OK to use 1.4 rockers with stock cam?

[Martin S.]

My friend wanted to slap together an engine that is solid with counter weighted crank etc., but has a stock cam. He might bolt on a set of Kads or 40 Dells. I thought he should get a cheap set of 1.4 rockers to add at least some more lift for now. Later a cam can be added, but is there any problem running 1.4 rockers with the stock cam? A set of these are cheap enough.. https://www.cip1.ca/ProductDetails.asp?ProductCode=C13-21-2164

[Zach Gomulka]

No problem at all, I ran 1.4's with a stock cam on my last engine. Lifts around .420". I recommend HD single springs and pushrods as well though.

[Erlend / bug66]

Stock pushrods and HD singles on my first "built" engine.

Worked perfect!

[Martin S.]

Great! Thanks, just gotta remember to order lash caps too.

[BeetleBug]

It might work fine to change the ratio in order to achieve more lift but I'm not so sure it will give you more HP with original heads. The channels are so poor that they have done their job at low lift. You have to do a job with the ports in order to utilize the higher lift.

Best rgs
BB

[Torben Alstrup]

It will aid a little in better hp numbers, along with extending the rpm range upwards with about 3-400 rpm. The torque down low will suffer unless DCR is compensated with more static compression.

T

[BeetleBug]

Thanks Torben, it is always interesting when you share your knowledge!

From a Swedish page:

Original heads and 25" water pillar, 35mm intake and 32mm exhaust valves;

LIFT:
2mm 32,8cfm
4mm 61,6cfm
6mm 83,8cfm
8mm 89,0cfm
10mm 93.1cfm
12mm 97,2cfm

See the excellent write up here: http://boxerville.se/forum/viewtopic.php?id=10359 It is in Swedish but you can see the pictures of the different steps he did followed by flow testing in order to measure the effect.

Best rgs
BB

[dragvw2180]

 I would look very closely at the valve retainer to valve guide clearance with the 1.4's and like has mentioned add heavier springs. When I tried it on my original bug ( in 1975)  I couldn't tell much difference performance wise . Now if you want some fun for a little while, add nitros to the stock engine, LOL

[Jens-Ole]

I had to make shorter push rods for my supercharged twinport "34hp" engine project with a stock cam.
So I guess you should too, but otherwise everything turns nice and with a little porting everything helps the stock engine