A friend of mine Magnus is now on a Dynapack hub dyno. The engine has a very large streetport with 3 Weber 48IDAs!, very cool set up with short carbon fibre intakes. They have problems with the midrange being to lean 14-14-5 afr and on top 11 to 11-5 afr. E-tube is F11 with 210 main and 190 air jets. They will try F7 to get a more even fuel curve. Ignition L20 T10 on MSD 6s. Power is now 306 hp@9200 rpm! At wheels Approx 348 hp at cranc. I will come back with an update when the dyno session is over.

/Lasse

 

313 hp@9200 rpm final result. That's 355 cranc hp F7 tube with 190 main 180 air gave afr 13.0,unknown chokes. Timing was best at L 20 deg lost hp with L 22 deg split 5 deg gave a little bit more hp compared to 10 split. Lotus super seven wheigs only 1565 lb A real rocket on the road

/Lasse

 

A carbed 20b? Wow that is very interesting. Good numbers!

 

Got the torque numbers. 258 Nm@5800 rpm at wheels or approx 293 Nm at cranc. Pretty low numberas as i see it.

/Lasse

 

You got any pictures of this little beast?...

 

Side draft or down draft?

 

nice numbers, its interesting it didn't want much timing

 

IDA is a downdraft

 

F11 and f7/8 emulsion tubes suck! Try using f2 and f3 emulsion tubes with larger chokes- 45-46mm. Your going to need larger main jets and smaller air jets. Somewhere around 245-260 main and 100 to 130 air. Try that and let me know what kind of power you make. I'm pretty sure you will be surprised

 

Hope to have some pics this week.

/Lasse

 

Thanks for the tips! Hope to have the Lotus 7 for another dyno session later this year. The air horns are only 50 mm longMaybe he should try the 100 mm instead?

/Lasse

 

We recently rebuilt a stock 13b 6-port, that is in a Lotus/kit chassis. At a mere 160hp and 1200lbs it is VERY quick. 313rwhp 20b....... drool. Also insane.

 

 

Just heard from Magnus,the engine builder that the Webers only has 37 mm chokes! I would have tried more like 40-42 mm for even more hp

/Lasse