| |
BUSY BOLTERS Are you one?  The Shop Area
continues to pull in the most views on the Stovebolt. In August alone there were over 22,000 views in those 13 forums.
| | Click on image for the lowdown. 
====
| | |
2 members (TGP, Joe W),
440
guests, and
1
robot. | | Key: Admin,
Global Mod,
Mod | | | Forums66 Topics126,777 Posts1,039,270 Members48,100 | | Most Online2,175
Jul 21st, 2025 | | 
#75732 03/30/2007 10:02 PM | Joined: Mar 2007 Posts: 11 New Guy | | New Guy Joined: Mar 2007 Posts: 11 | After miraculously locating a head, rods and TRW forged pistons and a Schiefer flywheel (all NOS), and putting the rebuilt 261 into my '50 half ton, I've found myself with a spare set of rods; NOS pistons, rings & head gasket; and the original 1959 261 head.
I've also got a couple of 235 short blocks. I'm thinking of turning one of the 235 short blocks and the 261 spares into a second 261. The 261 piston & rings are std, so the 235 head would need to be bored to 3.75. Is that too much of a stretch from the 3.56 (or more if bored) of a 235?
Is there any other difference between a 235 block and a 261 block, apart from the steam vent holes and full pressure & flow oil tappings? Both these issues can be addressed in the machine shop, so are there any other reasons why this couldn't or shouldn't be done?
What think ye all? Thanks! | | |
#75733 03/31/2007 1:28 AM | Joined: Feb 2004 Posts: 28,674 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 28,674 | You'll hit water long before you get the 235 bored big enough to take the 261 pistons! The only way it might work would be to bore it out big enough to accept 3.75" by .125" wall-thickness sleeves, and turn the 235 into a wet-sleeve engine. We've done that on a few race engines, notably 2.3 liter Ford 4-cylinders with 307 Chevy V-8 pistons, but it's going to be a very short-life engine. Your best bet will be to find another 261 block somewhere.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | |
#75734 03/31/2007 5:11 PM | Joined: Mar 2007 Posts: 11 New Guy | | New Guy Joined: Mar 2007 Posts: 11 | Ouch! That's what I needed to know (but didn't really want to hear). I got the notion from somewhere that 235 and 261 blocks were the same except for those steam vent holes and oil tappings. Not!
Thanks for the feedback - and for saving me a lot of frustration.
Mark | | |
#75735 03/31/2007 5:35 PM | Joined: Jul 2003 Posts: 132 'Bolter | | 'Bolter Joined: Jul 2003 Posts: 132 | I second HRL's advise. Actually tried that years ago. Didn't hit water until after the engine was running. Lot's of steam out the tailpipe! I really didn't need the practice, but I got to pull the engine and move all the new parts over to the 261 block I should have used in the first place. | | |
#75736 04/03/2007 12:53 AM | Joined: Oct 2001 Posts: 3,458 Extreme Gabster | | Extreme Gabster Joined: Oct 2001 Posts: 3,458 | The steam vent holes are there because of the bore differance- the 235 has space inbetween the cylinders for water to circulate. The 261's cylinders meet eachother (siamesed), so there is need for the steam holes to let trapped water or steam flow up through the head.
Paint & Body Shop moderator
A lone amateur built the Ark. A large group of professionals built the Titanic. | | |
|
|
| |
