Oversize Valves

[Lextreme II]

I have been looking at Ferrea 1mm oversize valve for the 2JZGE/GTE motor. Here are the specs:


FERREA SPEC:
Getting ready for some head work Stepping up in HP on your combo
Don't forget about upgrading your valves!!!!!!

Stainless valves for 1mm oversize 1994-1998 Toyota Supra 2JZGE-turbo or 2JZGTE 24V

Ferrea Competition 6000 series intake and exhaust valves. These valves are specially designed for racing engines that are subjected to extreme exhaust temperatures with Turbos, Nitrous, or Superchargers.

Valve specs:

Exhaust Part # F6097 - 22 degree Flo Stock Size Special Alloy
-30mm head diameter
-5.98mm stem diameter
-99.1mm overall length
-3.5mm tip length

Intake Part # F6096 - 20 degree Flo Stock Size Special Alloy
-34.6mm head diameter
-5.98mm stem diameter
-98.55mm overall length
-3.5mm tip length

MANLEY SPEC:
Valve specs:

Exhaust Part # "11123-12" - Standard size 20 degree dish
-29mm head diameter
-6mm / .2362" stem diameter
-99.10mm overall length
-3.5mm tip length

Intake Part # "11124-12" - Standard size 17 degree dish
-33.6mm head diameter
-6mm / .2362" stem diameter
-98.55mm overall length
-3.5mm tip length

Comes with (12) intake and (12)


Perhaps this link would help http://lextreme.com/valve.html What do u think? They are about $350 USD for a whole set.

 

[cribbj]

Have a look at the Manley SS valves too. Some engine builders prefer them over the Ferrea's.

John

 

[sniper]

soooooooo........how are we going to use a longer valve again?

 

[cribbj]

Trim the stems down, or have the valve manufacturer build them to the 1UZ length?

Trimming the stems is accepted practice after a valve job when the seats have recessed and the installed stem height is too high for good lash adjustment even with the thinnest standard shims.

I had this problem with my 2JZ engine but the builder chose to machine down the shims for the valves that were sitting too high. In retrospect, I wish we'd trimmed the valve stems instead.....

John

 

[Lextreme II]

The engine builder also can grind the cam loop to compensate the .139" extra length.

 

[rarson]

If we are using Supra valves and valve springs, then logic dictates we'd be able to use the Supra retainers too...

Titanium retainers... drool...

 

[SCV8]

Not sure if you'd need to have the stems hardened after cutting/machining, but likely, and the shims can break easy if they're too thin.
The base circle on the cam can't be made much smaller really, since the lift rates on the cam will be out of range for a non-roller profile.

 

[Zuffen]

Do you intend to change the valve seats to a larger seat or just machine a larger diameter hole in it.

There's no point in using oversized valves unless you use them to fill oversized holes in the head!

I don't believe you could machine 1mm out of the standard seats without risking the seat failing and (perhaps) falling out or breaking up. That wouldn't do the pistons any good at all.

This is a lot more involved than it looks.

 

[rarson]

I realize that; however, I don't have the fortune of having a 1UZ head to look at. I've heard of shops machining the stock seats on other engines, any particular reason why you don't think it would work? I hope I am not coming off sounding arrogant, I am honestly just searching for information.

Taken from this thread:

OD: 33.5/28.0mm (I/E) 1UZ
OD: 33.6/29.0mm (I/E) 2JZ

My thoughts are to use 1mm over 2JZ intake valves and stock-sized 2JZ exhaust valves, which would give about an all-around 1mm increase in valve diameters.

 

[Zuffen]

The stock valve seat is a piece of steel shrunk into the head. When you start playing with the size of the annulas you alter the strength of the seat.

If Toyota felt it would work (reliably) with a seat that was 1mm narrower it would have done so and saved some money.

If you take the question to the extreme and put a 36mm valva in there you'll end up with no valve seat.

The only way you will know is to machine it out and see how long it lasts.

If I was going to bigger valves I'd fit the 2J seats in the head. Now that will cost you heaps.

I don't see the valves as being the problem in gas flow in a 1UZ the angle of the valves and the shape of the ports has a much larger impact on gas flow.

 

[turboandrew]

Even on 2JZGTE, many have questioned the flow increases with bigger valves. Lot's of people out there making 800+ rwhp with stock valve sizes. If you were running much bigger displacement & high rpm, then maybe there is some benefit, but IMO there are many other areas to tackle first, like porting from an experienced person and cams tailored to your needs.

 

[rarson]

I think I'd be willing to try 1mm over using the stock seats. I'd rather get lighter, swirl-polished and nitrided valves anyway, and since oversize valves are common (and using the stock seats wouldn't require much work), I figure why not.

What about naturally aspirated? I realize that velocity is just as important as flow, but the ports are already bigger than the valves, so would it be worth a test? As I said, I'd be willing to try.

 

[Zuffen]

Rarson,

Let us know how it goes.

 

[rarson]

Well, sorry to say, I'll have to get the engine first. But I'll definitely be a pioneer for oversized valves if I must.

One question though. Seeing as how the 2JZ engine was designed for "performance," can anyone tell me why it's exhaust valves are 1mm closer to the size of it's intake valves than the 1UZ? Maybe it would be a better idea to go 1mm over just on the exhaust size?

 

[SCV8]

The V8 has a more natural tendancy to make power at higher revs than the six(vectors/firing order) the choice of valve sizes was likely just for tuning to the desired rpm range.

 

[Lextreme II]

I talked to my engine builder and he stated 1mm would not be a problem

 

[Locost 7]

3SGTE valves

Here is something that i found by accident, i have a few 3sgte valves around and started comp them to uz valves. the valves are very similar to 2jz valves but a tad long and are true 6mm stem, jz are about 5.9. 3sgte intake is 100.7mm long, exhaust are 99.65mm long. the valve head are almost the same diameter, so much that power wise they would prob be the same. they are longer the uz, but just a thought.

 

[toad007]

I have a 22re in my 86 4x4 yota pickup that has 1mm oversize valves on the standard seats. 1mm over in the 22r/re/rte heads is a common practice. Just food for thought.