Wanted: 4.50 litre cylinder heads

[JRA400]

Are there any out there for sale?

Cheers

JRA400

[Chuffmeister]

Aren't they the same as the 4.0l heads on a standard 4.6?

[macdeb]

no, bigger valves iirc.

[db484bhpv8]

Pretty sure most 450 heads are the biggest valves same as 500's but not ported as extensively.

[Chuffmeister]

Dunno, sat in Cafe Nero in London waiting for my daughter to come out of the ballet, so haven't got the SH bible to hand! I thought that the only other BV heads other than the 500's were on a few special 4.3's? Either way, there was a pair of 500 heads on Ebay the other day...

[OleVix]

450 heads are std 4.6 rover, ie same as 4.0 and 3.9 exept double valvesprings

[Goaty Bill 2]

db484bhpv8 said:

... same as 500's but not ported as extensively.

They barely scratched the ports on my heads at TVR when they built it. (yes, I mean from new).
I could have done as much good with 5 minutes and a ladies nail file from Boots.

At least they did actually fit the large valves. Albeit they were left fully shrouded in the chambers, with no opening up of the throat below. All in all, they probably flowed almost as well as a set of stocker 400 heads.

[italian job]

What are standard valve sizes? My 450 heads were recently stripped by Rob at V8 developments,he said they were big valve heads,they have double valve springs. Valve sizes were 42/37.

[db484bhpv8]

See the difference. My 500 heads.

[italian job]

Definitely see the difference in porting,dont think my heads have been ported at all,how do the valve sizes compare?

[db484bhpv8]

italian job said:

Definitely see the difference in porting,dont think my heads have been ported at all,how do the valve sizes compare?

IIRC mine were same as yours.