16 HP heads on 18 HP Vanguard

[Tom12254]

Hello everyone, so I have a 18HP vanguard in my Yamaha G2 with the steel stamped rockers. I've been searching ebay and found some 16HP vanguard heads with the aluminum rockers. I've read the 16 heads will fit on the 18 motor is this correct? Or could I possibly just swap the aluminum rockers into my 18hp heads and ditch the stamped steel rockers?

[slonomo]

I could be wrong, but I believe the 14, 16, and 18 hp heads are all the same. I believe the hardware is different on the aluminum rockers so you need to use the heads that came with them. Honestly, the stamped steel rockers are fine for most purposes, even speed builds, unless you are looking for rpm past 6k. The aluminum rockers are stronger than the steel, but not by much, and there's no performance difference between the two. If you are getting a good deal on the alum rocker heads, get them. If they are expensive, you could spend your money on better parts that get a performance gain instead. Just my thoughts.

[slonomo]

Here's a thread I started about this subject, good info here

https://www.buggiesgonewild.com/showthread.php?t=100248

[Tom12254]

Originally Posted by slonomo

I could be wrong, but I believe the 14, 16, and 18 hp heads are all the same. I believe the hardware is different on the aluminum rockers so you need to use the heads that came with them. Honestly, the stamped steel rockers are fine for most purposes, even speed builds, unless you are looking for rpm past 6k. The aluminum rockers are stronger than the steel, but not by much, and there's no performance difference between the two. If you are getting a good deal on the alum rocker heads, get them. If they are expensive, you could spend your money on better parts that get a performance gain instead. Just my thoughts.

That's what I've heard too, the stamped steel rockers can probably handle what I'm doing I'm just reving up to 5kRPM for short "speed runs" lol. I just purchased the Cheetah cam from CPP so now I'll have the rev kit, cheetah cam, timing advance key, so I figured why not throw the aluminum rockers on too. They were $99 for the set of heads with aluminum rockers so I figured that was a pretty good price from what I've seen them sell for in the past! I MIGHT go for the ARC billet flywheel too but I'm undecided on that yet.. I was looking on ECs website and noticed they sell dual valve springs and behive valve springs for the vanguard engines.. Would either of these options work to eliminate the need for the valve shims in the rev kit from CPP when running the Cheetah cam?

[slonomo]

Yes upgraded valvesprings will work instead of the shims. You have to be careful with valvespring tension, they can cause damage to the rocker studs, sometimes pull out. If you buy from a dealer, call them and ask them what they recommend, often times these dealers build engines too and know from experience what will work with your situation.