Author Topic: m44/m42 spec rally engine (Read 56780 times)

jerseytim · « **Reply #60 on:** October 26, 2015, 01:12:43 AM »

hello sion
i looked into the s2000 gearbox and the ratios in the 328/m3 box seemed better and much easier to fit. i am still using the standard 318ti gearbox which i previously used with a 328 engine and it has been given some heavy abuse https://youtu.be/vldaFf5zwvU (skip the first 60 seconds as i got lost) but never given me any problems. i have a 2.1 m42 and have been told if i want to keep it safe i should limit the revs to 7000 as the longer stroke puts more strain on the rods and i am using the standard m42 rods. Is your engine going into a rally car?
good luck with your build
tim

sh123 · « **Reply #61 on:** October 26, 2015, 06:18:46 PM »

hi Tim,

We did speak on the bmw rallying forum a few weeks ago, not sure if you remember or not, I think I have the same username.

I think that the s2000 has closer ratios than the m3 6 speed hence why I was/am looking at going down this route. problem with the bmw 6 speed is its exactly the same ratios as I have now but with an overdrive. with the type of rallying I do a direct 5th and a 4.45 diff is ideal top speed, hence why im looking for a box with as close to a direct 5/6th as I can.

Bmw ratios: 4.35, 2.5, 1.66, 1.23, 1.00, 0.85
s2000 ratios: 3.634, 2.372, 1.718, 1.347, 1.126, 0.941

yes im keeping mine at 7000 i think, but the compact cup guys are running their standard m44's at 7200RPM

Not much news on the build side of things, just doing bits and bobs to the car. spoke to the guy who will be remapping it once its back running so that is all sorted. And spoke to the engine builder, said he was starting some point this week and he is going to concentrate on my build to get it done all at once.(rather than doing other builds as well)

jerseytim · « **Reply #62 on:** October 27, 2015, 05:24:52 AM »

your right, the s 2000 ratios do look better than the ones in the 328 box, they don't seem expensive at the moment either. I'm not sure i can face all the work involved with fitting the starter motor, clutch, bell housing and prop shaft.
a friend of mine has one off the car so i might go and have a look, do you know if it has been done before?

sh123 · « **Reply #63 on:** October 27, 2015, 11:53:34 AM »

Them ratios are for the first series of s2000 just so you know 2nd series is very similar however.

Yes it has been done i know of two. What needs doing is cutting the bellhousing in half the then transfers the mounts for the starter. Then you need a slave of a diesel vauxhall( i havent a part no yet) and then a honda accord 240mm clutch disc fitted to a m3 flywheel and cover plate. Quite simple really you just need to find an engineer to do the cutting and welding.i can send a few pics if needed.

sh123 · « **Reply #64 on:** November 07, 2015, 01:00:51 PM »

Hi

What affect would 35mm inlet valves and standard exhaust valves have on a m42? Ive asked my builder to get back to me on valves but doing a bit of reading. Have found that the Peugeot 206 gti180 inlets ar 6mm exact same length and 35mm. One peace uprated ones are about �20 each. Just got me wondering

sh123 · « **Reply #65 on:** November 07, 2015, 01:09:57 PM »

http://www.spoox.co.uk/en/919-valves?p=2

The exhaust valves of this engine wont work though as they are longer

Warsteiner · « **Reply #66 on:** November 07, 2015, 01:13:57 PM »

Scion,

In my opinion you need to be making over 250 crank HP before you consider moving up to bigger valves. Remember that everything has to work together. Valves are not a bolt on performance so I would concentrate on other areas.

Cheers,
~Ralph

sh123 · « **Reply #67 on:** November 07, 2015, 01:19:42 PM »

Hi Ralph.

Thats fair enough I was only looking as I know a lot of other engines which are used for competition usually have bigger valves than the m42/4. Such as whati just linked which are standard sized valves on a 2.0 with 180bhp factory.

Im not arguying as i havent really a clue what im talking about haha. But my head will be flow benchd etc and the cams will be specified by the builder so he will be making the final decisions.

Cheers
Sion

Warsteiner · « **Reply #68 on:** November 07, 2015, 01:30:30 PM »

Scion,

I'm just speaking from personal experience on the S14 where I still have the stock valves and am making 320+HP from a possible 380HP.

I can't wait to see what your builder comes up with. Are you allowed to port the head?

~Ralph

sh123 · « **Reply #69 on:** November 07, 2015, 01:42:46 PM »

Yes im having the head ported. Ive basically asked him to see what he reckons and get back to me with a price. Buts its being ported and cams atleast.

Im looking forward as well as he is very well known in the uk especially in the classic/competition ford scene. Ill post some links later of some of the engines hes built.

I rang him last week and he told me he was starting it last Wednesday /thursday and he was going to do it all at once. So hopefully it will be here soon!

wazzu70 · « **Reply #70 on:** November 08, 2015, 12:57:25 PM »

The size of valves to fit depends a lot on the bore size of the engine. An engine of equal displacement but larger bore can make use of bigger valves. The reason is the valves have more room to space out without being right up against the cylinder wall.

Bigger valves dont benefit if the flow from them interferes with the other valve flow!

sh123 · « **Reply #71 on:** November 09, 2015, 12:15:34 PM »

So the builder contacted me today. Hes stripped the engine given me a proper quote with parts etc now included. He is regrinding the standard cams for me. And for some reason exhaust valves need replacing i havent asked why yet but they were clogged up with black stuff when i looked so maybe they are pitted or something.

He says work is starting tomorrow and should be with me in 4 weeks!

Autotec.at · « **Reply #72 on:** November 16, 2015, 01:25:35 PM »

Hey guys,
i just read the complete threat and i�m fighting around with the same problem, i just building an M42 rally engine.
Setup so long:

M42 Head:
CNC machined and ported head, CNC machined combustion chambers, flowbench test, multi angle valve seat ring cut, new conical valve guides for 6mm valves, aso... (all done by NG Motorsport Germany)

Valves:
Supertech Inconel Valves, +1mm inlet and outlet,

Camshafts:
Catcams 1301520 Kit (298/290) including Follower, Lash Caps, upper and lower retainers & suitable uprated Springs (no more hydraulic lifters)

Pistons:
CP Forged Pistons, 11:1 Ratio

I'm not really sure if i should put all together in this configuration!? What do you think?
Crankshaft and Flywheel will be lightened and balanced for sure, even forged I or H Beam Conrods will be used.
But i'm struggeling with my head config.....
I have to mention that i'm not allowed (rally regulations) to use an ITB, for sure it will get an DTA ECU and will run on AlphaN.

Goal is an engine with an big usable rpm range, starting somewhere around 5000 till 8000rpm�s

Please help me and let me hear your ideas and proposals!

David

Darky · « **Reply #73 on:** November 16, 2015, 05:55:17 PM »

Hi

Sounds impressive but this is Sion's thread.
He has gone with 87mm pistons and 88 mm crank. Hint!!

Cheers Rohan

sh123 · « **Reply #74 on:** November 16, 2015, 07:14:49 PM »

Hi David,

Personally I am not the right person to give you advice on what spec to build your engine. I have sent my engine away to be built and spec'd by a engine builder, their are a few reasons for this:

Firstly I wasnt happy with building an m44 head as their wasnt much info out there on them, therfore I decided it was best for someone who had more experiance in building heads in general

If i would have built it myself i would have had the head built by one company and the block by an engineer. ....What happens if the engine goes bang?(which often happens in competition circumstances) who would I turn to if it blew up...Therfore if I was you I would go back to NG Motorsport and see what they think of your bottom end and what they can do.

Few pointers I would give on your build though, Im building mine for rallying but I was looking for torque as the rallying I do is very twisty and not suited for high revving engines, So hopefully with a 2.1 block and 12:1 compression I will see good torque. I belive if you kept to 1.8/9 you would have to rev it much harder which as you may know isnt always good for rallying and engine life.

Good luck with your build though
Sion

Author Topic: m44/m42 spec rally engine (Read 56780 times)

jerseytim

Re: m44/m42 spec rally engine

sh123

Re: m44/m42 spec rally engine

jerseytim

Re: m44/m42 spec rally engine

sh123

Re: m44/m42 spec rally engine

sh123

Re: m44/m42 spec rally engine

sh123

Re: m44/m42 spec rally engine

Warsteiner

Re: m44/m42 spec rally engine

sh123

Re: m44/m42 spec rally engine

Warsteiner

Re: m44/m42 spec rally engine

sh123

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wazzu70

Re: m44/m42 spec rally engine

sh123

Re: m44/m42 spec rally engine

Autotec.at

Re: m44/m42 spec rally engine

Darky

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sh123

Re: m44/m42 spec rally engine