I just purchased an 81 RX7 ITA race car that's coming to Ontario to race at my home track Mosport just north east of Toronto. I will be porting the engine and adding a new intake and carb.

I have read the FAQ's on carbs but I'd like to get some actual feedback from any of you "road racers" that can tell me what has worked well for you.

Mosport is almost 3 miles in length and has hills, tight curves, fast curves and a very long fast straight (the ALMS P1's do 180mph +).

Thanks !!

 

Not sure what your rule limitations are for your Class. But if your looking at making good power bigger is better on most constant high RPM revving engines. If your on a tight budget look at a 55 DCO Side Draft they are cheap roughly $500.00 - $600.00 dollars new. If you have deep pockets and money is not a issue look at the Geers Engineering Terminator II carbs. Shaun is the owner of Geers Engineering, and you can find out more information about his carbs at http://www.geersengineering.com .
Plenty of fuel and a overall great product.

What kind of powerplant are you planning on putting together for your application?

Thanks
Albert

 

I will be starting with a N/A ported 12A for now......I'm looking at going turbo once I have the car sorted out for the track.

I've heard that some carbs will cut out on tight or fast curves.

 

The less expensive Holley carbs have a reputation for cutting out in turns, unless you get the right kind of float bowls. Venturi size cannot be changed on a Holley carb.

The carb you need depends on your engine. You cannot buy a carb made for a ported hi rpm race engine and expect it to work well on your little stock port motor; and vice-versa is also true.

The most flexible of the carbs are the Webers (or copies of Webers.) As your porting and rpm operating levels grow, then with a Weber you can change venturies and jets to get more hi rpm breathing.

 

For anything less than a full bridgeport (and maybe even then), I would recommend the Sterling carb: www.sterlingmetalworks.com

They provide the best low and mid-range performance (compared to two barrel carbs) and awesome wide open throttle high rpm power.

I only run autocross, but also daily drive mine. Couldn't be happier. Throttle control is excellent, and is especially noticable when racing in the rain. The link in my signature will take you to some of my videos, including an event in heavy rain. Until the track dried up, I had fast time of day. Check it out if you have the time.


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