348 Tri-Power Build gone wrong / Follow New Rebuild

427John

Well Known Member
I would post but I better let @Don Jacks do it. they are mentioned in a long private conversation.
But basically, I will be using 333 heads instead of my current 971s on my 872 block and upgrading to Hydraulic roller lifter's combo'ed with Comp Cam Extreme Energy line that they've come out with recently that comes in at 218 in. , 224 exhaust @.050
Will have to get new everything I assume for the heads. And do a little bowl work as Don mentioned. :good
Your drilling the sparkplug cooling holes in the block for use with the 333's right?
 

'37-4D

Well Known Member
Have you ever met Jim McConnell from London??? Has several 409 Bubbetops and all had 409's. He had a gray African parrot that talked like a sailor and his pet was........an alligator!! Candy and I have ridden to house several times. He had several food trucks.
No but I can ask my guys! lol
 

427John

Well Known Member
I don't know if its a must but you do gain the benefits of the cooling for the sparkplug area if you do.There must be a reason Chevy did it in the first place,maybe allows the use of a hotter plug?If so a hotter plug will be more resistant to fouling,but will become a source of detonation if insufficiently cooled.
 

nomad59NZ

Well Known Member
Supporting Member 2
Mate, just read through this post, wow this really has to bite big time. I know what it's like as do many others to go through a build on one of these engines and the costs involved with just having one completed and in my 59 wagon a few months ago.
Finding the right people to do the machining work is hard, yet thankfully i had a good one here in NZ, although chasing a couple of oil leaks at the moment.
You are talking amongst some of the great minds on 348-409 engines I know as a wealth of knowledge was passed my way when i built my engine.

A real awesome looking truck to by the way.

All the best with the rebuild.
Gav
 

'37-4D

Well Known Member
I don't know if its a must but you do gain the benefits of the cooling for the sparkplug area if you do.There must be a reason Chevy did it in the first place,maybe allows the use of a hotter plug?If so a hotter plug will be more resistant to fouling,but will become a source of detonation if insufficiently cooled.
Noted. Thx
This from @Don Jacks :
"All that will be needed to put the 817s on a non cooler block is to plug the cooling holes in the head, easy peesy. plugging those holes will have no negative effect on the engines operation what so ever"
 
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'37-4D

Well Known Member
Mate, just read through this post, wow this really has to bite big time. I know what it's like as do many others to go through a build on one of these engines and the costs involved with just having one completed and in my 59 wagon a few months ago.
Finding the right people to do the machining work is hard, yet thankfully i had a good one here in NZ, although chasing a couple of oil leaks at the moment.
You are talking amongst some of the great minds on 348-409 engines I know as a wealth of knowledge was passed my way when i built my engine.

A real awesome looking truck to by the way.

All the best with the rebuild.
Gav

Thanks for the kind words. Yes some of these guys have been at it with me from the get go!
Even got my tro manifold and carbs off a guy here :)
 

Don Jacks

Well Seasoned Member
Supporting Member 3
If the block can be drilled,some can't,then do so.If not,plug the cooling holes in the cyl.head.The cooling holes were needed for heavy load applications such as trucks and police units so Chevrolet did them all.Even with the holes in the head plugged there's some cooling because there's some coolant in the area,note the long reach plugs,where as on that early head there's none.His engine will never be loaded heavy enough for long enough to need them.
 

Don Jacks

Well Seasoned Member
Supporting Member 3
These springs when used on a set of 817's with a 1.75 installed height will give you right at 135 lbs on the seat and will coil bind at .600 ,meaning you should limit you around .560-570 max.The spring is great for a mild hyd.roller cam.
 

427John

Well Known Member
If the block can be drilled,some can't,then do so.If not,plug the cooling holes in the cyl.head.The cooling holes were needed for heavy load applications such as trucks and police units so Chevrolet did them all.Even with the holes in the head plugged there's some cooling because there's some coolant in the area,note the long reach plugs,where as on that early head there's none.His engine will never be loaded heavy enough for long enough to need them.
Don by the pics he posted at the beginning it appears his 872 block has the extra metal needed for the holes you can see where his head gasket left a nice little stain where to drill the holes.The heavy load thing makes perfect sense,and also shoots holes in the myth that the W was designed as a truck engine from the get go.
 

'37-4D

Well Known Member
While waiting for the lead shop guy to return from vacation, I thought I'd leave this right here.
The non painted truck belongs to my friend and the Hemi was built buy the guy who's working on my 348. Enjoy!!!
gcqeAwZ.jpg
 
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