Rebuilding an m20b25. Got questions.

M20/M30/M50/Whatever! All engine related stuff here.
toointoxicated62
I <3 E30's
Posts: 379
Joined: Sun Aug 29, 2010 5:26 pm
AntiSpam: No

Re: Rebuilding an m20b25. Got questions.

Postby toointoxicated62 » Thu Feb 09, 2012 2:38 am

already plan on doing so
Image
User avatar
M20_fever
Größter Vorsitzender
Posts: 11029
Joined: Fri Feb 27, 2009 1:28 pm
AntiSpam: No
Location: Northern IL

Re: Rebuilding an m20b25. Got questions.

Postby M20_fever » Thu Feb 09, 2012 2:59 am

Also, of.you plan to boost now is a great time to.get the block oringed.
Image
Midwestern Councel C Prepared class champion 2012
North Suburban Sports Car Club C Prepared class champion 2012
HSAX Instructor

GET YOUR E3P GEAR HERE: http://www.cafepress.com/e3pgearshop
toointoxicated62
I <3 E30's
Posts: 379
Joined: Sun Aug 29, 2010 5:26 pm
AntiSpam: No

Re: Rebuilding an m20b25. Got questions.

Postby toointoxicated62 » Thu Feb 09, 2012 3:07 am

I plan on running 12 pounds max on an oem bmw head gasket. You really think its necessary?
Image
User avatar
M20_fever
Größter Vorsitzender
Posts: 11029
Joined: Fri Feb 27, 2009 1:28 pm
AntiSpam: No
Location: Northern IL

Re: Rebuilding an m20b25. Got questions.

Postby M20_fever » Thu Feb 09, 2012 3:17 am

No, its not a must have, but if you ever decide to go bigger it will be real nice having that already done. If you don't do the block now you will end up having the head oringed instead since I did it after the short block was together. Nothing wrong with that, other than having to do it again if the head ever gets trashed.

Are you getting head studs?
Image
Midwestern Councel C Prepared class champion 2012
North Suburban Sports Car Club C Prepared class champion 2012
HSAX Instructor

GET YOUR E3P GEAR HERE: http://www.cafepress.com/e3pgearshop
toointoxicated62
I <3 E30's
Posts: 379
Joined: Sun Aug 29, 2010 5:26 pm
AntiSpam: No

Re: Rebuilding an m20b25. Got questions.

Postby toointoxicated62 » Thu Feb 09, 2012 3:24 am

Will be running arp studs when boosted.


I will run it N/A for a bit before jumping into boost.
Image
User avatar
M20_fever
Größter Vorsitzender
Posts: 11029
Joined: Fri Feb 27, 2009 1:28 pm
AntiSpam: No
Location: Northern IL

Re: Rebuilding an m20b25. Got questions.

Postby M20_fever » Thu Feb 09, 2012 3:39 am

Its not a bad idea. Been running mine na for a.couple seasons now, should be boosting this fall.
Image
Midwestern Councel C Prepared class champion 2012
North Suburban Sports Car Club C Prepared class champion 2012
HSAX Instructor

GET YOUR E3P GEAR HERE: http://www.cafepress.com/e3pgearshop
Dontrusthise30
I <3 E30's
Posts: 374
Joined: Thu Dec 01, 2011 10:08 pm
AntiSpam: No
Location: Manistee, MI

Re: Rebuilding an m20b25. Got questions.

Postby Dontrusthise30 » Thu Feb 09, 2012 10:30 pm

I would recommend o-ring the block for a couple reasons. 1- you can do it for 60 bucks with the groove o matic. 2- I'm running 15psi and it's getting slow fast. I just want more. You're going to feel that way about 12 psi too. 12 is fun, but if you o-ring it you can just as easily run 20.
User avatar
ss45466
I <3 E30's
Posts: 645
Joined: Tue Feb 01, 2011 2:50 pm
AntiSpam: No
Location: S.F. NM
Contact:

Re: Rebuilding an m20b25. Got questions.

Postby ss45466 » Thu Feb 09, 2012 11:52 pm

I would also recommend o-ringing the block, I blew a goetze HG on my new engine after the break-in period when I started to turn the boost back up to where I was before. I o-ringed the block with it in the car, was pretty easy with the groove-o-matic from isky. I made some short handles for the #6 cyl with some 3/8ths all thread. Holding fine with a stock goetze Hg, arp's and o-rings @ 25psi. It's all posted in my build thread if you need more info.
toointoxicated62
I <3 E30's
Posts: 379
Joined: Sun Aug 29, 2010 5:26 pm
AntiSpam: No

Re: Rebuilding an m20b25. Got questions.

Postby toointoxicated62 » Fri Feb 10, 2012 12:18 am

ill speak with my machinist. If he will do it for a decent price ill do it
Image
toointoxicated62
I <3 E30's
Posts: 379
Joined: Sun Aug 29, 2010 5:26 pm
AntiSpam: No

Re: Rebuilding an m20b25. Got questions.

Postby toointoxicated62 » Sat Feb 18, 2012 9:15 pm

machinist wants 200 to o-ring the block o.O I think i will just rent the tool.

I had the engine honed and hot tanked for $125. Decked to clean up the little rust for 150$ and to install the intermediate shaft bearings for 25$.

He looked over my crank and said it checked out good. He mentioned that i should have it polished; is that worth it? He want 45$ for that.
Image
User avatar
M20_fever
Größter Vorsitzender
Posts: 11029
Joined: Fri Feb 27, 2009 1:28 pm
AntiSpam: No
Location: Northern IL

Re: Rebuilding an m20b25. Got questions.

Postby M20_fever » Sat Feb 18, 2012 11:41 pm

can't hurt, $45 isn't bad if it needs it.
Image
Midwestern Councel C Prepared class champion 2012
North Suburban Sports Car Club C Prepared class champion 2012
HSAX Instructor

GET YOUR E3P GEAR HERE: http://www.cafepress.com/e3pgearshop
toointoxicated62
I <3 E30's
Posts: 379
Joined: Sun Aug 29, 2010 5:26 pm
AntiSpam: No

Re: Rebuilding an m20b25. Got questions.

Postby toointoxicated62 » Wed Feb 22, 2012 3:29 am

Told the machinist to polish the crank. Ordered the intermediate shaft bearing yesterday, stealership told me i should have them tomorrow.

Will drop them off at the machinist and hopefully have the bottom end back this week.


I noticed that the original pistons have some scoring on it. Should i be worried? I have another bottom end with bad cylinder wall due to rust, i probably am going to pull the pistons and hope those are a bit better.
Image
User avatar
87e30
I <3 E30's
Posts: 2014
Joined: Wed Oct 27, 2010 5:25 pm
AntiSpam: No
Location: New Jersey

Re: Rebuilding an m20b25. Got questions.

Postby 87e30 » Wed Feb 22, 2012 4:36 am

$45 seems really good. I was quoted around $150 to polish the crank for my Chevy 350. Either your guy is really cheap, or my place is really expensive.
Schwarz 5-speed 87 325is (newest project)
Arktisblau 5-speed 86 325e (current DD)
Schwarz 5-speed 87 325e (parts car/LS1 swap?)
Gazellenbeige automatic 85 318i (70,000 miles)
Alpine white 5-speed 87 325is (my first e30, possibly for sale)
99 Suburban
toointoxicated62
I <3 E30's
Posts: 379
Joined: Sun Aug 29, 2010 5:26 pm
AntiSpam: No

Re: Rebuilding an m20b25. Got questions.

Postby toointoxicated62 » Wed Feb 22, 2012 9:38 pm

Not sure, i posted the prices for the other stuff that is getting done, compare those.


I picked up the bearings today, dropped them off at the machine stop. Should be done tomorrow
Image
User avatar
87e30
I <3 E30's
Posts: 2014
Joined: Wed Oct 27, 2010 5:25 pm
AntiSpam: No
Location: New Jersey

Re: Rebuilding an m20b25. Got questions.

Postby 87e30 » Wed Feb 22, 2012 10:28 pm

I have nothing else to compare them to at the moment. I only got the 1 quote when my 350 blew. I bought a new crank (new old stock) because it ended up costing me half of what polishing one would cost from this guy.
Schwarz 5-speed 87 325is (newest project)
Arktisblau 5-speed 86 325e (current DD)
Schwarz 5-speed 87 325e (parts car/LS1 swap?)
Gazellenbeige automatic 85 318i (70,000 miles)
Alpine white 5-speed 87 325is (my first e30, possibly for sale)
99 Suburban

Return to “Engine”

Who is online

Users browsing this forum: Bing [Bot], Google [Bot] and 2 guests