Why do I want high lift rockers with a stock cam?
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1:25 to 1 You'll need the shims and have to probably cut push rods to length. https://www.ebay.com/itm/New-V...7:g:L4IAAOxyOM5RapdU
Alan,
Thank you, I was unclear, I was wondering what the advantages of such a setup are.
The higher ratio rocker arms increase the distance the valves move into the cylinder allowing more fuel:air to come in and exhaust to go out. This increases the horsepower. It's like getting a more aggressive cam even when you keep the standard one.
Michael,
Thank you, and I guess it can be done in the car.
Robert,
For me part of the fun getting a VW powered car is the very inexpensive parts and interesting upgrades that one can do in ones garage. As soon as my car is out of warranty I plan on having some cheap fun. Cheers.
Richard
"Very inexpensive parts" he says. The madness has yet to take effect with our new Richard here.
Mike whispers "Panchito heads"
Use 1.4:1 rockers- there isn't enough of a difference with the 1.25's to warrant spending the extra money and a stock engine with dual carbs and a header will respond well to the extra lift and duration. Al
I have been running 1.3:1 for several years with the stock cam 1915cc. I also run dual Weber idf 40's. There is a noticeable increase in performance. I would say it was money well spent for me.
@Michael Pickett posted:Mike whispers "Panchito heads"
Not a good choice on a stock cammed 1600...
Agree that using 1:25 rockers alone will not show a big difference, combined with decent carbs, exhaust, distributor / ignition.. having those items set up properly will get you some noticeable performance.
Here's the thing: rockers are all over the map. Some guys have measured generic eBay "1.25" rockers and found them to lift almost 1.4:1. I bought a set of CB's "1.4" rockers that measured out at 1.47:1.
The stock VW cam is split lift and duration (the intake is different than the exhaust). The specs I'm finding claim a stock cam lifts .297 on the intake at the cam.
If Kaddie Shack's "1.4" rockers really did lift 1.4:1, they'd be bumping the intake valve .4158", which seems to be in the range for single valve-springs. If they measure out to 1.47:1 (like mine do), they'd lift the valve .4366".
The stock cam's duration is 224*/228* and 210*/215* at .050" (intake/exhaust), which is very, very mild.
It's an interesting question. According to a cylinder head chart over on TheSamba, a VW 043 dual-port cylinder head flows 109 cfm at .400" lift and 117 cfm at .500" lift. According to the Wallace Racing cfm/hp calculator, the stock heads should support 109 hp at .400" of lift. This is clearly poppycock, but it makes me tend to believe @ALB's link.
I'd use 1.4s with a stock cam and heads. What's the worst thing that can happen? Broken valvesprings are cheap and pretty easy to change.
@R Thorpe posted:Robert,
For me part of the fun getting a VW powered car is the very inexpensive parts and interesting upgrades that one can do in ones garage. As soon as my car is out of warranty I plan on having some cheap fun. Cheers.
Richard
Sure thing, Rich. Have you looked at the Weddle Industries webpage lately? 
FWIW, I got a rebuilt trans for my Manx from a place in Vegas for $600+exchange in ~2003. The same price as the 1-2 shaft I wanted for a custom gear ratio.
Some things are expensive but for the most part things compared to Porsche are cheap. 20 years ago I had a 3.2 “Max Moritz” made for my 911 it cost 30k then, god knows how much it would cost today. You can get a nice turnkey VW based engine for under 10 K that’s cheap
Regarding cost-- before I bought my first speedster, I bought a "Hot VWs" magazine and thumbed through the ads, thinking I'd found the perfect hobby for a cost conscious and sensible gearhead.
The parts that get you to 80 hp are ridiculously cheap... but they are gateway drugs-- because really, how can a God-fearing car guy not feel like a wannabe-weenie when he's piloting a plastic clown-car with an 80 hp roto-tiller engine that says, "SPEEDSTER" right there on the side of it? It feels ridiculous.
That's the point where the whole thing starts unraveling. "More" is revealed to be more. 80 hp becomes 100. 100 becomes 130, and after 130 or so, each and every pony comes at about a $50 premium. After 150 hp, that $50 becomes $100, and after 180, the bell curve goes straight up. You stop talking about how cheap these cars are when you realize that the guy with the '69 Camaro with the LS crate-motor spent a quarter the money for 4x the power.
But you are in too deep now to climb back out. Money gets shoveled into the boilers of progress. Receipts are hidden from less understanding spouses. Accurate accounting becomes irritating. Parts are acquired, installed, and discarded without fanfare. That friendly 1776 grows into a serious 2110 before it becomes a barely-idling 2387 with a dry-sump and 1-3/4" headers. Your browser history contains searches for "Type 1 nitrous oxide systems" and "heat management in turbocharged air-cooled engines" (if you forget to clear your cookies).
You talk your car down at cars and coffee or down at the gas station to avoid having to say out loud what all this stuff costs. If you say it-- it becomes real money, and not the Monopoly money you've been spending. You burn precious vacation time driving across several time-zones to get together with people who don't need to have the entire thing explained to them. You enjoy their company, much in the way junkies tend to congregate at crackhouses. Since you are out there anyhow, you look at their cars. You can talk freely about crank-fired this and billet-milled that. You make the mistake of driving somebody's Raby T4 car and think, "I don't know-- $35K isn't so much for an engine, is it?" You drive back home wondering how to install a lift in the garage.
You delay retirement so you can keep going. You get beat off a light by some kid in a 5.0 Mustang, and you seethe. You get on Pat Downs' waiting list. You call Carey Hines while your wife is at book club and ask him to quote a coupe (you know, for a second car). Dean Polopolus' 911/4 is something you know the cost of. You go to the JP Motorsports page and think about a Type 1 with 4" cylinders.
Yeah. It's a cheap hobby
in the beginning.
I figure I've spent around $1K at the Ace Hardware by my storage unit/shop in the last three years on nothing but SS hardware and drills/taps/dies.
Speaking of cost:
Whats $3K, adjusted for inflation, given most Speedsters are going for close to half a mil at auction?
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@Alan Merklin posted:Agree that using 1:25 rockers alone will not show a big difference, combined with decent carbs, exhaust, distributor / ignition.. having those items set up properly will get you some noticeable performance.
I'm just saying, Alan, that IF you're going to go to the expense of adding ratio rocker arms to a stock cammed engine, you'll get better bang for your buck with the 1.4's. You probably wouldn't feel much of a difference using the 1.25's
"You enjoy their company, much in the way junkies tend to congregate at crackhouses."
I lol'd so hard I spit out my crack pipe & lit my crotch on fire.