XfbodyX
Well-Known Member
Did the passenger car roller cam heads have hardened seat inserts in them?
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Who has torn apart a 85 up roller 318?
- Thread starter XfbodyX
- Start date
kkritsilas
Well-Known Member
Almost all engines built after 1974 had hardened valve seats. usually induction hardened, as opposed to valve seat inserts.
Aspen500
Well-Known Member
I concur. If the engine was built to burn low lead and/or no lead gasoline, the exhaust seats are hardened.
Oldiron440
Well-Known Member
I believe it started in 72.
XfbodyX
Well-Known Member
Ummm yes I know this, that is why I specifically asked if they had "hardened seat inserts".
Im thinking thats what set the truck heads apart from the passenger car heads as inserts are better in the long run then the induction process. Also the induction hardening at times only went .030 and a steel valve after time will pull small particles (it will stick to the valve) and thats how you end up with the sunken valves.
With the induction hardened seats a SS valve wont have the sticking issue that a steel valve will.
See the factory insert here.
So back to my original question, Did the passenger car roller cam heads have hardened seat inserts in them? Id guess not at this point and also why the truck head is not approved for NHRA stock.
Im thinking thats what set the truck heads apart from the passenger car heads as inserts are better in the long run then the induction process. Also the induction hardening at times only went .030 and a steel valve after time will pull small particles (it will stick to the valve) and thats how you end up with the sunken valves.
With the induction hardened seats a SS valve wont have the sticking issue that a steel valve will.
See the factory insert here.
So back to my original question, Did the passenger car roller cam heads have hardened seat inserts in them? Id guess not at this point and also why the truck head is not approved for NHRA stock.
Aspen500
Well-Known Member
Ahhhhhhhhh, I see said the blind man to his deaf wife, NOW I get what you were asking and,,,,,,,,,,,have no idea, sorry
kkritsilas
Well-Known Member
Most inserts are not factory. There may be some, but the factories induction hardened the seats as part of the head manufacturing process. There was no reason to take extra labour time and put in inserts when the heads were already induction hardened.
I don't think any 318s ever had factory inserts, from 1972 on.
I don't think any 318s ever had factory inserts, from 1972 on.
Oldiron440
Well-Known Member
Now that I understand what your talking about I will ask my head expert tomorrow, he's is very familiar with all things mopar.
XfbodyX
Well-Known Member
Ok, to clear the insert issue up and try not to sound like a smartass , these are from the box mopar heads with the seat inserts, they are HD truck heads. Mostly used by the army. So I know what mine are, I just wondered if the 85 pass cars had the inserts but if id of thought ahead id of known they had the induction hardened type. Ive still another 3 sets of these sealed in the boxes.
I don’t recall seeing any new heads with inserts cut into them already – but to be honest, I don’t recall looking for that aspect. I can see factory rebuilt heads with new seats or a possible usable new head that wasn’t cast correctly, cut to have an insert installed so new part would be useable.
I was wondering, can you get me the part numbers on those boxes, please?
For car, pickup and van usage (’70-80’s), I think the cylinder heads were pretty much the same across the board – depending on emission usage.
That said, I have a pair of ’79 360 motor home heads which are weird. It uses huge spark plugs, 360 exhaust ports, 360 combustion chambers but 318 intake ports. I hadn’t measured the valves but appear to be the smaller 318 valves. To make it even more odd, it had a 360 4-bbl intake on it which had a huge step between the 318 head (intake) port and 360 intake. All the (’70-80’s) small blocks were made at either Windsor, Canada or Detroit Michigan (Mount Road) assembly plants (depending if to be installed into a Canadian or US made car) – except for most motor home engines which were built in Trenton Michigan.
Also, I have no idea if military spec engine parts are different - which might be part of the difference (me shrugs).
BudW
I was wondering, can you get me the part numbers on those boxes, please?
For car, pickup and van usage (’70-80’s), I think the cylinder heads were pretty much the same across the board – depending on emission usage.
That said, I have a pair of ’79 360 motor home heads which are weird. It uses huge spark plugs, 360 exhaust ports, 360 combustion chambers but 318 intake ports. I hadn’t measured the valves but appear to be the smaller 318 valves. To make it even more odd, it had a 360 4-bbl intake on it which had a huge step between the 318 head (intake) port and 360 intake. All the (’70-80’s) small blocks were made at either Windsor, Canada or Detroit Michigan (Mount Road) assembly plants (depending if to be installed into a Canadian or US made car) – except for most motor home engines which were built in Trenton Michigan.
Also, I have no idea if military spec engine parts are different - which might be part of the difference (me shrugs).
BudW
XfbodyX
Well-Known Member
I will get the pn Bud, but you can see the casting number, they are HD 318 truck heads that have the same port config as a 302 head and come in both std or roller cam version for the larger diameter pushrod hole RC pushrod angle with the rasied lifter.
4343723 85-91 318
I like the std flat tappet la version because you can take the whole pushrod protrusion in the port out because, oddly though they have PN on the head.
Im gonna do some actual chamber work but I just put a set of 1.88 intakes and left the 1.50 exhaust and filled them with costly stainless steel valves. (hard to find 1.88 stainless 3/8 stem intakes and hard to find the 1.50 ex because of low demand) I was able to machine cut the bowls and then finish them off by hand to mimic a 1.88 J head bowl/throat and used the pinch area to get the csa I was shooting for and to control the velocity there vs the throat.
The appeal to me was the seats and the cost being low for a new casting, although I didnt get mine off ebay, still a good deal vs reman costs.
I recall seeing them in the Army with the inserts and never thought different because most HD and industrial heads that pull a load have inserts for longevity.
You can see in the pics above the larger diameter pushrod holes vs the set in my pic below with the smaller std oem size. And still both heads with the same PN and casting number, one early military use, one later.
Actually mopars are known to have hardened seat inserts in HD truck motors even back to the early truck hemi-s, the 331 and 354. And id bet others.
MOPAR OEM 318/360 CYLINDER HEAD; 4343723 | eBay
4343723 85-91 318
I like the std flat tappet la version because you can take the whole pushrod protrusion in the port out because, oddly though they have PN on the head.
Im gonna do some actual chamber work but I just put a set of 1.88 intakes and left the 1.50 exhaust and filled them with costly stainless steel valves. (hard to find 1.88 stainless 3/8 stem intakes and hard to find the 1.50 ex because of low demand) I was able to machine cut the bowls and then finish them off by hand to mimic a 1.88 J head bowl/throat and used the pinch area to get the csa I was shooting for and to control the velocity there vs the throat.
The appeal to me was the seats and the cost being low for a new casting, although I didnt get mine off ebay, still a good deal vs reman costs.
I recall seeing them in the Army with the inserts and never thought different because most HD and industrial heads that pull a load have inserts for longevity.
You can see in the pics above the larger diameter pushrod holes vs the set in my pic below with the smaller std oem size. And still both heads with the same PN and casting number, one early military use, one later.
Actually mopars are known to have hardened seat inserts in HD truck motors even back to the early truck hemi-s, the 331 and 354. And id bet others.
MOPAR OEM 318/360 CYLINDER HEAD; 4343723 | eBay
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XfbodyX
Well-Known Member
Your killen an old mans back and legs here Bud 
The military tag below is the first pic, also showing more pics of same casting with diff pushrod hole diameters.
And if you think about it, what better head for a cheap turbo build or even a propane conversion since propane is high heat ex temps.
The military tag below is the first pic, also showing more pics of same casting with diff pushrod hole diameters.
And if you think about it, what better head for a cheap turbo build or even a propane conversion since propane is high heat ex temps.
Oldiron440
Well-Known Member
XfbodyX
Pardon me for my small block ignorance here but. why didn't you use a valve with a standard stem that is reduced between the head and guide.
I'm not aware of the difference in friction generated between the two diameters or weight but if cheap is what your after you could cut down the larger size also?
Pardon me for my small block ignorance here but. why didn't you use a valve with a standard stem that is reduced between the head and guide.
I'm not aware of the difference in friction generated between the two diameters or weight but if cheap is what your after you could cut down the larger size also?
XfbodyX
Well-Known Member
You mean like the two on the left vs the oem full 3/8 stem on the right?
I had thought about cutting some down but not sure if you knew or not, im losing the ability to stand/walk so when I can stand and walk I need to use my time wisely. I cant sit at my lathe I got to stand to do things.
All in all over weight of the SS intake and exhaust is 5 grams less then if I kept the oem1.77/1.50 in the picture and 5 grams heavier with the oem 1.88 and 1.50 combo.
Like I mentioned in the PM the other night if I really wanted to go big I would of pressed in 3/32 or 8mm guides and used cheaper valves. But im only willing to go so far on this deal here.
I had thought about cutting some down but not sure if you knew or not, im losing the ability to stand/walk so when I can stand and walk I need to use my time wisely. I cant sit at my lathe I got to stand to do things.
All in all over weight of the SS intake and exhaust is 5 grams less then if I kept the oem1.77/1.50 in the picture and 5 grams heavier with the oem 1.88 and 1.50 combo.
Like I mentioned in the PM the other night if I really wanted to go big I would of pressed in 3/32 or 8mm guides and used cheaper valves. But im only willing to go so far on this deal here.
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Oldiron440
Well-Known Member
I see, I'm just sitting here with one eye open and need to go up to bed a just started thinking.
Why are you losing your mobility?
Why are you losing your mobility?
XfbodyX
Well-Known Member
The Clap, but worse.
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Oldiron440
Well-Known Member
Sorry to hear that.
Thank you XfbodyX!
MOPAR OEM 318/360 CYLINDER HEAD; 4343723 | eBay
I think the eBay listing is misleading. It says “MOPAR OEM 318/360 CYLINDER-HEAD; 4343723”. So (rhetorically) which is it, a 318 or a 360 head? No view of the intake ports. The exhaust port looks like a 360 – but I can’t reliably tell the difference from the exhaust port. Intake yes, but not on exhaust. I would not be a happy camper, if I bought this head for a 340/360, sense it is advertised “360”, and it arrives with 318 ports.
You said it was for a 318 – so have no reason to disagree with you (just the person with the eBay listing).
I’m still somewhat mobile, but that is going downhill quick. A couple of years ago, my kids ran over my ankle/heal with a shopping cart, hard. 2 days later, they ran over the other ankle/heal with a shopping cart. A short time later, I found out I have spikes growing out of back side of heal and pushing into Achilles tendon (might have been bone fragments breaking away from the heal, then growing back funny). I have to keep my feet at a 90 degree angle when at rest (sitting or sleep), for if I don’t, the tendons swell the size of a golf ball (and I can’t walk - or even get shoes on). Even when I keep it correct, I can’t stand or walk for long periods (like I could a couple of years ago).
It sucks when your body starts to complain (a lot) when you ask it to do something.
BudW
MOPAR OEM 318/360 CYLINDER HEAD; 4343723 | eBay
I think the eBay listing is misleading. It says “MOPAR OEM 318/360 CYLINDER-HEAD; 4343723”. So (rhetorically) which is it, a 318 or a 360 head? No view of the intake ports. The exhaust port looks like a 360 – but I can’t reliably tell the difference from the exhaust port. Intake yes, but not on exhaust. I would not be a happy camper, if I bought this head for a 340/360, sense it is advertised “360”, and it arrives with 318 ports.
You said it was for a 318 – so have no reason to disagree with you (just the person with the eBay listing).
I’m still somewhat mobile, but that is going downhill quick. A couple of years ago, my kids ran over my ankle/heal with a shopping cart, hard. 2 days later, they ran over the other ankle/heal with a shopping cart. A short time later, I found out I have spikes growing out of back side of heal and pushing into Achilles tendon (might have been bone fragments breaking away from the heal, then growing back funny). I have to keep my feet at a 90 degree angle when at rest (sitting or sleep), for if I don’t, the tendons swell the size of a golf ball (and I can’t walk - or even get shoes on). Even when I keep it correct, I can’t stand or walk for long periods (like I could a couple of years ago).
It sucks when your body starts to complain (a lot) when you ask it to do something.
BudW
Oldiron440
Well-Known Member
The worst thing about the hill is it's got a curve and gets steeper toward the bottom.
XfbodyX
Well-Known Member
It is a mis leading ad on ebay, but id hope many would know there is no universal 318/360 head. As I posted up above they have the same intake port as a 302 head, they are the same as a 302 head except for the open chamber. Probably would choke a 360 out at 4k.
I did get a couple sets of heads like the #308 that do have 360 ports, but mainly the Army at least liking uniformity mostly used the 318.
I forget the out of box port volume but it was right there with the lowest number a small block head could pop out, thinking I recall an older 318 being 125 cc, these were like 112 and I ended up with a hair over 160 and the math says things done will support up to 6k rpm. It would be alot harder to get the roller cam head version to that number. Ive pared these with a .500 solid cam and a good bit of compression.
I did get a couple sets of heads like the #308 that do have 360 ports, but mainly the Army at least liking uniformity mostly used the 318.
I forget the out of box port volume but it was right there with the lowest number a small block head could pop out, thinking I recall an older 318 being 125 cc, these were like 112 and I ended up with a hair over 160 and the math says things done will support up to 6k rpm. It would be alot harder to get the roller cam head version to that number. Ive pared these with a .500 solid cam and a good bit of compression.
