Thread: Engine Assembly Question

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Man I'm gonna be hanging it out here for a few folks to give it a free kick but here it goes. (Easy on me Pat) Got the .040" + 350 4 bolt on the stand cleaned and painted. Did the preassembly and got a .030" deck height with recon rods(w/arps) and H345NP Speedpro pistons 10:2-1@ 64cc. My gasket set on the bench is th FelPro KS2600 with a uncompressed .048" headgasket.
My heads are 462's, 61 cc with 2.02's,.550" springs, 1.6 rollers. The cam is a comp cams 280H. I know I need a .035"-.040" quench. I believe I need .100" clearance on the intake valve/.080" on the exhaust for piston to valve clearance. For my quench, if I sit .030" down in the block, I will need at most a .015" head gasket, correct??? Then If I understand this right @1.6 my .480 lift will be 510". If my intake is gonna open .510" and I'm already tight with a .015" gasket, how is this gonna work. How do you get the "happy" between the v/p clearance and a correct squish????? I have to order my light springs to check the vp myself, but should I be anticipating problems here or am I JUST FREAKING OUT because of ignorance (been known to do that). Anyway HELP!! I'm just missing something obviously. OK Tech, Eric, Dave, have at me.

Oh No!! You were one I was dreading getting a butt scolding from too!

yep some times you can not have every thing .first make a list from 1to8 for the intake Pv and the ex 1-8 and just see how muchPV room you have across the boad and then see if you need to cut the valve notch deeper if you say you .030 down deck that off the block fly cut pistons by 030 and your be where you were. check first with test springs the valves may not be seting in the heads it the same depth. same is true for the deck and square and the rods all at the same length then you can equal out the valves get the deck even then you have less to worry about or cut each piston for need vp for the hole it came out of when i do a valve job i check my 45 to the head deck. i deck the block with the BHJ tru deck this helps alot alot less chances of finding no vp on one hole .have seen it happen. when square you may find no vp at all this happens to

Its amazing how someone, somewhere, will actually put this same combo together tomorrow without checking clearances and then wonder why it ate itself. Nice having the advice handy to get it right. Thanks. All input welcome 24-7.

The head gasket supplied in the kit is 7733PT2, a composition perma-torque design. Here's the skinny on it....
http://store.summitracing.com/egnsea...nresults=false
It's good to 10.5 scr or less and 420 hp or less and displaces 8.54 cc's @ 0.039" compressed. I would do one of two things here, either cut the decks for a better squish with the 7733PT2 (zero deck will put the squish at 0.039") or use a much thinner gasket such as the Fel-Pro 1094 for a squish of 0.045".
http://store.summitracing.com/partde...4&autoview=sku
The pistons you have chosen have 4 valve reliefs and a total volume in the eyebrows of 5.0 cc's....
http://store.summitracing.com/partde...art=STL-H345NP
You have 6.3 cc's in the deck.
Assuming you go with the thinner gasket and leave the deck alone (that's what I would do), your scr would be as follows....
Volume inducted would be 731 in the cylinder, 61 in the chamber, 3.2 in the gasket, 6.3 in the deck and 5.0 in the piston. Total...806.5
Volume compressed would be 61, 3.2, 6.3 and 5.0....Total 75.5
806.5 divided by 75.5 reveals 10.68:1 scr.

I think that all will agree that it is better to build a little more compression into the motor with a tight squish than a little less compression with a loose squish and then choose a cam that will allow the motor to run on pump gas.
I might choose a hydraulic roller something like this....(I'm done with flat tappets)....
http://www.cranecams.com/?show=brows...tType=camshaft
I'd use the springs recommended by the cam grinder to go with this cam along with 1.5 rockers and a short rear gear with a 3K converter.

If you don't like what you see in this post, use a different piston or different heads and back down on the scr.

Richard thats simply awesome. Thank you very much. I appreciate the effort and have all the info I need now. Thanks guys.