Gomer Pyle
Active Member
You'll need a 62 or newer crank to run a modern TF.
413 in the 68 barracuda
- Thread starter momo61
- Start date
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Interesting, Jim checked clearance with Trick Flow 240 on a 4.250" bore using a 8519pt1 head gasket, intake interference @ .770" and the exhaust retainer hit the seal at@.850" and still didn't hit the wall.
Got a 70 forged crank
Well the barracuda has arrived form South Dakota! Currently trying to get the frozen 318 broken loose and make it mobile...thats a project!! On another note, need to make a correction on my original post as to heads i wanting to use on the 413. They are not 516' but 915's. Have a person who will sell me a set for $1000...thats chunk. If I have to spend that on cast iron I've looked into aluminum but can't locate any that have 2.08/1.74 valves. All so far are 2.14/1.81...too big for a 4.18 bore without nothing
Any suggestions outside of Summit and Mancini?
Any suggestions outside of Summit and Mancini?
The barracuda as arrived from South Dakota! Currently working on getting the 318 broken free to get the car mobile, thats a project in itself. Need to make correction to original post on 413 heads i want to use...not 516's but 915's. Have a person willing to sell me a pair for $1000, pretty steep for cast iron even if they were only made in 67. Looking into aluminum heads before I'll commit on that but can't find what I need. So fare everything has 2.14/1.81 valves. To big for a 4.18 bore without nothing the bore. Any suggestions on sourses outside of Summit and Mancini?
Some 413 blocks can be bored to 4.250".
My 413 block has been freshly bored 30 over and pistons in. Not an option at this point so need to get the head dilemma solved now.
The 413 bore is .0625" smaller then a 426 bore of 4.250"
The 413 would need a .060" overbore and finished honed to 4.250"
The 413 would need a .060" overbore and finished honed to 4.250"
What pistons are you using.
PRH
Well-Known Member
TF heads have 1.76” ex valves vs 1.81” for the ones in the 346 heads and Ede heads.
PRH
Well-Known Member
The unported Stealths I’ve worked on have had the valve job rather small for the valve sizes being used.
I’d say most of them would have worked fine taking the supplied valves and cutting them down .050” or so.
I’d say most of them would have worked fine taking the supplied valves and cutting them down .050” or so.
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Using flat top pistons. In order to get to a 10:1 CR i need to use a closed chamber head with a 78cc chamber...thats the 915 head. But of course those were only made in 67 before the 906's were came on the scene. I have a set of those but my calculations show that combination will only yield about 9 1/2:1 CR
Correction 906 combination is closer to9:1 CR as I look at my calculations
Has the block been decked?
The dilemma with the 413 is, the only piston I'm aware of is the Egge flat top which yields about 8.1 compression at the most without milling the heads.
PRH
Well-Known Member
“If it were me” I’d be mocking up a factory head with a 1.74” exhaust valve on the block and checking to see what the radial clearance is, and seeing how much lift it can take before contact.
It may not be an issue, but I’d wanna know before I firmed up my cylinder head plans.
It may not be an issue, but I’d wanna know before I firmed up my cylinder head plans.
Block has not been decked.
That 8.1 CR is low. I redid my CR calculations taking into the 30 over bore, top of piston to deck, head gasket and combustion chamber size and feel my number of 9.4 CR should be pretty spot on now. Thats still not the 10 im shooting for. To find an available 413 piston with a dome (would even be much) I don't think exists. This 413 is going to be a challenge to get what im trying to achieve.
Great advice! I want to also check how much room i have from top of piston to full open valve. I think i would rather have a piston made with enough dome to raise CR 0.6 to my target and leave everything else at factory specs...thats if I have the room to do that.
mygasser
Well-Known Member
try bolting a head onto the bare block with a couple of bolts (and a gasket) and just one pair of valves with either checking springs or no springs. then while looking up the bore from the crankcase area slide the valves down the guides into the bore to check your clearance. you can open them the amount your cam/rocker combo will give you and measure the clearance from valve head to bore. it's then easy to work out how big a valve will fit. this will help give your cylinder head choice more clarity.
neil.
neil.
Jim Lusk
Well-Known Member
516s will give higher compression than the 906s due to the smaller closed chamber design of the 516.
PRH
Well-Known Member
I think after some measurements have been taken it’s going be pretty obvious this build is going to want closed chamber heads.
There is no practical upside to using the 413 block.
If it were a finished short block that would satisfy your needs that would be one thing, but to pour money into it makes no sense to me.
Just save yourself some $$$/headaches and find a 440 block.
My .02….
There is no practical upside to using the 413 block.
If it were a finished short block that would satisfy your needs that would be one thing, but to pour money into it makes no sense to me.
Just save yourself some $$$/headaches and find a 440 block.
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LST46
Well-Known Member
Agreed. You could even go the route of finding a 400 block and just doing a stout 400 build or better yet put a 440 crank in it and build a 451. The low deck will be a bit easier to work on in a small A-body engine bay. Just my .02
middleagecrisis
Well-Known Member
If you’re set on 10-1 compression then you should seriously consider decking your block to get you to minimal piston/ deck clearance. I scanned through the post again and didn’t see where you had decided on pistons. As a point of reference, I decked my 360 block.095 to get my pistons at .005 deck and my heads and intake will still bolt up without any additional milling of the intake manifold. Of course, that was my combination of parts. I paid $200 to my Machine Shop to do that big cut on my block, so it’s definitely something for you to consider rather than paying a huge amount of money for the only heads it will work in your current combination.
33IMP
Well-Known Member
I have NOT read this whole thread, and my point may have already been covered, but I'm gonna comment anyway.
Your head choice WILL be guided by the pistons you can find for a 413, assuming you won't be buying a set of mega dollar custom pistons for it. You'll need to calculate compression ratio carefully, for each head you might want to use, to get a compression ratio you can live w8th.
Your head choice WILL be guided by the pistons you can find for a 413, assuming you won't be buying a set of mega dollar custom pistons for it. You'll need to calculate compression ratio carefully, for each head you might want to use, to get a compression ratio you can live w8th.
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