What is the differents between...

[bhardy]

a 4L hotwire from a 400se and a 4L chim/griff engine??

[tallbloke]

Early griff/chim - late wedge: Not a lot of difference.

Late Chim - early wedge: Quite a lot of difference. (Serpentine block - opposite sides for lots of stuff in the engine bay)

Why? you haven't blown it up already have you?

[Number 7]

Well "IF" you believe TVR's figures, 268 for the Wedge and 240 IIRC for the base 4L Griff/Chim. Maybe lower C.R. for the curvy cars, as I think that the 10.5:1 quoted for the Wedge was a bit marginal for a road car. Maybe a different cam, and the cats would have accounted for some of the lost power.

7.

[chassis 33]

Only the press cars ever pumped out 240bhp, most well sorted Chims in standard spec pump out about 200 to 210 from the 4litre. IIRC the Chim 4litre runs at 9.75:1 CR

Regards
Iain

[JR]

Number 7 said:

Maybe a different cam, and the cats would have accounted for some of the lost power.

Yes, wilder cam for the wedge, probably combined with wilder power claim as well.

[wedg1e]

I believe only the 390SE engine ran 10.5:1 cr, most 'standard' 4L engines (3948cc) were 9.75:1... or even 9.35:1

[Number 7]

JR said:

probably combined with wilder power claim as well.

Interestingly, Robsons book quotes 10.5:1 for the 400, but only 9.75:1 for the 450.

7.

[chassis 33]

wedg1e said:

I believe only the 390SE engine ran 10.5:1 cr, most 'standard' 4L engines (3948cc) were 9.75:1... or even 9.35:1

9.35 is the standard SD1 EFi spec

Regards
Iain

[bhardy]

tallbloke said:

Why? you haven't blown it up already have you?

just reading as much as i can about the 400, getting to know her details as the 400 is quite different to my 'old' 350i...