BOA Block V BOB Block

Problems with your Mk3 Granada

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dave73
Posts: 33
Joined: Mon Oct 05, 2015 11:23 pm

BOA Block V BOB Block

Post by dave73 »

As BOA engines become rare, if the blocks had it can we use a BOB block, are they the same, will all the ancillaries fit it including heads.

thanks Dave
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Garry Bottomley
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Re: BOA Block V BOB Block

Post by Garry Bottomley »

Going by this Ford publication would say no . Especially with regard to cam drive chains .

V6 24V Cosworth Engine

The revised V6 24V Cosworth engine for the Scorpio ’95 has the engine code BOB.
It has the following new or modified components

Modified intake system with carry-over throttle housing.
Camshaft drive with two simplex chains instead of one duplex chain.
Modified cylinder block with modified front cover to match the new camshaft drive.
Both cylinder heads have been shortened at the rear end for reasons of space.
Modified sump with new oi1 dipstick and tube.
Repositioned oil filter.
Repositioned thermostat housing.
New exhaust manifolds with new gaskets and heat shields.
New extended EEC engine management system with sequential multipoint fuel injection
(SFI).
New double fuel rail with new (twin spray) injectors.
New platinum spark plugs, modified HT leads and repositioned ignition coil.
New improved HO2S sensors mounted on the exhaust manifolds.
New VIS solenoid-operated vacuum valve.
New fuel system line routing.
New cooling fans.
Modified radiator.
New drive belts for auxiliaries.
New valves and lines for the evaporative emission control system.
dave73
Posts: 33
Joined: Mon Oct 05, 2015 11:23 pm

Re: BOA Block V BOB Block

Post by dave73 »

Thank you Gary

Very detailed reply, i like it. Need to get my viscous fan off, whats the best way?

Dave
dave73
Posts: 33
Joined: Mon Oct 05, 2015 11:23 pm

Re: BOA Block V BOB Block

Post by dave73 »

Its ok Gary, its off,

had to make up 36mm cranked spanner and rotate clockwise for anybody else who reads this. Its a left hand thread, held the water pump pulley with a nylon/fabric strap.

Cheers David
mk2 cossie
Posts: 40
Joined: Sat Feb 16, 2013 3:37 pm

Re: BOA Block V BOB Block

Post by mk2 cossie »

The block itself, yes.
There is apparently an oil way blocked off in a different spot behind the timing cover.
Otherwise, the heads and timing gear of the BOA can be used on a BOB block.
Not sure if the crankshaft nose is the same for the timing chain, but the BOB block has stronger webbing cast in for the main bearing caps
dave73
Posts: 33
Joined: Mon Oct 05, 2015 11:23 pm

Re: BOA Block V BOB Block

Post by dave73 »

M2 Cossie, are you saying you've done this, can you clear the blocked oilway on the BOB block?

"The block itself, yes.
There is apparently an oil way blocked off in a different spot behind the timing cover.
Otherwise, the heads and timing gear of the BOA can be used on a BOB block.
Not sure if the crankshaft nose is the same for the timing chain, but the BOB block has stronger webbing cast in for the main bearing caps"

thanks Dave
mk2 cossie
Posts: 40
Joined: Sat Feb 16, 2013 3:37 pm

Re: BOA Block V BOB Block

Post by mk2 cossie »

dave73 wrote: Tue Sep 05, 2023 3:37 pm M2 Cossie, are you saying you've done this, can you clear the blocked oilway on the BOB block?

"The block itself, yes.
There is apparently an oil way blocked off in a different spot behind the timing cover.
Otherwise, the heads and timing gear of the BOA can be used on a BOB block.
Not sure if the crankshaft nose is the same for the timing chain, but the BOB block has stronger webbing cast in for the main bearing caps"

thanks Dave
Not myself, no.
Only have 1 full strip down and rebuild under my belt, and that is the BOA that is in my mk2 Granada..

There are many people on the fordpower forum that have done so, and I think possibly Top Boss tuning as well.
The BOB has thicker castings for the bearing caps in the block, and is more desirable for forced induction engine swaps.
The oil way l, as far as I know, is a choice of drilling. And either one is blocked depending on the front cover. (I don't know for certain, as never needed to know)
CosworthBob53
Posts: 231
Joined: Sat Feb 16, 2013 4:36 pm
Location: Northampton

Re: BOA Block V BOB Block

Post by CosworthBob53 »

The best person to contact for information on both BOA and BOB engines is Mike at Boost Performance who is a regular contributor on fordpower. He is regularly rebuilding the engines for people including undertaking twin turbo conversions and knows both engines inside and out.

Bob
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