198 slant questions

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Johnny71dusty

Johnny71dusty

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I’ve read lots of threads on how to identify and basically you can’t . My car I believe to have its original 198 in it . I snapped my studs off in it trying to replace my intake and exhaust so thinking I’m gonna just buy one. But no one seems to sell a head for 198 specifically. I’ve not seen on the threads about anyone talking about any head differences on the 3 slant engines. Does it matter ?
 
No they are all the same unless its a peanut plug compared to a drool tube.
 
Hydraulic head had a different valve cover but that was a very late model slant.
 
Johnny71dusty said:
Perfect answer and thank you. If I order a slaughterhouse shaved 225 head it will be fine if it’s a 225 or a slant . All I needed .
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Just make sure to get the year model correct and it's the right one. Give them the casting number. Even if it's a different casting, as long as it has spark plug tubes and it's a 68 and later casting, it's the same.
 
RustyRatRod said:
Just make sure to get the year model correct and it's the right one. Give them the casting number. Even if it's a different casting, as long as it has spark plug tubes and it's a 68 and later casting, it's the same.
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It’s 71 and it’s cast say 225 but they all say that lol . Car tag says it’s - 198 car so who knows most every 198 I’ve heard or seen says it’s a 225 . I don’t care not looking for any performance just a head with not studs snapped off in it
 
Are they flush it is there any stick out?
I'd be inclined (worse case) send it to the machine shop and have them redo that head, and put it in the mill and drill out the bad ones, a common process.
Measure your piston in the hole depth while off and have em cc it and shave the head while there.
I mean this one ran ok on there all this time, right? So you know it most likely ain't cracked, etc.
You will probably come out ahead money wise, especially if that replacement head has to be shipped. I've bought several parts this year where shipping was as much (and on a couple, more)$$ than the price of the part itself.
 
Perfect answer and thank you. If I order a slaughterhouse shaved 225 head it will be fine if it’s a 225 or a slant . All I needed .
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Your welcome! I have a '60 slant head and it has no alternator/generator bolt boss. They were mounted on the pump side back then.
 
volaredon said:
Are they flush it is there any stick out?
I'd be inclined (worse case) send it to the machine shop and have them redo that head, and put it in the mill and drill out the bad ones, a common process.
Measure your piston in the hole depth while off and have em cc it and shave the head while there.
I mean this one ran ok on there all this time, right? So you know it most likely ain't cracked, etc.
You will probably come out ahead money wise, especially if that replacement head has to be shipped. I've bought several parts this year where shipping was as much (and on a couple, more)$$ than the price of the part itself.
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Oh it’s ran amazing until today I snapped two stuff off in it . Just thought buying new one with .08-.100 off it already was the way to go
 
Won't your push rods also need to be shorter or is there enough adjustment
 
HAWAII is looking for a head. Can get it to a container shipper via California. Check want ads
 
You ought to be able to measure the stroke and tell what engine it is.
 
Johnny71dusty said:
Guys often take .100 of head and .100 off block and still nothing hits . Lol I’m thinking .100 of head is fine and very little risk especially with new head gaskets as thick as they are
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I haven't seen anyone talking about piston to valve clearance yet, until you brought it up. We were discussing how you can take lots of material off and still get decent valve adjustment. I don't know if it's possible to make a 225 or 198 make piston to valve contact by milling. I guess it's possible. I know on the 225 in Vixen right now, the deck clearance was .175 in the hole. Ridiculous. I had the head milled to get the chambers from 56cc to 34cc. That was well over .155". This engine has a tic over 175 cranking pressure. On a slant 6.
 
RustyRatRod said:
I haven't seen anyone talking about piston to valve clearance yet, until you brought it up. We were discussing how you can take lots of material off and still get decent valve adjustment. I don't know if it's possible to make a 225 or 198 make piston to valve contact by milling. I guess it's possible. I know on the 225 in Vixen right now, the deck clearance was .175 in the hole. Ridiculous. I had the head milled to get the chambers from 56cc to 34cc. That was well over .155". This engine has a tic over 175 cranking pressure. On a slant 6.
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I have a 74, 225 here on a stand that I am slowly putting together as time allows, and even after a 30-thou deck shave, my pistons are STILL at 180 thou in the hole. I'm not really happy about that. It has 20-over silv o lite stock style replacement pistons in it on a set of NOS OEM Mopar rods I found via a guy over at the /6 forum.
I started with a head a block and a crank. Didn't get Pistons or rods with it when I got it or I'd have measured how deep in the hole the originals were.
So if I hadn't asked for that deck shave they would have ended up .210in the hole. Really ridiculous huh?
One of the magazine articles I read on the /6 had a fresh engine with Pistons at .210 in the hole. I think it was an article about the red 67 dart at the college in PA. There have been a few written about that one.
I've heard it said that replacement piston makers make the compression height less to compensate for the (slight) potential CR increase from boring out a cylinder. Which might be/ but is even made more ridiculous when you consider that when actually measured out/"blueprinted" as they come from the factory they aren't anywhere near advertised compression ratio to begin with due to all the tolerances of an assembly line.
 
volaredon said:
I have a 74, 225 here on a stand that I am slowly putting together as time allows, and even after a 30-thou deck shave, my pistons are STILL at 180 thou in the hole. I'm not really happy about that. It has 20-over silv o lite stock style replacement pistons in it on a set of NOS OEM Mopar rods I found via a guy over at the /6 forum.
I started with a head a block and a crank. Didn't get Pistons or rods with it when I got it or I'd have measured how deep in the hole the originals were.
So if I hadn't asked for that deck shave they would have ended up .210in the hole. Really ridiculous huh?
One of the magazine articles I read on the /6 had a fresh engine with Pistons at .210 in the hole. I think it was an article about the red 67 dart at the college in PA. There have been a few written about that one.
I've heard it said that replacement piston makers make the compression height less to compensate for the (slight) potential CR increase from boring out a cylinder. Which might be/ but is even made more ridiculous when you consider that when actually measured out/"blueprinted" as they come from the factory they aren't anywhere near advertised compression ratio to begin with due to all the tolerances of an assembly line.
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Well, you can hunt up some 198 rods, or buy some Molnars and use the 2.2 style pistons.
 
volaredon said:
I have a 74, 225 here on a stand that I am slowly putting together as time allows, and even after a 30-thou deck shave, my pistons are STILL at 180 thou in the hole. I'm not really happy about that. It has 20-over silv o lite stock style replacement pistons in it on a set of NOS OEM Mopar rods I found via a guy over at the /6 forum.
I started with a head a block and a crank. Didn't get Pistons or rods with it when I got it or I'd have measured how deep in the hole the originals were.
So if I hadn't asked for that deck shave they would have ended up .210in the hole. Really ridiculous huh?
One of the magazine articles I read on the /6 had a fresh engine with Pistons at .210 in the hole. I think it was an article about the red 67 dart at the college in PA. There have been a few written about that one.
I've heard it said that replacement piston makers make the compression height less to compensate for the (slight) potential CR increase from boring out a cylinder. Which might be/ but is even made more ridiculous when you consider that when actually measured out/"blueprinted" as they come from the factory they aren't anywhere near advertised compression ratio to begin with due to all the tolerances of an assembly line.
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so just cut the head a bunch to get to your desired compression ratio, cc the chambers so you know where you are starting from, then use an on line compression calculator to determine the cc's that get you where you want to be. Each .0069 cut removes one cc. Although the cc reduction increases a bit as you deeper into the combustion chamber due to the angle of the walls. You are using a large bore gasket, so remember to include that diameter in the calculations.
 
Yup. Got what I need to cc the head, just gotta do it.
I have already had 70 thou shaved from the head if the machine shop listened to me.
Didn't post my last one as a question as much as it was for info related to what was posted before, in this thread/ so they can see what we're all up against in getting what we want from our machine, not everyone has the same"wants" from theirs as everyone else does
 
RustyRatRod said:
Well, you can hunt up some 198 rods, or buy some Molnars and use the 2.2 style pistons.
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Maybe on the next one. This one "is what it is" at this point. The only thing more I might do to it once I get the head cc'd is to maybe have some more taken off there.
Probably not gonna happen but still have it in my head that I *might* do a backyard homebrew turbo "some day" on it. Between the block and head I have had a combined .100" shaved at this point but to use the head I did up for 'this' motor I'm gonna have to run the thick 60-thou head gasket, (talked about that before) which is 40-thou thicker than OEM was, so my 100- thou shave job will only yield 60-thou thinner than what this engine was originally.
Don't wanna take away from the OP anymore than has already been done but not knowing how much reading he has done with older posts, trying to give him one take on what he might be able to accomplish with WHAT he has. He needs to look at some of our old threads for other ideas.....
As for mine, it has to run better than it originally did from new with the head and deck shave, plus the porting job, bored and matching oversized parts so tolerances brought back within specified range, reground cam installed, and a switch to a super 6 setup

But then again the fact that I am building a truck engine, what I want out of it might be different from what this guy with the duster might want for his.
Just 1 idea here, more than 1 way to skin a cat
 
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