Does a turbo motor need heavier valve springs?

[Crawdad]

2276
Panchitos 40x35
CB 2288 cam (=K8) .549 lift with my rockers
Turbo will be a RAD X25-550.
Looking to make 300 HP at 15 psi, revving to 6.5k , maybe 7k once in a while.

Mark Lawless at CB told me I should use VW650 springs. They're super heavy. I'm wondering what the folk wisdom is on this. 40x35 valves are relatively light. I have titanium retainers. Are VW650's overkill? I suppose pressure in the intake tract is trying to keep the valve open, so you might need a heavier spring. But you also have higher pressures in the chamber, trying to force the valve closed.

What is the consensus on valve springs in a turbo motor?
Thanks y'all.

[blue thunder]

I would definitely use a set of good quality dual valve springs, although 650's seem to be a bit overkill IMHO. I am not familiar with the cam you use, but if it is a 'steep-ramp design', heavier springs are recommended.

[my_medusa]

Use Numbers 1019
Chim them to your needs and rodney's recomandations.

https://logmech.se/eng/products/engine/ ... cessories/

[Bruce.m]

I have no experience but did some research on beehive spring fitment. The thread is in the type4 section. The downside is the lack of collective experience in VW uses.

[slayer61]

I think you know the answer already...

Mark Lawless at CB told me I should use VW650 springs.

Seems like a pretty good recommendation to me.