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View Full Version : Do rockers increase horsepower???


elev8_dude
April 15th 2008, 10:21
Currently running Scat 1.25 rockers and its time for an upgrade. The reason for the upgrade is that the Scat rockers are worn out and I can't keep a valve adjustment for more than 2 months before it sounds like a diesel truck. If I'm going to upgrade I'd like to get some HP :).


For the upgrade, I'm looking at going with CB Performances:

Parts List:
(1643) Rocker Shaft
(1644) Rocker Arms Spacer Kit
(1665) Rhino 1.25 Rocker Arms Kit
(1642) 9mm Rhino Feet Kit

Engine Specs:
Vehicle: 1969 VW Beetle
Engine: 1915cc (Type 1)
Crankshaft: Forged Counter Weighted
Cam: C35
Compression: 8.5:1
Heads: 044 Super Mag CNC Round Port Heads w/42 x 37mm S/S valves, 94mm Bore Valves: 40x35
Scat: 1.25 Rockers
Carburetors: Dual 44 Webers (w/CB Performance Update Kit)

What do the German Look Guru's have to say???

wrenchnride247
April 15th 2008, 11:26
You need to have a cam that works with the ratio rockers. I believe the scat C35 is for 1:1 stock rockers. The 1.25's are for getting more lift from a STOCK cam. If you use them with anything else you can get the valve wear you are getting. ;) You will need new valve guides and springs at a minimum.

wrenchnride247
April 15th 2008, 11:31
Oh yeah, forgot to answer the question. Yes, ratio rockers can add HP, but to get longevity, they must be set-up correctly.

elev8_dude
April 15th 2008, 13:21
My mechanic had said that I needed 1.25. However the cam size you referenced seems very familiar. Thanks for the reply. I'll have to double check my original spec sheet to verify my stated cam size. Any further suggestions are appreciated.

Just wondering, how much more horse power could one gain with rocker upgrades (if done correctly) :)

wrenchnride247
April 15th 2008, 20:39
Well, about 5 to 10% hp depending on set-up. In the build spec sheet on your first post it said you have a C35, this has slightly less lift and duration compared to a engle 110 cam. (which is used with stock rocker ratio)