Mopar 273-4bbl Combo

Charlie A · 11-23-2016, 11:59 AM

Quote:

Originally Posted by Rob Ayres

PM sent. Call me

You should call Rob.

James L Miller · 11-23-2016, 01:20 PM

I've known Rob for many years. He drove my old Joe Ralph Thompson AWB Plymouth when a mutual friend had it. I bought that car from Fred and I had posted photos of it and Rob saw it. He described it as a scary car with the straight front axle and regular gear box. I've never actually met Rob in person, but have exchanged e-mails for about 15 years. I had that article in a Hot Rod magazine when I was a kid. I guess the Mopar world is small enough where you get to know the other Mopar guys. Rob has a mid-1960s Impala that he's running with his son.

larrylomascolo · 11-23-2016, 02:32 PM

I had a friend who,s dad owned a 68 dodge dart,273 4spd,hub caps,14 inch bias ply green with black vinyl roof,we would take it out after his dad went to sleep,pushing it down the road,We raced a few guys with the dart and that little screamer being bone stock was impressive,good combo but like Paul said get your wallet out

James L Miller · 11-25-2016, 02:18 PM

Boy, everyone is telling me to get the wallet out. I think I have $40 in there or maybe a bit more. It looks like the rods and pistons might be some of the big ticket items. It looks like Melling has some 1/8" wall sleeves that would reduce a 318 stock bore (Ø3.91") down to the 273 range (Ø3.66" or so). I'm thinking using Hardblok in the wimpy 273 blocks will be a cheaper way to go. The Hardblok is about $100, sleeves are around $20-40 each, plus machining. I'll see what my machinist/engine builder wants to do, but the Hardblok looks like a less expensive way to beef up the thin cylinder walls. I wonder if the later 273 blocks had thicker cylinder walls?

Paul Wong · 11-25-2016, 03:06 PM

delete

Terry Bride · 11-25-2016, 03:19 PM

I'm slowly working on this same combination for a 66 Barracuda.

You need to keep in mind that the sleeve will need a step to retain it in the parent bore. You can't stick a 3.910" O.D. sleeve into a 3.910" bore. There will be nothing to support the sleeve. You will need a sleeve with enough oversize beyond the parent bore dia. to allow an adequate step to register against. I have not found any straight sleeve with enough wall thickness to do this. In this case, the only way to do the sleeving correctly is to get a set of flanged liners and counter bore the deck for the flange.

A custom sleeve will be an expensive investment along with some fairly substantial machining costs but in the end, you will have a block that will maintain it's bore size for many re-hones.

I will have to sonic test the 1967 273 block I have to see what it has for thickness.
In the mean time, I am saving up to purchase the pistons and maybe sleeves.

James L Miller · 11-25-2016, 06:53 PM

I did catch my engine builder while he was taking a break at the beach on the east coast of Florida. He was thinking along your lines but using a 340 block and get custom sleeves with the flange as you mentioned. That would be really stout cylinder walls for a 273 size engine. He said he did that many years ago when he ran his Colt in MP with a 280 CID (3.935" bore, probably the old 2.96" stroke crank) with W2 heads. I wasn't sure how big of a step was needed at the bottom near the main webbings.

I think I will start with a 273 block with Hardblok on the first go. I don't want to spend a ton of money on this project. The idea is to run quick enough to qualify in Div. 4 divisional and national events here (don't plan on going to Indy).

Frank Castros · 11-27-2016, 09:42 AM

James,

I also love the combination and wish you well with your build.

Sleeving a 340 X block would be the ultimate, but very expensive (if you can find one) Hardblock in a 273 is the way to go on a budget.

Also speak to Dean Oliver about a carburetor.

No disrespect to all who have offered their advice but Paul Wong is the guy I would consult.

11-23-2016, 01:20 PM	#2
James L Miller Member Join Date: Apr 2005 Posts: 494 Likes: 6 Liked 25 Times in 16 Posts	Re: Mopar 273-4bbl Combo I've known Rob for many years. He drove my old Joe Ralph Thompson AWB Plymouth when a mutual friend had it. I bought that car from Fred and I had posted photos of it and Rob saw it. He described it as a scary car with the straight front axle and regular gear box. I've never actually met Rob in person, but have exchanged e-mails for about 15 years. I had that article in a Hot Rod magazine when I was a kid. I guess the Mopar world is small enough where you get to know the other Mopar guys. Rob has a mid-1960s Impala that he's running with his son. __________________ Mopar 2 Ya!

11-23-2016, 02:32 PM	#3
larrylomascolo Member Join Date: Nov 2008 Location: Ontario,canada Posts: 440 Likes: 70 Liked 66 Times in 29 Posts	Re: Mopar 273-4bbl Combo I had a friend who,s dad owned a 68 dodge dart,273 4spd,hub caps,14 inch bias ply green with black vinyl roof,we would take it out after his dad went to sleep,pushing it down the road,We raced a few guys with the dart and that little screamer being bone stock was impressive,good combo but like Paul said get your wallet out

11-25-2016, 02:18 PM	#4
James L Miller Member Join Date: Apr 2005 Posts: 494 Likes: 6 Liked 25 Times in 16 Posts	Re: Mopar 273-4bbl Combo Boy, everyone is telling me to get the wallet out. I think I have $40 in there or maybe a bit more. It looks like the rods and pistons might be some of the big ticket items. It looks like Melling has some 1/8" wall sleeves that would reduce a 318 stock bore (Ø3.91") down to the 273 range (Ø3.66" or so). I'm thinking using Hardblok in the wimpy 273 blocks will be a cheaper way to go. The Hardblok is about $100, sleeves are around $20-40 each, plus machining. I'll see what my machinist/engine builder wants to do, but the Hardblok looks like a less expensive way to beef up the thin cylinder walls. I wonder if the later 273 blocks had thicker cylinder walls? __________________ Mopar 2 Ya!

11-25-2016, 03:06 PM	#5
Paul Wong Member Join Date: Jan 2003 Location: Las Vegas Posts: 384 Likes: 101 Liked 419 Times in 85 Posts	Re: Mopar 273-4bbl Combo delete Last edited by Paul Wong; 12-01-2016 at 02:10 PM. Reason: delete

11-25-2016, 03:19 PM	#6
Terry Bride Junior Member Join Date: Jun 2011 Posts: 23 Likes: 8 Liked 0 Times in 0 Posts	Re: Mopar 273-4bbl Combo I'm slowly working on this same combination for a 66 Barracuda. You need to keep in mind that the sleeve will need a step to retain it in the parent bore. You can't stick a 3.910" O.D. sleeve into a 3.910" bore. There will be nothing to support the sleeve. You will need a sleeve with enough oversize beyond the parent bore dia. to allow an adequate step to register against. I have not found any straight sleeve with enough wall thickness to do this. In this case, the only way to do the sleeving correctly is to get a set of flanged liners and counter bore the deck for the flange. A custom sleeve will be an expensive investment along with some fairly substantial machining costs but in the end, you will have a block that will maintain it's bore size for many re-hones. I will have to sonic test the 1967 273 block I have to see what it has for thickness. In the mean time, I am saving up to purchase the pistons and maybe sleeves. Last edited by Terry Bride; 11-25-2016 at 03:21 PM.

11-25-2016, 06:53 PM	#7
James L Miller Member Join Date: Apr 2005 Posts: 494 Likes: 6 Liked 25 Times in 16 Posts	Re: Mopar 273-4bbl Combo I did catch my engine builder while he was taking a break at the beach on the east coast of Florida. He was thinking along your lines but using a 340 block and get custom sleeves with the flange as you mentioned. That would be really stout cylinder walls for a 273 size engine. He said he did that many years ago when he ran his Colt in MP with a 280 CID (3.935" bore, probably the old 2.96" stroke crank) with W2 heads. I wasn't sure how big of a step was needed at the bottom near the main webbings. I think I will start with a 273 block with Hardblok on the first go. I don't want to spend a ton of money on this project. The idea is to run quick enough to qualify in Div. 4 divisional and national events here (don't plan on going to Indy). __________________ Mopar 2 Ya!

11-27-2016, 09:42 AM	#8
Frank Castros VIP Member Join Date: Nov 2001 Location: The Lowcountry. Posts: 2,964 Likes: 2,571 Liked 2,715 Times in 956 Posts	Re: Mopar 273-4bbl Combo James, I also love the combination and wish you well with your build. Sleeving a 340 X block would be the ultimate, but very expensive (if you can find one) Hardblock in a 273 is the way to go on a budget. Also speak to Dean Oliver about a carburetor. No disrespect to all who have offered their advice but Paul Wong is the guy I would consult.