Boyle.R

When increasing boost level should your valve springs be taken into consideration. Are springs of higher seat pressure needed?

Muckman

iTrader: (2)

Id say yes. Increasing manifold pressure (exhaust and intake) lowers effective valve spring pressure.
Any kind of valve system that uses spring tension would suffer the same affects. Look at blowoff valves and wastegates.

Turbo-LS

iTrader: (4)

I'm going to say yes and no. It really depends on what the purpose of the car is and what kind of power out of what turbocharger your looking to make. Theroetically yes you should but in real world stock valve train has been known to withstand some abuse and boost pressure behind it

Boyle.R

22 psi on a Garrett 57trim, will stock type r valve train be ok?

Charlie Moua

iTrader: (3)

muck is correct.

however, people in the past have been able to just use stock valvesprings with zero issues for mild sub 450whp application (medium size turbo under 25psi)


if your building something for more than 450whp, don't try using stock valvesprings cause it's not worth the risk.

bang for buck i would get rocketmotorsports snap fit valvesprings.
55 lb. seat and 186 at .500” lift

Boyle.R

Where can I buy RM valvesprings? They can be used with stock retainers I assume?

Julio@Bisimoto

Factory valve springs where never intended to handle the extra forces behind exhaust valves. With the combination of higher rpms and 22psi behind your valves you may experience some valve float.

My opinion, it is worth the few extra hundred bucks for a proper set of springs and titanium retainers to avoid float. Not to mention, if later you decided to throw in some hot cams you do not have to worry about swapping out valvetrain again. Hit me up and I can hook you up with a good deal.

Boyle.R

I've heard mixed reports on using TI retainers. Can stock retainers be kept or a replacement steel retainer like BC sell

Charlie Moua

iTrader: (3)

valve float ..... only seen it happen once on a stock LS head pushing the limit of his turbo (was at like 28psi only 385whp) and the power would break-up up top.

i would be curious to know when bvtec springs would rbegine to cause valve float.
I've yet to see myself or know of online people facing that issue.

Muckman

iTrader: (2)

I bent an exhaust valve from an overboost/backfire combination on stock valve springs once. Pretty sure that was valve float. Oops.

Boyle.R

Will supertech valvesprings work with stock retainers?

carlos8

yes, but for safety use aftermarket retainers is the rule.

For example i don't use tI or cs retainers. i use s/s from a company hypersonic
the stainless steel don't wear and contaminate the oil.

Boyle.R

Ok I've found that Supertech do steel retainer which work with OEM keepers so i'm thinking of buying Supertech springs and retainers. Anyone had any issues with Supertech valvetrain?

carlos8

yes, your are fine with stock keepers.

wantboost

iTrader: (2)

A good set of tool steel retainers will only run you about 60 bucks.... weigh less than stock and much more durable.. I don't run titanium on any street motor that I build

Boyle.R

Any link to where I can buy these?

There is two choices for Supertech springs, 70 and 85 lb seat pressure. Would the 70 lb springs be adequate for my cylinder head?

wantboost

iTrader: (2)

EBay, I'll find it and pm you although there are two different retainer sizes based on spring diameter, so you need to decide on a spring first

tepid1

Just so we are all clear.... this is not true.

It doesn't change anything about the spring, but it is potentially added force needed to seat the valve while under boost.

Be careful when upgrading springs. You need to take into affect that you will have extra force on parts that may not have been designed for it. IE: valve stems, valve guides, valve seats, valve retainers, valve springs, rockers, cams, etc. They all have an effect on another. Also, look into using a good oil to help with lubrication. Having the right oil will be key in keeping your valvetrain alive.

Boyle.R

What valve springs would you recommend for my application? Thanks.

tepid1

I know nothing about your setup. I need all the details to help. What components are in the head now? All oem? What cams? What rev limit?

Boyle.R

It's a type r head, valves, valves springs, cams all ITR. Revving to 9k. I'm considering buying a set of GSC turbo cams in the new year...

TheShodan

iTrader: (14)

I would then recommend to use the GSC valvetrain to go with those cams that you plan to use next year. I also recommend an oil that has a higher ZDDP content (Zinc) for the engine itself. The weight isn't so important as the zinc content for those camshafts. I do not know your location as to whether or not you're in the U.S. or not, so I cannot provide an accurate list of oils for your availability.

tepid1

TheShodan pretty much covered it. That should work well with a stock valve and those cams/rev limits. As he mentioned, oil is important, especially the added zinc. It really saves the cams and rockers. Cams are getting pretty aggressive ramp rates and that is what kills rocker pads. Viscosity is dependant on your engine clearances.

wunfstgsr

What oil would you recommend in the U.S for a boosted Type R? just curious, i just switched from penzoil to mobil 1. But id like to know what oil is recommended that has more higher ZDDP content (Zinc).

Khnemu

iTrader: (1)

Brad Penn