36 replies to this topic

[Echan42]

How did you calculate the 40 thou 2.92cc measurement?
I skimmed a 295 40thou from stock to get 10.1 worh flattops. ( 42 thou actually but hey)

Do you remember your final head chamber volume after 40thou? I'd love to contrast my numbers.

 

I measured using parafin, on a level surface, dropped the valves in after spreading grease in the seats,  added 20cc wax, and measured with my digital caliper.

My original chamber came to 27,6 and 20cc of parafin gave me 105thou.

So roughly

100thou = 7,7cc

40 thou = 2.90cc

 

Is there any better way to determine how much thous take away how many ccs?

I still have to do this on the other chambers since vizzard mentions not all cylinders are identical, if my calculations are correct all I'd need to measure is the deck height once I take my original head off.

Any tips or corrections are very welcome

[Dusky]

How did you calculate the 40 thou 2.92cc measurement?
I skimmed a 295 40thou from stock to get 10.1 worh flattops. ( 42 thou actually but hey)

Do you remember your final head chamber volume after 40thou? I'd love to contrast my numbers.

I measured using parafin, on a level surface, dropped the valves in after spreading grease in the seats, added 20cc wax, and measured with my digital caliper.
My original chamber came to 27,6 and 20cc of parafin gave me 105thou.
So roughly
100thou = 7,7cc
40 thou = 2.90cc

Is there any better way to determine how much thous take away how many ccs?
I still have to do this on the other chambers since vizzard mentions not all cylinders are identical, if my calculations are correct all I'd need to measure is the deck height once I take my original head off.
Any tips or corrections are very welcome

I ended up somwhere around the 24cc mark in the chambers, 23,.. IIRC.
The chambers are wider at the top so you lose CC's a tad quicker there.
Best thing is using flat top pistons with it, prevents from over skimming the head

[Echan42]

Woo! Parts came! I'm so excited!

I was opening packages and sorting parts all day yesterday.

On my way out to the machine show I realized one problem, my vlaves and cotters don't match.

My original intake valves are 1.2" and my exhaust are 1" single groove cotter, but I ordered old type wide cotter.

Lucky enough I found some stick for the old cotter online.

Quick question before I proceed with the build.

Do I search for single groove valves or should I just order the old style large groove cotter, was that design inferior? Also haynes shows that the large cotters where fixed with a clip.

Look ar part 17.

 

Not only is this part mostly ignored in most builds I've seen it's also unavailable and I don't know if the spring top caps would be too high for me to fit it.

 

So I'm faced with a choice, either buy new 1" and 1.2" valves wich I'm finding on minispares, or use the old 2a11 without the top clip.

What would you guys do?

Edited by Echan42, 17 October 2019 - 02:56 PM.

[Turbo Phil]

You don’t need to use the clips, as you’ve noticed most people don’t.
But you need to use the correct top caps to match the collets and the collets obviously have to match the valves.
I’m a little confused to what you actually have at the moment ?

Phil.

Edited by Turbo Phil, 17 October 2019 - 06:43 PM.

[Echan42]

I’m a little confused to what you actually have at the moment ?

Phil.

I have:

Single groove collets

Wide groove old style valves

Top caps that came out the 12g295, that used single groove collets

 

The top caps fit single grooves really flush and I suspect they would fit the 2A11-S collets, but yeah, I've no way to try that.

What you say makes me think new 1" and 1.2" valves are the way to go, but I'm only finding larger ones in minispares

 

EDIT:
I just got an email back from an Australian store where I found the old style cotters.

"Caps are the same  for  the single smalll and large cotters."

So that's that out of the way, hope they come soon!

 

Edited by Echan42, 20 October 2019 - 10:37 PM.

[Echan42]

Just waiting for the last package that's arriving in 10 days, I bought the wrong springs, for the time being here's the paintjob I gave the valve rocker and head.

The letters say "memento mori" wich I chose because it sounds like "remember morris" and also is sorta a reference to the fact the engine is old and most cars that old are either scrapped or broken down.

Edited by Echan42, 19 November 2019 - 11:48 AM.

[Echan42]

Quick update, put everything together, time to check clearances and put everything back in.

thanks for your help guys. rebuild