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'A 'class and 'B' class blocks.. whats the sizes?

'A 'class and 'B' class blocks.. whats the sizes?

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Discussion

TVR Beaver

Original Poster:

2,685 posts

77 months

Sunday 14th October 2012
quotequote all
I was reading last time I was away about ‘A’ class and ‘B’ class blocks but I’m buggered if I can find it now…. May have been on the V8 Forum… but does anyone know the details of this… I’m assuming it applies to TVR engines also?rolleyes

It was something like the bore dia was 94.05 / 94.08 on an A class.. and 94.08 / 94.11 on a B class?

Or was I just dreaming??
smile

Chilliman

6,002 posts

58 months

Monday 15th October 2012
quotequote all
John, you're not dreaming. The 'A' class blocks were the very best that came off the line. These were stronger than the 'B' class blocks, and were manufactured to much finer tolerances, resulting in a smoother, more powerful unit. All Chimaeras were fitted with the 'A' class block, whilst the Griff got the 'B' class block.

Hope this helps,

Chilli smile

pigpen

244 posts

147 months

Monday 15th October 2012
quotequote all
Chilliman said:
All Chimaeras were fitted with the 'A' class block, whilst the Griff got the 'B' class block.
rofl

dhf

1,103 posts

91 months

Monday 15th October 2012
quotequote all
I see trouble ahead....

Simon says

12,780 posts

118 months

Monday 15th October 2012
quotequote all
Chilliman said:
John, you're not dreaming. The 'A' class blocks were the very best that came off the line. These were stronger than the 'B' class blocks, and were manufactured to much finer tolerances, resulting in a smoother, more powerful unit. All Chimaeras were fitted with the 'A' class block, whilst the Griff got the 'B' class block.

Hope this helps,

Chilli smile
hehe

TVR Beaver

Original Poster:

2,685 posts

77 months

Monday 15th October 2012
quotequote all
tongue out

Absolutely no problem with that at all….
Let’s face it; you need some good bits in something that looks like that!

hehe

carsy

2,367 posts

62 months

Tuesday 16th October 2012
quotequote all
I believe over time the A class blocks were seen as a bit of a failure. Yes they were meant to produce a stronger faster engine but for some reason they didnt. The evidence of this i see regularly when out in the Griff and coming across one of those Chim things.

Simon says

12,780 posts

118 months

Tuesday 16th October 2012
quotequote all
carsy said:
I believe over time the A class blocks were seen as a bit of a failure. Yes they were meant to produce a stronger faster engine but for some reason they didnt. The evidence of this i see regularly when out in the Griff and coming across one of those Chim things.
Really scratchchin why are the fastest RV8 Tivs on here Chimaera's then? tongue out .... hehe You were saying ears

carsy

2,367 posts

62 months

Tuesday 16th October 2012
quotequote all
Obviously never driven a Griff then Simon. tongue out I will have to let you take mine out some time. Honestly they are a lot faster, you wont believe it. hehehehe

blitzracing

4,462 posts

117 months

Saturday 20th October 2012
quotequote all
The latter blocks (post 1997) where colour coded having been ultrasonically tested to ensure the aluminium sleeve around the liner was thick enough. Blue was the thinnest at 2.2 mm, yellow was 2.5mm and red was 2.8mm- obviously the best, and was noted by a dab of paint in the wall of the valley of the block- is this what you are thinking of?

TVR Beaver

Original Poster:

2,685 posts

77 months

Saturday 20th October 2012
quotequote all
No... I was reading it somwewhere where the liner ID had a manufacturing tolerance... and once fitted they were graded by the size of the bore?...
Was talking to Rob today.. but he's not heard of it either?.... Will have to go back in my history.. see if I can find it again .. smile

Simon says

12,780 posts

118 months

Saturday 20th October 2012
quotequote all
Simon says said:
blitzracing said:
The latter blocks (post 1997) where colour coded having been ultrasonically tested to ensure the aluminium sleeve around the liner was thick enough. Blue was the thinnest at 2.2 mm, yellow was 2.5mm and red was 2.8mm- obviously the best, and was noted by a dab of paint in the wall of the valley of the block- is this what you are thinking of?
I have a 2003 X bolter big journal block with green paint scratchchin and a tag that says factory LR exchange block redface probably liner related no doubt whistle it was cheap at the time and everything is good inc threads etc wink not sure I would use it without pressure testing at least.
Ignore the lousy valley finish/casting/flash that's all been relieved now eek




Edited by Simon says on Saturday 20th October 21:15

blitzracing

4,462 posts

117 months

Sunday 21st October 2012
quotequote all
TVR Beaver said:
No... I was reading it somwewhere where the liner ID had a manufacturing tolerance... and once fitted they were graded by the size of the bore?...
Was talking to Rob today.. but he's not heard of it either?.... Will have to go back in my history.. see if I can find it again .. smile
I do remember this being a general engine thing, specifically if re-boring the engine-worth a post on the engine forum methinks.

dhf

1,103 posts

91 months

Sunday 21st October 2012
quotequote all
I was in Power way back in Wedge time i think, and they were stripping complete engines which were rejects from LR,there were shelves of them,the guys i spoke to said take this one i'm stripping,came through without any pistons fitted....