Another M42 engine build

[wazzu70]

I am envious of your parts order! The Pauter rods are very nice! The pistons sound great too. Nothing wrong with leaving some more meat on the cylinder walls. Going too big a bore can cause problems with thin spots.

Are you planning on using the stock flywheel? I would seriously recommend upgrading to a lighter weight unit as it made a huge difference on my car.

Honestly, the stock M42 cams are pretty pathetic and are built for economy more than any performance. Some street upgrade cams will still keep near stock drivability and have a lot more potential. Something like the VAC 269/269 would be perfect IMO.

[Warsteiner]

Thanks wazzu70 & Warsteiner.  I did know about turning the snout down and the required keyway, but not the bolt or spacer.  Do you have any specs?

NO worries.....I'm glad to see more people are going for it.  Here is the info for the bolt and spacer. I will give credit where credit is due.....If he's still on the list, the bolt goes to Lund8200's.

I developed the spacer myself.

New Crank spacer 20.35mm
old crank spacer 13.9mm
thread length 37mm(You have to cut the bolt)

Cheers,
~Ralph

[Warsteiner]

Which way would you go?

1) given the crank looks good-simply go up one size on pistons, keep stock m42 crank and put money into head and cams? What cam specs don't know.

2) M47 crank, keep stock rods, custom JE pistons, re grind cams probably to Warsteiner's 250/250.  I think I'd sacrifice a bit of displacement and only go 85 and preserve some meat for a later day.

I'm leaning towards #2 for a couple of reasons.  Take care of the bottom end now while its out and apart, head can be reworked later if results aren't satisfactory.  It would be a reverse build from what i8ur911 is doing (I think he's doing more #1).

Am I being penny wise and pound foolish for keeping stock rods?

I look forward to your thoughts.

Number 2 is a great option!!  The 250* cams are more aggressive than the Schrick 256* at .050" with 222 degrees vs Schrick with 215 degrees. That little bit of boring will not make a big difference in displacement. Definitely port the head!!

Cheers,
~Ralph

[Warsteiner]

Crank order looks like it went through so I went ahead and got the pistons ordered.  I ordered pistons and rods from Steve at top end racing, nice guy .  Went with JE 85.0mm with 28.15 CH shooting for CR of 10.8/1.  I went 85mm bore to preserve future upgrade/maintenece options, I know the restraint was amazing .  I went ahead and ordered new rods too, wazzu70's words seemed wise so upgraded those to Pauter 140mm. 

The head pressure tested okay and was only out .0015 inches from flat.  I think I'm going to have the head freshened up at the local machine shop although Korman is working up a quote for me too.  Steve  at top end suggested running with stock cams and see how we like it.  I'm not opposed to dropping new cams or leaving the old.  I just don't want to lose the bottom end the M47 will theoretically give us.  The goal here is just a fun extremely streetable ride not maxing out the dyno or a screaming track rat, but at the same time I don't want to leave fun usable power on the table given everything else we're doing.  Does that make sense?  Anyway, I'm very intersested in your opinions on this.

Let tme know what you think about the head.

I think the Pauter rods are awesome!! I spoke with Steve years ago about the pistons as well and we came up with 28.15mm for 140mm rods as well and he was ok with that.

It looks like you will have about the same engine specs as I do. Barrie can tune a chip or you can go with MSII and I can give you my file. I'm running ITB's and bigger M42 header with E30M3 exhaust. Also 24lb inj's.

Port the head! Hahaha

Cheers,
~Ralph

[dsm2002]

Thanks wazzu70 & Warsteiner.  I did know about turning the snout down and the required keyway, but not the bolt or spacer.  Do you have any specs?

NO worries.....I'm glad to see more people are going for it.  Here is the info for the bolt and spacer. I will give credit where credit is due.....If he's still on the list, the bolt goes to Lund8200's.

I developed the spacer myself.

New Crank spacer 20.35mm
old crank spacer 13.9mm
thread length 37mm(You have to cut the bolt)

Cheers,
~Ralph

Thanks Ralph. I did not pick up on the crank spacer and bolt during my readings.  Is the spacer shown on the left of the Febi's photo with the bolt and hub?

[Warsteiner]

Yes. I had one custom machined that is stepped and fits perfectly.

Cheers,
~Ralph

[Gerta318is]

If you are not opposed to spending a little dough on the M42 Non-AC flywheel you can get that from Germany.  I ordered mine through Steve at Blunttech.com.  Ive go my engine ready to go on a stand for this weekend so reading your thread makes me wish it was Friday night already!

[wazzu70]

I wish I had gone that route! Its all OEM and fits out of the box!

[Warsteiner]

I went the M20 route. Lightened it to 11 lbs if I recall and machined it to fit the M42 ring gear. Added a stock 325 228mm clutch kit and called it a day.
 

Cheers,
~Ralph

[mabeer]

Sub frame is out.  Now the question is do I stick with the 4.10lsd or drop in the 4.27lsd?  I picked up the 4.27 a while back after we put in a luke box, sub and amp.  That stuff is heavy, but sounds so good. 

[wazzu70]

For an atmo 1.8L I would say 4.27 without a doubt.

For your stroker build I would keep 4.10 since you will have more torque down low and its a street car. The higher gearing will be nice.

Swapping a differential is very easy. If you don't like the 4.10 you can step down to 4.27 or up to 3.73.

[mabeer]

Picked up the M47 crank today. 

[2002Harv]

Sweet little itty bitty baby Jesus!

John

[mabeer]

Time for some updates.  Most of the month of May has been spent waiting for parts.  UPS brought these today    I can get the pistons to the machine shop and they can get the block squared away.



The head is at Korman getting reworked.   I know Warsteiner says just get in there and start porting but I know I would screw it up.   I decided to go with Schrick 256/256 cams maybe low on the performance/$ value scale but one of the build goals is to keep it very streetable so mild it is.

A question, the decision to go with the Schricks came after the pistons were ordered.  Stock cams have a lift of 9.70mm, lift at TDC is .90mm intake and .65mm exhaust.  The shricks have 10.4mm lift and lift at TDC is 1.2mm intake and 1.2mm exhaust (if I'm reading their specs correctly).  Is there a way to calculate/measure if I need to have the valve reliefs increased in the piston tops before assembly or is the only way to do it by a test fitting?  Wish I would have had my ducks in a row before I ordered the pistons.  As always, your advice is appreciated.

[wazzu70]

Contact TEP and see if the valve reliefs are deeper than stock. Usually on aftermarket pistons they are.

I also believe the Schricks work with a factory motor, so you should be good either way. There is no replacement for actually measuring the clearance with some putty though!

Parts look beautiful.