I have an extra set if anyone wants. New, uninstalled and unused.

ZVS855 v. VS855
 

Back from the dead. I'm wondering if the big difference between Summit's ZVS855 and VS855 is the part number.

VS855 is a Volvo valve spring made by Federal Mogul. Made in USA. I've seen them panned here simply because they're so cheap--a whole engine for $60.

Update--if they're Sealed Power from Summit, then it's probably the same thing. The unique UPC code is 724956648306


Additional Details

Free Height (In): 1.810 Inch
Free Height (mm): 45.974mm
Type: Single
Minimum Closed Height (In): 1.570 Inch
Minimum Closed Height (mm): 39.878mm
Minimum Closed Pressure (psi): 66 psi
Maximum Outside Diameter (In): 1.056 Inch
Minimum Inside Diameter (In): 0.708 Inch
Minimum Inside Diameter (mm): 17.983mm
Maximum Outside Diameter (mm): 26.822mm
Minimum Open Height (In): 1.180 Inch
Minimum Open Height (mm): 29.972mm
Minimum Open Pressure (psi): 175 psi
Solid Height (In): 1.120 Inch
Solid Height (mm): 28.448mm
Total Coils: 7
Wire Diameter (In): 0.164 Inch
Wire Diameter (mm): 4.166mm

O'Reilly sells them for $3.69 each.

Props to Dale for this thread! It helped me solve an issue I was having from not enough spring pressure.

Hello. On the BP6D cylinder head, is there a difference between the stock exhaust valve springs and the intake valve springs?

I have been searching for a while but couldn't find out.

This is what I was searching for I guess. Found it on this thread. :)

That's the intake side. On the exhaust side, pressures might be twice that (according to the internet).

A while back, I found that above 5500 rpm, the pressure at my turbine inlet was pushing open the wastegate valve and preventing me from maintaining my target boost, even with all the air bled off. It got worse the higher my RPM climbed.

It would not surprise me to find that I was getting 30+ psi of pressure between the exhaust valves and the turbine inlet at 18 psi of boost, especially at higher RPM.

Even with the double heavies, 30 psi of pre-turbo exhaust pressure would take you back down to nearly stock valve seat pressures.

Of course, me being a log manifold kind of guy, that might be contributing to the exhaust pressure.

edit- I went with supertech double heavies on my rebuild, should have dyno results in a few months

I wish bogusSVO was still around. His shit was so informative.

35 psi gauge is what I measured in the exhaust manifold at 18 psi of boost.

The thing about valve springs I don't get, though, is that that when the valve is closing that pressure is on both sides of it, so it really shouldn't make any different to valve float.

--Ian

Two things:

1) The exhaust runners aren't isolated from one another in most turbo manifolds. Each exhaust stroke is forcing out gas that pushes the turbine blades but it also pushes against the wastegate valve and the other cylinder's exhaust valves. I suspect that more log-like manifolds are worse in this regard. By how much? No idea. The size of turbine you run probably also has an effect in terms of how much boost/rpm gives how much back pressure.

2) During the exhaust stroke, I would imagine that it's pretty even, but what about when the piston hits TDC, just as the intake valve is opening and the exhaust valve is about to close? I would imagine that cylinder chamber would be at its lowest right about then. And I think there's a decent chance at higher rpm/boost levels that the pressure on the backside of that valve should be pretty high.

What are you using for valve spring compressors? For a number of other platforms there is a slick tool that bolts to the cam cap and allows springs to be changed with the head on.

Refference:

1
Valve Spring Compressor

2
Honda B18C B16A H22A VTEC valve spring compressor tool

Consensus:

KD Tools Gearwrench Valve Service Kit
https://www.amazon.com/dp/B004ZG5LGI..._o6RGwb4ZEVJ6W

It is possible to determine the spring rate without compressing the spring. Here is a page with a calculator.

https://www.thespringstore.com/sprin...alculator.html

In search of a viable VS855 replacement spring which shares the similar qualities, specifically fitting under the stock retainers & in a similar cost range.

I backordered these a few months back however Jeg's has pushed the date back each month - I reached out to Federal Mogul (Sealed Power) who said that the p/n is not discontinued but there is no ETA available due to no source. Their customer service experience was great for what it's worth, almost makes me not feel as bad that I'm back on the hunt for an affordable valve spring that fits under stock steel retainers (not a fan on Ti much)

Other than the OEM Volvo ones which turn out to be ~$250us, what are the other choices? The BC's at the start of this thread looks promising but there isn't a p/n available and I don't see them listed anywhere from Brian Crower dealers. Where are you hiding affordable single valve spring upgrade?

I've been through the same situation with Jegs for 3 months, it was exasperating. finally I bought the springs that I describe in my previous post and I have already installed them in my head.
You have to look for springs for volvo engine type B18 and B20, the OEM part number is 418737.
The Sealed Power VS855 It is an interchange spare part, there are several manufacturers as ITM, Perfect Circle, Sealed Power...
VS855 Interchange Part Number: 418737, 212-1241, VS437, VS1065, W11454. These are the same springs.
Here is a link where you can buy them:
https://www.ebay.com/p/Engine-Valve-...0L-L6/79503613

Thank you for your research elpazos! So funny enough, Skandix has them for around $100usd, not sure what shipping is...but looking at the same part from US dealers comes out to around $250usd LOL

I'll post my findings if I come up with anything significant in terms of pricing.

*Edit - I just emailed their support to ask for an adjusted shipping rate. Its somewhat of a flat rate at 55 EUR which is more than half the cost of the parts - hoping they can adjust. I also found that they have an eBay Store, Skandix USA - however this part number is not available from their items listed. Also emailed the eBay USA side to see if I could order direct from there. This is the route I'm gong to go, just need to figure out a more realistic shipping cost.

***Edit 2 - The Germany/Sweden side will not budge on shipping. The USA eBay side does not stock the part or have plans of getting it. Shipping is flat rate to USA up to a certain weight, turns out to be $62.38 at this time of posting with the current exchange rate. The valve springs turn out to be $126.13 That makes the grand total $188.52 for those in the USA. I may have another update however, with another option. Doing the research now.

Dang .. I just placed my Jegs order for these springs 2 weeks ago and it was supposed to ship today .. I see that the item page the date keep getting pushed back but I was hoping it was for new orders and MINE would be shipped on the correct date. Judging from your comments here I'm thinking I should just cancel my order.

Depends how fast you need them. My head just came back from machine shop from surfacing so I need a spring solution now. I'm talking to BC right now.