boosted crx-r

just wondering what sort of power or boost levels that the stock b-series valves are good to before they need to be replaced. also what aftermarket valves has everybody had the best success with? i have a type-r head that i'm looking to make around 500-600hp on and need some advise on what direction to go. thanks -mike

boostedEF91

Its not the power level that valves are good to. its how far you are going to rev the car. if you plan on revving to the moon then put valves and springs in it. stock valves and springs are usually safe till 8500. unless you are putting in a set of cams then you will need valve train parts. super tech and skunk2 are great companies.

boosted crx-r

planning to rev around 9500rpm since most aftermarket springs are good for 10 - 10,500rpm. i don't know whether the stock valves will stand up to the extra heat and boost pressure or not. if i do go with an aftermarket set what is the best way to "seat" the valves. a honda tech. said to use a valve grinding compound. i don't have any problem building motors just gets a little sketchy for me when it comes to valvetrain. thanks again

srmofo

well if youre building a new motor capable of 500-600hp, and assuming that you are doing it the correct, non halfassed cheap way. the head is already gonna be at the machine shop (at the very least you wanna have the deck checked) just have a valve job done. then they're just drop and go.

92redhatch

I've always been told stock valve are good to 600+. If you want to rev high you buy aftermarket springs and retainers but you don't need as valves.

pauld

I've never quite understood as to why people want to rev out to 9000+ rpm. The vast majority of B series engines just dont make any more real power that high up. Sure it will rev out that high, but for what? a "big" dyno number?
Peak torque is around 6500-7000 ish rpm, and slowly falls off from there.
All the extra stresses on the motor as it screams past 9000 just dont seem worth it to me.
I know this will start a huge uproar, but getting a great torque number just seems to make a car WAY more fun to drive than a revver that doesnt really pull any harder as it winds out.

RPM= Ruins Peoples Motors (larry widmer - ENDYN)

cjordan

iTrader: (1)

stock valves will handle 600whp, if your going with an aggressive profiled cam or something then i would recommend swapping valves along with retainers and springs obviously.

runsfromdacops

is going to be heat as well as rpm you should think about.stock valves are fine for a 500-600hp setup.
what ever you just dont buy super sanp (super tech)valves.

093turbo16

iTrader: (2)

Every motor build I do from now on I will be replacing the valves with either brand new OEM replacement valves or an aftermarket set.

I lost a whole motor/head/etc from breaking the tip of a valve off at 9500rpm. It isn't worth keeping the stock valves that came in the head when an extra $200-250 could have saved the motor.

YARO.

1. for drag racing purpose. You want to be able to trap the 1/4 mi in 4th gear and revving the motor higher is the way to do it. Also you are very wrong with power falling off that high. It depends on the cam setup and size of turbo. I've seen cars that never drop off the torque curve revving high. So is all in the setup.

boostedEF91

what are you even talking about... did you even read the post. i said its not about the hp. its how far he is reving the car.. you need to read more clearly before you go commenting my post and its pretty dump to build that big of a motor and not put new valvetrain in.

boosted crx-r

^^thats the reason i will be reving that high^^ i have a jdm type-r tranny with a quaife that i need to be able to make to the end of the track

boostedEF91

well to end this discussion just get valves springs and retainers to keep your setup safe and reliable.. then you'll never have to worry.

pauld

OK - good reasoning for your RPM desires. I thought this was a street car with yet another
"I wanna rev it 2 9500 cuz its good" owner. Build the valvetrain, including valves.

Tony the Tiger

I am all about revving.. If the motor makes power up there, then you'll be going faster.

I was on stock valves for the longest time... I had about 62000 miles on my built motor with stock valves. The most power it has seen is 650 WHP, and the motor has always been revved to 9500RPM constantly. It started out as a DD car, and then became my weekend roadracing car for a few years, and then became more of a spring/winter car and highway tire muncher ever since...lol But it has seen constant high revs with a lot of highway pulls I have done (sustained 9000+ RPM for minutes at a time).

boosted crx-r

thanks for all of the input guys. . . i think i'm just going to go ahead and drop another grand on the valvetrain. i've already spent 15 so whats another thousand i guess. better safe then sorry

extralargenog

iTrader: (1)

This thread .... lol.

Anyways OP ... STAY AWAY from Supertech valves, They are garbage (I DO use their springs and retainers).


Go with Ferrea 6000s... Before anyone asks WHY, I suggest the search function. They break... they break without interferance... Moreso than others, its well documented in more than tens of instances.


I agree stock valves arent worth the risk when valves are fairly cheap.

Joseph Davis

Most aftermarket springs are very much NOT good for 10-10.5K rpms in a turbo motor. You are talking 100 in/lb spring rates and large seat pressures, minimum, and the camshafts become consumable items.

To touch on what the fat man above me says, I've no problem with the Supertech/KMS springs but I've seen a couple sets of their B-series valves fold over in person. I'm also not a big fan of revving past 8-8500 for longevity reasons unless you have a trailered drag car or the deep pockets needed to repair expensive toys. It's stupid easy to make a lot of power these days and have it hold together for a nice duration if you have a good relationship with the machine, maintain it, and practice a little common sense.

blaze the chemi

Have you thought about changing the FD and/or gears to a taller one so you wouldn't have to rev it? I'm going to rebuild my head with a CTR/ITR valve train only for the safety and reliability of the system. It's been proven. Besides my head is now 20 years old and could use a fresh(er) setup.