Rotrex M42 Build - 285bhp little update

[appletree]

Dragged the car out and fitted the supercharger agin with the new bracket.

first time ive had the car out in the light for a bit and it still looks as good as ever.



i did however find some damage to the IS lip spoiler, looks like ive probly cought it with my great kanoo feet when ive been working around it and some paint has flaked off, i'll see if Beardy Matt can work his magic on it



Only small ish but still...


pics of the bracket fitted, much neater than the old bracket and it means i will be able to refit my old M43 power steering pullys so i can run flat belts.

[rix313]

Looks nice and shiney Going to give mine a bit of a good going over with some T-cut see if I can get some colour from it.

When do you want some monies for mine dude? Look forward to getting it but shan't be bolting it on just yet, next step is spending bout £500 on front steering and suspension

[appletree]

Small update, swopped my old v belt for the flat belt set up like the M43 has, but ive used an e36 323 pas pully and used a 4v belt on it instead of a 6v like the e36 uses as the pas drive pully on the crank has 4v's.

E30 set up


the two pullys side buy side


Flat belts fitted



Belt numbers for anyone who's intrested

[appletree]

Wahhhoo after what has basicaly been a year for one reason or another my bottom end has come

Spec is
M42 block with a slight over bore to freshen up the bores
Forged JE pistons 8.5:1 compression ratio
-ceramic coated crowns
-contact reduction grooves
-moly coated skirts
-pro seal rings
"o-ringed" block
Forged H-beam conrods
360degree thrust bearing upgrade
upgraded mains
upgraded big end shells
heavy duty wrist pins
M20 flywheel conversion
M20 325 clutch assembly
All balanced

The face and top of the block are shinyer than they look its just the camera hasnt picked it out to well

[m_jermyn]

Lookin fantastic mate... Very inspiring indeed.

Mike

[rix313]

Mmmmm

Must get mine sorted at some point

[appletree]

Blocks now on the stand in the garage ready for me to start building it up.

Ive lost the oil pump i bought about a year ago for the build so i'm now having to wait till wednesday for one to come in to nottingham stealers so i can then fit the timing case, bit of a pain as i had hoped to get a good bit done over the bank holiday weekend, ohh well, best laid plans and all that.....



Lots of new nuts, bolts, washers, keys, valves and timing parts



All the cleaned and resparyed engine parts, took adges cleaning all the crap out of all thw webbings and corners but the finish is much better for doing it



Front timing case Built up, near enough, need to take some of it apart again to actualy fit it once the oil pump comes.

[m_jermyn]

Wow this looks great and has got me excited as I get my m20b27 block tomorrow back from the sleaving and honing...... Very inspiring this is... Looking great

Mike

[GeoffBob]

The face and top of the block are shinyer than they look its just the camera hasnt picked it out to well

Looks well shiny to me Matt Well done on getting it all together. Always takes time, but will be worth it in the end

So now, with your lower CR, you'll be able to remove your "rev limiter" and start getting some serious puff out of your Rotrex at higher RPM. I bet you can't wait

Don't forget to keep an eye on those temperatures after the intercooler (as you did before) once you commence testing, and also keep an eye on your boost pressure (rising with RPM) to see if it flattens out at any point due to your intercooler or intake plumbing choking your air-flow. Although, TBH, I doubt you will see this happen since a) you will at best induct a maximum of 0.22kg/s of air into your M42B18 at around 1.5 bar boost, and b) your intercooler has a large cross-sectional flow-area.

What engine management are you using Matt, and does it have a knock sensor? A knock sensor would be useful to you when she does start making more serious boost at higher RPM - would be worth protecting those new pistons and your head.

Regards
Geoff

[appletree]

I'm using emerald m3dk management which I think does have the ability to use a knock sensor but I'm not currently using one though the e36 M44 engine that's basically the same as the M42 does have knock sensor so there maybe away to utilise the M44 one on my build.

As for the build I realy can't wait to get it built up and run in, need to decide what oil to run it on to, there must be better oils at a price that are more suited to this kind of application, but I don't really no were to go to look for it.

There was a guy using a rotrex on Peugeot gti-6 who was using something called purple racing oil that had something like a 100 times stronger shear strength than regular oil, he used it after running 440hp on the 2ltr lump and taking out the standard mains shells.

Anyone got any thoughts on the subject

[GeoffBob]

I'm using emerald m3dk management which I think does have the ability to use a knock sensor but I'm not currently using one though the e36 M44 engine that's basically the same as the M42 does have knock sensor so there maybe away to utilise the M44 one on my build.

Definitely worth looking into. Not to say that you would have problems with detonation, but if it did happen for any reason you would like to know about it before its too late.

There was a guy using a rotrex on Peugeot gti-6 who was using something called purple racing oil that had something like a 100 times stronger shear strength than regular oil, he used it after running 440hp on the 2ltr lump and taking out the standard mains shells.

Think you may be referring to "Royal Purple".

[appletree]

That's the stuff, just looked it up, looks good stuff have you had experience with it before or know anyone who has? Or have you got any other recommendations.

[smith4130]

any chance of a copy of this drawing or a better pic...?

cheers.

[appletree]

Good bit of progress in the last few days.

New oil pump fitted, all oiled up.



New timing chaionj sprockets allround. noticed the key in the crank had started to shear so ive replaced it with a new one.



unfortunaly one of the cam carriers has been damaged while the carriers have been in storage so ive had to clean it up, used some very fine wet and dry and some engineers blue to make sure i'd cleaned up the bearing surface.



My large collection of M42 hydrolic tappets. used the cleanest looking set which was from a low milage rebuilt engine which i think Tim_s sold me ages ago.



The cams all laid out ready to go in to the head and be built up.




ARP head studs in, cleaned the block threads before the bottom end was built so the studs went streight in.



head on. used my ARP head studs, bit of a issue, every one whos used them on M42s has told be that they went to roughly 65-70ftlb but the ARP instructions said 32ftb then 90 degrees then an additional 90degrees at 32ftlb + 120degrees we were uo to 70-75ftlb so i stopped thinking the extra 60degrees would take the torque on the to side of 85ftlb which i though was alot so want to check with a few people first.

the BMW manual say 20ftlb then 90 and 90 which i guess would be about were i am now.

also i've had the block wire ring/O-ringed which will no doubt be stopping the fire ring squashing as much as it would do normaly.




Finaly got the rest of the timing gear in with my dads help.

[appletree]

any chance of a copy of this drawing or a better pic...?

cheers.

if you click on it you can make it bigger save it and you can zoom in on it and see the dimensions. the only other view i have of it is as an autocad file but i think you have to have autocad to view it or if there is another way i dont know how to change it to a JPG file for instance sorry

[smith4130]

lookin good matt...!

no worries about the drawing, managed to mock one up yesterday in stainless...

but, what valve spring tool did you use...? i need to buy one soon.

cheers

[GeoffBob]

Matt, your engine looks fantastic! So clean I feel the urge to eat off it

FYI: Don't confuse BMW with ARP specified torque settings

What is important, ultimately, is the pressure (force per unit area) exerted upon the gasket by the head and block as the two squeeze the gasket between them.

Now (this is the important bit) two head bolts/studs of differing composition steels with different hardening processes, will need to be torqued to entirely DIFFERENT values in order to achieve the same clamping force on the gasket.

A further factor that you must take into account is that around 80% of the torque you apply to a bolt/nut goes into overcoming the friction on the thread while turning the wrench. Hence, for any specified torque value to be valid, you must follow the manufacturers instructions with regard to cleaning and lubricating the thread before torquing. ARP, for example, supply their head studs with a moly based grease that you must use before torqueing.

The moral of the story here is that BMW specified toque values simply don’t apply since you are not using BMW specified head-bolts or a BMW specified gasket. My personal preference is to follow the ARP instructions to the letter.

[tez180]

Any decent hydrolic tappets left

[appletree]

i understand that the BMW and ARP instructions are unique to the bolt/stud they come with but this build is all abit odd ball. the studs for instance are realy for M50 2.5 24v motors but they are the correct length to suit my application so ive used them. i can see in pricipal there isn't much difference, there still in a cast iron block going through a head of the same depth and material.

i was just going on what others have done in the same situation which was use the instructions as per ARP but they said they were getting to 65-70ft/lb.

I can still get to the head studs to add the aditional 60degree need to take them up to match the ARP instructions. this is what you think i should do? up to this point i have followd the ARP instructions to the letter, regarding cleanliness and using the moly grease just not the final 60degrees, having said this leaving the head a day to "rest" wont have harmed anything.

Tim_s and Rob have added there info on the suject earlier in this thread

here > http://www.e30zone.net/modules.php?name ... tart=250ad

Geoff do you have the link to the thread you started for my rotrex charts? i cant find it and would like to go back over it.

[GeoffBob]

Geoff do you have the link to the thread you started for my rotrex charts? i cant find it and would like to go back over it.

It's here Matt.

[appletree]

Thanks for that Geoff god knows how i couldn't find it with such an obvious title. lol

[rix313]

If I ever get there mine won't look half as tastey as that. Nice work bud, did you still need a flywheel? I completely forgot

[appletree]

No mate, i borrowed one from a local bmw specialist.

when you took your engine out did you leave the exhaust manifold on or remove it before the lift?

Any tips for lifting it out? were did you sling it?

[rix313]

Left the manifold on the engine and seperated it from the front section of the exhaust. I lifted my engine out with the gearbox attached, will you be or you planning on leaving it in?

I used a rachet strap and looped it through the lift eye at the front, the eye at the back and then looped it around the exhaust manifold for good measure:





If that helps.

[appletree]

Good pics thanks. i was going to split it to save messing about with the clutch cylinder and make it a shorter package as i will probably be doing the lift on my own.

Do you have any of the front lifting eye brackets going spare as ive missplaced mine but it looks like a usefull place to sling it.

[Gunni]

The torque applied is also very much related to the thread itself.

The pitch of the thread will dictate how much each degree of nut rotation get´s transferred to pushing down on the head. Less push per rotation = less torque torque required.

M20 Raceware = 45nm max torque , and they are very very very fine threaded
M20 ARP = 65lbs is about the max you´ll see.

As I PM´d you , follow the instructions.
Ideally you set them all to 32lbs and then WAIT for them to get loose a bit, which they will, then adjust back to 32lbs and wait again, when they are all at 32lbs and don´t get looser, then it´s time to apply 90 and 90 to them. This is the same for the ARP and ARP2000 studs at least on BMW applications. The 2000 will handle higher cylinder pressures before deformation occurs. Both will however handle ALOT.

[appletree]

Thanks for the PM gunni, i will be adding the last 60degrees later tonight.

[tim_s]

Nice work dude, just had a looky at this after the pm you sent! All very shiny! Mine used to look like that 50k miles or so ago when I first went 2.1. I've given up on a shiny engine in it these days, she's there to be used! I thought the 32ft+90+90 was too much, as they don't stretch that's a hell of a lot of torque you'd be putting the head through, I'd be scared sh*tless of damaging the head. As non-stretch bolts I'd be surprised if they're supposed to be torque + angle like the BM ones. Mine's sealed up, giving good compression, torque has been rechecked (no change, all remained at specified torque), head's been off after they're fitted and nothing nasty going on to it either, so by all accounts appears to be fine. Post 'ring trip next wknd will let you know if she's still in one piece

[appletree]

Tim the 32ft/lb +90 +90 is the specified ARP instructions that came with the studs, not the BMW spec 22ft/lb +90 +90ive done it now though there at the ARP spec and the last 60degrees went on suprisingly easily we'll see what happens

[tim_s]

Sweet! Well I'm sure it'll be fine, roughly what torque did that equate to in the end dude? You got ARP rod bolts and what did you give them or did the engine builder do it?

[appletree]

So my cars booked in with dave walker at Emerald to be remapped for this ne engine on the 28th of may, which as of friday would give me two weeks to get the engines swopped and put 500miles on it before it goes anywere the rolling road.

Managed to get all my ork finished early on thursday so i decided to book friday, saturday and sunday off and started stripping the engine ith the intension of lifting the engine out on friday and then fitting the new lump over the weekend, hwever i got on that well on thursday that i decided i would have a big push and try and get the engine out thursday night.

Few pics of the removal.

Last pic of the old engine in the bay with a spare cam cover as the nice one is on the new engine.



All ancillerys removed



Engine care read to lift out the old engine, propper engine hoist borrowed from work, usualy used for lifting cranks that weigh more than this engine.



Ready to lift



Still on the orgional clutch 2/7/90. 90,000 miles and now running nearly double the torque of the standard engine.



Out she comes, big thanks to Tim for coming round to help me with the lift.



Ready to lowered on to the engine stand to be rebuilt/stord or what ever, notice the exhaust manifold had cracked on the front cylinder which is pritty common on the M42 making the tell tail tickity sound, like injectors but its not, hopefully the new lump will be nice and quite.



That was the end of Thursdays work, pritty pleased with that. roll on friday

So yesterday was the day get the new lump in, this time i'd have to do it on my own as there wasnt anyone about to help, god did i struggle getting the spigot shaft to go in to the bearing what a shelag of a job that was!!

New lump on the stand ready to be craned in.



Just about to go in.



Touch down!! its in!!



Spent the rest of the day rebuilding up the ancillerys and the bay, it now runs with good oil pressure quitely and is bleed with coolent.

just need to get the trims, grills and a new power steering belt then shes ready for a first outing.

its also running abit rich at the minute but i think this may be because ive had the throttle cable off and havent reset the "zero" so it thinks the throttle is partly open when its not adding to much fuel.

[appletree]

Sweet! Well I'm sure it'll be fine, roughly what torque did that equate to in the end dude? You got ARP rod bolts and what did you give them or did the engine builder do it?

Not sure what the exact final torque was as i used a long braker bar for the last 60degrees as i was doing it on my own and struggling to see the gauge, tighten the nuts and stop the engine obbling on the stand. i've got ARP rod bolts and Main studs, the engine builder did the rod bolts and i did the main studs to 60ft/lb then undid them 1/4 turn and re torqued them ith plenty of ARP moly slip on them they went up nice and equal.

[rix313]

[appletree]

First 100miles under its belt now, slight teething problems with the throttle position switch pulling a wire out making a missfire occur when you accelerated or went over bumps. Sorted that now so just another 400 miles to go before Monday night.

[stonesie]

Nice weather for 'Random drives' too

Epic build