Ausmini
It is currently Thu Jun 26, 2025 8:20 pm

Board index » Mini Chat » Mini & A/A+ Series Mods

All times are UTC + 10 hours




Post new topic Reply to topic  Page 1 of 2
  [ 16 posts ]  Go to page 1, 2  Next
  Print view Previous topic | Next topic 
Author Message
Kennomini
 Post subject: over size bore question
PostPosted: Mon Sep 10, 2012 6:29 pm 
Offline
1275cc
1275cc
User avatar

Joined: Thu May 24, 2007 7:19 pm
Posts: 5370
Location: Yandina,Sunshine Coast,QLD
What over sized pistons are available for a 1098?
And (fore example) is 0.100 thou measured in diameter or radius?

_________________
Respect mine and I'll respect yours.
Top
 Profile  
 
Nicho
 Post subject:
PostPosted: Mon Sep 10, 2012 7:13 pm 
Offline
848cc
848cc
User avatar

Joined: Tue Jul 31, 2012 8:20 pm
Posts: 305
Location: Maryknoll
100 thou in graham russel flat tops I think is as high as you go maybe 120 but others will tell you. In Hypertec you'll only go 60 to 80 thou in dished. Check all the parts sites what they show is what you can do
http://www.minis.com.au/
Talk to Lindsay he'll set you straight.

_________________
If its got tits or wheels its gonna cost you

1973 Solid side Leyland Mini Panelvan 1100 in Hairy Lime(Elma)
1976 Clubby project in progress
1966 Morris Mini Deluxe in need of a full resto
1971 Mini K Garden Art
Top
 Profile  
 
mini_mad_matt
 Post subject:
PostPosted: Mon Sep 10, 2012 9:03 pm 
Offline
1098cc
1098cc
User avatar

Joined: Tue Aug 05, 2008 8:03 pm
Posts: 1479
Location: Qld, Brisbane
the oversize of the piston is diameter
Top
 Profile  
 
drmini in aust
 Post subject:
PostPosted: Thu Sep 20, 2012 8:33 pm 
Offline
religious status
religious status
User avatar

Joined: Fri Mar 19, 2004 6:19 pm
Posts: 39752
Location: near Baulkham Hills, NSW
I built 3x 1098s years ago with 68mm Hillman Imp pistons.
These are pretty much NLA now except from JP pistons in Adelaide.
Matt Read `TheMiniMan' built a few this size too, I think he used Suzuki bike pistons- not sure which ones.

68mm offset bores in a 1098 = 1220cc approx.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R. :mrgreen:
Top
 Profile  
 
GT mowog
 Post subject:
PostPosted: Fri Sep 21, 2012 1:37 pm 
Offline
Mods rock!
User avatar

Joined: Fri Oct 03, 2008 9:02 pm
Posts: 5079
drmini in aust wrote:
I built 3x 1098s years ago with 68mm Hillman Imp pistons.
These are pretty much NLA now except from JP pistons in Adelaide.
Matt Read `TheMiniMan' built a few this size too, I think he used Suzuki bike pistons- not sure which ones.

68mm offset bores in a 1098 = 1220cc approx.

_________________
Image
Top
 Profile  
 
Morris 1100
 Post subject:
PostPosted: Fri Sep 21, 2012 5:21 pm 
Offline
Causing or creating vexation

Joined: Wed Jul 21, 2004 10:32 pm
Posts: 19124
When you can only find one piston that will suit the particular job it very easy to find the best ones. :lol:
Top
 Profile  
 
850man
 Post subject:
PostPosted: Fri Sep 21, 2012 6:18 pm 
Offline
1098cc
1098cc

Joined: Tue Jun 12, 2007 2:07 pm
Posts: 1882
Location: Lemmings, everywhere.
I feel a case of Déjà vu. :roll:

_________________
Have a Nice Day.
If already having a nice day please disregard.
Top
 Profile  
 
Morris 1100
 Post subject:
PostPosted: Fri Sep 21, 2012 6:23 pm 
Offline
Causing or creating vexation

Joined: Wed Jul 21, 2004 10:32 pm
Posts: 19124
850man wrote:
I wont be going back there, too many lemmings.


I feel a case of Déjà vu. :lol: :lol: :lol:
Top
 Profile  
 
TheMiniMan
 Post subject:
PostPosted: Fri Sep 21, 2012 7:16 pm 
Offline
Bimmer Twinky
User avatar

Joined: Mon Sep 06, 2004 4:36 pm
Posts: 8606
Location: Brisbane
drmini in aust wrote:
I built 3x 1098s years ago with 68mm Hillman Imp pistons.
These are pretty much NLA now except from JP pistons in Adelaide.
Matt Read `TheMiniMan' built a few this size too, I think he used Suzuki bike pistons- not sure which ones.

68mm offset bores in a 1098 = 1220cc approx.


we did a pile of imp piston donks way back,,,, i still have one here ashley

& yeah we did make a few small-bore donks with motorbike pistons in em,,, i think they were GS750 from my terrible mamory glands,,, bush the rod to suit the gudgeon & away you go,,, did them so long ago i don`t know who got em now :-(

stoopid heart medication makes me forget what,,, ar,,, er,,, what were we talking about again???

:-)

_________________
No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.
Top
 Profile  
 
68Rusty
 Post subject:
PostPosted: Fri Sep 21, 2012 7:50 pm 
Offline
998cc
998cc
User avatar

Joined: Thu Jun 17, 2010 8:55 pm
Posts: 723
Location: Central West
Warwick is currently building my imp piston motor; I picked original factory imp pistons up off ebay with original rings.

Will get the verdict from Warwick soon and hope all has gone well and I can pick it up asap :D

Also getting whole thing balance and putting 940 1100s head on it with 40mm Dellorto.

_________________
1968 Morris Mini Deluxe - members gallery
1970 Morris Cooper S - members gallery
Mini's I grew up with
Slot car couch
Top
 Profile  
 
drmini in aust
 Post subject:
PostPosted: Sun Sep 23, 2012 3:27 pm 
Offline
religious status
religious status
User avatar

Joined: Fri Mar 19, 2004 6:19 pm
Posts: 39752
Location: near Baulkham Hills, NSW
68Rusty wrote:
Warwick is currently building my imp piston motor; I picked original factory imp pistons up off ebay with original rings.

Will get the verdict from Warwick soon and hope all has gone well and I can pick it up asap :D

Also getting whole thing balance and putting 940 1100s head on it with 40mm Dellorto.

It should go good, mine certainly did back in 1967. Did low 16s at Castlereagh Dragway on 145/10 road rubber.
When a circlip came out and the gudgeon pin scored the bore I stuck all the good bits (twin HS4s, ported head, 544 cam) into a new Morris 1100S short motor, but it just wasn't the same.. Whirly bits all too heavy. :cry:

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R. :mrgreen:
Top
 Profile  
 
68Rusty
 Post subject:
PostPosted: Sun Sep 23, 2012 5:57 pm 
Offline
998cc
998cc
User avatar

Joined: Thu Jun 17, 2010 8:55 pm
Posts: 723
Location: Central West
drmini in aust wrote:
68Rusty wrote:
Warwick is currently building my imp piston motor; I picked original factory imp pistons up off ebay with original rings.

Will get the verdict from Warwick soon and hope all has gone well and I can pick it up asap :D

Also getting whole thing balance and putting 940 1100s head on it with 40mm Dellorto.

It should go good, mine certainly did back in 1967. Did low 16s at Castlereagh Dragway on 145/10 road rubber.
When a circlip came out and the gudgeon pin scored the bore I stuck all the good bits (twin HS4s, ported head, 544 cam) into a new Morris 1100S short motor, but it just wasn't the same.. Whirly bits all too heavy. :cry:


Low 16's is great! I was only getting mid 15's out of my XU1 in the mid 90's before it was stollen.

I hope it will be a nice little road motor. I have also added a 3.44 ratio diff so will be nicer cruising.

_________________
1968 Morris Mini Deluxe - members gallery
1970 Morris Cooper S - members gallery
Mini's I grew up with
Slot car couch
Top
 Profile  
 
5portsrock
 Post subject: gaskets
PostPosted: Tue Nov 13, 2012 6:12 pm 
Offline
848cc
848cc

Joined: Wed Dec 10, 2008 10:36 pm
Posts: 11
Location: hampshire ,uk
Hi, im contemplating going to an imp piston on my 998.
How did you all get on as regards the head gasket ?
The bore hole seem considerably smaller than the 68mm piston diameter ? Thanks alot
Top
 Profile  
 
drmini in aust
 Post subject: Re: gaskets
PostPosted: Tue Nov 13, 2012 6:30 pm 
Offline
religious status
religious status
User avatar

Joined: Fri Mar 19, 2004 6:19 pm
Posts: 39752
Location: near Baulkham Hills, NSW
5portsrock wrote:
Hi, im contemplating going to an imp piston on my 998.
How did you all get on as regards the head gasket ?
The bore hole seem considerably smaller than the 68mm piston diameter ? Thanks alot

I notched the block to clear the exhaust valve lift, and used a 12G940 (Morris 1100S) head, and 1275 gasket.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R. :mrgreen:
Top
 Profile  
 
Boostedmini
 Post subject:
PostPosted: Wed Nov 14, 2012 6:30 am 
Offline
998cc
998cc
User avatar

Joined: Thu Sep 23, 2004 2:24 pm
Posts: 1170
Location: Quakers Hill - Only the Hills
I have a 1220 Imp piston motor too, it has a 648 cam and 12G940 head, it went like a rocket and sounded sweet.
started to blow smoke when a ring broke, been sitting under the bench ever since.

great little engine

Grant

_________________
Image

100% Pure A Series Turbo
Morris - The Original RedBull Racing
Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  Page 1 of 2
  [ 16 posts ]  Go to page 1, 2  Next

Board index » Mini Chat » Mini & A/A+ Series Mods

All times are UTC + 10 hours


Who is online

Users browsing this forum: No registered users and 23 guests

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  

© 2016 Ausmini. All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.