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Thu Feb 02, 2012 6:05 am

I am in the process of building a 1776cc engine for my 67 bug. It has a 110 cam in it. I'm running dual kadrons that I have changed the jets in. EMPI 041 heads. I am wondering what rockers would be appropriate to use. I'm really in between using 1.1:1 or 1.25:1. My only concern is low end torque. I'll be using the car mainly for cruising, but may take it to the strip once in a while.

Thu Feb 02, 2012 6:16 am

If you need to buy new/better rockers then just move up to the 1.25's the difference is almost negligable. You may pick up a few Lb's of torque.
I would at least use solid shafts and stock rockers with 911 adjusters.

Thu Feb 02, 2012 9:50 am

I would go with the 1.25 rockers that have the adjuster on the pushrod end,there closer to 1.3 ratio(1.33 for the 2 sets I have). as far as the 911 adjusters on oe type rockers,the ones I have seen are pure junk,yes there the china ones.are there any other's??just sayen.

Thu Feb 02, 2012 11:41 am

Rick, if you are going to run 1.25's with a W110 I suggest you run dual valve springs. HD singles will be marginal on valve control and reliability. Are your empi 041 heads running the mis-matched 39 x 32mm valves with stock ports (no port work)? If so I'd skip the 1.25's as any gain would be small at best. The bigger the cam and the better the heads, the more the 1.25's will have an effect.

If you buy 911 adjusters, BUY 911 ADJUSTERS. Most everything else is a cheap copy. Buy once, cry once and have it for life for every engine you build. Kind of like Udo Becker lifters. Expensive but worth saving for. My 2 cents.

Thu Feb 02, 2012 1:56 pm

^^^What my friend Darth said^^^

Mon Feb 06, 2012 1:11 pm

I am running dual valve springs. The question of which rocker arms to use is really a question that deals with the power band. I do want some top end performance, my fear is that the low end is going to suffer with the 1.25 rockers. I know that it will increase the amount of horsepower, but I don't want it to run terribly whenever just cruising the street.

Mon Feb 06, 2012 1:50 pm

Again, I ask you, what size valves are in your heads? The 39 x 32mm that come in the 041 were designed as a smog head. The smaller exhaust valve increases heat in the head and was supposed to reduce emissions. Not a good idea for a performance head.

On the other hand, replace your exhaust valves with 35.5mm and do some mild port work and you'll have something to work a little better with your cam, engine size and better rockers. Or better yet, get some good heads, JMO.

I believe you are splitting hairs here with the 1.25's. Fact is you probably won't be able to tell any difference at all in low end torque (which should improve a bit) nor in top end HP. You could measure it on a dyno but from inside the car doubt you'd feel a thing. If you had a set of well ported 40 x 35.5mm heads with a W120 cam and you were contemplating adding the 1.25's, then you'd have something there.

Add the 1.25's if you like, I'd save my money, you won't lose any torque or HP......but you won't gain something that will make you say "Wow, I'm glad I added those 1.25"s" either. And they won't make your engine run rougher or be less smooth when cruising.

Mon Feb 06, 2012 2:01 pm

if you haven't ANY rockers at all, it makes sense to consider 1.25s. But if you have 1.1s I don't consider 1.25s much of an upgrade, the cost/benefit is astronomically expensive, because you need new push rods too.

Mon Feb 06, 2012 2:11 pm

- Empi 041´s have 39/35 mm valves. Also known as "GO3" heads.
- What John said. And then, - it really depends on the rest of the engine whether you will gain much. if the heads are as out of the box it most likely wouldnt change much. If they are ported with small volume ports you would get some upper end power.
Personally I would NEVER run 1,25´s on a W110 cam. But that´s me.

T

Mon Feb 06, 2012 6:33 pm

Yes that's right the empi 041 heads have 39/35mm stainless steel valves. Sorry if I hadn't answered the question. John I have stock style 1.1 rockers with the old style clips. From what I have heard about the clips it is better to go with the newer style rockers. So I figured why not buy 1.25s.
John as far as pushrods are concerned I was under the impression that pushrod length would be the same.

Mon Feb 06, 2012 6:46 pm

your impression is wrong Rick. A lot of shops either

don't know
or
know, but don't tell you

in either case it's not a good thing.

rickb67 wrote: Yes that's right the empi 041 heads have 39/35mm stainless steel valves. Sorry if I hadn't answered the question. John I have stock style 1.1 rockers with the old style clips. From what I have heard about the clips it is better to go with the newer style rockers. So I figured why not buy 1.25s.
John as far as pushrods are concerned I was under the impression that pushrod length would be the same.

Mon Feb 06, 2012 6:58 pm

I really appreciate the info. Could I use the original style rockers or would you switch to the newer style 1.1s. For what I am using the car for I'm not sure that I want to mess around too much with rocker geometry. I can, but does it really make sense?

Mon Feb 06, 2012 7:13 pm

I guess that my next question would be if I do have to change the geometry anyway, why not go with the 1.4s?

Mon Feb 06, 2012 7:15 pm

your rockers have to be compatible with the heads and cam.

You can NOT run rockers larger than 1.25s with the W-110 cam. If you want to run 1.4s, you need a different camshaft.

Your money is far better spent ditching the Kadrons for some dual 40 IDFs, and keeping the 110 cam and 1.1 rockers.

Mon Feb 06, 2012 7:20 pm

[email protected] wrote: your rockers have to be compatible with the heads and cam.

You can NOT run rockers larger than 1.25s with the W-110 cam. If you want to run 1.4s, you need a different camshaft.

Your money is far better spent ditching the Kadrons for some dual 40 IDFs, and keeping the 110 cam and 1.1 rockers. and why is that?

Mon Feb 06, 2012 8:07 pm

not sure what you are asking, but Kadrons are horrible excuses for carburetors.

Mon Feb 06, 2012 9:32 pm

110&not more than 125's

Mon Feb 06, 2012 9:49 pm

Mark, you need to speak in English and complete sentences if you want someone to have a clue what you are asking.

mark tucker wrote: 110&not more than 125's

Tue Feb 07, 2012 8:20 am

mark tucker wrote: 110&not more than 125's

Because Jack Engle himself said so. Do you get it now. The man that built the part said you can not use 1.4 rockers with his part.

Tue May 01, 2012 6:48 pm

Just asking a question;

If he went with 1.25 rockers, would he be able to adjust the rocker geometry with shims beneath the rocker assembly instead of changing the pushrod length?