83

I'm finally going Weber. LC Engineering Spiral Adapter is only for 22R. Is there a one-piece adapter out there for the 20R?

LC Engineering just said "when it starts to leak, replace the gaskets". Basically, they seal fine, but will leak eventually, before long, and I just need to replace the gaskets every time that happens.

Sorry if this has been talked about...every search I do just gives me giant threads to slog through, about every problem/solution except this.

gillesdetrail

iTrader: (1)

Good question, I thought lce made a spiral adapter for the 20r aswell, so that means I'm in the same boat as you. Everytime the subject comes up people say ''buy the spiral adapter'', but I too wonder if there is a way to use the redline adapter without it leaking. I'm thinking making your own gasket out of thicker and higher quality material would solve the problem, anyone try that?

enigmaT120

I have a different type of one-piece adaptor but I can't remember the brand name. But my motor is a 22R so it wouldn't help you.

I bought a sheet of 1/8" silicone gasket material off of Amazon for a few bucks and made a carb - adaptor gasket because I kept getting leaks there. I think my carb base may be defective, like warped or something. The gasket I made seems to be holding up. The material feels like rubber and is orange, and it was really easy to work with and make a new gasket from. I'm even using it to make an exhaust pipe gasket between my exhaust manifold and the pipe that replaced my catalytic converter, and it's not melting. Supposed to be good to 500 degrees F. It doesn't seem to be dissolving in the gas under the carb, which I'm worried about, but it's only been on a month or so. I left a piece in some gas for a couple of days with no discernible change before I used it for the carb.

Bingle

Well, not exactly the solution you're looking for, but you could go with this:
http://www.lceperformance.com/Downdr...-p/1032054.htm
More expensive than an adaptor, but I loved my dual plane on my 22 and you would likely get a minor gain in the top end with this manifold. Just a thought.

P.s. Just noticed that this IS NOT an Offy manifold, it's a Cannon. They made the manifold for my dcoe's and I've had no problems with it.

83

Ok, so I'm not crazy. Thanks.

Yeah, I'm thinking the only solution, other than fabricating my own plate, is an aftermarket intake manifold.

For now I'll just work with the Weber two piece adapter and see how things go.

I talked to technical support for LC Engineering on the phone, and he confirmed that they at least don't sell an adapter for a 20R, other than what comes with a Weber.

enigmaT120

This is the brand I have; the picture looks kind of like mine but my truck has a 22R:

http://www.ebay.com/itm/Trans-Dapt-2...-/331125857591

kawazx636

iTrader: (3)

^^^Looks legit. Part of the problem with the Weber 2 piece adapters is that the mating surfaces are completely smooth which doesn't allow for a good gasket bond. The one in the link that enigma posted looks like it has an abraded surface so that should help. It's kind of like the head to block mating surfaces - if it is completely smooth then you're more likely to have head gasket failure.

83

Thank you! I'm assuming it's been working well for you?

It was even $10 cheaper direct from Summit Racing.

enigmaT120

There's not much to go wrong with it, so long as the surfaces are flat -- and I checked mine before installing the studs. I think my problems are from the carb itself, but so far the silicone gasket seems to have corrected that. It's hard to diagnose a stalling/idle issue that never seems to manifest once I get the truck home in the shop.

83

In case anyone else looks at this thread, this part works great. http://www.summitracing.com/search/p...ht-in/1-750-in

So far. We just put it on with the Weber today. Everything runs great, and the engine is very quiet, and just a quick drive around a couple blocks, the Weber seems great!

The thing to be aware of is that this adapter is very tall. Your carb will be up about 2" higher than before. We had to move the throttle bar (not a cable on this truck) up. We used the top bolt hole as our new bottom hole, and drilled a new top hole. That and finding some spacers to raise the throttle return spring connection, and we were good.

It's no "spiral" adapter, but it sure works

JonnyBoy

I think the problem is less with the smoothness of the redline adapter as it is with the fact that the gasket mating surfaces aren't flat! The one I had seemed like it was just cast and then they checked it with a flat edge and called it good if it was within tolerances. The Spiral bore adapter I went to is also a 2 piece adapter, and has perfectly smooth mating surfaces. It's also aluminum, just like the redline adapter. The key is that the LCE adapter has had the mating surfaces machined to be perfectlt flat, so the gasket doesn't have to compress in some areas and swell in others to try to make a seal.

I even used a hard plastic "gasket" that would be reusable between the LCE adapter and the carburetor since I planned to remove the carb for some future mods, and no paper gasket between the hard plastic and the carb or the adapter. Never a leak.

I would probably still recommend the Trans Dapt adapter if you could, the height could actually help some with intake velocity, but I feel you could also take the redline adapters to a machine shop and have them machined perfectly flat to fix the leaking issue as well.

enigmaT120

Thanks for the update, 83. Glad it worked.