|
Sponsored Links (Register now to hide all advertisements) |
|
|
Thread Tools | Display Modes |
11-18-2019, 09:43 PM | #1 |
Senior Member
Join Date: Sep 2011
Location: Christchurch New Zealand
Posts: 1,603
|
8ba Heads 7RT or EAB
Have an 8BA fitted to 38 PU. Doing a bit of work on it. Presently have inlet manifold off to check all valve clearances.
This PU runs well with approx 12500 mls on rebuilt engine. I did not do the work. Its presently fitted with 8RT heads C/R 6.8 :1 . I have a good set of EAB heads C/R 7.2 :1 I understand. Would there be any notticeable improvement with changing out these heads. Engine pretty much stock 40 over, Max 1cam and single 97 carb with a newly rebuilt Charlie NY chev distributor fitted with adjustable mech and adjustable vacuum advance. Not sure what present piston to head clearance is. Thanks, Phil NZ |
11-18-2019, 10:00 PM | #2 |
Senior Member
Join Date: Sep 2013
Location: SoCal-Redlands
Posts: 2,997
|
Re: 8ba Heads 7RT or EAB
I'm running EAB heads on the 8ba in my '39 p/u. Stock rebuild with a supposed Merc cam but that is it came with a bunch other other Merc parts I bought and the machinist said it was in better shape then the one that was in the engine at the time. Other than the cam(?) and EAB heads, a Bubba mechanical advance distributor, and a Charlie NY carb its 100% stock. It runs great. I think you'll notice an improvement with the EAB heads over the 8rt ones you're running now but that's JMO.
__________________
Making the simple complicated for over 30 years. |
Sponsored Links (Register now to hide all advertisements) |
|
11-18-2019, 10:04 PM | #3 |
Senior Member
Join Date: May 2010
Location: East Hartford, Ct
Posts: 5,898
|
Re: 8ba Heads 7RT or EAB
IMO it won't make that much difference unless the heads are shaved/massaged to get the much touted .050" head to piston clearance.
__________________
DON'T RECALL DOING SOMETHING FOR MYSELF BASED ON SOMEONE ELSE'S LIKES OR DISLIKES |
11-19-2019, 12:41 AM | #4 | |
Senior Member
Join Date: Sep 2011
Location: Christchurch New Zealand
Posts: 1,603
|
Re: 8ba Heads 7RT or EAB
Quote:
Or just complete valve clearance checking and keep on trucking. Phil NZ |
|
11-19-2019, 01:06 AM | #5 |
Senior Member
Join Date: May 2010
Location: MN
Posts: 7,053
|
Re: 8ba Heads 7RT or EAB
Depends on what you want to achieve. You could clay or make tin foil balls. People can get too aggressive and over mill heads. I'm a stocker with a bit of mill and lift.
Always something that when people post, I have some old heads and bolting them on. Well, but ya sure you know what condition your condition is in? Old iron heads are capable of 8:1. A good question for Ol Ron and others. . Last edited by Tinker; 11-19-2019 at 01:16 AM. |
11-19-2019, 02:21 AM | #6 |
Senior Member
Join Date: May 2010
Location: Qld, Australia
Posts: 4,195
|
Re: 8ba Heads 7RT or EAB
Sponsored Links (Register now to hide all advertisements)
I sure noticed the difference on our 33 with using heads with the larger chamber, Less MPG and torque. Lawrie |
11-19-2019, 04:35 AM | #7 |
Member Emeritus
Join Date: May 2010
Location: Fitzgerald, Georgia
Posts: 2,204
|
Re: 8ba Heads 7RT or EAB
Yes, there will be a noticeable power, efficiency, and drivability improvement if you make the proposed head swap. If you read my book you will see the actual numerical differences which I do not remember as I write this.
|
11-19-2019, 04:52 AM | #8 | |
Senior Member
Join Date: Sep 2011
Location: Christchurch New Zealand
Posts: 1,603
|
Re: 8ba Heads 7RT or EAB
Quote:
Just to recheck with the foil balls and get that 50 thou piston to head clearance. Phil NZ. |
|
Thread Tools | |
Display Modes | |
|
|
Sponsored Links (Register now to hide all advertisements) |
|