New Carb linkage for /4 engines- RAT "Accu-Link", Another approach for the solution of a long time issue. Options

[bandjoey]

With this low friction material and life turn it into a CLUTCH cable too! (IMG:style_emoticons/default/piratenanner.gif)

[SGB]

I'm ready too.

Did the roller cam setup ever get off the bench, Jake?

[DBCooper]

That linkage is exactly what's been on the BMW R-series oilhead boxers since at least 1993, so that may be where Porsche got the idea. It's good, but don't get your hopes too high. The cables do stretch and wear in, especially in the beginning when they're new, so they aren't totally hands-off. They'd eliminate it if they could, but BMW keeps TB syncing in the maintenance schedules for the life of their bikes.

I used the older BMW R-series airhead cables on a dune buggy in the 70's, copying a setup I'd seen on a car at Pismo. Those are a little different, a "Y" cable with a length adjuster in one leg of the "Y" for sync. Cheap, simple and worked great, but again it wasn't perfect.

By the way, there's a sync tool the BMW motorcycle guys use that's really cool, a lot better than any of the Unisyn or snail type flow gauges. It's an electronic vacuum comparison gauge called the TWIN MAX (link). Since it's electronic you can even dial the signal buffering up or down, to average and dampen the pulses and steady the needle. Quick, easy, and extremely accurate, kind of like electronic mercury sticks. More expensive than the Unisyn, but it really does the job.

(IMG:http://www.adventuremotogear.com/images/Twinmax2.jpg)

For dual IDF"s or DRLA's or four-cylinder motorcycle engines they say you just sync any two barrels, then use one as the standard and sync the remaining two to the first. I haven't tried it that way, but it works so well on the boxer twins that I don't doubt it a bit.

[EdwardBlume]

Super Cool! (IMG:style_emoticons/default/cheer.gif)

[jmill]

They do sell pre-stretched cable. They've been using it in the aircraft industry for years. It might be cost prohibitive. Heck what would we do if we didn't have to tweak stuff anyhow.

[scotty b]

How much load do you guys plan on putting on this cable ? I really don't see where stretching is a concern. It's not operating anything with a significant amount of tension on it like a clutch. Am I missing something ? (IMG:style_emoticons/default/confused24.gif)

[DBCooper]

I don't know. They've been making BMW boxer motorcycles forever, always with cable linkage. They've improved over the years but they still sync TB's and carbs on a regular basis. I'm sure theres's a BMW shop in your neighborhood, so ask them. Or poke around on a boxer message board. I think you'll find that old BMW boxers are just like the VW community, where syncing carbs and TB's is something that the newbies have to learn.

Cable's big advantage is that it's not affected by the engine's change in width from heat expansion. It's good in a lot of ways, and probably better than crossbar linkage, but it's not perfect.

[turnaround89]

it may not be perfect, but i think it will work a lot better than hex bar linkages...plus they look freaking AWESOME (IMG:style_emoticons/default/aktion035.gif) Much cleaner look in the engine bay with this setup than a hex bar.

[Joe Ricard]

Hex bar was designed by a retard.

[geniusanthony]

Worse yet is the chinese company that "copied" the hexbar poorly and made a so-so solution worse.

[crash914]

hmmm.. got a 94 oil head. got a twin max. I KNOW it will work to sync the throttle bodies.

The BMW throttles do go out of adjustment. but very small amount will bring them back in sync. usually less than 1/2 of a turn of the nut. The bike is just VERY sensitive to the sync. It only has 2 cylinders....

Keep the connecting cable short and it will be better....

[Jake Raby]

One of the biggest parts of this development has been the cable selection. Luckily the company we have paired with to make this happen has been using these same cables in a much more demanding throttle application (actuating 4 throttle bodies in a V8 app) since the late 1990s.

The cables are pre-stretched and I even have some kevlar woven cables that are not much more expensive and give the lightest throttle actuation. More than likely we'll have an upgrade to the Kevlar units from the standard cables for each kit.

Over time any cable will stretch a tad bit, BUT the beauty of the design I have came up with is the fact that one continous cable connects from an adjustable "union" box under the car all the way to the slave carburetor. What this means is you can make a single adjustment at the unon point and remove any slack in the cables.

I just returned from mky trip, I did pretty good bagging two hogs about 250 pounds each... I'll go back at the end of the month when the Moon isn't full and see what I can do.

Right now I am home sick with the flu trying to recover... The linkage should be fully tested by mid-spring 2010. I want to have all my personal cars swapped to it ASAP so we can continue evaluating it.

The first kit I will complete is the kit for the Type 1 application. There are 20X more of these vehicles on the road and we have the greatest demand for it at the present. After that the 914 kit will be completed. Since I am replacing the cable all the way to the pedal with my new arrangement all different vehicles will have a slightly altered kit.

[JmuRiz]

I'm ready too.

Did the roller cam setup ever get off the bench, Jake?

Good question, I've been waiting to hear about the EFI RollerCam 2270 with this linkage setup...could be the hot ticket for a street 914.

[Jake Raby]

Roller development is done for the 2270, I have been running a 2270 roller in my Wife's car for several months now with great success. It'll be getting this linkage very soon.

[JmuRiz]

Excellent!
Does it still have the small carbs on it, or has it gotten the EFI treatment?

[Jake Raby]

Just 40mm Dells.. Thats all it has needed and I know that EFI isn't as magical as most would like to believe :-)

Our new FI system will be installed this Spring. I have enjoyed keeping the car simple and I like carbs.

[turnaround89]

Glad to hear the testing is going well, can't wait till this goes on sale...I want one!!!!!

[Jake Raby]

Based on all the initial interest we have had I expect this to be one hell of a hot seller.. Which means we need to ensure that right out of the gate ALL the kits are 100%.

I just need to get these two cars outfitted...

[r_towle]

Consider making it totally hidden. That would certainly appeal to a select Type 1 crowd. Hidden being the main unit can be mounted out if sight and the individual cables can attach to the back of the carbs so none of the hardware is visible.

Cable adjustment at each carb with a simple lock nut is perfect for this setup...or some sort of adjustment that you can reach while syncing the carbs...

Rich

[eric914]

Yep!!!
A few people have made their own system that functions similarly; with cables.. Their was done a tad different, but still worked well.

But this is the first commercially available arrangement :-)

Now I wonder how long it'll be before the Chinese copy it???

Good luck, these look cool and would solve many of the problems with existing cross bar style linkages.

Good luck with that patent though as similar designs have been published in the past. Anything in public use for over 12 months even if it is not a comercial product can no longer be patented as it is considered public knowledge, even if it is your own design. You may be able to approach the patent by going after one or more unique features of your design though.