2000 GTI swapping carburetors

[pbob42]

had this is in the wrong forum

Last year was a challenge with several 717s biting the dust. So I have 3 motors, one I rebuilt, from a 2000 GTI. Put a rebuilt dual carb on it, 1.2 needles and seats, don't think it was the original carb. Now, the ski ski starts and idles great but bogs down when I get over 1/3 throttle. I am believing I am getting too much fuel.

Now, on my 63' olds, if I want to go faster, I put a new manifold and carburetor on it, instant speed.

I am getting the feeling that these 2-cycles don't work that way.

What is the deal with these motors and these carbs I have laying around? do they mix and match, or is there more to it than that?

Any help would be appreciated.

 

[pbob42]

looks like the original is a mikuni 40I single carb.

 

[mikidymac]

No, they don't mix and match.
You can run a single carb and manifold or a dual carb and manifold on a 720 and they both will make 85HP.

The dual carb 720's are a BN38i and the single carb are a BN40i so you can't just take a 38 and put it on the single carb manifold and run it.

 

[pbob42]

Well, I changed the manifolds, and have them installed. They are just not performing that well. The GTI motor mount brackets are such a pain to get around, I have to about pull the motor out to get to the manifold to change back. I think I am getting too much gas and need to re-jet these to get them to work right. Ski starts and idles good, Once I get over about a 1/3 of the throttle it just boggs down. Pop-off is like 27lbs.

seats are 1.2. Maybe I am missing something else, but any suggestions on a re-jet? I am thinking I need to go smaller. Haven't done a re-jet before, looks pretty easy, but I don't know how big of a change to make. Love to hit this without a lot of trial and error.

The high-speed adjuster on these are all the way closed, I assume to keep you from running lean. If I reduce the hi speed jet, I am assuming I will to bring that high-speed adjuster more into play.

 

[mikidymac]

There is no reason to rejet these if they came off a 720.