225 /6's created equal?

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Small Block

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Were they all created equal whether in a 4 door or a demon or a cuda or what ever. Did they all come with the same goodies inside? Compression the same in all 225's? I know there were the super six's with different carbs and intakes. Give me some feedback please. What variables were there in/on the 225? Thanks
Small Block
 
All 225s compression was the same. I think the only difference was some had forgue or cast crankshafts. :read2:
 
Crank register diameter changed in 1968. Hardened valve seats in 1972. Electronic ignition in 1973. Lost the drool tubes in 1975 (peanut head). Cast crank (big end of rods were narrowed also) and air injection in 1976 or '77. Hydraulic lifters in 1981. The only vehicle specific differences I am aware of was in the slants used in 1 ton trucks. :shock: The blocks were selected for minimal core shift, they had valve rotators, and the cranks were nitrided.
 
Bill
Grumps has it pegged. As for builds BH blocks are considered the best by some. Heads- 68-74 is my favorite era. My take on blocks-Just look for minimal core shift and build it. Cranks- look for one that doesnt have deep holes in the counter weights. Cast crank engines are lighter 76-80. I dont have enough experience on the Hydro 81-up to make a call.
My 05.
Frank
 
There were also a number of cam changes over the years, as well as distributor recurving. Other than possibly a different distributor curve and carb jetting, there wasn't much difference in parts between different models within a year.
 
There were several different carbs too. There are two different Holley 1920's. The Holley 1945 1 bbl, and the Carter BBS.
The two barrel Carter BBD was offered in the Super Six option.
There was a 1 bbl offered for the Feather Duster and Dodge Dart Lite that had some interesting calibrations to get the mileage up in 1976.
The Hyperpak option used a small Carter AFB. This was pretty much the only option that included a dual iron exhaust manifold sytem.
Overseas there were a bunch of different offerings for options. Some of them multiple carbs. That's all fuzzy. Look into South American, Australian and South African slant sixes.
There's a guy in South Africa tooling up to offer repops of the four barrel, and dual two barrel intakes.
Australia has several aftermarket offerings, but I don't know if they were offered as options for production.

CJ
 
See? That's what I get for not fully reading the original post! :eek:ops:

Across different years, there were some combustion chamber improvements.

The head was designed around the 170. It was not redesigned or substantially changed to work well with the larger 198 and 225.

Sorry for being a goober and posting junk about carbs and intakes and stuff.

CJ
 
Even with all the changes throughout the years, I still base my choice for blocks to build by which one is closest to the garage door so it's easiest to load on the truck.

Heads are a different story. I only use peanut plug heads. I give the drool tube heads away for cores. It has nothing to do with chamber design, I just hate drool tubes.
 
Slantzilla...Why do you hate drool tubes ? .. Im new to the slant 6 world and I just want to know all that I can about them. :-D
 
Don't know about slantzilla, but I despise them because they leak oil and I haven't found a way yet to stop it. :angry5:
 
If you guys can please post pics of both heads and show us the difference. I dont know so school me if you would. Thanks
Small Block
 
Be careful what you say to Slantzilla. He will taunt you, wave his private body parts, and fart in your general direction!

I'll bet the drool tube heads are lighter than the later air injected heads. They have holes in the exhaust bowl for for that purpose and looks like it would be bad for flow.
 
Here is the head which requires the drool tubes for each plug and one (sorry bout the quality) that does not use the drool tubes

PHOT0001.JPG


PHOT0003.JPG
 
Be careful what you say to Slantzilla. He will taunt you, wave his private body parts, and fart in your general direction!

I'll bet the drool tube heads are lighter than the later air injected heads. They have holes in the exhaust bowl for for that purpose and looks like it would be bad for flow.

There isn't enough weight difference in the heads to worry about. The AIR holes are a moot point. Plug the back hole where the line used to go and call it a day.

The '75-80 heads do not have a big enough pushrod hole through them to get the lifters out if you change a cam in car though. The '81 and up heads do, if you have a steady hand. Other than that there are no drawbacks to the later heads.

I will taunt and fart, but no waving of body parts.
 
There isn't enough weight difference in the heads to worry about. The AIR holes are a moot point. Plug the back hole where the line used to go and call it a day.

The '75-80 heads do not have a big enough pushrod hole through them to get the lifters out if you change a cam in car though. The '81 and up heads do, if you have a steady hand. Other than that there are no drawbacks to the later heads.


I think I have a 83 head in the shed. Didn't know that. I do have a fresh head I ported for a friend that is 77-78 vintage.

Where do you check for the casting date?
 
Go away, Rug, or I shall taunt you a second time... :)
 
I think I have a 83 head in the shed. Didn't know that. I do have a fresh head I ported for a friend that is 77-78 vintage.

Where do you check for the casting date?

I dunno about the date, but the '81 and up head has the little dogleg in the valve cover rail by where the alternator would be.
 
Well shoot.

Something must be wrong with my drool tubes 'cause they don't leak.

:D

CJ
 
Anyone have any of the old drool tubes laying around they want to get rid of? I'll take some if you are inclined to get em out of the garage. Thanks
Small Block
 
The Super 6 with the Carter BBD also came with a 2¼ exhaust system. I think that the exhaust manifold outlet was enlarged to accomodate the larger pipe.

There were some earlier Super 6s, but I think the only thing that made them super was the fact that they were bigger and more powerful than the standard 170 CID.

The Hyper Pak was a unique animal and extremely rare. Besides the 4 barrel on the L-O-N-G ram manifold, the engine also had a 10.5:1 compression ratio. The carburetor was mounted sideways with the primaries towards the engine. The cam was a mechanical cam that on the 170 had a duration of 276-268-44º and a lift of .430". (Sorry no figures for a 225 Hyper Pak.)

According to Mopar 6 book, the 71-77 mechanical camshafts are the best regular production pieces available in general circulation.

Although not real prominent, there is an active aftermarket of products available for the /6. Attitude at SlantSix.Org isn't as laid back as here, but there is a wealth of expertise and information available on the Leaning Tower of Power.
 
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