Engine Performance This section is for discussion on all engine building related questions.
Sponsored by:
Sponsored by: KPower

85.5mm Cometic .030" on an 84mm bore??

Thread Tools
 
Search this Thread
 
Old 02-07-2016, 05:04 PM
  #1  
Elite Member
Thread Starter
iTrader: (14)
 
GeneSplicer's Avatar
 
Join Date: Sep 2009
Location: Birmingham, AL
Posts: 2,101
Total Cats: 180
Default 85.5mm Cometic .030" on an 84mm bore??

I see mixed things about using an oversize hg on builds... question is, what's too big?
Not sure how/why i ended up with a 85.5mm bore Cometic for my 84mm bored block.
What neg effects would i see on this turboed block if i use it? Pass or fail?
GeneSplicer is offline  
Old 02-07-2016, 05:17 PM
  #2  
SADFab Destructive Testing Engineer
iTrader: (5)
 
aidandj's Avatar
 
Join Date: Apr 2014
Location: Beaverton, USA
Posts: 18,642
Total Cats: 1,866
Default

The only answer is to bore your block to 85.5
aidandj is offline  
Old 02-07-2016, 05:48 PM
  #3  
Elite Member
Thread Starter
iTrader: (14)
 
GeneSplicer's Avatar
 
Join Date: Sep 2009
Location: Birmingham, AL
Posts: 2,101
Total Cats: 180
Default

Oh man... well, got all disassembled and headed back to machine shop... guess that means i need to buy another set of pistons too. Anyone need some 84mm supertechs?

I'll do this if i get my 2 gps units in the mail tomorrow

I *could* get the right gasket - but dont really feel like shelling out another $120ish - ya know?
GeneSplicer is offline  
Old 02-07-2016, 05:50 PM
  #4  
SADFab Destructive Testing Engineer
iTrader: (5)
 
aidandj's Avatar
 
Join Date: Apr 2014
Location: Beaverton, USA
Posts: 18,642
Total Cats: 1,866
Default

If the 84mm pistons get sent to me then your gps units can be in overnight mail tomorrow at 8am.

aidandj is offline  
Old 02-07-2016, 06:22 PM
  #5  
Elite Member
Thread Starter
iTrader: (14)
 
GeneSplicer's Avatar
 
Join Date: Sep 2009
Location: Birmingham, AL
Posts: 2,101
Total Cats: 180
Default

Originally Posted by aidandj
If the 84mm pistons get sent to me then your gps units can be in overnight mail tomorrow at 8am.

lol
GeneSplicer is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
xcoldricex
Cars for sale/trade
5
03-13-2016 07:05 PM
Silentoreo34
Miata parts for sale/trade
12
02-27-2016 01:23 PM
Andy@24
DIY Turbo Discussion
7
02-09-2016 08:00 PM
fe3tmx5?
Miata parts for sale/trade
0
02-07-2016 01:39 PM
FAB
Fab9 Tuning - Miata Performance Parts
0
02-05-2016 02:38 PM



Quick Reply: 85.5mm Cometic .030" on an 84mm bore??



All times are GMT -4. The time now is 07:13 PM.