Finally the decision has been made.

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toolmanmike said:
If you're building the bottom end why not just have it balanced. (you should anyway) and then everything will be neutral. (balancer, flex plate and converter.)
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$$$$ money
I did alot of research on piston weights and pin weights and the 116 speed pro pistons .030 over weight exactly the same as a standard 360 dish (factory) piston. That was the best case scenario for my budget. I talked to the machinist he is gonna charge me 190 to clean bore and hone my block. I'm doing the cam bearings and freeze plugs and reassemble (and the strip down also) he said a typical balance cost average of 250-350 dollars. So that break my budget. Right now I have 450 dollars to spend.
So the machining 190 plus the pistons 290 is 480 I'm already above that. Lol but I can save some more between now and then he said he wont get to it till after Christmas.
Then I'm gonna have to save again for the top end. It is looking like I'm gonna have to get my head machined for the cam I selected. So that's more.
 
dartfreak75 said:
Yes valve seals
Read my previous post.
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You machine the top of the guide down for more clearance at full lift. Usually the machining accepts Teflon seals. What's the .127 clearance you were talking about?
 
toolmanmike said:
You machine the top of the guide down for more clearance at full lift. Usually the machining accepts Teflon seals. What's the .127 clearance you were talking about?
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The thickness of the umbrella seal. The difference between the two max lift measurements with and without the seal.
 
You can buy the valve seat and guide cutters from Comp Cams on Summit Racing website and do it yourself. That way you can use the Teflon seals and have the clearance you need, and save you some cash.
 
Jax340Dart said:
You can buy the valve seat and guide cutters from Comp Cams on Summit Racing website and do it yourself. That way you can use the Teflon seals and have the clearance you need, and save you some cash.
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I checked them out I think that it would be cheaper just to have it done those cutters are not cheap
 
Jax340Dart said:
You can buy the valve seat and guide cutters from Comp Cams on Summit Racing website and do it yourself. That way you can use the Teflon seals and have the clearance you need, and save you some cash.
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Did you do yours yourself?
 
IIRC the guide cutter is 60 the spring seat cutter is 75 and the arbor is like 30
 
dartfreak75 said:
I think your right. At that installed height I would need to cut the guides down .135 to get a max lift of .515
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I would never cut the spring seats unless I had to for diameter. I never cut them going DOWN into the head. It's pretty thin there in relation to the water jacket. All I ever recommend there is enlarging the diameter......but unless you're running a really big solid, or a roller of some kind, 9 times out of 10 you can get by with a stock diameter spring.
 
If I take the max lift number (with seal) 1.16 and subtract .135 from the guides that gives me 1.025 minus the installed height 1.64=.615 - .100 clearance leaves me a max lift of .515 that's right on the money for my cam. I should probably cut the guides .14 just to be safe tho.
 
I don't think it would hurt. But.......and this is simply MY personal opinion here, so take it for what it's worth, but I don't like Teflon seals on the street. I prefer the Viton rubber. I've just had better luck with them. That's just my personal opinion, like I said. Teflon seals are geared more towards race oriented engines. I would even rather run a standard old umbrella rubber seal on the street instead of Teflon. Course, opinions vary. I do agree though, you should probably cut the guides down a little.
 
RustyRatRod said:
I don't think it would hurt. But.......and this is simply MY personal opinion here, so take it for what it's worth, but I don't like Teflon seals on the street. I prefer the Viton rubber. I've just had better luck with them. That's just my personal opinion, like I said. Teflon seals are geared more towards race oriented engines. I would even rather run a standard old umbrella rubber seal on the street instead of Teflon. Course, opinions vary. I do agree though, you should probably cut the guides down a little.
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I agree with you and the umbrella seals for I think it would just be simple. I'm pretty sure I can cut the guides down that much by hand (dremal and a file) just use the umbrella seals ( I have new ones already so that saves money lol)
 
dartfreak75 said:
Iv seen used and new ones that look like mine do they all balance out the same tho?
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No, there 340 cast crank and 360 LA balancers, which are different. IIRC there are balanced dampers with weight kits that can be used to duplicate the 340 cast crank or 360 LA balancers.
 
RustyRatRod said:
I don't think it would hurt. But.......and this is simply MY personal opinion here, so take it for what it's worth, but I don't like Teflon seals on the street. I prefer the Viton rubber. I've just had better luck with them. That's just my personal opinion, like I said. Teflon seals are geared more towards race oriented engines. I would even rather run a standard old umbrella rubber seal on the street instead of Teflon. Course, opinions vary. I do agree though, you should probably cut the guides down a little.
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I do have a question about the original seals are they supposed to stay locked down on the guides or do they move up and down with the valve? Cause I noticed during disassembly that some was locked down tight as could be on the guide and others where up on the valve towards the retainer
 
nm9stheham said:
No, there 340 cast crank and 360 LA balancers, which are different. IIRC there are balanced dampers with weight kits that can be used to duplicate the 340 cast crank or 360 LA balancers.
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Yea i knew that 318/340 dampeners and 360 dampers didnt interchange. I just didnt know if 360 dampers would interchange between engines
 
dartfreak75 said:
I do have a question about the original seals are they supposed to stay locked down on the guides or do they move up and down with the valve? Cause I noticed during disassembly that some was locked down tight as could be on the guide and others where up on the valve towards the retainer
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Perfectly normal either way. Now with the Viton or the Teflon seals, they stay located on the guides.
 
toolmanmike said:
If you're building the bottom end why not just have it balanced. (you should anyway) and then everything will be neutral. (balancer, flex plate and converter.)
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The only way to get an internal balance with a stock 360 crank, and the pistons and rods he is using, is to add Mallory metal. So now you are talking $350-450-500 to get a shop to do all of that.

Never had any bottom end balanced for my rally cars or mid-performance tuff. The rally cars ran 6000 RPM regularly for the 2.6L turbo and 8k RPM over and over for the 1.9L N-A. Never broke a thing and bearing wear etc. was always good. Just stock piston & rod weights and stock crank balance.
 
dartfreak75 said:
Yea i knew that 318/340 dampeners and 360 dampers didnt interchange. I just didnt know if 360 dampers would interchange between engines
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What I am trying to say is that the 340 cast crank damper IS an imbalanced one, similar to the 360 LA but is NOT the same imbalanced one as the 360 LA. So don't get the cast crank 340 damper.
 
Looks right, but I still would not buy it or any old use damper...period. A damper works to damp out high frequency torsional vibrations in the crank, like up around 6000-8000 cycles per second. See here:
Crankshaft Torsional Absorbers, by EPI Inc.

The damper works by having a steel ring and thin rubber connecting ring that are 'tuned' to operate to absorb the vibration energy in the crank at a particular frequency range. That frequency range is where the crank would want to resonate and where the torsional vibrations could build to crank breaking level.

When the rubber gets old and hard, then the 'tuned frequency of the damper changes and it will move off of the crank's worst resonant frequency and not be as effective anymore. As the rubber gets harder and cracks, then the damper just can't damp anymore and it is useless.

So now you know what can happen if using an old damper. If it was 5 year-old damper, then OK, but any old damper might be OK or it might not (probably not). With a 'lo-po' engine, you can get away with it. But IMHO you are moving up to 'mid-po' and at least ought to get a new basic damper like a basic Pioneer model. Maybe someone has one that is a few years old that you can get on the used parts forum. Yeah, I know...it's always sumpthin'....

BTW, any imbalance in the damper to provide external balance to the crank is a separate function of the damper.
 
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