Carb and EFI block differences

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Eff1 Shifty
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Carb and EFI block differences

Post #1 by Eff1 Shifty » Mon Jan 18, 2016 10:54 am

Just picked up an old carburated motor for 50$. I did this hoping I could use the block for my EFI rebuild. I couldnt find any information about differences in block designs. Will I be able to use the efi serpentine setup on the old block? Same bearings and gaskets? If anyone knows for sure, let me know... 

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bubba22349
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Re: Carb and EFI block differences

Post #2 by bubba22349 » Mon Jan 18, 2016 11:18 am

:hmmm: There are very few differences between a Carb and EFI block. First off the EFI blocks don't have the hole cut out for the old mechanical fuel pumps so you can make or buy a simple cover plate to fix that. Next is that the location of the Dipstick tube is different too you will need to solve that problem and drill and tap the block to adapt the tube from the EFI block. As far as I know the serpentine drive belt system will bolt right on too. Good luck :nod:
A bad day Drag Racing is still better than a good day at work!

I am still hunting for a project car to build but with my current low budget it's not looking so good. My Ex- Fleet of Sixes these are all long gone! :bang: 1954 Customline 223 3 speed with O/D, 1963 Fairlane project drag car with BB6, 1977 Maverick 250 with C4, 1994 F-150 a 300 with 5 speed.

Eff1 Shifty
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Re: Carb and EFI block differences

Post #3 by Eff1 Shifty » Mon Jan 18, 2016 1:47 pm

Good to know about the dipstick. :nod: I guess ill build the old block. Assuming its not junk :P

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bubba22349
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Re: Carb and EFI block differences

Post #4 by bubba22349 » Mon Jan 18, 2016 2:18 pm

I don't think it's impossible to install the EFI dipstick in an early block if you had the right measurements off the later block, mine was a 94 F150 2 wheel drive truck, you didn't mention what yours was but the 4x4's could also use a little different oil pan and or dipstick. Another way would be to mod and weld the tube into the oil pan in the right spot. Main and Rod Bearings are the same, cam timing gear is Fiber on EFI but you can change over to the early style steel or combo Alum and steel, the late 1995's to 97 300's / 4.9 had the best / stronger pistons (hyperectic), on the gaskets and seals if you use an EFI head and fuel injection unit then all the top end gaskets will work. The bottom end gaskets of the EFI engines (pan gasket) can also be used and is much better than those they used on the old carb engines, the EFI rear main seal (is one piece design) it could be different then some of the early carb engines but that all depends on year Casting of your block and in that case you can just use a two piece neoprene seal clocked a 1/4 inch from the blocks parting line. One other possible difference is that Ford used two different piston pin sizes so the Conecting Rods on the real early engines 1965 up to 1968 were .912 pin size after 1968 all 300's used Rods with a .975 piston pin size. Good luck :nod:
A bad day Drag Racing is still better than a good day at work!

I am still hunting for a project car to build but with my current low budget it's not looking so good. My Ex- Fleet of Sixes these are all long gone! :bang: 1954 Customline 223 3 speed with O/D, 1963 Fairlane project drag car with BB6, 1977 Maverick 250 with C4, 1994 F-150 a 300 with 5 speed.

Eff1 Shifty
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Re: Carb and EFI block differences

Post #5 by Eff1 Shifty » Mon Jan 18, 2016 9:47 pm

Im definitely hoping for a one piece rear main seal. Ill probably have the machine shop deal with the dipstick once i figure out where the efi one goes. I do plan on going with the 96 pistons and rods like you mentioned, and gasket set. Ill keep the thread updated.

Fordman75
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Re: Carb and EFI block differences

Post #6 by Fordman75 » Tue Jan 19, 2016 5:34 pm

All 240/300's have a one piece rear main seal.

I might be wrong but I believe the EFI blocks have a boss for a knock sensor to screw into. The carb blocks won't have that.
Ted

54 Ford F100/F150 4x4
300, NP435 4spd, NP205 transfercase

Eff1 Shifty
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Re: Carb and EFI block differences

Post #7 by Eff1 Shifty » Tue Jan 19, 2016 7:50 pm

Well that might be a deal breaker. Ill check that out tomorrow.

Eff1 Shifty
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Re: Carb and EFI block differences

Post #8 by Eff1 Shifty » Tue Jan 19, 2016 8:20 pm

Unfortunately I think youre right about not having a place for a knock sensor. I just took a quick look and I didnt see a place for one next to the distributor. Ill look better later but for now it seems youre right. I guess an old carb'd block might not be a good start to an efi build

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