Engine Rebuild - Advice Wanted

[Guest Boost]

Been measuring and calculating tonight.... Compression ratio or more like how much to skim off the head!

 

The new pistons are 0.1mm shorter than the old ones increasing the deck height to 0.532mm

 

Bore is now 91.8, head gasket is 92.7 x 1.3. Stroke unchanged at 76.95.

 

I calculated the rough shape of cylinder head volume as standard to be 75 x 51.2 x 12.5 to give a volume of 48cc

 

So if I skim 1.5mm off that gives 75 x 51.2 x 11 = 42 cc

 

This gives me a CR of 10.21:1 Paul's spreadsheet also tells me that skimming 1.5mm off will reduce the head volume to 41cc (so my cals were not far off!)

 

This gives a CR of 10.38:1

 

So I think I will skim off 1.5mm or 60 thou in old money and the CR will be somewhere near the 2 figures I've worked out. Happy Days!

[Guest lotusPaul]

I'd still take it off the head and block.

[Guest mower man]

That should be absolutly fine ,my 2.1 ran with zero deck hieght and a 1.5 mill [comperessed gskt] ,can't give chamber figs but asked P,Burgessto modd to give 10.5 cr ,with newman cam stage 2 and single 38 dgas it gave 144 .7 at the crank ,about 127 onthe deck enjoy it!! mick

[Guest lotusPaul]

Not bad with the dgas..shows they work well..

[Guest mower man]

They certainly do !!!!!! mick

[Guest Boost]

Got pistons in now, and even thought the new ones are 0.1mm shorter (from crown to gudgeon pin top) which should have increased the deck height by 0.1mm it has actually reduced it by 0.13mm, must be due to the new main bearings and big end I think. An

 

Any way just re calculated the compression ratio and its now at 10.55:1!.

 

Hope it will hold together!

[Guest Boost]

Few Pics.....

 

 

 

 

 

 

 

 

An error occurred - posting too many pics - Never enough pics!!!

Edited February 9, 2016 by Boost

[Guest Boost]

Strange was not able to post all the pics in one post!

 

Here's the rest

 

 

 

 

 

 

I'll post more as things progress..

[Guest mower man]

Very nice work ,clean and tidy and organised mick

[Bob Tucker]

That could well be the first Pinto not to leak oil everywhere

[Guest mower man]

The only time a pinto don't leak is when its all leaked out

[IanS]

Wrong there are 2 times a pinto does not leak oil.

First is when brand new before the oil goes in, the second MM has correct

[Guest Boost]

Fingers crossed! There was a very generous amount of sealant around the the joints between the cork & rubber gaskets!

[Guest 2b cruising]

If it does not leak after or while it has been working, it could be worth millions.

[Guest lotusPaul]

Pintos do not leak oil..They recycle it back into the ground.