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eastw77

v8 suspect liners

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Hi, I recently accuired a P76 V8 of unknown history. I have stripped the engine down and I have found it to be in poor condition with heavy scoring on the piston skirts, cam wear, a very slack timing chain and wear on the crank. My main worry though is at least 4 of the liners are not in line with the deck height and I am worried they have slipped. A picture say a 1000 words so here goes..

No.8 cyl main worry is bad area at approx 10 o'clock.

F1525C5C-71B3-4D2B-9288-345F2BAA11FE_zps

No. 1 cyl similar.

9C443AC7-2679-4EE8-B5A0-EB27DC0B288A_zps

No. 4 liner sitting proud.

DB1C9503-5A92-416E-8027-2FB8787960ED_zps

No. 3 liner recessed.

C075CFA5-C98B-4F0D-95D1-81F1FAADA604_zps

What do you guys think? Is this block worth bothering with?

I also have a 3.9 rover stripped in the shed with a good block but the crank is toast. Is it possible to fit the p76 crank to the 3.9 block i.e grind the main brgs down to rover size or line bore to P76 size, which wold be the best option? Does anyone know of any rods which would be suitable

if I used the 3.9 Pistons with the P76 crank?

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Hi, I recently accuired a P76 V8 of unknown history. I have stripped the engine down and I have found it to be in poor condition with heavy scoring on the piston skirts, cam wear, a very slack timing chain and wear on the crank. My main worry though is at least 4 of the liners are not in line with the deck height and I am worried they have slipped. A picture say a 1000 words so here goes..

No.8 cyl main worry is bad area at approx 10 o'clock.

F1525C5C-71B3-4D2B-9288-345F2BAA11FE_zps

No. 1 cyl similar.

9C443AC7-2679-4EE8-B5A0-EB27DC0B288A_zps

No. 4 liner sitting proud.

DB1C9503-5A92-416E-8027-2FB8787960ED_zps

No. 3 liner recessed.

C075CFA5-C98B-4F0D-95D1-81F1FAADA604_zps

What do you guys think? Is this block worth bothering with?

I also have a 3.9 rover stripped in the shed with a good block but the crank is toast. Is it possible to fit the p76 crank to the 3.9 block i.e grind the main brgs down to rover size or line bore to P76 size, which wold be the best option? Does anyone know of any rods which would be suitable

if I used the 3.9 Pistons with the P76 crank?

You would probably be looking at rods and pistons to get it to work, it looks like they have been done by both methods (grinding or line boring). There is a guy in Christchurch that made a new long stroke crank and pistons to fit in the 3.5 block to take it out to around 4.5. If you do find a good piston/rod combo post it up

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The 4.4 P76 engine is not a good engine and cannot handle revs - I would ditch it and get a RV8. Google the P76 engine on AULRO and other forums and you will see the issues.

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You might have more luck by talking to a engine builder who has been around for a while, chances are there were a lot of these sort of conversions done in the 80s and it seems nothing from the 80s made it onto the net. I dont know who is up your way but Im sure someone like Gavin Hill in Chch could give a run down on options and viability of doing this

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Thanks guys, yes I think I will be looking at new rods and Pistons. I have a few names of guys to contact for advice. I will post up what I end up finding out.

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The block is essentially a 3.5, and has a mega stroked crank to take it to 4.4.

3.5- 88.9mm bore 71mm stroke

A 3.9 uses the same crank as a 3.5, just 94mm bore.

P76 4.4- 88.9mm bore 88.9mm stroke

I think you could build a bigger beast by using the crank and rods from the P76 in the 3.9 block, I'm not 100% sure but if the gudgeon pin is at the same height from the crown it could all go together....

3.9 94mm bore and 88.9mm p76 crank would make 4931cc :D

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Might be worth measuring the block deck height as well, I've been googling but I can't find the info.... From pictures it looks a bit different.

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I am sure the block height is different on a P76, to fit RV8 inlets for example you use spacers between the manifold and head.

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Yes the P76 block is around 17mm higher.... so you need a piston rod combo with a compression height that is about 17mm less than the rover setup. This is possible, the engine in mine has the longer stroke crank and custom pistons with RV8 rods in a 3.5l block. I was having a look at the ACL site this morning and it might be possible to use a Ford cross flow piston if they are available in a big enough oversize.

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