home register FAQ memberlist calendar

Go Back   Turbobricks Forums > Mechanical > performance & modifications

Reply
 
Thread Tools Display Modes
Old 11-02-2021, 09:43 AM   #1
Truebeliever
Newbie
 
Join Date: Aug 2018
Default First motor build questions(how bad did I screw up)

Hello all,
I’m currently trying to build a b230f block for a goal of 400ish crank hp. I’ve settled on the formula of h beam rods and and stock ft pistons. There is still a lot tbd, but as of now I’ve decided to focus on the short block.
Long story short, I grabbed a wrong shim and gapped one of the second rings to .034 instead of the target .03. Is this wayyyyy to much gap?

In regards to deck height, it seems I’m working with a +.006 based of piston height. I’d probably like to use a oem gasket during break in and me learning my way thru this, with a future option of mls if needed.I guess I’m asking if I should have the block cut down anymore to help with quench/squish.

Last edited by Truebeliever; 11-02-2021 at 02:02 PM.. Reason: Auto correct
Truebeliever is offline   Reply With Quote
Old 11-02-2021, 09:52 AM   #2
JohnMc
PV Abuser
 
JohnMc's Avatar
 
Join Date: May 2004
Location: St. Louis
Default

I wouldn't worry about .034 vs. .03. It's pretty loose, but the old saying is "If your rings are too loose, you'll know it. If they're too tight, everyone will know it."

As for the HG, I forget what the stock HG's compress to, but the MLS comes in a variety of thicknesses. No real need to machine the block to any particular height, just get the MLS that gets you to the next closest size over .033 - .034-ish.
__________________
'63 PV Rat Rod
'93 245 16VT Classic #1141
JohnMc is offline   Reply With Quote
Old 11-02-2021, 10:51 AM   #3
Swedbrick
Board Member
 
Swedbrick's Avatar
 
Join Date: Oct 2016
Location: Netherlands, Source of Grolsch
Default

I messed up in a similar way and ended up with:
top: 0,95 mm
middle: 1,00 mm
oil control: 0,80 mm
PWC max: 0.148 mm (pistons were divided to keep this as little as I could)

Except for a bit of extra pcv to deal with it has been fine since running it in, not even that piston slappy suprisingly
__________________
Volvo 745 - Turbo, LH2.4, M90 swap, IPD springs, 25mm/19mm swaybars, 3.54 \w racingdiff lsd, track/daily
---------------------------------
I sell LH2.4 Chips for Europe!
Swedbrick is online now   Reply With Quote
Old 11-02-2021, 11:31 AM   #4
Stiggy Pop
Board Member
 
Stiggy Pop's Avatar
 
Join Date: Feb 2011
Location: Granville, MA
Default

Quote:
Originally Posted by JohnMc View Post
I wouldn't worry about .034 vs. .03. It's pretty loose, but the old saying is "If your rings are too loose, you'll know it. If they're too tight, everyone will know it."

As for the HG, I forget what the stock HG's compress to, but the MLS comes in a variety of thicknesses. No real need to machine the block to any particular height, just get the MLS that gets you to the next closest size over .033 - .034-ish.
an Elring compressed is 1.2mm or .047". Agreed on using the MLS to dial it. My pistons are .004" up and I just ordered the thickness needed from Cometic to hit my target squish.
__________________
'79 242
943 pickup
Stiggy Pop is offline   Reply With Quote
Old 11-02-2021, 12:41 PM   #5
towerymt
the real Towery
 
towerymt's Avatar
 
Join Date: Sep 2002
Location: VA, USA
Default

I think we did 0.012" above deck for use with the alleged 0.047" HG for 0.035" piston to head clearance. If you want to stick to stock head gaskets like I did, you probably want to take some more off. I'm not the voice of experience here but I think you need to assemble it to measure that 0.006" and not assume/calculate...if that's what you did to reach that figure (I'm not sure, so just saying...)
towerymt is offline   Reply With Quote
Old 11-02-2021, 01:49 PM   #6
Truebeliever
Newbie
 
Join Date: Aug 2018
Default

Ooops

Last edited by Truebeliever; 11-02-2021 at 01:56 PM.. Reason: Better info
Truebeliever is offline   Reply With Quote
Old 11-02-2021, 01:55 PM   #7
Truebeliever
Newbie
 
Join Date: Aug 2018
Default

Quote:
Originally Posted by towerymt View Post
I think we did 0.012" above deck for use with the alleged 0.047" HG for 0.035" piston to head clearance. If you want to stick to stock head gaskets like I did, you probably want to take some more off. I'm not the voice of experience here but I think you need to assemble it to measure that 0.006" and not assume/calculate...if that's what you did to reach that figure (I'm not sure, so just saying...)
I measured it @ .006 on #1 and #3
Truebeliever is offline   Reply With Quote
Old 11-02-2021, 02:28 PM   #8
Stiggy Pop
Board Member
 
Stiggy Pop's Avatar
 
Join Date: Feb 2011
Location: Granville, MA
Default

Quote:
Originally Posted by towerymt View Post
the alleged 0.047" HG
it's not alleged with the Elring, I spoke to their head of engineering about it a few years back.
Stiggy Pop is offline   Reply With Quote
Old 11-02-2021, 05:36 PM   #9
towerymt
the real Towery
 
towerymt's Avatar
 
Join Date: Sep 2002
Location: VA, USA
Default

Quote:
Originally Posted by Stiggy Pop View Post
it's not alleged with the Elring, I spoke to their head of engineering about it a few years back.
Excellent. It used to be a point of contention years ago. Do you know if there was an alternate thickness available for the 96mm redblocks?
towerymt is offline   Reply With Quote
Old 11-02-2021, 06:11 PM   #10
Stiggy Pop
Board Member
 
Stiggy Pop's Avatar
 
Join Date: Feb 2011
Location: Granville, MA
Default

Quote:
Originally Posted by towerymt View Post
Excellent. It used to be a point of contention years ago. Do you know if there was an alternate thickness available for the 96mm redblocks?
yeah that's exactly why I went to get a straight answer, myth confirmed!

I did not ask about alternate thickness because I was planning on running an MLS but it's a great question. I actually got to the head of engineering by cold calling them, so it's worth a few minutes of someone's time if they're interested.
Stiggy Pop is offline   Reply With Quote
Old 11-02-2021, 07:12 PM   #11
redblockpowered
cone dodging dilettante
 
redblockpowered's Avatar
 
Join Date: May 2015
Location: In bed, probably
Default

It's fun the kinds of things you can find out by simply asking.
__________________
1993 944 B230FT/M90 thread here: http://forums.turbobricks.com/showthread.php?t=345277
2x 1991 245 B230F/M47 (LeMons car, street car)
I sell chips for LH 2.4!
redblockpowered is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -4. The time now is 09:43 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.