440 Ideal quench

[cudarob]

Many articles on quench as gasket choice. Building a 440- 60 over with Icon FHR IC9953 pistons, rated at .015 in the hole. Have set of 906 heads with extensive porting, with a Felpro compessed to .038 would give me .053 quench, if a use the steal Mopar gasket .020 i will be at .035. Using a Mutha Thumper cam 497-483 lift cam av duration @ .50 is 235 intake and 249 exhaust lobe seperation 107degrees.
Copression should be at 10.1 any help on quench or gasket choice without milling heads will be appreciated is .035 to low is 53 too much?Piston to valve clearence should not be an issue according to Keth Black Tech. This will be a street and strip motor 80% street.

 

[Chryco Psycho]

The 906 head is an open chamber so you have to add the .100 or so in the head so with a steel gasket, you will be approx .135 clearance which =s no quench . you have to use a closed chamber head , most alum heads or the 516 / 915 iron castings to get quench ... sorry

 

[cudarob]

Any idea on horsepower with this combination with a torquer 2 open plenum dome, MSD and headers, windage tray and 750 holley HP carb

 

[Chryco Psycho]

well you should gain 20 Hp with the cam , another 20 with the headers , maybe 25 hp with the port work depending how it was done . so take 370 hp , maybe 440 gross hp range , otherwise you are stock with probably a too small carb . I suspect detonation will be a problem with this combo on pump gas though

 

[Challenger340]

With that Camshaft installed straight up(no advance) it should run fine on pump fuel(92 Octane) if your 906 heads are around 88 CC's as most are.

450hp or so ballpark, maybe more depending upon the portwork, but very close to.. or just above ..500 ft/lbs Torque.

I would not sweat the quench on the open chamber 906, not nearly as critical with the Comp "Thumpr's" or the Hughes "Whiplash" sticks, thats the trade off for the "sound".

 

[cudarob]

I am fine with that horsepower/torque should i go with the felpro.038 or the Mopar steel .016 compressed?, i do not believe valve piston clearence should be an issue with this cam but will check. .100 on intake and exhaust enough clearence.

 

[Chryco Psycho]

I would lean to using the steel shim , both will seal well & the compression change will be minimal

 

[Challenger340]

I am fine with that horsepower/torque should i go with the felpro.038 or the Mopar steel .016 compressed?, i do not believe valve piston clearence should be an issue with this cam but will check. .100 on intake and exhaust enough clearence.

IMO,
The Compression INCREASE going to the Steel Shim gasket, UP to approx 10.3:1, would be too high to remain compatible with pump gas. It amounts to another 1/2 point of Compression ratio, because the Steel Shims are approx .020" thick, or roughly .020" thinner than the .038" FelPro's.
remember here,
each .010"thickness is approx 2.4 CC's of Volume or roughly speaking (.020) "2" x 2.4 = 4.8, round off to 5 CC's of Volume.

The Compression Ratio with the FelPro Composition Gasket is around 9.8:1, which with the Iron 906 Heads @ around 88 CC's ,using that Cams events, should be fine.

The Math;
.060" over 440 is ~926 CC's swept Volume
Pistons Flycuts @ 5 CC's
FelPro gskt .038" @ ~10 CC's
Piston to Deck @ ~.010" or 2.4 CC's
906 Heads @ ~88 CC's
TOTAL Clearance Volume = 105.4 CC's
Compression ratio with the FelPro's @ 9.8:1

Compression Ratio with the Steel Shim however, would drop the clearance Volume to 100 CC's , and RAISE the Compression Ratio to 10.3:1, which IMO, is too high, and a definite "substantial" difference.

just my thoughts.

 

[cudarob]

i will stick with felpro thanks for your expertize!!!!!!