The V8 Owners Forum -

been offered some TVR heads, believe they are 28cc but not sure on this yet, they are 14stud.

my engines a 10 stud 3.9 from a classic rangy, i intend to fit a fastish cam, probly a crower 233 i think.

do the TVR heads differ much? how soutable for my engine are they? and what sort of power are they capable of flowing?

are they just ported or did they put bigger valves in? or do i need more info from seller?


Ralph

Ralph,

14 Bolt heads are usually 36cc. chambers so you would lose quite a bit of compression unless these heads have been heavily skimmed, do you know what TVR engine these heads are off and what gaskets are you using?

3.9 blocks are normally 14 bolt unless it's an intermediate block with provision for cross bolting.

Re the cam, personally for a road engine with modded heads I wouldn't use more than a Crower 50232, V8 Tuner usually has them on special offer for approx £130.00 use with Hi- Rev lifters to allow 6000 RPM.

Kevin.

whats best way of telling how many cc they are? will the numbers off them tell or is it a case of actually measuring them? will try an find out what car they where from.

i think mine is probably intermediate then, only 10 bolt, it has the little round blocks where the cross bolts would be but they are nto drilled out, it was a Morgan plus 8 engine. is it still ok to bolt on 14 stud heads? or am i best off getting heads suited for my engine?

im not made up on which cam yet, if i buy these heads it will delay buying the cam anyway.


Ralph


edit, im not sure which gaskets yet as havent built a V8 yet, but i presume its best to use the composite ones?

Get the seller to measure the valve sizes and the height and width of the inlet and exhaust ports - this will give you half an indication of the work on the heads.

Andrew

CastleMGBV8 wrote:Ralph,

14 Bolt heads are usually 36cc. chambers so you would lose quite a bit of compression unless these heads have been heavily skimmed, do you know what TVR engine these heads are off and what gaskets are you using?

3.9 blocks are normally 14 bolt unless it's an intermediate block with provision for cross bolting.

Re the cam, personally for a road engine with modded heads I wouldn't use more than a Crower 50232, V8 Tuner usually has them on special offer for approx £130.00 use with Hi- Rev lifters to allow 6000 RPM.

Kevin.

im using the 50233 on the road

TVR put heads on all cars 3.5,3.9,4.0.420,430,450,460,500.... They might even just be basic items, or they could even be the best thing since sliced bread...

Chim/Griff cars with 14bolt heads used composite gaskets long before LR did.

Caveat Emptor?

thev8kid wrote:

CastleMGBV8 wrote:Ralph,

14 Bolt heads are usually 36cc. chambers so you would lose quite a bit of compression unless these heads have been heavily skimmed, do you know what TVR engine these heads are off and what gaskets are you using?

3.9 blocks are normally 14 bolt unless it's an intermediate block with provision for cross bolting.

Re the cam, personally for a road engine with modded heads I wouldn't use more than a Crower 50232, V8 Tuner usually has them on special offer for approx £130.00 use with Hi- Rev lifters to allow 6000 RPM.

Kevin.

im using the 50233 on the road

Tony,

Yes but you have a 4.6 engine with a much longer stroke and heads that will make use of the cam, your also using rhoads lifters to soften the bottom end which all makes a difference.

Kevin.

them rhoads lifters sound like a good idea to me, either way i expect i will go for 232 or a 233.

im trying to achieve not race power, but a smooth engine which will happily rev freely, so i want enough bottom end, but also a nice top end, got good engine management, so just tryign to find right heads an cam to give the type of characteristics i want.


Ralph

Right more info,

the inlet ports are 43 x 26mm,
exhaust ports are 38 x 26mm

apparently the chambers will have been blended but cant see as they have valves in.

and i dont know the valve sizes an he has yet to measure the CC of the chambers for me.

does this suggest a reasonable amount of porting? in comparison to buying a set done by V8 developments etc?


Ralph

looks like I can see bullet valve guides which is good!
Also looks like the ports have only been matched to the manifold. With not much meat being removed from the throats?
But the area behind the valve guide has been cleaned up somewhat.

CastleMGBV8 wrote:

thev8kid wrote:

CastleMGBV8 wrote:Ralph,

14 Bolt heads are usually 36cc. chambers so you would lose quite a bit of compression unless these heads have been heavily skimmed, do you know what TVR engine these heads are off and what gaskets are you using?

3.9 blocks are normally 14 bolt unless it's an intermediate block with provision for cross bolting.

Re the cam, personally for a road engine with modded heads I wouldn't use more than a Crower 50232, V8 Tuner usually has them on special offer for approx £130.00 use with Hi- Rev lifters to allow 6000 RPM.

Kevin.

im using the 50233 on the road

Tony,

Yes but you have a 4.6 engine with a much longer stroke and heads that will make use of the cam, your also using rhoads lifters to soften the bottom end which all makes a difference.

Kevin.

dont forget i was also using the said cam in the 3.9

if they are 36cc, i presume i can just skim them back to 28 or tad less?

few more pics, any estimate on how much these will improve an engine? or how they compare to those sold by V8 developments?

im just trying to work out if its comparable or if i should just get a set done.

really i want close to 250 bhp, from a 3.9 with a 50232/233 cam with emerald management, which doesnt seem to over the top.

also do the valve sizes look standard?


Ralph

Hi
I would measure those, they look skimmed to me, there is a fair bit of squish area on those heads, and you don't get very much on un skimmed heads.
They look nice heads, clean them in the dish washer up they should be ok, but I have no idea how they flow, cant you get both choices on a flow bench and choose the best ones?
Best regards
Mike

i dont have them yet, they have been offered to me, if i buy them i will measure them, an calculate head skim from there.

more i think i probly will go for them, is there any problem at all with bolting 14 stud heads to a 10 stud block? i see in pics often with 14 stud heads with the extras just blanked off?


Ralph

Valves look standard but its hard to judge - get them measured. 250 With stock valves will be a hard ask. However big valve heads with a poor port job will also be a hard ask to get to 250BHP.

They do look extensively ported though but its easy to hog out ports too far for a stock valve size and end up flowing less than stock

The port should never be greater that .8 of the valve

Andrew