1970 Dodge 383 overbore

Kirk Morgan · 09-10-2020, 08:23 PM

Iam going to rebuild the original 383 in my 70 Challenger. The current bore is 30 over. What is the max bore of this engine? It will be for street use only.
Thanks Kirk

BillK · 09-10-2020, 09:10 PM

Kirk,
For basically stock engines my rule of thumb is to go by the piston sizes that are readily available. If they make a 60 over piston it should be safe to go that size. If you want to go larger with custom pistons you need to sonic check the block and then make a decision.

Paul Precht · 09-10-2020, 09:58 PM

You can also use a standard bore 72 and later style 440 piston which will be .070" over, it has the same CH as the 68-69 383s. I did lots of them when I had my first shop, never a problem.

GTX JOHN · 09-10-2020, 11:20 PM

Quote:

Originally Posted by BillK

Kirk,
For basically stock engines my rule of thumb is to go by the piston sizes that are readily available. If they make a 60 over piston it should be safe to go that size. If you want to go larger with custom pistons you need to sonic check the block and then make a decision.

I have a New in the Box .060 TRW Forged 2293 Pistons I would sell
for $250.00 plus the ride.

BillK · 09-11-2020, 09:17 AM

Quote:

Originally Posted by GTX JOHN

I have a New in the Box .060 TRW Forged 2293 Pistons I would sell
for $250.00 plus the ride.

John,
I will let you know. I have one customer with a bunch of old Mopar stuff and he seems to love the old school parts. He might very well be interested

09-10-2020, 08:23 PM	#1
Kirk Morgan Member Join Date: Jan 2009 Posts: 230 Likes: 1 Liked 80 Times in 44 Posts	1970 Dodge 383 overbore Iam going to rebuild the original 383 in my 70 Challenger. The current bore is 30 over. What is the max bore of this engine? It will be for street use only. Thanks Kirk

09-10-2020, 09:10 PM	#2
BillK Member Join Date: Nov 2005 Location: Waldorf Md Posts: 230 Likes: 12 Liked 30 Times in 17 Posts	Re: 1970 Dodge 383 overbore Kirk, For basically stock engines my rule of thumb is to go by the piston sizes that are readily available. If they make a 60 over piston it should be safe to go that size. If you want to go larger with custom pistons you need to sonic check the block and then make a decision. __________________ Bill Koustenis

09-10-2020, 09:58 PM	#3
Paul Precht Senior Member Join Date: Dec 2001 Location: Elysburg, Pa Posts: 733 Likes: 360 Liked 327 Times in 121 Posts	Re: 1970 Dodge 383 overbore You can also use a standard bore 72 and later style 440 piston which will be .070" over, it has the same CH as the 68-69 383s. I did lots of them when I had my first shop, never a problem.