EFI head on carbed engine
Thread Starter
|
Freshman User
Joined: Apr 2011
Posts: 44
Likes: 0
EFI head on carbed engine
I was wondering if an EFI head will swap easily with my carbed head. I was at the junk yard to get some EFI ex manifolds and the could not resist the getting the head as well.
Postmaster
Joined: Dec 2006
Posts: 3,603
Likes: 10
From: Spokane, WA
FORDSIX PERFORMANCE • Login
That thread is about porting. It's written for the SB6 but the principles are the same for the BB6.
That thread is about porting. It's written for the SB6 but the principles are the same for the BB6.
Postmaster
Joined: Mar 2005
Posts: 2,949
Likes: 6
From: Earth
The conventional wisdom on EFI heads is not to cut them for larger valves. They would be shrouded even worse and deshrouding ruins the fast burn. Porting will still help. Polishing usually refers to the combustion chamber; I'm pretty ambivalent on the benefits once you get past cleaning up ridges or casting flash that could turn into a hotspot. It's going to be covered in carbon soon enough anyway...
Postmaster
Joined: Dec 2006
Posts: 3,603
Likes: 10
From: Spokane, WA
Trending Topics
Posting Guru
Joined: Jun 2004
Posts: 1,092
Likes: 2
From: Casa Grande
I'd suggest you register over there. Good site and some good people. Wouldn't say they are anymore knowledgeable than people here but sometime a different point of view.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 6 Best Deals Available on New Fords & Lincolns Right Now
Brett Foote
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Verdad Gallardo
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Elder User
Joined: Nov 2004
Posts: 666
Likes: 5
Just a couple of points.
The EFI heads are more prone to cracking than the carb heads. Make sure you have it magnafluxed before you use it. If you do any porting, be very conservative, they are thin wall castings.
If they have a different style rocker arm, make sure your valve train is properly set with the new head. I don't recall all of the flavors, but some rockers are adjustable, some are not. Just make sure you get the right amount of compression on the lifter piston.
The EFI heads are more prone to cracking than the carb heads. Make sure you have it magnafluxed before you use it. If you do any porting, be very conservative, they are thin wall castings.
If they have a different style rocker arm, make sure your valve train is properly set with the new head. I don't recall all of the flavors, but some rockers are adjustable, some are not. Just make sure you get the right amount of compression on the lifter piston.
Moderator
Joined: Dec 2007
Posts: 7,987
Likes: 104
From: Boise, Idaho
I think a magnaflux is around $35 or so. Call around to a few shops and see what they charge.
Also have them check to see if it's flat. If it's warped, you'll need to have it planed, which I think is around $80.
Also have them check to see if it's flat. If it's warped, you'll need to have it planed, which I think is around $80.
Thread Starter
|
Freshman User
Joined: Apr 2011
Posts: 44
Likes: 0
Luckily I live in the racing capital of the USA, Charlotte NC. Magnaflux cost me 5 bucks. The guy raced straight sixes for 40 years. Between the great people on this site and him, I can't go wrong.
So, porting and polishing... Do I need to use carbide bits? Or can somebody recommend, the best, kit of bits to get? (best= cheapest to get the job done properly).
Then match to mr. gasket #260.
Then use that size all the way back?
So, porting and polishing... Do I need to use carbide bits? Or can somebody recommend, the best, kit of bits to get? (best= cheapest to get the job done properly).
Then match to mr. gasket #260.
Then use that size all the way back?
Postmaster
Joined: Mar 2005
Posts: 2,949
Likes: 6
From: Earth
I've got to know. Now, I would tell anyone to get their head(s) and block checked for cracks before starting in on any machine work, but every time someone mentions "EFI head" folks start chiming in on how they're more prone to crack that carb heads.
Is this just conventional wisdom or has someone actually compiled data on head cracking in 300s? Where are they more prone to crack? And why? They're made by the same company in the same factory as the carbed heads before them, right? So what is it about EFI heads that makes them more likely to crack? The two extra bolt holes tapped for the exhaust manifolds? My carbed '86 has the EFI manifold bolt pattern for the intake/exhaust manifolds. Should I be worried about cracking?
I'm not saying EFI heads aren't more likely to be cracked, but where does this particular factoid come from?
Is this just conventional wisdom or has someone actually compiled data on head cracking in 300s? Where are they more prone to crack? And why? They're made by the same company in the same factory as the carbed heads before them, right? So what is it about EFI heads that makes them more likely to crack? The two extra bolt holes tapped for the exhaust manifolds? My carbed '86 has the EFI manifold bolt pattern for the intake/exhaust manifolds. Should I be worried about cracking?
I'm not saying EFI heads aren't more likely to be cracked, but where does this particular factoid come from?