logo
12 Port News - Features
12 Port History
Casting Numbers
Online Store
Tech Tips
Become a Member
Previous Thread
Next Thread
Print Thread
Rate Thread
#90270 07/13/16 09:09 PM
Joined: Jul 2016
Posts: 21
J
Jmay Offline OP
Active BB Member
OP Offline
Active BB Member
J
Joined: Jul 2016
Posts: 21
Picked up another 6 today the owner didn't know what it was. The block casting #s say it can be either 230 or 250. So I got these of the distributor pad f1024ta. Anyone know what that means?

Jmay #90273 07/14/16 06:43 PM
Joined: Sep 2008
Posts: 3,673
Likes: 42
1000 Post Club
****
Offline
1000 Post Club
****
Joined: Sep 2008
Posts: 3,673
Likes: 42
The fastest way to tell the difference between the 230's and 250's is to look inside one of the spark plug holes at the piston tops. 230's will have a flat top and 250's will have a dished piston. Those #'s on the distributor pad may or may not point you in the right direction, but in just a few minutes, the piston will give you a better clue.



Class III CNC Machinist/Programmer
Joined: Dec 2014
Posts: 335
Contributor
Offline
Contributor
Joined: Dec 2014
Posts: 335
Originally Posted By: CNC-Dude #5585
The fastest way to tell the difference between the 230's and 250's is to look inside one of the spark plug holes at the piston tops. 230's will have a flat top and 250's will have a dished piston. Those #'s on the distributor pad may or may not point you in the right direction, but in just a few minutes, the piston will give you a better clue.


Better yet, overhaul the engine, guess that it's a 250 and buy new pistons. Ignore that the pistons don't reach the deck, put it together anyways and see if it runs like crap and has awful compression. If it does, then you'll know it's a 230. Not as fast as looking at the top of the pistons, though. :-)


Mark
'67 Camaro L6-250
mshaw230 #90277 07/15/16 11:16 AM
Joined: Jul 2016
Posts: 21
J
Jmay Offline OP
Active BB Member
OP Offline
Active BB Member
J
Joined: Jul 2016
Posts: 21
Originally Posted By: mshaw230
Originally Posted By: CNC-Dude #5585
The fastest way to tell the difference between the 230's and 250's is to look inside one of the spark plug holes at the piston tops. 230's will have a flat top and 250's will have a dished piston. Those #'s on the distributor pad may or may not point you in the right direction, but in just a few minutes, the piston will give you a better clue.


Better yet, overhaul the engine, guess that it's a 250 and buy new pistons. Ignore that the pistons don't reach the deck, put it together anyways and see if it runs like crap and has awful compression. If it does, then you'll know it's a 230. Not as fast as looking at the top of the pistons, though. :-)


Think I will pass on that method! Is that how you found out? Lol!

Jmay #90281 07/15/16 09:42 PM
Joined: Oct 2007
Posts: 5,045
Likes: 51
1000 Post Club
****
Offline
1000 Post Club
****
Joined: Oct 2007
Posts: 5,045
Likes: 51
It's not a problem. If you get a big enough blower you can still stuff the cylinders full. cool Remove all doubt and buy a 250 crank for the build. smile

Last edited by Beater of the Pack; 07/15/16 09:44 PM.

"I wonder if God created man because he was disappointed in the monkey?" Mark Twain
Jmay #90282 07/16/16 01:26 AM
Joined: Jan 2015
Posts: 376
T
Contributor
Offline
Contributor
T
Joined: Jan 2015
Posts: 376
A 230 with 250 pistons would be a neat twin turbo engine. laugh


1966 C10 292/tko600 http://67-72chevytrucks.com/vboard/showthread.php?t=596643
1964 C20 292/sm420
Jmay #90283 07/16/16 02:35 PM
Joined: Sep 2004
Posts: 5,840
Likes: 1
M
1000 Post Club
***
Offline
1000 Post Club
***
M
Joined: Sep 2004
Posts: 5,840
Likes: 1
It would not be so neat. It would not have any guench.

Last edited by Mean buzzen half dozen A.K.A. Hank; 07/16/16 02:36 PM.

12 port SDS EFI
Jmay #90285 07/16/16 07:12 PM
Joined: Jul 2014
Posts: 10
Likes: 1
O
Active BB Member
Offline
Active BB Member
O
Joined: Jul 2014
Posts: 10
Likes: 1
U PUT A 250 PISTON IN A 230-*WILL STICK UP .104 IN OUT OF BLOCK

Jmay #90287 07/16/16 08:27 PM
Joined: Jul 2014
Posts: 10
Likes: 1
O
Active BB Member
Offline
Active BB Member
O
Joined: Jul 2014
Posts: 10
Likes: 1

Jmay #90298 07/18/16 01:15 AM
Joined: Dec 2014
Posts: 335
Contributor
Offline
Contributor
Joined: Dec 2014
Posts: 335
Well, I didn't do this personally, but it's what I discovered. But hey, it got me to convert to a 250, bump up the compression, port the head and increase intake size, and put in a bigger CAM. It's a whole lot more engine now than it used to be. In the picture you can see how low the carbon rings are.

Anybody need a leftover 250 short block? Well, it comes with a 230 crankshaft.



Mark
'67 Camaro L6-250
mshaw230 #90302 07/18/16 02:31 PM
Joined: Jul 2016
Posts: 21
J
Jmay Offline OP
Active BB Member
OP Offline
Active BB Member
J
Joined: Jul 2016
Posts: 21
Yikes 3:1 compression!

mshaw230 #90305 07/18/16 09:04 PM
Joined: Sep 2004
Posts: 5,840
Likes: 1
M
1000 Post Club
***
Offline
1000 Post Club
***
M
Joined: Sep 2004
Posts: 5,840
Likes: 1
Originally Posted By: mshaw230
Well, I didn't do this personally, but it's what I discovered. But hey, it got me to convert to a 250, bump up the compression, port the head and increase intake size, and put in a bigger CAM. It's a whole lot more engine now than it used to be. In the picture you can see how low the carbon rings are.

Anybody need a leftover 250 short block? Well, it comes with a 230 crankshaft.


I conquer. That is why I stated they 250 Pistons with a 230 crank will not have any quench. Meaning the Pistons will be down the hole at TDC


12 port SDS EFI
Joined: Jan 2015
Posts: 376
T
Contributor
Offline
Contributor
T
Joined: Jan 2015
Posts: 376
Originally Posted By: Mean buzzen half dozen A.K.A. Hank
It would not be so neat. It would not have any guench.


I know, I was joking. lol Hence the big smilie face.


1966 C10 292/tko600 http://67-72chevytrucks.com/vboard/showthread.php?t=596643
1964 C20 292/sm420
Jmay #90309 07/19/16 02:34 AM
Joined: Sep 2004
Posts: 5,840
Likes: 1
M
1000 Post Club
***
Offline
1000 Post Club
***
M
Joined: Sep 2004
Posts: 5,840
Likes: 1
That was not directed to you, the other guy states a 250 piston with a 230 crank will come out above the deck in a few posts.


12 port SDS EFI
Jmay #90350 07/24/16 05:23 PM
Joined: Jul 2014
Posts: 10
Likes: 1
O
Active BB Member
Offline
Active BB Member
O
Joined: Jul 2014
Posts: 10
Likes: 1
DUDE

WRONG AGAIN------THATS WHERE THE TOP RING STOPS--NOT PISTON TOP

BRING PISTON TO TDC -PUT STRAIGHT EDGE ACROSS --USE FEELER GAUGE

Jmay #90351 07/24/16 05:43 PM
Joined: Jul 2014
Posts: 10
Likes: 1
O
Active BB Member
Offline
Active BB Member
O
Joined: Jul 2014
Posts: 10
Likes: 1

Jmay #90353 07/24/16 11:19 PM
Joined: Dec 2014
Posts: 335
Contributor
Offline
Contributor
Joined: Dec 2014
Posts: 335
Not to belabor the point, but I will. Piston #1 is at TDC in the picture. I just got lucky with that photo because I was checking out whether or not the cam was installed a notch or two off and left it at TDC. CAM was fine. We measured at TDC with a feeler gauge just under 0.025", maybe more like 0.0237 or something like that. The stock piston sits below the deck a tad.

I'm sure somebody could do the math, but I use it for entertainment purpose, as I intended in this posting. It makes for a good ice breaker too when you meet another car guy. "You wouldn't believe what this mechanic did to the car. blah blah blah". We all love to commiserate about awful machine shop experiences. Just like ghost stories around a campfire. :-)

My engine is now built nicely, able to deliver well above the 130HP or 140HP that was original. How sweet it is.

Mark


Mark
'67 Camaro L6-250

Moderated by  stock49, Twisted6, will6er 

Link Copied to Clipboard
Who's Online Now
0 members (), 33 guests, and 343 robots.
Key: Admin, Global Mod, Mod
Newest Members
Hollander1967, Hairyclive, THarper, crash, ocean1907
6,817 Registered Users
Sponsored Advertisement
Sponsored Advertisement
This Space is Available
Powered by UBB.threads™ PHP Forum Software 7.7.5