M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => Swaps, Turbos, Buildups => Topic started by: unome on November 13, 2011, 12:07:22 PM
-
Hi, has anyone documented a proper port and polish of an M42? Everyone has stroked or turbo'd or bored these engines, but I'm looking for whatever I can do basically for free. ( no, I'm not going to just start grinding)
I've read comments like "port aggressively" or "don't touch the ports" but nobody ever goes into detail. I know Metric Mechanic ports these with success but as you would expect, they share no details. Since I want to spend nothing, a MM head is not going to happen.
I've got a 318is E30 that is track-only, so streetability is not a concern. It will live at the red line. The entire car is brilliant on the track, so I'm not going to swap etc. but as long as I've got it apart I'd like to help it breathe a bit better. Specifics would be very appreciated!
Thanks
-
I have never seen anyone go past the "I was thinking about P&P for my M42, but I don't want to spend a bundle" stage. Perhaps you can be the first. I can say that MM claims a 6% gain in flow, "Our M42/M44 heads flow 6% over stock. These heads have our patented Surface Turbulence concentric grooves machined into the back side of the intake valve and the heads o both the intake and exhaust valves. This helps to reduce detonation in a boosted engine. It also helps prevent head cracking, increases fuel mileage and helps reduce emissions."
VAC has a picture of their stage 3 ports. http://store.vacmotorsports.com/vac---m42-stage-3-performance-cylinder-head-p1019c278.aspx?Thread=True (http://store.vacmotorsports.com/vac---m42-stage-3-performance-cylinder-head-p1019c278.aspx?Thread=True)
Perhaps the best thing to do on a budget is to make sure your intake runners, head to intake, and head to exhaust ports are close to matched as possible at home with no gasket overhang. In the end, although I base this on nothing more than personal feeling, I think there is nothing really useful to be gained from a P&P on the M42 without spending big bucks. Then again, on the track every single thousandth HP/lb/second counts.
Maybe you can find a ruined/cracked head locally and practice on that to see what you would like to change? Good luck however you proceed!
-
Yes, nobody seems to get past the "I'm going to do this" stage. Well, the motor is apart, and it's going to go back together, so we'll see what gets done to it. I'll report back, but in the meantime if anyone has done this before, I'd love to hear about it.
-
Look at my engine-in-build thread: Link (http://m42club.com/forums/showthread.php?t=8343). I have flow figures on the head before and after. The ports are 29mm although this maybe quite aggressive for a less experience engine porter.
-
Keep in mind that M50 ports are very similar, so what works for them can work here too.
Overall the M42 head is very decent flowing. Depending on what tools you have access to, you can do a multi-angle valve job.
Other than that you can blend the valve seat to the head casting better and remove the protruding valve guide material.
On most heads, blending the seat to the head, smoothing out the short radius, and removing/tapering the valve guides gets you majority of the gains.
-
I think with some effort bit of gains can be found without having deep understanding of porting.
(http://a4.sphotos.ak.fbcdn.net/photos-ak-snc1/v313/117/103/589403462/n589403462_776478_1282.jpg)
There is noticeable step where cast surface and machined surface meet on intake port. There is also small step between machined surface and valve seat. Also, combustion chamber can be blended more smoothly to valve seat, there is not some steps.
More involved is to remove valve guide that protrudes to intake port but that should yield nice gain.
I think I will try these basic things myself. Ports are quite generously sized compared to many other similar engines as they are.
-
Once I get home from my wedding/honeymoon in Thailand I will be finishing my M42 stroker. I ported the head myself with the watchful eye of my buddy who is a BMW Master Mechanic. Just to give you an idea of power, my S14 is making 320+HP on 11.25:1 compression that we built.
I changed my head to 6mm valves along with 33mm buckets!
The pic in the VAC ad is a S14 head.....
The MM head gains 6% flow from changing over to 6mm valves from the 7mm ones. I have never seen or heard of any info that MM has ported a M42 head and stated any flow statistics. If they have done so, I would love to see it, I'm curious.
"The Power is in the Head"!! Port it and have fun. Not rocket science. There's a lot of meat to remove in there. I think I must have spent 4-5 hours porting mine. NO polishing Required. It's a myth. Just port it. I'll have pics and a write up when I get back home. Porting also gains you torque down low, just don't go overboard on cams unless of course like you said it will stay at redline. The engine only breathes if all components work together. Open the ports, ditch AFM, increase compression, increase cam duration, increase exhaust flow.
Have fun with it. Mark D or Midnight can tune a chip for you or go stand alone.
Lots you can do and have fun at the same time!
Cheers,
~Ralph
-
Thanks for the replies! Lots of food for thought...
-
I would be careful here. When dealing with older designs it's easy to make improvments by using your eye and motor theory, but working with something as modern as an M42 it's very possible to make it worse not better.
If it were me and I wasn't paying someone with vast experience with these heads, I would go for the thinner valve stems and try to taper the guides a bit. Then maybe smooth out any irregularities.
If MM is getting a 6% improvement with all their resources, I'm sure the potential to do harm is high.
John
-
John, MM gets 6% increase in flow from only changing over to the 6mm valves and guides. Stock M42 before '93 was 7mm. They never mention head porting whatsoever.....so the potential is very significant! More air+ more fuel= More power.....
As long as you compliment all the parts, cams, head, intake, fuel, exhaust, bore, stroke, and engine management, you will always make more power than stock.
I just met with a master mechanic here in Thailand that worked for Schnitzer. I saw M42's making 300+ HP with slide throttles and carbon air boxes running 8 inj's etc.....he showed me the ported heads!
I will be getting a complete set of the intake from the air box to the head. I might be making up sets if people are interested. These kits are very "street able" and run perfectly. These are replicas of the original Motorsport ones. So there is a lot of potential even for street cars not just race cars. But for race cars....it's awesome when you get all the parts right!
Cheers,
Ralph
-
Ralph, no pictures? Come on!
Excited to see your setup!
For what its worth, I don't think there is a ton to be gained from head porting with the stock ECU. I really think you need larger cams and ECU tuning to make much of it.
-
Yeah I had no camera can you frigging believe it!!
Yes you're correct in needing to retune a chip if you port the head and change cams. That's if you want full potential.
I'll be running the Dbilas setup for a bit until I get the ore setup sent to me. It's very cool!!
Cheers,
Ralph
-
I'll be running the Dbilas setup for a bit until I get the ore setup sent to me. It's very cool!!
care to share the details of this "ore setup"?
-
Yeah I had no camera can you frigging believe it!!
Yes you're correct in needing to retune a chip if you port the head and change cams. That's if you want full potential.
I'll be running the Dbilas setup for a bit until I get the ore setup sent to me. It's very cool!!
Cheers,
Ralph
If that Dbilas set needs a home when you get your new kit, let me know. I would absolutely love a set of individual throttle bodies. :D
-
That was "other" set up....sorry
The other setup is the Motorsport one that you've all seen in the pics for the S42. Carbon fiber airbox with arihorns and 8 inj's, slide throttles, and intake adapters to the head.
When I get ready to get rid of the Dbilas, I will keep you in mind.
Cheers,
~Ralph
-
just gotta throw you're money in everyone's face... snooty jerk. j/k :)
PS, i'm gonna snag an M47 crank while I'm here and I figured out which rods MM uses for their builds (off-the-shelf, acura). put that in your pipe
-
I know that I've posted my build briefly somewhere. I already told everyone that the 138mm rod from a B18C (GSR) is the one to use because of an almost direct fit, BUT you have to rebush the small end because it's only 21mm not 22mm hence the reason that MM uses a custom piston with 21mm piston pin. I got mine from a very reputable source Nick Arias.
http://www.atomicspeedware.com/b18c1gsrvtec.aspx
How's that? Anything else you'd like to know?:D I have no secrets about this stuff. I want everyone running strokers with Carbon airboxes and having tons of fun!! I don't have the details yet but I was told from the guy in Thailand that the best piston to use is the Toyota 2J? I have to look into it.
Cheers,
~Ralph
-
Just for the record, I hate liking you :)
-
Hahahahaha. Yeah...I'm a likable person if you get to know me. I just got home from Thailand last night. I have not seen my car yet to see if my E30M3 exhaust with custom header from 666 Fabrication was finished. I will start a new thread and post all the goodies. However I can't post pics here so I'll work with Denis or someone to help me with that......
Until the next post......
FYI... did you know that you can adapt the 33mm cam trays from the E36M3 to work on our heads? hahahahaha........
Cheers,
~Ralph
-
Hahahahaha. Yeah...I'm a likable person if you get to know me. I just got home from Thailand last night. I have not seen my car yet to see if my E30M3 exhaust with custom header from 666 Fabrication was finished. I will start a new thread and post all the goodies. However I can't post pics here so I'll work with Denis or someone to help me with that......
Until the next post......
FYI... did you know that you can adapt the 33mm cam trays from the E36M3 to work on our heads? hahahahaha........
Cheers,
~Ralph
Ralph, I look forward to the next instalment from you. :)
David
-
I think with some effort bit of gains can be found without having deep understanding of porting.
(http://a4.sphotos.ak.fbcdn.net/photos-ak-snc1/v313/117/103/589403462/n589403462_776478_1282.jpg)
More involved is to remove valve guide that protrudes to intake port but that should yield nice gain.
.
I just tried this today. It isn't as hard as you think. One tip I heard from a pro head porter was to hone out the bore of the guide to just above the port roof before grinding down the guide. Soooo, since I have a free bare head to practice on, I took a slightly larger drill bit that the valve stem diameter, I drilled down about a 1/2" very slowly. Then I ground down the rest of the guide 'till it was flush with the port roof. Doing it this way means the valve is not pushed sideways by a guide only touching it on one side. Does any of that make sense? Either way it seems to have opened up the bowl area nicely. I do not feel confident enough with my skills to really open up the ports. The head is at work so I cant take a pic at the moment.
-
FYI... did you know that you can adapt the 33mm cam trays from the E36M3 to work on our heads? hahahahaha........
Cheers,
~Ralph
what's the benefit of running these cam trays?
-
33mm buckets....lighter vs the heavier 35mm stock or M5X
Ralph
-
what's the weight on those? lighter than the VW lifters?
-
That was my next question
-
i just bought a set of vw lifters so i guess i'll be sticking with the stock trays. does anyone have actual weights of the different lifters available? i tried to weigh my stock lifters but they had some oil inside so i don't think it was accurate, just over 70 grams i think. i'll be measuring the vw lifters when i install them but they're staying sealed up and safe for now.
-
44gms vs 53gms for VW.
WEIGHT SAVINGS
My valve train saves you 1,297 grams or 2.86 lbs over stock. 488 grams or 1.08 lbs over the 35mm lightened setup.:D
~Ralph
-
44gms vs 53gms for VW.
WEIGHT SAVINGS
My valve train saves you 1,328 grams or 2.93 lbs over stock. 848gms or 1.87lbs over the 35mm lightened setup.:D
~Ralph
Alright ralph, time for a write up. I'll have another M42 to play with once I swap in the one I just finished. Damn you. Are the M42 cams retained?
(I'd really like to build an M42 turbo touring with an M47 crank :))
-
where does all the extra weight savings come from? actual lifter weight savings is only 250g over stock, 150 over the VW lifters.
m42 - 65x16= 1040
vw - 53x16= 848
33mm - 44x16= 704
-
Does it have to be a M3 cam tray? or will other M5X cam trays work? I assume the M3 is recomended because it already has solid lifters? If so solid lifter conversions for M5X heads are readily available and would negate the need to track down a rare M3 head.
-
MLM:
They have to be M3 cam trays because the M5X trays are 35mm.
These are still hydraulic not solid.
Yes you can keep the M42 cams. I had custom cams cut that are only 250's but more aggressive than the Schricks.
My Math was wrong the first time and I will go back and change that post.
This is what I measured on a scale:
Lifter Bucket:
M42/S50 M42 Light M42 Stock
33mm= 44.0gms 35mm= 64.5gms 35mm= 77.09gms
44x16=704gms 64.5x16=1,032gms 77.09x16=1,233gms
Keeper:
M42/S50 M42 Light M42 Stock
1.0gms 1.0gms 2.5gms
1x16=16gms 1x16=16gms 2.5x16=40gms
Retainers:
M42/S50 M42 Light M42 Stock
8.0gms 10.0gms 19.0gms
8x16=128gms 10x16=160gms 19x16=304gms
Springs:
M42/S50 M42 Light M42 Stock
Beehive= 37.0gms Beehive= 45.0gms Dual Spring=62.0gms
37x16=592gms 45x16=720gms 62x16=992gms
Intake Valve: (x8)
M42/S50 M42 Light M42 Stock
33mm= 45.5gms 33mm= 45.5gms 33mm= 58.5gms
45.5x8=364gms 45.5x8=364gms 58.5x8=468gms
Exhaust Valve: (x8)
M42/S50 M42 Light M42 Stock
30.5mm= 46.0gms 30.5mm= 46.0gms 30.5mm= 54gms
46x8=368gms 46x8=368gms 54x8=432gms
Total:
S50 Light M42 Light M42 Stock
2,172 grams 2,660 grams 3,469grams
4.79 lbs 5.86 lbs 7.65 lbs
S50: Save 1,297 grams or 2.86 lbs of Total Valve Train Mass over stock.
S50: Save 488 grams or 1.08 lbs of Total Valve Train Mass over the M42 Light.
M5X: Save 809 grams or 1.78 lbs of Total Valve Train Mass over stock.
-
Hope all of you can decifer the text because it didn't look like that when I sent it...LOL
Just read it across from S50.........to M42 Light........to M42 Stock
Ralph
-
Thanks for the info, Ralph! So the 'M42 light' setup are all M5x parts?
I already have a rebuilt head so I guess all I can do at this point are the lifter buckets. :/
-
Yes the M42 Light set is all M5x parts... though the valves and keepers are the same as the S50.
Well that all depends on what you want to do... You can change to lighter lifters and change your springs too but that also means your retainers as well because that is what your spring sits on and is held in with the keepers.
~Ralph
-
I have not seen my car yet to see if my E30M3 exhaust with custom header from 666 Fabrication was finished. I will start a new thread and post all the goodies. However I can't post pics here so I'll work with Denis or someone to help me with that......
Until the next post......
FYI... did you know that you can adapt the 33mm cam trays from the E36M3 to work on our heads? hahahahaha........
Ralph, I can host pictures for you :)
Good to know on the 33mm e36M3(US) cam trays can work. I never thought of that but it makes total sense if you shorten them. If you wanted to go solid lifters, there are a lot of options out there for that.
I read recently that the M50tu lifters are lighter than our lifters and a re a direct replacement. I have not verified this myself though.
I want to get a VW lifter and take it apart and compare to the BMW unit. I have worked on many VWs and generally I think they are cheap cars. If there was easy weight savings to be had by using an off the shelf lifter I am sure BMW would have done so. I question whether the VW lifter is up to task as much as the BMW unit. Only a side by side comparison can show the difference.
-
The VW and BMW lifters were both made by INA, save your time.
The VW/M52 lifters are 49 grams, so x16 that's 80 grams or 2.82 ounces or .176 pounds more than the S50's. I'll stick with the drop in lifters and not bother with trying to source M3 cam trays that have to be modified to fit. Good info all around tho ;)
There has been some talk about using 49 g hydraulic lifters from some VW models to lighten the valvetrain.
I happened to notice from internet ETK that BMW also uses 49 g lifters on M52 engines!
I did bit of calculations (found useful equation from a book I have) and valvetrain (lifter, spring, spring plate, valve, collet) would be about 10% lighter with 49 g lifter compared to standard 67 gr lifter. That means that everything else staying as it is, engine rev limiter could be safely raised from 6800 to 7200 rpm.
M52 engine does have other interesting parts too... Spring plate is 2 g lighter (8 vs 10) and spring itself is whopping 13 g lighter (38 vs 51).
If those parts would be used on M42, valvetrain mass would be 18,8% lighter which means safe rpm goes from 6800 to 7550. That is of course in case that lighter M52 spring has same spring rate as standard M42 spring. I somehow doubt this as I suspect that BMW just optimized valve train power loss by using softer springs (hence their lower weight) made possible by lower lifter and valve plate masses.
Anyone know actual spring rates of standard BMW springs? Or Dbilas or Shrick springs? Lighter M52 lifter and 20% stiffer springs would guarantee happy revving all the way up to 8000 rpm :)
And your math is off a bit Ralph. You didn't separate the different weights of the in/ex valves so really it's:
M42/S50 = 2,172g = 4.788lbs
M42 Light/VW = 2,252g = 4.964lbs
M42 Light = 2,660g = 5.864lbs
M42 Stock = 3,470g = 7.650lbs
Best answer, get an M42 head from 9/1992 or later and add VW/M52 lifters.
http://www.realoem.com/bmw/showparts.do?model=BE53&mospid=47480&btnr=11_1143&hg=11&fg=25
I question whether the VW lifter is up to task as much as the BMW unit. Only a side by side comparison can show the difference.
:)
(http://i796.photobucket.com/albums/yy249/bwawuz02/car%20stuff/IMG_1338.jpg)
(http://i796.photobucket.com/albums/yy249/bwawuz02/car%20stuff/IMG_1332.jpg)
-
bwawuz02.....my calcs were done with 6mm valves for the S50 and M42 Light.
I used MM's info plus what I measured myself. Not sure what you mean about the valves. There is a difference between the 6mm and 7mm.
You also have to remember that there is a bigger difference in spring weights!!
Cheers,
~Ralph
-
I know the 6/7mm valves are different, that's why I got a 95 318ti engine for my build :) you added the weight of each valve-train component together and multiplied by 16, but there are only 8 intake and 8 exhaust valves. look at it again, you'll see it. I noticed it when I was comparing your numbers to MM's brochure, which lists theirs at 166 grams per valve. Your numbers add in 8 extra intake and 8 extra exhaust valves.
My name is Jesse, btw.
-
Jesse,
I guess we have a whole new car if we get 32 valves don't we??:D
I will look at that and change the math again........
Thanks for the heads up dude.
~Ralph
-
Question...
Is the purpose of these lightweight parts to reduce valve / valvetrain float, and to ultimately allow a higher redline?
If so, how high? What would cam specs look like up there?
-
Yes it might reduce valve float but I'm not sure how high you can go with the hydraulics. I've heard of 7500rpm all day long, MM supposedly goes 7700rpm but you can definitely can go higher with solid lifters.
Cam specs are all dependent on what you want to do with the engine. Race, street, etc... I went 250/250 with 10.4mm lift but its more aggressive than the Schrick 256's.
You can go balls to the wall with cams and have a high peak HP number but be a dog down low or you can make your cams be more moderate and get tons of down low grunt with a nice pull to 7500-7800rpm all day long. That's what I did with the 250/250 combo.
Cheers,
~Ralph
-
who did the cams for you ralph?
-
Dick Chiang at Dynospot Racing
http://www.dynospotracing.com/index.html
~R
-
I have some old reground delta cams 272deg (not made anymore). They are better than stock, but they are a sacrifice with higher duration and not much more lift.
I would much rather run some real custom cams. VAC sells different grinds as well as Catcams cams. Billet cams are going to be a much better way to go.
Web cams in California also has a lot of grinds. They do the MM cams from what I hear.
-
:)
(http://i796.photobucket.com/albums/yy249/bwawuz02/car%20stuff/IMG_1338.jpg)
(http://i796.photobucket.com/albums/yy249/bwawuz02/car%20stuff/IMG_1332.jpg)
Wow, thanks!
-
the dyno chart at the bottom of this page make me very optimistic for my build to dyno 160-170 at the wheels. Considering my displacement is equivalent sans 2 cylinders and i'll be running the ITBs :) If I can put 170hp to the wheels at 6k rpm I'll be screaming joy all the way to 7.8krpm. If my mystery spec regrinds don't do the trick I'm either gonna copy cat ralph or possibly pick up CatCams.
http://dynospotracing.com/charts/E36_M3_95DSR.html
-
Very interesting. Subscribed. I'm in for the specs and pics of the new intake. I'm still collecting parts, info, and $$ for my stroker build.
-
This is what I measured on a scale:
Lifter Bucket:
M42/S50 M42 Light M42 Stock
33mm= 44.0gms 35mm= 64.5gms 35mm= 77.09gms
44x16=704gms 64.5x16=1,032gms 77.09x16=1,233gms
Keeper:
M42/S50 M42 Light M42 Stock
1.0gms 1.0gms 2.5gms
1x16=16gms 1x16=16gms 2.5x16=40gms
Retainers:
M42/S50 M42 Light M42 Stock
8.0gms 10.0gms 19.0gms
8x16=128gms 10x16=160gms 19x16=304gms
Springs:
M42/S50 M42 Light M42 Stock
Beehive= 37.0gms Beehive= 45.0gms Dual Spring=62.0gms
37x16=592gms 45x16=720gms 62x16=992gms
Intake Valve: (x8)
M42/S50 M42 Light M42 Stock
33mm= 45.5gms 33mm= 45.5gms 33mm= 58.5gms
45.5x8=364gms 45.5x8=364gms 58.5x8=468gms
Exhaust Valve: (x8)
M42/S50 M42 Light M42 Stock
30.5mm= 46.0gms 30.5mm= 46.0gms 30.5mm= 54gms
46x8=368gms 46x8=368gms 54x8=432gms
Total:
S50 Light M42 Light M42 Stock
2,172 grams 2,660 grams 3,469grams
4.79 lbs 5.86 lbs 7.65 lbs
S50: Save 1,297 grams or 2.86 lbs of Total Valve Train Mass over stock.
S50: Save 488 grams or 1.08 lbs of Total Valve Train Mass over the M42 Light.
M5X: Save 809 grams or 1.78 lbs of Total Valve Train Mass over stock.
I have changed and fixed the Math on page 2 and 3 (Thanks for pointing that out Jesse aka bwawuz02) in this thread and resurrected it since it might be beneficial to a few people building engines now ;D
And maybe one day we just might have a 32 valve M42 engine....LMAO
Cheers,
~Ralph
-
found something interesting on MM heads:
https://patents.google.com/patent/US4976248A/en (https://patents.google.com/patent/US4976248A/en)
-
found something interesting on MM heads:
https://patents.google.com/patent/US4976248A/en (https://patents.google.com/patent/US4976248A/en)
its a shame they never did anything to prove the merit. or perhaps they did tests and didnt want to publish results...
having used one of their complete heads i cant really say it performed any better than the tradiional approach.
personally i think the scale and size of the features is too large, a rough texture (burr finish or extremely coarse grit) can be good for wet flow and even dry in some cases this has been tested but you dont reallly need large steps which have the issue of creating dead pockets and hot spots within the chamber...