boosting alloy blocks, whats the limit?

Moderator: martauto

Post Reply
User avatar
Coyote_ar
E30 Zone Newbie
E30 Zone Newbie
Posts: 108
Joined: Mon Jan 07, 2008 11:00 pm
Location: Argentina

Sun May 13, 2012 6:18 pm

Hi guys, do you guys have some info on how much power the alloy blocks will hold?

Lots of people say they wont hold much power, due to being alloy blocks, but couldnt find any case where the block failed to excesive power.

im aiming for 450-550hp on a M52TUB28 with forged pistons and rods. i want to know if the block will be an issue.

cheers.
User avatar
Gunni
E30 Zone Addict
E30 Zone Addict
Posts: 2115
Joined: Tue Jan 11, 2005 11:00 pm
Location: Oxford

Sun May 13, 2012 11:21 pm

I believe PPF in Sweden have seen 500whp.
With great challenges comes great engineering.

Gunni
@ 2012 VEMS group buy !!
User avatar
Coyote_ar
E30 Zone Newbie
E30 Zone Newbie
Posts: 108
Joined: Mon Jan 07, 2008 11:00 pm
Location: Argentina

Thu May 17, 2012 4:29 pm

been reading e46 forums, it would seem that the M52TU and M54 head/block are almost indentical, so using that as a reference 500-600hp has been done. Thats good enough for me, not planning on going further than that.
User avatar
redcar
E30 Zone Squatter
E30 Zone Squatter
Posts: 1610
Joined: Wed Jul 20, 2011 11:00 pm
Location: Hertfordshire

Thu May 17, 2012 6:15 pm

Coyote_ar wrote:Hi guys, do you guys have some info on how much power the alloy blocks will hold?

Lots of people say they wont hold much power, due to being alloy blocks, but couldnt find any case where the block failed to excesive power.

im aiming for 450-550hp on a M52TUB28 with forged pistons and rods. i want to know if the block will be an issue.

cheers.
Hi, i'm also confused by why people shy away from the alloy blocks when they want to boost. I couldn't find a case where a properly built alloy block m52 had caused damage to the block when being boosted.
An sr20 will do plenty of bhps and that's an alloy block and only 2.0L so has to cope with a fair bit of boost to get good powers through it.
Would be interesting to see a boosted m52 as it seems to be a really good engine. 2.8L and isn't silly heavy either.
ross_jsy
Married to the E30 Zone
Married to the E30 Zone
Posts: 7307
Joined: Sun Jul 12, 2009 11:00 pm
Location: Jersey, C.I.

Thu May 17, 2012 6:27 pm

It's more a case of if you get detonation-far easier on a boosted car weather it be poor mapping, poor fuel quality, running hot on track etc, then it can strip the head bolt threads which are a weak point on the m52.
User avatar
redcar
E30 Zone Squatter
E30 Zone Squatter
Posts: 1610
Joined: Wed Jul 20, 2011 11:00 pm
Location: Hertfordshire

Thu May 17, 2012 6:52 pm

ross_jsy wrote:It's more a case of if you get detonation-far easier on a boosted car weather it be poor mapping, poor fuel quality, running hot on track etc, then it can strip the head bolt threads which are a weak point on the m52.
I see, but with a good, reliable build i.e. proper engine management with continuous readings showing knock etc. this shouldn't really be a problem. Large intercooler, correct fuel and general sense of care towards the engine shouldn't really make this such a problem to actually avoid the m52 for turboing should it?

Cheers.
User avatar
Coyote_ar
E30 Zone Newbie
E30 Zone Newbie
Posts: 108
Joined: Mon Jan 07, 2008 11:00 pm
Location: Argentina

Fri May 18, 2012 5:53 pm

ross, yeah regarding the head bolts, i read that its a weak point on the M52s. they recommended to use arp studs instead of bolts.

aside from that, as redcar said, the other items you mention are just risks present in all boosted cars, alloy or not.
one thing i saw regarding M52TUs and i believe it also affects M6x, is that bmw choose to run those engines extremely hot to improve emissions, and that increases the risk of head warping and other nasties. i was thinking just changing the thermostat for a mechanical 85c one, or just keep the electronica one set to open at lower temp.
DanThe
E30 Zone Team Member
E30 Zone Team Member
Posts: 28641
Joined: Sat Sep 10, 2005 11:00 pm
Location: Staffs
Contact:

Fri May 18, 2012 6:10 pm

109° anyone? :eek:
e30-EVN
Old Skooler
Old Skooler
Posts: 3382
Joined: Sun Dec 13, 2009 11:00 pm
Location: S.Wales

Fri May 18, 2012 6:37 pm

why not run an 80-88 like us lot do?? :?

you dont want it to hot 8O
A 2 door e30 with 8 cylinders, what could be better winkeye :D
User avatar
redcar
E30 Zone Squatter
E30 Zone Squatter
Posts: 1610
Joined: Wed Jul 20, 2011 11:00 pm
Location: Hertfordshire

Fri May 18, 2012 7:02 pm

e30-dk wrote:why not run an 80-88 like us lot do?? :?

you dont want it to hot 8O
I think it's to improve economy. The m62 in the range rovers run at 100 + 8O
e30-EVN
Old Skooler
Old Skooler
Posts: 3382
Joined: Sun Dec 13, 2009 11:00 pm
Location: S.Wales

Fri May 18, 2012 7:13 pm

thats never a good thing surely 8O
A 2 door e30 with 8 cylinders, what could be better winkeye :D
User avatar
redcar
E30 Zone Squatter
E30 Zone Squatter
Posts: 1610
Joined: Wed Jul 20, 2011 11:00 pm
Location: Hertfordshire

Fri May 18, 2012 7:17 pm

e30-dk wrote:thats never a good thing surely 8O
Why not?
DanThe
E30 Zone Team Member
E30 Zone Team Member
Posts: 28641
Joined: Sat Sep 10, 2005 11:00 pm
Location: Staffs
Contact:

Fri May 18, 2012 7:25 pm

redcar wrote:
e30-dk wrote:thats never a good thing surely 8O
Why not?
Ask anybody thats mopped up after one....
e30-EVN
Old Skooler
Old Skooler
Posts: 3382
Joined: Sun Dec 13, 2009 11:00 pm
Location: S.Wales

Fri May 18, 2012 7:39 pm

Ask anybody thats mopped up after one....
:lol:
A 2 door e30 with 8 cylinders, what could be better winkeye :D
User avatar
Coyote_ar
E30 Zone Newbie
E30 Zone Newbie
Posts: 108
Joined: Mon Jan 07, 2008 11:00 pm
Location: Argentina

Sun May 27, 2012 9:50 am

emissions and economy is the reason they run it so hot ... not a good deal on the long therm.

i will try to get a 80c thermostat, that should help in summer.
User avatar
johnmaccow
E30 Zone Regular
E30 Zone Regular
Posts: 351
Joined: Mon Aug 23, 2010 11:00 pm
Location: Gateshead

Sun Jun 03, 2012 8:48 pm

So would a reliable 350-400 be possible with a decent mapped smaller turbo conversion? Also how would it compare in cost and reliability against a s50?
Post Reply