Restarting my 348 project!!

Tim

Well Known Member
Supporting Member 4
Hi guys! I fell off the radar for a bit, nasty divorce stuff and all in the past now and she didn’t get my car!!! However everything got put on hold after i got the 409 crank from Tom because of it but i put everything in storage out of sight. On top of that my original 66 SS shell got smashed in a windstorm! I bought another one and now revisiting the 348/409 build. I'm starting to collect the parts I need and need a little help. I wrote down the list from a couple of years ago to go with the crank I got from Tom #3788072, it’s ground 30/30. Here’s the list I wrote down. Bore 30 over, KB Pistons 11-1, seems to be alot of options Valve Pockets?? forged etc., rods 6.385 or 6.135? Comp 0951 Cam, solid or Hydraulic Lifters? i know when i fit the Crank in the 348 block the 348 pistons would hit the counterweights on the crank. i'll also buy a set of heads as the ones that were on the 348 are 555 small port and valves. remember this is a double notch block and im trying to get 400HP or close to it. hope all is well take care. good to be back
 

Tim

Well Known Member
Supporting Member 4
I’m thinking they have to be 817,690 or 1147’s. these all have the big valves. My last option is aluminum Edelbrock but they are expensive.
 

models916

Well Known Member
Supporting Member 7
333 has the same size valves as the 817, 1147 from what I remember. Much cheaper as a starting point as everything should be changed out. Opinions on this could change because of the double notch block and the 333 has a small chamber. What is the final compression you are looking for?
 

scott hall

Well Known Member
Supporting Member 2
Don't think you will want 690 or edelbrocks unless you wing it pretty good. 348 won't move good air until high RPM. 1147 would probably be best but kinda hard to find and usually not cheap.
 

Tim

Well Known Member
Supporting Member 4
Models, from memory I’m thinking it will come in around 9-9.5 -1. Don Jacks might be able to chime in
 

Don Jacks

Well Seasoned Member
Supporting Member 3
333 has the same valve as the 379 and other'"standard passenger car and truck heads-1.94 in.,1.67 exhaust.Jim Sullivan is building a double notch block,348 stroke,and 10.5 cast pistons.It came in at around 8.8.With the 1/4 inch longer stroke of the 409 crank,it would be a little over 9 if you used the K-B piston pn 8935 and the stock length 409 rod.Jim's using 817 heads.
 
Last edited:

Jim Sullivan

Well Known Member
Supporting Member 10
:yup I type too slow.

I am building a double notch 348. I am only using 10.5 to 1 cast pistons. With these pistons and .030 off the block deck and 817 heads, I'm just under 9.0 to 1 compression ratio. With your selection of pistons, my guess, you should be around 9.5-1 depending on what head gasket you use.
 

Don Jacks

Well Seasoned Member
Supporting Member 3
Oh by the way,other than overszes,KB pistons are off the shelf,meaning no options as to valve depths.The 0951 cam is a hyd.flat tappet cam and the K-B's notches are plenty deep enough.If you go to Ross or others,you can pretty much get anything that you'd want,but It'll cost you.
 

Tim

Well Known Member
Supporting Member 4
All great info. It’s good I’ll be able to use my stock 348 rods with the 409 crank. 1 less thing I need. I’ll look for a set of 817 heads. The 555 heads I have are good paperweights and maybe rob the rockers off them. Block is going for bore and decking then the fun begins!
 

Tim

Well Known Member
Supporting Member 4
I knew the 409 rods were shorter but thought the piston compensated, glad I didn’t make that mistake. I’ll get 409 rods to go with the crank. Having pistons hitting the heads never ends well!
 

Tom Kochtanek

Well Known Member
Supporting Member 12
I would look into a good set of "off-the-shelf" rods, as you'll spend around $300 to have used 409 rods R&R'd. For that amount you can get a good set of 6.135 rods.

In my 348 stroker I went with the 409 crank, BBC rods (6.135") and custom Ross pistons. I am using the 1147 heads. I think you can substitute KB-Icon pistons in that combination, but I'd check to be sure.

Good luck with your build!

TomK
 

models916

Well Known Member
Supporting Member 7

Don Jacks

Well Seasoned Member
Supporting Member 3
If you use the K-B piston for the stock stroke 348[ Show Cars pn 8935],you'll need Show Cars pn 7225s 6.09 [stock 409 length] rod.If you use the K-B piston pn 7815,you'll need a 6.385 length rod.The 6.135 length rod will not work with either K-B piston for this combination.Each has pluses and minuses.You can get a Ross piston that will work for the 409 crank and the 6.135 rod,but it'll cost you at least 200 dollars more for the pistons.
 

Tom Kochtanek

Well Known Member
Supporting Member 12
Don is correct in that the KB-Icon pistons are the least expensive way (with new parts) to build a stout 348 stroker.

I got lucky in my build, the block needed .060" to clean up (1961 FH block) and I found a seller who had that exact set of Ross pistons in stock (for the 6.135 BBC rods) for only $600. So I jumped on them and hung them on BBC rods and a 409 crank. With 1147 heads, a strong cam, and tripower it should look good and perform well. Currently in moth balls awaiting project initiation (and a pile of cash!). It's destined for a certain 1961 Belair sport coupe :).

Cheers! TomK
 

models916

Well Known Member
Supporting Member 7
333 has the same valve as the 379 and other'"standard passenger car and truck heads-1.94 in.,1.67 exhaust.Jim Sullivan is building a double notch block,348 stroke,and 10.5 cast pistons.It came in at around 8.8.With the 1/4 inch longer stroke of the 409 crank,it would be a little over 9 if you used the K-B piston pn 8935 and the stock length 409 rod.Jim's using 817 heads.
Some of the stock 348 heads had small ports. 333 has larger ports like 817...
 
Top