Walbro Carburetor Question For The Experts

[Up A Creek]

Anyone have information on detailed specs for Walbro carburetors?

Specifically I'm wondering about the WJ 70 vs WJ 71.

I've seen the 70 listed as sized for 90 - 100 cc engines and the 71 for 100 to 120 cc engines.
However the Walbro site says all WJ carburetors are sized for 50 to 100 cc engines but no specifics. Which would rule out the 71 for larger than 100 cc.

Does the 71 have a larger venturi and jets? Is there any real difference between the 2?

 

[hotshot]

Anyone have information on detailed specs for Walbro carburetors?

Specifically I'm wondering about the WJ 70 vs WJ 71.

I do, but I’m not an expert. I know they have the same 18.25mm venturis & Husky used them both on the 394. Early carbs were WJ-39.

The only differences are the main nozzles (#86-793 vs #86-657 respectively), a throttle shaft washer, & the Lo/Hi mixture needles, every other part is the same.

You'd need to call VE Peterson in the great state of Ohio (419) 838-5911 to see which nozzle is larger/richer & thus set up for higher CFM.

 

[Up A Creek]

Knowing EPA restrictions I'd say the 70.
I can just drill out the jet if needed too.

Honestly I was mainly looking for a direction to start looking. I don't mind doing my own legwork. Tend to learn more that way too.
I really appreciate it.
Similar threads below also helped.

 

[Tomos770]

Look up here (regarding differences)...

https://web.archive.org/web/20051128211513/http://wem.walbro.com/walbro/family2.asp

 

[Up A Creek]

Yep, found that link.
It's somewhat helpful.

Thanks