could I get some HP ideas from this group?

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bgriff
Posts: 50
Joined: Sat Nov 07, 2009 4:02 pm
Location: Wilmington, NC

could I get some HP ideas from this group?

Post by bgriff »

Hey guys, I'm going to do something soon to my '79 633 and I'm short on ideas. I know I want to switch the tranny from the original 4 speed to a 5 speed overdrive and I also want to get another 50-60 HP out of my original engine. I need to stay within $4000-4500.00 with someone else doing all the work since I'm a lousy mechanic. I've thought about switching the motor to a M30B35 out of a later e34, but I'd like to stick to my original engine if I can....would rather not do a rebuild and I don't want to turbo it. Am I being realistic at all? I appreciate any ideas.


Bob G
e12 based '79 6er
'85 6er 5sp
'85 6er Auto
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Mike W.
Posts: 2782
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Post by Mike W. »

HP does not come cheap for M30s. Especially if someone else is doing the work. You are at about 173. Later 3.3 pistons with higher compression would get you up to 180 or so. High compression pistons, custom and a big cam would get up up towards 200. But a late M30B35 is 208 stock. Still not the 230 you're looking for. Metric Mechanic engines, if they still make them, are regarded as wildly overrated and might get you in that neighborhood. Their sport engine is rated at 270, but no dyno sheets have even been seen, and that's $7k, without core, without shipping and without installation. In other words, $10 minimum to be running with a shop doing the work. Turbo has it's own set of challenges, but really is the cheapest way for a big HP bump.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
bgriff
Posts: 50
Joined: Sat Nov 07, 2009 4:02 pm
Location: Wilmington, NC

could I get some HP ideas

Post by bgriff »

Mike, I think you're right....it may not be realistic to limit the spend to $4-4500....now I'm thinkin maybe a M30B35 swap with possible upgrades, that would top out at maybe $5-6000....A 5-speed tranny swap will help too. Thanks for the input.


Bob G
e12 based '79 6er
'85 6er 5sp
'85 6er Auto
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