine.

Aston

[tim_s]

sure, but i know sepcifically that the dbilas ones do sacrifice some torque at low revs on a standard engine.
i've always wondered whether the size of the plenum chamber (the dbilas ones have a plenum chamber not just socks) has an effect too? if its larger will it smooth out power delivery etc?

[redrobbie]

I'll be waiting in anticipation, be sure to post the results.

It's about time this forum had a charged up (N/A tuned) m42.

[Dan318-is]

tim im currently running KnN filter panel and big bore throttle body thats it!

i did have a viper chip but it did nothing for my ECU
iv got this other non standard chip too but have not got around to posting pics up, iddentifyying, and if necessary installing it,

id like to put a supersprint exhaust on next, this is more of a need as my current one is blowing an MOT due in march.

after this id like to adcance the inlet cam timing 5degress but i jsut havent got the knowledge

then like you say, im guna get it on the rollers.

before all htat though im changing my brakes!

[astondg]

i've always wondered whether the size of the plenum chamber (the dbilas ones have a plenum chamber not just socks) has an effect too? if its larger will it smooth out power delivery etc?

I don't know but I have a book here about engine tuning that has a section on throttle bodies and stuff. I'll have a look and see what it says.

I think BMW likes to tune for torque so maybe the M3 throttle bodies, plenum, etc. might not loose much torque (if you use a scaled down 4 cylinder version of the whole thing I mean)?

Aston

[tim_s]

redrobbie, will keep you posted. but bear in mind mine won't be the ultimate m42 by a long way, this is just the start. i want to keep it as a daily driver, and this is just the first stage of my conversion - getting a new, sorted block in.
for the moment its going to have a fairly sensible CR, and no headwork, performance cams or standalone management etc that it will probably need to get the most out of it. i'm hoping to get a load more torque at sensible rpms, plus it to happily rev to just under 7k. it will be on standard injection with a custom ecu, which i'm not sure is up to it, but we'll see.
latest news is i'm trying to figure out if i can convert the chain deflection wheel to the slide used on the late m42 and m44 to save me Ԛ£75 on a new wheel... reckon the slide will wear the chain less too. got the block's water channels in a phosphoric acid bath as well to clean them up.

dan, get everything else done first, upgrade the engine last. dunno what happened with that chip, you checked your ecu number etc and made sure its ok? Might be worth getting fault codes read and everything checked out to make sure the car was ok. if you're ever anywhere near me give us a shout and i'll do the cam timing for you and we can try a different ecu in there too.

aston, you're probably right about the s50 throttle bodies. i'd be interested to hear what the engine book has to say on plenum design. not knowing enough about how to get the best out of throttle bodies is one of the reasons i'm leaving that well alone for the moment! i'll try to find out the results from the chap on the e36coupe forum who did this, as that would be interesting.

[Dan318-is]

i havent tried a viper chip on my new IS yet, that chip was on theh old one which is sitting in front of me right now,

the chip has 1996 marked on it lol! so dunno wot one it is

[tim_s]

not sure i understand you right, the ecu box has 1996 on it?! if thats the case no wonder it didn't work fella!
the ecu i have here (my original ecu from my car - i put the viper in a spare ecu as i didnt want to mess with the original and so i can do a r/r comparison etc if i can be arsed) has bosch no. 0 261 200 175 on it. it also has the last 7 digits of the car's chassis no. on the bottom. the one in the car atm has the same bosch number. check the one in your current car, if its the same hopefully you'll be ok.

[Dan318-is]

no the chip in the old one has 1996 on it!

the number on the box is the same as theone you quoted so deffo the rite ecu

[TommyC]

I have an iS as a second car. I'm gonna be using it to get myself to a few rallies in the new year (including Wales Rally GB). It's a bit of a shitter bodywork wise but that doesn't bother me.

I got this DVD for christmas



The M3 was the most spectacular Group A car of the early years and it even won the Tour de Corse 1987.


I want my car to sound like the group A M3's (and have a bit more poke at the same time).

Basically i wanna fit throttle bodies and was wondering what people think of my ideas so far (you in particular tim, because you obviously know your stuff when it comes to these engines!!)

I have been thinking of using Bike throttle bodies (prob 36-40mm ones) and modding a standard iS inlet manifold to fit them to. I was thinking of blanking off the injector holes in them, fitting the iS throttle sensor to them fabricating a plenum etc so i can use the standard engine management. What d'ya think???

If thats not at all possible i was thinking about using a megasquirt/spark ecu. I've been on the website and forums but it seems there's only two types of post

1) Hi, i've got a *insert car type here* and i've used magasquirt to fuel inject /turbocharge my engine. I had no problems installing it and everything went really smoothly. My car's now great!!

2) really boring/confusing sh1t that bangs on about injector impedence and stuff only electronics engineers understand

There's no middle ground!!!!

Anyone fitted Megasquirt to a BMW four pot?? Realistically how easy is it to install and set up?? (I suppose i'll need a four spark unit cos th iS has four coils in it's coilpack......)

[tim_s]

tommy, i'm not really the man to talk to about throttle bodies on m42s as i've never done it! there's better info on the web than i can give. there's a guy out there who has done this with bike throttle bodies , i just can't find the links atm. i can't see any reason why it wouldnt work. main concern has to be that it would be a load of work and may not give the gains you expect if you keep factory fuelling, head etc.
reckon if you're gonna get much from them you'd better to some headwork - put in solid lifters, wilder cams, flowed head etc. and go for standalone management or at least a MAF + unichip conversion to make sure the injection can cope.
might even be worth just buying the dbilas setup as although its pricey, its bolt-on. also if you're going for custom management the gttechnic throttle bodies are $1000 ish which seems pretty decent.
obviosuly then you wouldn't have to worry about how you'll optimise the trumpet length, plenum and bore etc.

this link
http://forums.bimmerforums.com/forum/sh ... p?t=459014
talks about diameters of throttle bodies etc.

as for megasquirt, thats been done too. i think personally i'd use emerald myself, its quite cheap now and you'll get great UK support to get you going. anyway, this user:
bmwman91
on bimmerforums has put megasquirt on (or is in the process of doing so) his e30 318is:
here's some posts relating to that:
http://forums.bimmerforums.com/forum/sh ... megasquirt
http://forums.bimmerforums.com/forum/sh ... megasquirt

[TommyC]

Cheers mate. I forgot to mention i'm trying to keep the cost down!! Thats why I was thinking of Megasquirt. Seen a few on ebay, ready built, that haven't been too expensive.

Plus I like making things. I did mechanincal engineering and fabrication & welding at college before I changed tack slightly and started fixing aircraft and jet engines for a living. I just love the challenge of solving engineering problems.

I'm not planning on marshalling any rallies between feb and july, so i might save up and go the whole hog (emerald etc). I do still fancy the challenge of fitting some bike throttle bodies though.......

[tim_s]

man, i used to marshall and do support crew stuff a few years ago. was good fun, but havent done it for a while now.
i think the bike throttle bodies would be superb for a rally 318is. anyone who makes their own stuff has my thumbs up!
if i had the tooling, didn't need the car to play nice on the road and could afford to take the car off the road for a while etc i'd be very tempted with something similar. i definitely wouldn't rule out using the s50 (e36 m3) throttle bodies either if you did build up a sandwich plate, i'm sure there'd be a queue of people wanting one off you (myself included!)!

[TommyC]

HaHaaaa!! M3 stuff sounds a much better idea!!

Had a look at Emeralds web site earlier. Their ecu's only support 3coils. Might have to get a vauxhall coil pack and bin the iS one. The vaux one is a wasted spark design so theres only 2coils that fire on 2cylinders at a time. Apparently better emissions cos it fires on the exhaust stroke to burn anything combustable thats left (I have a calibra 16v Redtop as my daily driver).

I just don't really fancy all the mucking about with wiring, but needs as must.

The more i think about it the more that car needs. It could do with a better exhaust cos the standard one has been buggered about with. At the moment it has some shitty old bike cans on it that i reckon are cousing a serious restriction. The engine isn't happy at idle, a bit lumpy at the moment.

I also want to fit some bucket seats, which means i'll have a leather recaro interior for sale in the not too distant future!!

I'm doing the suspension (back to Standard m-tech springs, need the ride height) and removing the window tints soon too.

One of the rear arches has been buggered up too so i'm on the lookout for some sort of arch extensions to cover it up for the MOT.

It'll be all go soon!!

[tim_s]

here's the dbilas ones:


and here's the s50 ones:



i must admit now that you've got me looking at it i'm a little tempted to play with some throttle bodies... but i reckon i'm better off concentrating on getting the rest of my engine conversion sorted first though, i'm throwing enough money at it as it is. I like the look of that dbilas kit, it really is a nice design. i haven't made up my mind on whether doing the s50 throttle bodies straight to the head as with the second picture is better than using the original lower intake manifold and its injectors with some other throttle bodies, to give something more like the dbilas kit.

bit of a pain to have to change the coil with the emerald, not a biggy i guess though. i just took a quick look at their site though, it is a fair bit more expensive than megasquirt isnt it!

[TommyC]

Damn that all looks so Cool!!!!!!

Not sure i like the look of that plenum chamber on the dbilas ones though. Looks like it'll starve the front cylinder of air??!!!

Having never seen the M42 inlet manifold/head apart I couldn't say for sure but if you take a bit of time with the sandwich plate for the S50's I'm sure you could get the correct port shape for the injector to fit etc. Especially if you'd had the head gasflowed.... Or by making it 15-20mm thick, that'd give you enough meat to play with.... Looks like it may have to be wedge shaped from that pic though....

( too much to think about, and now I want some cos they look all cool and shiney and stuff muuuuum, it's not fair )

Getting to Emerald, I like the idea of proven professionally built kit with decent technical support on the end of the phone etc. But Ԛ£550+vat just for the ECU seems a bit steep!!!

However, the idea of mucking about with megasquirt makes me nervous. Although I sometimes think "you're a professional engineer for god's sake, it's only some wiggly volts and electric string conected to a little box. Stop worrying, get in there and start doing......." (then that little voice pipes up and says yes, but it has the potential to so horribly wrong!!!)

Oh well, i'll get round to it at some point...............

[TommyC]

Where do you find all these pictures from?? I've tried a few searches in a few places but never seem to come up with anything good.....

[tim_s]

tell me about it, also just contemplating the idea makes it a challenge i want to overcome. was the same with the 2.1l thing i'm doing at the mo, kinda want to do it just to prove i can!

the top pic was on BP's 318is site, the second was from a chap on e36coupe forums who did the very thing we're discussing, but never got around to finishing it. i've asked him to take some photos of the m42 inlet vs his sandwich plate for me to see how well he's addressed the injector thing. I took a look at the etk earlier, here's what i'm concerned about injector-wise:

M42


S50

[tim_s]

i don't really know how i've come by that stuff, my last job was pretty dull so browsed forums a bit at work i guess! i spose i've been kinda involved with bmws for years as well, even if driving other cars. the zone wasn't about back then so you had to be a bit imaginitive to find info so have an occasional look on quite a few bmw forums.

[TommyC]

The site wouldn't allow direct linking, but i've looked at them in separate windows.

I see what you mean. I don't think this will be a real problem. It looks like the S50 injectors are at the same angle but are just a bit further over (looking along the engine with the cylinders in line). You could make the plate taller to seal properly on the M42 gasket and just leave it like that,

OR make a manifold out of an M42 one, use the original injector holes and blank off the ones in the S50 TBs

OR take the head off, get the notches welded up, have the head gas flowed afterwards keeping port size and position in mind with a view to mounting the TBs direct to the head (if not possible stick to the plate idea).

I'm liking this S50 idea the more i think about it, where can i get some from???

[Andy335Touring]

I have to say from my experiance with messing about with trying to make an adapter plate for fitting some M5 TB's to my M30 that you are better off cutting the mounting flanges from the TB's and the inlet manifold and then welding them back together so they bolt straight on to the head with less chance of air leaks.

Depending how you did it you should(touch wood) be able to duplicate the stock injector angle as well.

Like said before on this thread the port shapes probobly won't be the same so you might have to sort this out by grinding and/or welding to build the right shape.

I started making this adapter plate as i was wrongly(sp?) informed that you couldn't weld cast aly, i might eventually bin the adapter plate and weld the flanges ?



And this is an M30/M5 TB set up thats been welded.

[TommyC]

Lookin good Andy!!!

Someone thats a bit handy with a decent TIG welder should be able to make you up a nice manifold out of the two. If only you were nearer Hastings i'd recommend a place to you (Gareth had the ports on an MI16 head welded by them to fit carbs when he had his 205gti. Same kind of problem as the M42 cos the head had clearance notches for the injectors).

I'm now itching to get at my car and start measuring and visualising things but it's 150miles away at work (RAF Brize Norton) Damn!!

[Andy335Touring]

Cheers for the offer but i've got a bloke local to me for the TIG welding.

I had to get a dip in the TB ports filled with weld to get the ports to match up. This was just after i got them back and just started to grind the weld on the mating face.

[TommyC]

Just been looking a bit closer at those etk diagrams and I reckon theres a chance you could mount them direct to the head. Looking at the stud positions and port shape there doesn't seem to be much in it at all!!!(except for the notches in the M42 head) The simplest way to check it all would be to get some gaskets for both and line them up......

Ooops, sorry andy, i'm back to thinking about S50 stuff.

Looks like you might wanna smooth things off a bit inside them too!!!!

[tim_s]

details for evo engine:



it is only the injector 'notch' that is really signifcantly different, the port sizes seem similar.
i think the requirement for a angled spacer plate may be that the injectors otherwise will fire into the edge of the port rather than into the middle and onto the back of the valve.
i've also looked up s50b30 and b32 (evo) throttle bodies and the part numbers are different, so more info is required there on what the differences are.
as for buying the throttle bodies, try www.partsgateway.co.uk, findapart and keep an eye out on here, e36 forums and ebay. there's thousands of e36 m3s about. i'd have thought Ԛ£200 with the fuel rail and trumpets would be about the mark. would wait until you know diameters and stuff first.

[TommyC]

I think we could be on to a winner for direct mounting then!!! The other thing that needs checking would be the pitch between the ports on both. And obviously the mounting studs/holes (although they look to be in the same positions on etk they might be different distances apart etc).

I'm not too worried about the diameters if they're iro 40-50mm. I read an article on fuel injetion in PPC a few weeks ago (think it's Dec issue) and it said if you have slightly oversize TBs it's not a big deal. Once you've set up your ECU there shouldn't be the same problems you have with carbs that are too big - airspeed too slow to draw the fuel out of the jets - because you have injectors, the only drawback is your effective full throttle is before the butterfly is fully open. So this just means the last bit of movement is redundant.

I'm confident you could get 50mm TBs working on an M42 but you'd just have full throttle just before the pedal hits the stop (which might not be a bad thing???).

[tim_s]

i'm pretty certain the pitch is the same, think that's why people use these in the first place. never done it myself though, so can't say for definite.
the bolt pattern must be different as there's three on the top of the m42 inlet manifold, 4 on the s50 (2 on each tb)
as for tb size, i know the e30 m3 tbs are 46mm, and 48mm on some of the later ones. i'd be surprised if the s50 ones are any bigger than that.

[TommyC]

I think you could get away with clamping both TBs with one stud. You
could file down the edges of both untill they fitted next to eachother
around it so they'd have half a hole each (just like the bottom hole on
the inlet gaskets/seals are shown on etk).

Then use a large diameter washer to clamp them both down (maybe even
modify it so the clamping force is further away from the edge so the washer's not trying to wedge it's self in between them,
if you understand what i mean??)

If they're not close enough to touch then you could just make a clamp
that goes on the stud and holds both down.

It all depends how close they would be to each other.

46 or 48 mm would be ideal imo. I was talking to a mate earlier about the injector issue.
He reminded me that the further away from the ports they
are the more top end power you can achieve, but this sacrifices throttle
response. I dont think their position in the S50 TBs will cause any
headaches (it just depends if they point straight at the side of the port??).

He then started on about fitting eight injectors, four further up the ports,
and setting up the ecu to switch to them after a given rpm (4000 for
arguements sake) so you can achieve greater power......

I think i'll leave that for much later on (maybe not bother at all).....

More food for thought though!!!!

[tim_s]

i think your idea for clamping the tbs with one stud instead of the two is a good one. on the pics from the chap with the red throttle bodies, the throttle bodies are just about touching, and that's with the sandwich plate bolted on so would be as it sits on the m42. so it would make perfect sense to do it this way.
will be interesting to see how all this mates up. i've added some photos to this post which should help clear things up from etk diagrams.
all this discussion and the challenge of doing it makes me want to get some and have a go.
and interestingly that s42 in the pic i put up earlier in the thread uses 4 extra injectors further up the ports, just as your friend suggests.

i'm not really in a position to comment on the appropriate throttle body size for our application, its not something i'm clued up about, just figured that original e30 m3 size of 46mm would probably be about right.

i've got some pics here that i thought might help contribute a little. looking at the 'notch' for the injector on my inlet manifold gasket, its clear its quite a bit bigger than the notch on the cylinder head, which is good news

[tim_s]

is an e36 m42 by the way hence the newer pulley design. no apologies for the wrongness as its a nice engine!

[TommyC]

I wouldn't have known the difference between the two engines anyway. I'm fairly new to all this BMW stuff. My knowlege lays in the relms of vauxhall (dare i say it!!!!). However I am learning quickly!!

I've been wanting to put throttle bodies on my Calibra for a few years now but haven't had the time or money to do so. I've looked at all sorts of stuff (including the -expensive for what it is- DBilas option) whilst thinking about it all. But never got round to it cos I couldn't have my daily driver off the road for the time it takes to get it all done. Plus things never go smoothly with me and cars so I never took the chance!!

Looking at those photos I think you could get away without having to weld the head!!!!! You could smooth and profile the sandwitch plate to encompass (my thats a big word for someone as tink as i drunk i am, having just got back from th pub!!!) the radius so that little or on turbulnce is created by air rushing past it.

So all I'm thinking now is that you'd have to make a nice plate up to deal with the discrepancies (i'm doing well tonight) between the TBs and the head and you've got it made!!! Then all you've got to worry about is the ECU (Noooooooo not the wiggly volts and elcetric string!!!!!!)

(even though it's taken me the best part of half an hour to write this post, whilst typing very carefully, then go back and spell check it, I bet it's still illegible in the morning!!! I'll look forwar to finding out!!)

[TommyC]

Looking at the two photos on this page, I think you could blend out the notch in a kind of gas flowing way, do the same with the sandwitch plate and S50 gasket plate so things would be smoothed out even more.....

[tim_s]

i must admit i'm a bit of a fan of the red top engines, never owned a vauxhall though, been vws and bmws for me mainly.

doesn't look like the notch will pose any real problems, smoothing everything out a little seems like the most sensible way.
If i can get hold of some throttle bodies soon and most importantly cheap i may give this a crack.

i'm just trying to work out whether i'm gonna go for this at the mo, have still got a bit of a way to go with my 2.1 conversion, the pistons haven't turned up yet, need to get them cc'd and make sure my CR's gonna be where i want it to be, then need to get the crank machined and balanced, block checked and bored, the rods balanced and offset small end bushes mb, then new shells, bolts, gaskets (poss custom head gasket), timing chain, oil pump and assemble then put in the car. then i need to work out how much i'm going to do to the head while its off, at the moment, fingers crossed there'll be no nasties and i can just get it tested, change tappets (or go for solid lifters!) + inlet cam + carrier (noisy at the mo) and mb ask a mate to do any obvious porting. that's the stage at which the work for the throttle bodies can be done if i can just design a money tree or rob a bank by then.

[tim_s]

would love to see how fast it would be then though: 2.1, high CR, flowed head, solid lifters and throttle bodies....