Previous Thread
Next Thread
Print Thread
compression help 446 #3076403
09/11/22 09:05 PM
09/11/22 09:05 PM
Joined: Jan 2003
Posts: 2,623
Ca Registered: Mar-2001
H
hemiallen Offline OP
master
hemiallen  Offline OP
master
H

Joined: Jan 2003
Posts: 2,623
Ca Registered: Mar-2001
Anyone able to calculate a 446 standard stroke, Cast TRW pistons, Edelbrock heads ?

I built the engine using .060" shaved factory edelbrocks and recollection is it was calculated to be 13.3:1 with the shaved heads. Curious what it would be with stock Edelbrocks.



Thank you for any help
Allen


'05 Quad cab hemi truck- Flame red- magnaflow exhaust 70-440 cuda- 74-360-4v Challenger- new driver car EX vehicles: 66 charger Drag car- 10.80 at 123 mph 57 imperial 392 Hemi 1960 Sanger V drive- mondello-built 392 hemi
Re: compression help 446 [Re: hemiallen] #3076412
09/11/22 10:00 PM
09/11/22 10:00 PM
Joined: Dec 2021
Posts: 1,142
Loudoun County, VA
Brad_Haak Offline
super stock
Brad_Haak  Offline
super stock

Joined: Dec 2021
Posts: 1,142
Loudoun County, VA


2021 Challenger 6.4L Scat Pack 1320
100% stock: 1.680, 11.894 at 113.75 (DA 175 ft)
weight reduction, wheels, tires, Hellcat air box: 1.661, 11.686 at 115.97 (DA 710 ft)

1973 Challenger 452 ci street/strip [2008]
pump gas, DOT radials: 1.454, 10.523 at 126.44 (DA 514 ft)
Re: compression help 446 [Re: hemiallen] #3076414
09/11/22 10:05 PM
09/11/22 10:05 PM
Joined: Aug 2003
Posts: 43,215
Bend,OR USA
C
Cab_Burge Offline
I Win
Cab_Burge  Offline
I Win
C

Joined: Aug 2003
Posts: 43,215
Bend,OR USA
Which cast piston and which Edelbrock heads?
What is the size of the combustion chambers and how thick is the head gasket and the bore size on those head gasket? Last thing is how far down in the cylinders are the piston tops at TDC ?


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: compression help 446 [Re: Cab_Burge] #3076429
09/11/22 11:09 PM
09/11/22 11:09 PM
Joined: Jan 2003
Posts: 2,623
Ca Registered: Mar-2001
H
hemiallen Offline OP
master
hemiallen  Offline OP
master
H

Joined: Jan 2003
Posts: 2,623
Ca Registered: Mar-2001
The TRW's I believe are the 4 valve reliefs, they just weren't big enough for the cam. 2295's sounds right. I'm guessing the pistons are 090" below the deck as per a 440-1970.
The first version of Edelbrocks, which I believe are the small CC heads, the edelbrocks seem to be most likely 88cc, but they were the first available ones before they had optional CC chambers.
Standard Mopar steel head gaskets.


I don't know the bore x stroke, hoped an engine builder could fill in those blanks off the top of their heads. Sorry.


'05 Quad cab hemi truck- Flame red- magnaflow exhaust 70-440 cuda- 74-360-4v Challenger- new driver car EX vehicles: 66 charger Drag car- 10.80 at 123 mph 57 imperial 392 Hemi 1960 Sanger V drive- mondello-built 392 hemi
Re: compression help 446 [Re: hemiallen] #3076439
09/12/22 12:41 AM
09/12/22 12:41 AM
Joined: Aug 2003
Posts: 43,215
Bend,OR USA
C
Cab_Burge Offline
I Win
Cab_Burge  Offline
I Win
C

Joined: Aug 2003
Posts: 43,215
Bend,OR USA
Do you have a set of dial calipers? If not, can you borrow a set to measure the deck height or borrow and use a depth mike to find out exactly what the piston depth is in your motor?
As far as the heads Edelbrock has made 75.00, 84.00 and 88.0 CC BB Mopar heads in the RPM type heads. The original BB Mopar Eddy heads 88.0 CC were open chambers, the 84.0 CC had a semi close chamber combustion chamber and the 75.0 CC heads I'm not sure what they have until I look at a set of mine tomorrow, if I remember to look at them luck
On your deal it sounds like your probably near 7.5 to maybe 8.1 to 1 compression ratio based on your guess on deck heights and around an 84.0 CC head with a stock stroke and 4.350 bore size with a .022 thick head gasket with a 4.40 bore size on the head gasket diameter twocents
IHTHs luck


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: compression help 446 [Re: Cab_Burge] #3076442
09/12/22 01:06 AM
09/12/22 01:06 AM
Joined: Jan 2003
Posts: 2,623
Ca Registered: Mar-2001
H
hemiallen Offline OP
master
hemiallen  Offline OP
master
H

Joined: Jan 2003
Posts: 2,623
Ca Registered: Mar-2001
Thanks

That gives me a good idea on where I can get to.

Unfortunately it is a running engine currently and I guess my next step now that it seems I can get to pump gas, would be to pull the heads.

Thank you for the numbers.

Allen

BTW, have vacationed in Bend 4x, not sure why I thought you were more southern Oregon when I recall your move from California.

Very nice vacation place when it isn't smoked in like we have down here. Sun River is also a nice place, we stayed there when the eclipse was easily experienced about halfway between Bend and Redmond. We didn't get far north of Bend when traffic was stopped on the freeway, so we recalculated a road west of the freeway and made it several more miles north before stopping to experience it.


'05 Quad cab hemi truck- Flame red- magnaflow exhaust 70-440 cuda- 74-360-4v Challenger- new driver car EX vehicles: 66 charger Drag car- 10.80 at 123 mph 57 imperial 392 Hemi 1960 Sanger V drive- mondello-built 392 hemi






Powered by UBB.threads™ PHP Forum Software 7.7.1