What is a decent minimun needed for FI reliability, I know that these flow awesome in OEM form. I would love to go balls to the wall, but unfortunately have a budget so I only want to do as much as needed for Turbo longevity. This is primarily a daily driver with the occasional track day.

what is in the plans so far:

a resurface, 3 angle grind
supertech inconel exhaust valves
supertech nitrate intake valves
stock springs
AP2 retainers
stock valve seats

how much of a difference in compression do the Dish or Flat faced valves provide?
Unfortunately the inconel ones only seem available dished and I already have low compression pistons.

what are the pros and cons with going with the maganese bronze valve guides or stock valve guides?

Any other recomendations?

Thanks,
Joe

 

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I don't think you will see much gain for the 3 angle valve job unless you are NA.

If you have the money I would invest in the guides. As with any friction surface the guides wear overtime, with new guides you will tighten up the clearances again. As far as the manganese (SP) is concerned, according to the advertisements, is supposed to hold up better then the factory guides.

There is a Very small difference in the two but I would suggest the dished valves, you want the smallest amount of material on the valve you can get to minimize weight and maximize heat dissipation.

As far as I know the stock valve seats are excellent and do not need replaced unless there is an issue with them.

If you are going to spend the money springs may be a good investment especially if you are going to be on the track. Compared to the factory, there is a huge difference which is very evident in the retainers.

Another upgrade would be a full set of Inconel valves rather than the Nitride coated, but this would be more for the track not street.

Are you planning on having the head surface decked?

You can plug the AIR injection ports while the head is off.

Oh, and don't forget the valve seals, they are cheap and easy to replace now.

 

Great info Thanks!! yup that link is what got me looking at Inconel valves,
I'll probably do the nitride intake inconel exhaust combo both in dish. I was just researching the strength properties of inconel.. I love exotic metals.

For turbo applications I have also read of people going with slighty bigger set of valve +.5mm on the EXH side with success. Any thoughts of this? I remember long ago reading that FI cams always came with a more aggressive exhaust profile, which makes some sense of this, but valve size and cam lobe almost do the same but is also somewhat different.

 

i think the problem your gonna run into here is that, a shit ton of power can be made from a stock uncracked motor. that being said, i dont ever remember someone showing a before/after with a "built head" on the same setup.

some people have put on heads and actually lost power, that i do remember. guys can make 600-700 on oem head parts no port no valve job.

SO, the question you have to ask yourself, is why am i doing the head when it flows so well? am i going to make 800+? i would hope by then having the head done would be an improvement.

 

Personally I would just put the parts in the head to make it last. It makes plenty of power stock (cams, ports, etc). You won't get away with stock valves, springs, guides, retainers for long if you are making big power. I know the power can be made, but the longevity won't be there.

 

oh, this is new to me. so is there a set powerlevel that the stock valves, guides, retainers give up on? i coulda sworn you can do 500-600 consistently on them.

 

Good point, and my answer to this was reliablilty. For this Flow is some thing secondary-- it's one of those things while the head is off "I might as well" mentallity. When I read of people dropping valves, and valves warping it would probably be wise to slap on some beefier valves and AP2 retainers and call it a day, but in that perspective the question is will there be a beneficial yield to upsize? without any data that is hard sell definately.

 

I went with newer AP2 Valves (11,000miles on them), I hope they last, otherwise going with the Supertech Valves would have been a lot cheaper than replacing the motor

 

I honestly think it is a mistake Joey. Why skimp on something that only will cost you an extra 700 for EVERYTHING? (valves, springs, spring locators, retainers, guides) It just makes no sense to me and I have seen dropped valves with the S, including some that the valve itself broke.

Your only as good as your weakest link...

 

yeah, The springs/clips/retainers/and guides are all new, I did not want to go with Titanium retainers, the head isn't apart yet I will see what kind of deal I can work out with Lasky for the Intake/Exhaust valves alone

meehhhhhh, I just ordered the Nitrade Intake Valves and Inconel Exhaust Valves, everything else will be new OEM AP2 , more F----- money out the window