fitting bigger valves

[swedge]

to a GTE head?

35mm inlets, and 32mm exhausts is that right?

whats involved in fitting bigger valves apart from buying bigger valves and getting a machine shope to fit them

how big can you go? is there a limit?

what about valve seats do they just get cut away to fit the new ones?

where can larger ones be bought

thanks :)

[mowgli]

the big block 8v heads & also the bmw 318 8v heads have suitable looking valves.. you might get away with getting the existing seats re-cut, but the ports will need to be cleaned up. its basically a b+ spec head, but obviously the devil is in the port work

[swedge]

the big block 8v heads & also the bmw 318 8v heads have suitable looking valves.. you might get away with getting the existing seats re-cut, but the ports will need to be cleaned up. its basically a b+ spec head, but obviously the devil is in the port work

yeah ive been reading a few sites about larger valves etc

what would be a decent size to enlarge by? what about the distance between the valve seats im guessing that would be a factor to how big you can go

[swedge]

anyone know the valve length and stem size of a gte valve?

[mowgli]

i'll go & find my online catalogue link, it has a list of valves for most engines.. it is a huge pdf & its hardly bedtime reading...

http://www.pngclub.com/forum/showthread.php?t=163055&highlight=online+catalogue click on the ks engine parts

[swedge]

right so looking at that catalogue

E16SE and C16SE valves are
INLET - 38mm x 7mm x 101.1mm
EXHAUST - 31mm x 7mm x 101.1mm

20SEH
INLET - 42mm x 7mm x 103.8mm
EXHAUST - 36.5mm x 7mm x 103.6mm

i gues they would be way too big plus thier a tad too long

[mowgli]

the followers would take up the slack.

[swedge]

hmm interesting i dont have a E16se head to check sizes between valv seats etc

for examples sake if i were to fit those valves there would have to be at least a 4.25mm gap between the valve seats (exhaust-inlet) and to the flat part of the head not sure what its called the bit that gets skimmed

am i right?

[swedge]

would they need new valve seats?

[mowgli]

probably.

[swedge]

thanks very much for your help as usual moqgli :) rep given

[swedge]

You must spread some Reputation around before giving it to mowgli again.

or not

[mowgli]

don't worry swedge

[C612DNM]

I had a long chat with the Late Mr Blydenstein about Nova GTE heads, and valve sizes.

It was his opinion that the B-Pack head was as good as it needed to be based on the size of the ports, and use of up to 45DCOE's for inlets.

The Nova Challenge rallycross cars had very little in the way of modifications, other than Gp.A Cosworth Pistons, a pair of 45's, a solid lifter cam (AST9 rings a bell), a 40% ZF diff, and the usual rallycross beefing up/setup.

They produced about 170-175hp with a stock head.

My own GTE race car was the culmination of a lot of work with Bill, Kent Cams, and a few others. I hit a plateau at around 165hp, bearing in mind I was using 45mm bodies, which got our heads scratching. While the car had grunt, it had no whiz! Bill got me to check the cam, which I shipped off to Kent and they found that it had been mis-ground, and were surprised that I got as much out of it as I did! It was a NV083 which I'd tested from development. I opted for the AST9 on the advice of a very nice man at Swindon.

With that in, and a trip to the rollers, saw an immediate 10hp jump, and culminated with plentyful rod failures, which on first inspection looked to be big end bolt failures. After a few engines in the skip, it took a final failure to pinpoint the problem - the rods. At 165hp, they were teetering on the edge of life, but the extra 10 sent them to Beachy Head!

Bill was right, the head (B-pack with std exhausts) could easily produce plentiful power.

BUuuuuuutt... me being a racer - always wanted more.

The outfit that carried out my engine machining were friendly with a chap by the name of Nick. Nick did heads for Mountune, and had recently done a load of heads for Williams' touring car outfit for their Renault Lagunas as they weren't getting the performance they needed out of the SoDeMo works engines. I got a new head for Nick to work with, and his opinion was up a few mm on each valve, and using rimflows for inlet, and regular stainless for exhausts. The devil is in the detail, but the new steel internals engine with Nick's head, AST9, and 45mm bodies produced another 10hp on the rollers. Mr Baldwin was impressed!

The final key in the package was the failure of the MicroDynamics fuel "computer". A change to DTA E48 and a mapping session with the Master Greenauld led to another 5-10hp top end, but bags more torque mid-range.

So. What are you after? Fast-Road/Trackday/Rally use? = B-Pack Race use? = B+ (if you can find one) - or maybe a Ric Wood job (CNC Heads).

Nick's retired now, he doesn't do heads anymore which is a shame.

[swedge]

Its will be used everyday so don't want to go nuts

What I want to do is

Fit bigger valves (advice on sizes)
Gasflow
Carbs
Cam but nothing lairy
I've also been reading about getting the bottom end balanced and maybe lightened
Lighter flywheel
F13cr

[swedge]

Surely standard rods n pistons will be fine with that?

[stevenf]

If you can get in touch with bill falconer from earlston he could prob give you some good advice. If you google bill falconer engineering you will be able to contact him through there. he is the bloke who runs the 2.3 nova with the 4 wheel drive in the autocross races.

[garyc]

check out REV valves http://www.gsvalves.co.uk/sourcehtml/RECMasterValveCatalogue.pdf they will be waisted stem as well as bigger valves.

REC 439 Group A 38 .0mm/1 .498” Inlet
REC 444 39 .0mm/1 .535” Inlet
REC 440 Group A 30 .8mm/1 .215” Exhaust
REC 445 31 .8mm/1 .254” Exhaust

[swedge]

for anyone interested

REC 444 @£14.50 each
REC 445 @£14.50 each

plus P&P and Vat, unless a VAT no. supplied



arent the rec439 and 440 the same size as standard?