As title say's,

I'm going to be assembling my 400whp+ B16 over the winter and am unsure whether or not it would be a good idea to upgrade the GSR valves i have here. I will be using Rocket motorsport valve springs and TI retainers (GEN2) and i will be planning to rev to 9000+. I'd imagine a higher valve spring pressure combined with high rpm and higher cylinder temps would have some influence on whether or not it would be a good idea to upgrade them ? ?.

The car will be a daily driver with the odd track/drag strip day.

Thank you for your time.

P.S. Could one of the mods please stick a "r" in aftermaket please

 

Usually most prudent people use aftermarket valves when the original ones have either been bent or have so much carbon on the valve that it literally has fused itself to be part of the valve. Using a flat-topped valve helps with some increased compression, but not necessarily a gain in horsepower.

There is some ambiguity in the use of "oversized valves", though most Americans with our general philosophy of "bigger is always better", tend to use oversized valves with the thinking that it will allow more ingested air to come through and discharge, but that logic is debatable. Some companies that make camshafts specifically state not to use oversize valves, though I honestly am not sure as to why. If Skunk or ALL MOTOR or others in the all motor forums would chime in their input, it would make a great discussion.

 

with oversize valves you run the risk of the valves crashing into each other during overlap, depending on the cam of course. your v2v clearance gets smaller.

 

I.c. So, I guess I have to ask the dumb question... why offer it, if the purpose is to correct a valve seat problem which if caused by oversizing the valve opening?

I guess I've run them for years, without any issues, and only NOW hear about these additional risks.

 

The valves i have aren't in bad condition really, they could do with a slight decoke but thats about it... I know our valves are a two piece welded design as i have tested them with a magnet. Its the fact that there welded what concern's me. I know the weld is going to be damn strong BUT i doubt it will be as strong as a one piece forged design.

I'll drop ALLMOTOR a pm with a link to this thread. Please let people know that you feel will have a good input.

Thank you

 

you can run oversized valves if you check v2v at different degrees on the cams, but a lot of people just throw things together half assed and then end up with problems. some cams actually require you to seat the valve deeper in the head.

oversized valves can help with flow, that's why they're available.

 

I would expect more than a typical flow answer, but I'll see what other have to input.

 

They are supposed to have a higher tensile strength to accept the more agressive slapping on the seat due to spring rate from performance springs/cams, and also prevent stretching in high HP motors. So i hear. When are they too be used, idk?

 

you should always replace exhaust valves in a rebuild. those things have a finite life and will frag on you eventually.

as for aftermarket, ferrera is lighter but the exhaust valves should ideally be inconel in FI apps, ferrera, at least their standard line are just 1pc stainless. i know ferrera makes inconel and titanium valves, just can't remember if they do for honda.

taken from manley about inconel

 

I'd imagine heat would come into it to, specially for the exhaust valves. Wouldn't valve stretch be more in high rpm use ? Actually, i know a engine that was blown to pieces due the valve & rod stretch at just over 9000rpm.

 

Thank you for that Racebum.

 

Some info on Ferrea's competition plus valves (There top valve's)

"COMPETITON PLUS VALVES
Ferrea Racing Component’s Competition Plus Valves have built a reputation as the industry’s most reliable racing valve. Ferrea are dedicated to providing the absolute best product on the market.

Ferrea's extensive R & D programs provide technological enhancements that are implemented in each of their competition plus valves. They are engineered for high rpm’s, high horsepower racing engines, and are chosen by many top Drag, Oval Track, Road Racing and Sprint Car teams.

To manufacture the valves Ferrea uses special aerospace quality alloys, including the EV8-Z18, which provides high tensile strength. An exclusive two-step slow forging process ensures proper grain flow and virtually eliminates any damage to the material structure. The valves are then heat-treated and stress-relieved over a 48-hour period, which is the crucial base of Ferrea's molecular integrity. These valves feature avionics-quality hard chrome along with a specially applied hard tip. Ferrea's engineering staff spends countless hours conducting flow bench tests to achieve an optimum balance of flow, velocity and efficiency in the design of these valves. As a result, these valves incorporate smoother radiuses and unique undercuts. These exclusive features are what make the Ferrea Competition Plus Valves unequalled in performance and reliability!

The evolution in volumetric efficiency of today’s competition engines has increased the average engine EGT. These higher ExhaustGas Temperatures decrease the longevity of the valves as well as creating higher levels of metallurgical fatigue. These increased stress loads create an environment in the engine conducive to valve failure.

The exhaust valves in the Competition Plus series are manufactured from Ultra High Strength, High Temp Nickel Stainless Steel Alloys. Ferrea first used this material with great success during the development of a very high stress, high temp endurance racing program.

Listed below are some qualities of the Competition Plus Exhaust Valve material:

• Tensile strength increased by 20% at high temperature
• Fatigue resistance increased by 20%
• Valve seat life increased by 25%"

 

I know the OP was about valves but I believe the springs are more important. When you add intake and back pressure to the system it reduces the effective spring pressure making valve float easier.

 

As far as stock honda valves go i found this, its also appears there is EV8 alloy on the intake. For 400WHp i would keep stock valves.

 

Yes, thats a good thing to mention. Thats why i went for a new set of aftermarket springs.

 

Good find !!!

 

if stock is ev8 and inconel i would stay there. you can use more spring pressure if need be to make up for the extra few grams.

funny, oem is actually stronger metal than the average aftermarket

 

thats why i love and use oem honda if at all possible.

ive been using the same oem valves/head in a 400-500 hp motor for 4 years now. total mileage is about 40,000 at that power level. the only issue i had was one time i had to get some of the exhaust the valves touched up by my machinist after getting a little too aggressive on the antilag. even so, it wasnt anything bad enough for me to need new valves and i didnt loose any compression from it

 

650+ here on stock head everything but springs

 

Fixed

 

sanman, how many hits have you made with stock valves? i'm going for 600whp and i'm also debating on if i should go aftermarket valvetrain. i don't wanna waste a built engine on a valve breaking.

my concious is telling me to just buy valves....

 

**** wow man i garauntee ive had over 250 hits

ive been through 4 short blocks now, and on the same head lol

oh and then back on a stock short block and now on a built b16a2 and about to get tuned out again.

i do have upgraded springs in it and thats it.

 

Bump for info on oversized valves.

I would like to know :

What effect they have on the engines volumetric efficiency (VE) / Powerband.

What effect (if any) they have on low & high engine speed combustion.

The effect on exhaust gas velocity/turbo spool.

Thank you

 

From my personal experience, I would go with aftermarket valves from the get go. I thought I would be fine with stock valves since people have said stock valves are hit and miss for alot of guys. I was apparently a miss in this particular instance. I took a chance with it and it cost me an engine after 3 days. I plan on buying ferrea comp plus everything because the way I see it, the money I spend on those now will save me lots of money on the back end. Just my $0.02.

Build specs:
84mm AEBS sleeved b18c1
CP pistons
Manley I beam rods
Supertech springs and retainers
S2 pro1 cams
PTE billet 6262
ID2000s
e85
Car made 620whp

Then:







**** luck.

 

Sorry to see that ^^^ Thats some serious engine damage.