21 Hydro engines - What brand is your choice?

[Jorgen Andersson]

Hello

What 21 Hydro engine brand/version is working best for you in 6 lap heatracing?

Please comment things like:

* Torque

* Top end rpm

* Drivability

* Plug life

* User friendly

* Others

Thanks

Jorgen

 

[Duck899]

Hello

What 21 Hydro engine brand/version is working best for you in 6 lap heatracing?

Please comment things like:

* Torque

* Top end rpm

* Drivability

* Plug life

* User friendly

* Others

Thanks

Jorgen

Jorgen, so far for me the Nova-rossi 5 port is working best. Good top end with an Andy brown 1445 with 3.3" cup. Woods S pipe. Plugs last all day unless you get on the needle too much. Currently running a JAE 21. I also have another JAE with an AA21 that I will be experimenting with in the next 2 weeks.

 

[gil sonsino]

CMB valvola Mac open pipe 1445 cup 3,5 and 1450(46mm cup 3,3) H7 and CMB 21 vac under testing.

Gill

 

[Tim_Duggan]

NR TOP 35PLUSM with A.R.T. head and SPP RS21 pipe & sleeve lowered a little. ODO77T Plug lasts all day - in fact I'm yet to blow one. Window for needle setting is broad - not touchy at all. Runs well still sounding rich with a shiny plug.

A whisker under 30KRPM on pipe with good torque, Launched & Pulled a full diameter H7 with 3.75" with 50% nitro fuel nicely.

Dislikes;

180 degree header - original sleeve timing numbers were too high - cooling jacket water passage is huge - carb is not too good in stock form - odd size bearings.