What I have 505 short block flat top pistons 0 deck . Looking for street driving options. I have a holley sniper and complete in tank fuel system, holley hyper spark ignition, TTI 2" header and 3" exhaust, 9 1/2" converter. Looking for suggestions on HEAD and Cam options. Do not want racing anything. ????
505 short block
- Thread starter EARLY B
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rumblefish360
Well-Known Member
What car?
What’s the cars weight, rear gear ratio and tire size?
Do you have power brakes?
Is vacuum important?
The over all goal is?
What’s the cars weight, rear gear ratio and tire size?
Do you have power brakes?
Is vacuum important?
The over all goal is?
BSB67
Well-Known Member
Your challenge will be the heads/compression ratio. Measure how far down your pistons are. If you want a decent quench, you’ll need a 88 to 90 cc head for pump gas. If you talk to MCH, they can target that cc range as part of their CNC porting.
Otherwise. Just purchase the larger (80+) cc heads and gasket up accordingly.
Otherwise. Just purchase the larger (80+) cc heads and gasket up accordingly.
Even with a 88 cc head your still at 11-1 C/R.... And 88 cc heads are open chamber so no quench with flat top piston.....
Honestly the better option is tear it down now & swap the pistons... Anything else is a patch....
@Kern Dog
, TTI 2" header and 3" exhaust, 9 1/2" converter. Looking for suggestions on HEAD and Cam options. Do not want racing anything. ????
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A patch, a crutch...call it what you like. There is a right way then there are ways that sort of work.
I had flat top pistons .012 in the hole and with the milled Edelbrock heads measuring at 82 ccs and a standard .039 Fel Pro head gasket, I was almost to 11 to 1 compression. My crutch was to use .075 Cometic head gaskets to drop the ratio to around 10.2. It killed quench but didn't knock anymore.
I rebuilt the engine using dished/stepped pistons that lowered the compression ratio to 9.8 but with quench. It runs strong on 91 octane and does not knock.
I had flat top pistons .012 in the hole and with the milled Edelbrock heads measuring at 82 ccs and a standard .039 Fel Pro head gasket, I was almost to 11 to 1 compression. My crutch was to use .075 Cometic head gaskets to drop the ratio to around 10.2. It killed quench but didn't knock anymore.
I rebuilt the engine using dished/stepped pistons that lowered the compression ratio to 9.8 but with quench. It runs strong on 91 octane and does not knock.
BSB67
Well-Known Member
When MCH CNC ports the 84 cc head the combustion chamber comes out to 88 due to the material removed around the valves. Tell them you want 90, and they’ll do it, and you’ll retain the quench. It will be 10.8:1, and work fine with a medium size cam in PA on pump premium.
1966 CORONET STOCK BODY 355 REAR NO POWER BRAKES. GOAL IS START CAR AND DRIVE.
NEW PISTONS $650.00 PLUS REBALANCE $$$
rumblefish360
Well-Known Member
For Sale, pistons, used for mock up, never ran.... $350...
Balance, yeah, a few $$ but which ever direction you choose is gonna cost, Which way is gonna give the most dependable streetable result...
Runcharger
Well-Known Member
Do the pistons have valve reliefs in them?
What about 346 or 452s with the fat felpro gasket.
Thank You.. Well Said..
It's not about the money !!!! It,s about using all the junk I have collected for 50years! Was just looking for ideas to make this work.
But the other point is making it work well.... For it's intended purpose.... The pistons you have are great if your looking to build an engine that wants a little AV gas in every tankful of premium...
Like I posted earlier
TTI 2" header and 3" exhaust, 9 1/2" converter. Looking for suggestions on HEAD and Cam options. Do not want racing anything. ????
In particular the " Do not want racing anything." line... Well you can get away with the bigger headers & bigger exhaust, ever the loose convertor without to much of a penalty... But If you put it on the road & need to add race fuel every time you take it out it won't get used much... I know wayyyy to many guys that have done that....
I organize cruises around my area, we drive anywhere from 100 miles to 400 miles on these cruises.. I haven't driven less than 2000 miles on my old cars per year in at least fifteen years.. Mu friends who've built an engine with to much compression? I can't think of one who's done a thousand miles in a single year, never mind about two years in a row....
It looks like a 84cc head and a 0.060 4.5 bore gasket. now on to the cam
Anyone have a suggestion for a street cam for this motor?
Looking like a Howards hyd roller part # HRCCL 720555-12
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