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Racing Valves, Guides and Retainers for B18 and B20 Heads

vintagewrench

Active member
Joined
May 9, 2016
Location
Paradise


Getting ready to rebuild this B18 head racing head for use on my own 1800s that I run in VSCCA vintage races. It is likely that it is a Volvo Competition Services piece from the late-1960s. It was used on a 1967 1800s that was converted into a racing car when it was brand new and it went on to win the New England SCCA Championship several times beginning in 1967.

Also will be modifying B20 F head for a friend that also races.

Looking for a good source of top notch B20 racing valves, guides, springs, and retainers here in the US, but if I can't find anything I'm aware of some of the sources in Europe.

I can and have machined my own B18 to B20 conversion valve guides (B20 valves have .312 stems and B18 .341 stems.)

Anyone have any good and fairly recent experience with what might available here in the states that they would be willing to share?




 
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If you have a sample of each, send them down to REV in Florida. They've been really good to work with, pretty reasonable as well when I do the group buys for the OHC heads.

Also might be worth shooting a pm over to fidel, see what he knows as he may have some sources, though he doesn't get on here much.

One note, are you looking for stock size heads and stems or something different, as that may change things.
 
If you have a sample of each, send them down to REV in Florida. They've been really good to work with, pretty reasonable as well when I do the group buys for the OHC heads.

Also might be worth shooting a pm over to fidel, see what he knows as he may have some sources, though he doesn't get on here much.

One note, are you looking for stock size heads and stems or something different, as that may change things.


Thanks! Looking for oversized valves with .312 B20 stem size which I think is quite common.
 
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What diameter valves are you looking for? Do you know what seat pressure is required? Single or double springs?

VP has conversion valve guides in steel as well as a hi-performance single spring and retainer kit. Isky sells a dual spring and retainer kit as well.

You didn't mention valve locks but it's a good idea to use modified locks that don't allow the valves to rotate on a performance engine.
 
What's your budget ferra makes a nice valve, cam choice makes IS the deciding factor as to which spring package you will use.I wouldn't just throw massive triple springs on it....I would call comp, isky,bullet, or ultradyne, tell them your intended use rpm range final drive gearing, weight, compression ratio etc. I would see if you can get a solid roller cam ground and ditch the flat tappet action, for even more suds and r.p.m. Potential,I would ditch all the factory stuff and lean towards a nice tool steel lightweight retainer.beehive springs, and some nice round bead locks,swirl polished small stem stainless intake and exhaust valves. Then look into swain coatings and maybe get the chambers and the valve heads and piston crowns coated...it's really not that horrible for price..cams and valve train are my favorite part of engine builds.I would also highly recommend the child's and alerts zero gap rings 1.5 barrel faced first ring.1.5 napier 2nd and stainless 3.0 std tension oil rings, They are expensive but worth it
 
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What diameter valves are you looking for? Do you know what seat pressure is required? Single or double springs?

VP has conversion valve guides in steel as well as a hi-performance single spring and retainer kit. Isky sells a dual spring and retainer kit as well.

You didn't mention valve locks but it's a good idea to use modified locks that don't allow the valves to rotate on a performance engine.

46mm intake valves and 36mm exhaust. Yes, double springs and I would like to find some light weight retainers, but don't trust the aluminum versions.

Planning on using a fairly radical cam, that would work with SU's to begin with, followed by a change over Webers and VCS/R-Sport manifolds in 2020.

What kind of spring pressure would you recommend?

Yes, modified racing locks. I don't want to go the cheap way, but want high-quality stuff that will last and can hold up at 7000 rpm and more on occasion.

Would Isky pushrods hold up and are they sized at .375, are they chrome moly and light? Any light weight Chevy lifters out there that would work well with the package?
 
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Isky's dual springs are rated at 98lb seat pressure @ 1.625" installed height and a rate of 300lbs/in. Coil bind occurs @ .970". The cam profile and valve train weight will ultimately determine the seat pressure and rate needed but that seems to work well for a broad range of cams/valve trains.

VW type IV valves are almost identical to B20 valves and work with no problem. There's a performance parts/machine shop near me that stocks good quality economy SS valves from 36-50mm in even size increments. The also have Manley valves but they have a very narrow margin and I would only use them for racing. The same shop modifies new Scat hardened valve locks.

Isky push rods are chrome moly steel as are their retainers. They hold up very well to high rpm. The push rods are hollow tube 5/16" (.3125"). I like to enlarge and chamfer the holes in the head to facilitate oil return since the push rods are already larger than stock. You may need to restrict the oil to the rockers on engines that see consistently high rpm if you find oil pooling in the valve cover.

CylinderHead9.jpg


Lifters are one area you don't want to scrimp on. I once had a cheap Chevy style lifter seat fail and the push rod got stuck in the lifter which required removing the head at El Mirage dry lake bed and driving home on 3 cylinders.
 
What's your budget ferra makes a nice valve, cam choice makes IS the deciding factor as to which spring package you will use.I wouldn't just throw massive triple springs on it....I would call comp, isky,bullet, or ultradyne, tell them your intended use rpm range final drive gearing, weight, compression ratio etc. I would see if you can get a solid roller cam ground and ditch the flat tappet action, for even more suds and r.p.m. Potential,I would ditch all the factory stuff and lean towards a nice tool steel lightweight retainer.beehive springs, and some nice round bead locks,swirl polished small stem stainless intake and exhaust valves. Then look into swain coatings and maybe get the chambers and the valve heads and piston crowns coated...it's really not that horrible for price..cams and valve train are my favorite part of engine builds.I would also highly recommend the child's and alerts zero gap rings 1.5 barrel faced first ring.1.5 napier 2nd and stainless 3.0 std tension oil rings, They are expensive but worth it

Thanks, I have been thinking of Ferrea valve and they do make nice valves, I've seen some in person.
 
Isky's dual springs are rated at 98lb seat pressure @ 1.625" installed height and a rate of 300lbs/in. Coil bind occurs @ .970". The cam profile and valve train weight will ultimately determine the seat pressure and rate needed but that seems to work well for a broad range of cams/valve trains.

VW type IV valves are almost identical to B20 valves and work with no problem. There's a performance parts/machine shop near me that stocks good quality economy SS valves from 36-50mm in even size increments. The also have Manley valves but they have a very narrow margin and I would only use them for racing. The same shop modifies new Scat hardened valve locks.

Isky push rods are chrome moly steel as are their retainers. They hold up very well to high rpm. The push rods are hollow tube 5/16" (.3125"). I like to enlarge and chamfer the holes in the head to facilitate oil return since the push rods are already larger than stock. You may need to restrict the oil to the rockers on engines that see consistently high rpm if you find oil pooling in the valve cover.

Lifters are one area you don't want to scrimp on. I once had a cheap Chevy style lifter seat fail and the push rod got stuck in the lifter which required removing the head at El Mirage dry lake bed and driving home on 3 cylinders.

Ian, Thanks again, what size should I machine the ID of of a restrictor to? I will be in touch with the two of you before I move forward with this head. The Type IV valves have the same lock to face of the valve dimensions?
 
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