I've got a 1998 ITR head with about 70k miles on it. I'm planning to boost my motor with a GT28RS turbo running 1 bar (about 300whp).

Is it safe to use my stock type-r valves with this much boost? They are afterall almost 10 years old.

I've heard that oem ITR valves suck with boost because they are too thin (due to being light), and will break after a while because of the heat generated by the turbo. Is this true?

 

Thats a good question? I know they're good valves but i forot they are light. They do take heat well better than a stock gsr valves. People say to build up the head cause thats where the power comes from!

Goto tunerschoice.com check them out. they have good deals on stainless steel valves at a ok price

 

I think you would be fine many itr's have been succesfully boosted. I would think if you had the timing retarded an excessive amount you might start to have problems with head build up in the exhaust valves/ head. Are they sodium filled?

 

The ITR valvetrain is arguably the best OEM B series for boost....you shouldn't have to worry about a thing.

I hate how people spread bullshit when they dont know what's right and what's not....

 

I would think Honda OEM parts are the best especially type R ones.

 

im using 15 year old b16 valves, 17 psi, 415whp and 8700rpm rev limit. no issues.

honda oe valves are good, especially the b series ones. if your concerned your machinist should be able to test them for stretch, warpage and clean them up for you

 

they are the thinnest b series valve.

my buddy had a failure 2 weeks ago, an oem itr head with 10k original miles on it all boosted(bought from a dealer).

10k miles and 50+ passes at the track later. were not sure if the valve broke or floated, but total destruction of the cylinder. we were spinning 9k, and running 23psi of boost making 500+whp. so it was definately pushed beyond its limits.

i dont think you will have a problem at your level. i'd run it. id just keep the rev limit around 8500.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Schister66 &raquo;</TD></TR><TR><TD CLASS="quote">The ITR valvetrain is arguably the best OEM B series for boost....you shouldn't have to worry about a thing.

I hate how people spread bullshit when they dont know what's right and what's not....</TD></TR></TABLE> Explain? just trying to learn more everyday. I was under the impression the more aggressive cams were about the only thing better for boost that you would see a benefit from?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike@synapse motorsport &raquo;</TD></TR><TR><TD CLASS="quote">they are the thinnest b series valve.

my buddy had a failure 2 weeks ago, an oem itr head with 10k original miles on it all boosted(bought from a dealer).

10k miles and 50+ passes at the track later. were not sure if the valve broke or floated, but total destruction of the cylinder. we were spinning 9k, and running 23psi of boost making 500+whp. so it was definately pushed beyond its limits.

i dont think you will have a problem at your level. i'd run it. id just keep the rev limit around 8500. </TD></TR></TABLE>

Yeah the ITR valves are light, hollow design? helps reduce valve float from less weight, best for high cylinder pressure and heat?

 

The ITR cams are known to be good for boost. The valves are light and the springs have a high tensile strenght. You'll be able to boost hard and rev high w/ a stock ITR valvetrain. I hit 9k in my GSR on 10psi w/ the stock valvetrain...just imagine what a stock ITR can do

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by quicksilver1689 &raquo;</TD></TR><TR><TD CLASS="quote"> Yeah the ITR valves are light, hollow design? helps reduce valve float from less weight, best for high cylinder pressure and heat? </TD></TR></TABLE>

yeah i meant lightest. my example was a bit extreme. its not an end all "this is when itr valves fail" type of comment. this is one of a few documented cases of the itr valves failing at high rpm. seems unlikely that they would float, being the lightweight design, and strong itr spring rate. tough to say though with 9k rpm and 23psi behind them. i guess well never know.

 

I'd stick with stock rev limiter if you have stock springs and retainers. I have a CTR motor (B16B) making 300whp on a GT28RS with completely stock head. I kept the rev limiter at 8500 and haven't had an issue.

They are the thinner than the other b series valves.