Previous Thread
Next Thread
Print Thread
Eagle heads on a hellcat short block #2334378
07/09/17 10:50 PM
07/09/17 10:50 PM
Joined: Aug 2003
Posts: 3,245
Between a rock & a hard place
C
cudadoug Offline OP
master
cudadoug  Offline OP
master
C

Joined: Aug 2003
Posts: 3,245
Between a rock & a hard place
I'm considering a hellcat crate shortblock for my gen 3 swap project to use with Eagle heads. My question is has anyone done this and the resulting piston to valve clearance?

I am being told that the Eagle heads on a 9:1 OE 5.7 will bump that to 11:1, but the piston to valve clearance will disappear.

Would the same be true for the hellcat shortblock??

Thanks in advance for your input!

Last edited by cudadoug; 07/09/17 10:51 PM.
Re: Eagle heads on a hellcat short block [Re: cudadoug] #2334381
07/09/17 10:59 PM
07/09/17 10:59 PM
Joined: Feb 2011
Posts: 4,302
Nebraska
72Swinger Offline
master
72Swinger  Offline
master

Joined: Feb 2011
Posts: 4,302
Nebraska
Im not sure on Hellcat piston. I think the valve position between an Apache/Hellcat head and an Eagle are identical. The Eagle has a smaller valve diameter than a Hellcat so you might actually gain piston to valve clearance. Like any engine build worth its salt, clay it anyway. Compression wise I dont think you would get much over 10.1 though since chamber cc isnt to much less than a Hellcat head.


Mopar to the bone!!!
Re: Eagle heads on a hellcat short block [Re: cudadoug] #2334424
07/10/17 12:07 AM
07/10/17 12:07 AM
Joined: Aug 2003
Posts: 3,245
Between a rock & a hard place
C
cudadoug Offline OP
master
cudadoug  Offline OP
master
C

Joined: Aug 2003
Posts: 3,245
Between a rock & a hard place
Interesting. I wasn't aware of the hellcat head cc.

Last edited by cudadoug; 07/10/17 12:07 AM.
Re: Eagle heads on a hellcat short block [Re: cudadoug] #2334943
07/10/17 09:28 PM
07/10/17 09:28 PM
Joined: Jun 2016
Posts: 170
Wisconsin
M
Medlock51 Offline
member
Medlock51  Offline
member
M

Joined: Jun 2016
Posts: 170
Wisconsin
Like a real Hemi chamber these newer designs can take a one point higher compression number than a wedge head can handle.

Re: Eagle heads on a hellcat short block [Re: cudadoug] #2335030
07/10/17 11:20 PM
07/10/17 11:20 PM
Joined: Oct 2006
Posts: 4,590
Indy
J
joshking440 Offline
Lunch is on me!
joshking440  Offline
Lunch is on me!
J

Joined: Oct 2006
Posts: 4,590
Indy
What do you mean? That the larger chamber allows higher compression under boost?

Re: Eagle heads on a hellcat short block [Re: cudadoug] #2335069
07/11/17 12:10 AM
07/11/17 12:10 AM
Joined: Feb 2011
Posts: 4,302
Nebraska
72Swinger Offline
master
72Swinger  Offline
master

Joined: Feb 2011
Posts: 4,302
Nebraska
Hellcat has 9.5.1 Compression with IIRC a 70cc chamber, pretty sure the Hellcat head is same as Apache chamber wise. Eagle heads are 65cc chamber, so technically you're only reducing chamber volume 5cc instead of 20cc on an early 5.7 swap.


Mopar to the bone!!!
Re: Eagle heads on a hellcat short block [Re: joshking440] #2335596
07/11/17 11:08 PM
07/11/17 11:08 PM
Joined: Jun 2016
Posts: 170
Wisconsin
M
Medlock51 Offline
member
Medlock51  Offline
member
M

Joined: Jun 2016
Posts: 170
Wisconsin
No... the Hemi design eliminates much of the detonation that comes with a wedge design with sharp edges in the chamber and less than ideal flame travel.

Re: Eagle heads on a hellcat short block [Re: Medlock51] #2337043
07/14/17 07:54 PM
07/14/17 07:54 PM
Joined: Jan 2003
Posts: 16,376
D
dogdays Offline
I Live Here
dogdays  Offline
I Live Here
D

Joined: Jan 2003
Posts: 16,376
Keep telling yourself that.....

R.

Re: Eagle heads on a hellcat short block [Re: dogdays] #2337170
07/15/17 12:39 AM
07/15/17 12:39 AM
Joined: Jun 2016
Posts: 170
Wisconsin
M
Medlock51 Offline
member
Medlock51  Offline
member
M

Joined: Jun 2016
Posts: 170
Wisconsin
Originally Posted By dogdays
Keep telling yourself that.....

R.


I will... before I built my last blown early Hemi I talked to many of the best builders n the biz... everyone told me the same thing. If Gartlis tells me something about a Hemi I tend to agree...

Re: Eagle heads on a hellcat short block [Re: cudadoug] #2337303
07/15/17 12:06 PM
07/15/17 12:06 PM
Joined: Sep 2007
Posts: 14,889
up yours
Supercuda Offline
About to go away
Supercuda  Offline
About to go away

Joined: Sep 2007
Posts: 14,889
up yours
Compare combustion chambers before you extrapolate early hemi info to a Gen III. Not even the same. May as well used SBC thinking as it's just as relevant.


They say there are no such thing as a stupid question.
They say there is always the exception that proves the rule.
Don't be the exception.
Re: Eagle heads on a hellcat short block [Re: cudadoug] #2337462
07/15/17 05:42 PM
07/15/17 05:42 PM
Joined: Jan 2008
Posts: 4,254
Canada
WO23Coronet Offline
master
WO23Coronet  Offline
master

Joined: Jan 2008
Posts: 4,254
Canada
They new Hemi chambers seem pretty efficient, they don't need much ignition timing for max power

Re: Eagle heads on a hellcat short block [Re: cudadoug] #2341019
07/21/17 04:14 PM
07/21/17 04:14 PM
Joined: Jan 2003
Posts: 9,963
Frostbitefalls MN (Rocky&Bullw...
gregsdart Offline
master
gregsdart  Offline
master

Joined: Jan 2003
Posts: 9,963
Frostbitefalls MN (Rocky&Bullw...
The new Hemis are detonation resistant due to charge motion, like quench creates. That and dual plugs.

Last edited by gregsdart; 07/21/17 04:14 PM.

8..603 156 mph best, 2905 lbs 549, indy 572-13, alky






Powered by UBB.threads™ PHP Forum Software 7.7.1