Ok I think you have the flattop pistons. Zero dish. So if you mill .025 off block you should be about .065 from top of block for piston depth. Light cleanup on head. Estimate a 58 cc head,zero dish,.065 piston below deck and .030 overbore could be about 10.25 compression any of those cams will run decent there. No need for zero deck if you have flattops .
What do you mean by light clean up on the head? Also you are saying .065 with the felpro gasket and milled .025? I'm sorry for all of this I just want to get everything right for when the time comes.
you should have a cleanup cut on head it will be minimal not enough to count on changing compression, this is just to make sure of flatness for gasket sealing purpose. if you mill just .025 off block my guess is your piston should be .065 below deck then(should verify when assembled). so just .025 off block and a flat top piston with net about 10.25 using the felpro gasket.
OK awesome. I know I was looking for something over 10. What about the cam bearings. Should I go with the dual groove? Teflon? Or stock?
dual groove should be fine. just remind installer there is a difference in installation. info should come with bearings or on ta website
My apologies for only skimming this... .065" or greater quench distance with a mild cam @ 10.25 compression in anything but a light weight, high stalled, deep-geared vehicle will be dangerously close to being a detonation maker. You will have a very difficult time tuning away from it. Wasn't it already mentioned to shoot for a .035-.045" quench distance? You won't see enough rpm's or have enough piston rock to kiss the piston to the head. When it is near the edge of detonation thresholds, the quench clearance is far more important than the static compression #. If you are spending the $$ on machining, might as well set clearances and specs more ideal.
I just found out they are the silvolite 1734. But from the pictures they have some slight valve reliefs. Does that make sense. I can provide a pic if it helps.
So at this point I want to have the block shaved so that it's only in the hole .002 equaling .045 with the felpro gasket? Dual groove cam bearing. Stick with the d5 converter? Stock pushrods or wait to custom order the length? Gasket set? Does that include everything I need minus intake and rubber ends?
D5 will work for some of the more aggressive cams. So yes depending on your choices. Full set should be all gaskets cept intake. Measure for pushrods after its assembled. If you shave block to get the quench they are talking about you need to get different pistons or you will have 13 to 1 compression and need race fuel. Dual groove would be good Get the melling oil screen and drill out pick up passage in block to 1/2 inch. I don't think milling block .080-.090 . can't be good for parts fitting
Well...sorry to disagree, but .065" quench distance is bad advice. .040-.045" is what you want, you could certainly run a bit closer...and it's to your benefit. You WANT that effect. I'd find a way to add some cc's to the chamber and piston rather than running .065". You're going to be doing that anyways. It's worth doing even with fitment issues, which you should be able to mock up now and solve. One thing that really helps is being located in MT. You can run a lot higher static compression than the guys in MN or ILL. I've gotten away with similar cammed/sized engines @ 12:1 (700 ft. elevation) by optimizing clearances and previously mentioned strategies. Am I suggesting you run 12:1? No. One of the most effective methods of preventing detonation is to get the piston to darn near hit the head. Setting your clearances now makes that a somewhat permanent solution. Temperature rise from compression at a specific crank angle prior to ignition is something you'll be fighting with a high static ratio. The other is reducing quench action or leaving "end gasses" to ignite the mix without the spark plug. That .020" difference takes you from (an assumed) 13.0 compression down to 12.3 or so. Still race gas territory unless you really know what you are doing. Got more work to do regardless. Your engine machinist should be on top of what they can get away with in your area. If they don't understand the concept of dynamic compression, ask someone else in the area that races. Here's some Googling you should do; Dynamic compression, difference with altitude, methods of octane tolerance or detonation resistance. It would be helpful for you to know your intake closing point in crankshaft degrees. Here's a useful link:http://www.wallaceracing.com/dynamic-cr.php
There is no quench area on a Buick 350, it is an open chamber design. Do not deck the block, those flat tops will give you plenty of compression without any head or block decking. The engine you bought the flat tops from was about 11.5:1 compression. Leave the piston in the hole and you will not be too high for compression.
Oops, sorry for the misdirect. I got hung up on post #40 and confused myself into thinking there were some quench chambered heads not shown. I'm still going to stand by what I wrote. There is a fantastic opportunity there IF machining isn't spared. The costs are negligible when you're already doing it. Haven't seen any heads yet that you can't machine that right off. I still say it's worth it, but not for the novice assembler though. I put pistons deck positive quite often and trim the offending portion down specifically for that purpose. Make sure and knock down the sharp edges after the machining ops. Have fun!
All your info is spot on, the only thing is there is no quench area to take advantage of with the Buick 350... Like you say it is still best to get the piston to zero deck as a practice however with his flat top pistons even without any machine work to the heads or block he will be at about 10.8:1 compression already... We are really hoping that the new TA heads have a quench area that we can take advantage of, and then then the piston position to the deck would be more of an area of improvement opportunity.
If it were my engine I would calculate the static compression, and then pick a cam that will end up with a dynamic compression that will match that. If you end up over 10.5:1 you could still make it work on pump gas premium if you get a custom camshaft ground, which is a good idea I think. The camshaft effects the compression ratio which is why there is a static and dynamic compression ratio. The static compression is physically measured by the volume of air in the piston, area between piston and head gasket, head gasket, and head chamber. The Dynamic compression ratio is the result of how the camshaft opens and closes the valves and how much of that compression is lost due to overlap. Without getting too deep into the math you can just let TA performance or a custom cam maker grind you a cam to match well with your compression ratio. If you end up under 10.5:1 the 284 cam should be a very good match, any more than that you will want a larger cam to bleed down the dynamic compression to run on pump gas. Just a FYI the guy you bought those pistons from ran a 12.00 in the quarter mile using those pistons and a custom Crower camshaft with some ported heads.
I do not think so but we need to know the other factors first before we know what your compression works out to. I have no idea the CC (volume) of the heads, or how far the pistons will sit in the hole (below deck) on your particular engine. If you have not bought a cam yet I would not be too concerned about it... Find out your compression and then go from there.
Ok. I did get the 284. But if I need to change then I will. Once I get it to the builder I'll try to get the numbers necessary to determine the best setup.
