Yes, I must correct your allusion to Porsche. The type 4 1.7, 1.8 and 2.0 litre engines are a Volkswagen design and creation, not Porsche. There are minor details that could be Porsche inspired, but folks, the Type 4 is almost all VW!
As for the valve guides and springs, they are of high quality, and not Porsche priced, therefore a good value! Thanks for the sale you had on these making them affordable to retired folk like me. I will check on you guys to see if you will have sales on other parts I can afford to purchase. Thank-you!