I lost an engine before due to valve float and over revving w/turbo. I power shifted at 8000rpm with no rev limiter and the piston smacked the valve, broke it and the cylinder swallowed the valve. I think upgraded valve springs and retainers, actually even just the springs, would be good insurance. Need to hear what you think?
Probably many people out there will tell me they have stock springs....I had them for 2 years with turbo too but im not going to go the same route again...I learned my lesson about stock springs. Im only going with 8 psi on a basically stock motor b18c1 and I didnt want to spend too much $$$ right now. So as to the head should I just get the springs? Also possibly keep redline at 7800? Please give suggestions. Thanks!

 

Good set of springs and retainers are a must. Light weight retainers because the heavier the retainer, the easier it is to float the valve. They are good insurance plus are stronger. If you break a retainer, the valve will drop into the cylinder.
An important measurement on turbo springs is their seat pressure (spring pressure when the valve is closed). Remember, you have the boost pressure pushing against the bottom side of the valve which negates some of your seat pressure. The turbo trys to push the valve off the seat when it is closed.
Pick a good set of springs and retainers and have a pro set them up.
Get your rev limiter programmed back into your ECU and you should be cool.
Earl

 

Thanks. Got what I needed to know.

 

I will go ahead and share my 2 pennies as I just recently had an incident similar to your self but yet different. My head for fortified with crower springs and retainers but with stock valves. I made the stupid mistake of not setting a rev limiter like yourself. I was shifting at 9500.. missed a shift a few times and the rest is history. Now... one thing that was intresting was that the head on the valve seperated from the stem. Which means that possibly the spring pressure was too much for the valve at that high of rpms. I might also add that there were stress cracks on some of the other valves but were unharmed. Had I floated the damage would of been alot different. My valve stem was still in the head. On the other hand the valve head that little bitty piece of **** cost me a freaking boat load as it distroyed my je pistons, my head, my turbo, and then ended up inside the intake manifold. Needless to say, I now have to get my block resleeved and have to run a stock b16 till I can send it off. Oh.. and uh, I now have a REV limiter at 8200 and use stainless steal valves a la crower type.


[Modified by GSRev, 10:16 AM 11/25/2001]

 

So would it be necessary to get the exhaust side springs and retainers? I ask because it seems as if the pressure would be forcing the valves closed, not open, on the exhaust side.

 

They end up looking something like these?



Yeah, I break alot of parts

Someone told me once, drive it like oyu hate it, or you aren't really racing... My wallet shows how true I hold those words.

 

Damned that brings back some awfull memories!

 

Exh valves will float just the same as intakes. Quit trying to risk everything to save a few $. Stainless steel valves are great for a turbo as they resist heat and subsequent failure. You asked about insurance

 

I actually didn't ask the origonal question, I was just saying that the logic you described didn't work the same on the exhaust side. That being said, it probably wouldn't be much more $ or trouble to get both the intake and exhaust springs and retainers done, especially if you;re going to stainless valves all the way around. I just don't hear much about people upgrading the top end to go turbo. I can definitely understand that stainless valves would be a good idea to hold up to more dramatic heat cycling, I'm just not fully convinced that a turbo car will float valves easier than an NA one.


[Modified by Bert1, 11:39 PM 11/25/2001]

 

GSRev, Earl, SirKid
thanks for advise...Im new to this board but have been into racing for several years already. Im going to get rev limiter but the ignition cut off from a 6AL not from ECU. My standalone is gonna be a hondata stage 3 w/ boost. Definately going with stainless valves, springs and titanium retainers (crower or Ferrera). I've always wanted oversized intake valves so I think Ill get that now. Putting in turbo, intc on Dec 13. Already got JE 9:1, Crower rods, T3/t4 hybrid .63, Spearco intercooler, LS tranny, CM stage 4, SFP manifold, Greddy power extreme waiting for install...95 black GSR....no time slips yet still building....hopefully run 12s first few times out to track...some day 11s!

 

I think my post was a little unclear. All things equal, the exhaust valves can float as easily as the intakes. But seat pressure has little (if anything) to do with controlling valve float.The SECOND issue is spring seat pressure of valve springs between turbo and non turbo cars. One problem with stock springs is the seat pressure must be increased to compensate for boost pressure (intake side only, of course). If seat pressure is 80 lbs installed and you are running 20 lbs boost, your net pressure is only 60 lbs.
Earl

 

i am interested in what I need as well. Just tell me the parts and the estimated price for each.. I have turbo LS and am planning on running 15psi street 18psi track. I already have built block, waiting on hondata before I up my boost. I just dont know what to do to my head. I am looking for insurance as well. Thanks a million.. I dont understand all this head talk so you might have to be gentle with your reply..

 

Ahh, I understand now. So on the valve float issue it should be equivalvent to am NA set-up, so with the stock rev limiter the stock springs are retainers should have the same resistance to float? WHat would be the consequences of the decreased seat pressure? I'm guessing it may be possible for some of the charge to seep back out of the cylendars during the compression stroke thereby decreasing effective compression and robbing power?

 

Yes, valve float is the same for NA as well as FI. The problem with the turbo'd motor is that it just rpms so damn fast! Without a rev limiter, it can get away from you.
Correct on seat pressure also...grasshopper

 

haha. Thanks for the knowledge! Just trying to understand all these turbo nuances before I take the plunge.

 

Once you go turbo, you can never go back

 

One more thing... (slightly OT) is the stock rev limiter ok while running a turbo or can damage be caused by ocassionally hitting it on accident? I've heard of "soft" rev limiters but am not sure on the differences.

 

Here's Crower's page listing the Stainless valves, Valve springs and Titanium retainers we're talking about... http://www.crower.com/honda.shtml#b

Looks (for my GSR, LS is cheapers) it would be ~$560 without the retainers (no price listed.) Earl, are the seat pressures enough on the regular GSR dual springs? (1.000=138# 0.900=170# )

 

Never heard of a soft rev limiter but the act of hitting the rev limit will not hurt the motor assuming the rev limit is not set too high. Stock GSR springs will not work with high rpm turbo use. I learned that the hard way for the mere cost of a set of exhaust valves. Check out Web Cams prices on springs and retainers. That's the kind I use with no problems yet! I'm sure Crower's springs and retainers are great also.

 

Sorry, I meant the regular Crower GSR dual springs as opposed to their Eibach GSR spring.

 

do they have a website (webcams) to check their products and prices out??

 

Their website is http://www.webcamsinc.com. Kind of a poor choice for the company name imo since it makes searching on it difficult, but whatever. The have a set of "turbo" valve springs and Ti retainers (pn VC-A03) for $395.00. Their stainless valves are $30/ea, so $480 for a full i/e set. The Crower stainless valves are only $267 for a complete set. Is there any reason one couldn't use the web cams springs and retainers with the crower valves to save a couple hundred bucks? I definitely like the idea of a valvespring designed specifically for a turbo app.



[Modified by Bert, 9:14 AM 11/28/2001]

 

And what would the total be for all that stuff going through Crower?

 

Springs and valves would be $560 through Crower... no price is listed for their retainers, but I'd make an uneducated guess of around $100 for the retainers. The webcams Springs and retainers with the Crower valves would be $662, but that is of course with the retainers. The full Web Cam set-up would be $875. I think I'll be going with the Crower valves/Web Cams springs, retainers since that way I'd get spring specifically designed for turbo.

 

No experience with Crower GSR springs. If you call Crower and ask for tech, they will be friendly and answer all your tech and pricing questions.
Web Cams started with motorcycles. They say their expertise is with overhead cam engines and thus graduated into import OHC applications.
I use their cams, springs, retainers and ss valves with no problems to date. Currently at 440 WHP with my B18C and my goal is about 510 WHP. Web's tech help is also good and will probably come from a girl
Earl