380 build

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ChevyCentral

New Member
Happy New Year everyone! I am really hoping to get your expertise as I am looking to build my 1st 348 into a 380. The block is at the machine shop, getting inspected and bored .030 over. I believe I have sourced a 409 crank. I plan on running 3x2's and a 4 speed in my '59 Impala and hoping to get close to 400hp, as that's about all the carbs can deliver. I have read several posts that suggest I can use 6.135" rods from a later BBC with custom pistons. Can someone help me with this build??
Are these the rods I need? Same bearings? Where do I get the custom pistons? Is there a formula for the pistons or do they know what dimensions of what they should be? Is there a good cam to use? The heads are 333, should I port them, and if so, is there a place I should send them? Are the any other modifications I need to perform to the heads? Any suggestions you have would be greatly appreciated, as reading all the posts has got me more confused to what I should do.
TIA!!
 
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Don Jacks

Well Seasoned Member
Supporting Member 3
Hi,In order to use 6.135 rods in a 380,you'll have to resort to using Ross or other aftermarket custom pistons[more expensive than you need for this power level].If you get with Show Cars,you can get one of two Icon forged pistons[over 200 dollars cheaper].One would be the stock stroke replacement piston and pair them with the 409 length rod[6.10],the other for the 4 inch stroke crank,and pair them with the 6.385 aftermarket big block rod.The second option will give you a compression ratio of about 10.25,the first option closer to 10.75.I recommend the second option for iron heads.As to the 333's,add bigger valves[2.09 in,and 1.72 ex.],and a bowl blend and a good valve job.Your cam would be some thing in the 224-228 intake,230-235 duration at .050,lobe seperation in the 110-112 range,4 degrees advance ground in will help.Howards Cams has a flat tappet hyd.in that range,as does Comp Cams thru show Cars[pn 0951],but the Comp grinds are,in my opinion,crrazy expensive.The lift will be around .525 or so.This package will meet or slightly exceed your hp expections and the torque will blow you away.
 
OkieJoe29

OkieJoe29

Well Known Member
I’m doing the same build, I went with the 6.385 and 4” stroke pistons. Didn’t want too much compression. Hemi had a complete Tri power setup I was going to use until I came across a 6x2 at a swap meet with Holley 94’s on it. Went with a Howard’s 229/233 hydraulic roller setup so I’ll have to take a little off the notch but got the valve cutting tool to do it. I have a Muncie M20 rebuilt waiting for the engine lol. I like your style!
 
Rickys61

Rickys61

Well Known Member
Supporting Member 3
When I built mine in 2014 I used the 6.135 big block rods just because I had them already. Ordered custom Ross pistons from Show Cars. Mine runs pretty good…. If I had it to do over I would go with Mr Jacks suggestion with the 6.385 rod and Icon pistons…
Rick
 
Tom Kochtanek

Tom Kochtanek

Well Known Member
Supporting Member 13
1961 FA 348 block dated "G 60" with standard 409 crank, .060" Ross pistons, BBC rods on the bottom.

Same date 1147s with screw in studs, roller rockers and big valves, triple twos up top. Correct valve covers for big air cleaner.

Not yet fired up, the hard part is getting the body ready to receive her :(.

Don hates those HP sucking single pod air cleaners, so I took 'em off :).

TripleTwos.jpg
 
C

ChevyCentral

New Member
I picked up a very clean 409 crank (8019) today, I am hoping it doesn't need much work. I was talking to the guy I got it from and was wondering if there is a way to eliminate the vent tube on the rear of the intake? Would a catch can work or is there a better idea?
Are there any good videos on porting the 333 heads that anyone knows of, or should they be done by someone that knows these heads?
 
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Don Jacks

Well Seasoned Member
Supporting Member 3
Show Cars makes a pcv valve aet up for the 3-2 set up that you plan to run.For no more power than you want,a speciallest in't really necessary.Where do you live?
 
Tom Kochtanek

Tom Kochtanek

Well Known Member
Supporting Member 13
Don: You should show him the bowl work done by Ronnie Russell on those 333s :). Warning, Ronnie told me he had maybe 30+ hours in opening things up on those truck heads (and several carbide tips) !!!

Others have done this and I suspect there might be a thread from the past that offers some detail?

Go for it! TomK
 
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Don Jacks

Well Seasoned Member
Supporting Member 3
Tom.those heads that Ronnie did,in my opinion,will support about 500 hp .That's more work than he nededs for the 400 or so that he's shooting for.If he wants more,he should look up Yellow wagon's "409 truck motor" build.Ronnie guided Jason on the 333 heads .For what he wants,install 2.06 in.1.72 ex valves,bowl blend ro 90 percent of seat diameter,and o a good multi angle valve job.Those heads that Ronnie did MIGHT be available for sale.
 
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