ESE's works engine tuner

[SwePatrick]

Raising the floor doesn´t change the duration

[peewee]

If you're planning to fit a watercooled spigot eventually, why not make one right away? You've still got a week to make a sketch.

You're joking, aren't you Peewee? Please tell me you're joking.
Methanol flow should be 16 cc per hp per minute. That's easy enough to check, but you must flow all relevant parts simultaneously, starting with the tank breather and certainly including the float valve. And if you add nitromethane, the flow requirement increases steeply, depending on the nitro percentage of course.

.

hi frits. I hope you didn't mistake me for some kind of 2t expert . its just a part time hobby, so the clearly obvious things aren't always so obvious. I should of welded a shell over the outer exh and transfer passages for water channels. then a water cooled exh spigot could be used. but as of now theres only water around the cyl bore. I did however show a sketch a few pages back of a water cooled spigot that ill use on my other engine since it has water channels around the full exh passage

few months ago I had a idea that may solve any fuel flow problems I might encounter, I still may carry on with this idea. I have a spare float bowl suited for a lectron and it has its own fuel inlet nipple and float valve system. problem is, its mostly meant for a engine with the carb angled out toward the left side like a Honda. my carb angles out to the opposite side, meaning the bowl is to wide and hits the kickstart area of the crankcase. although I had thought of cutting the bowl in half and welding the inlet and float valve setup on the opposite side. with two fuel inlets (one in the carb and one in the bowl) the engine wouldn't be so dependant on the large capacity of the current bowl with single inlet. I didn't want to use the current huge bowl but its picking up the slack of any deficiencies in the current system.

with two 5/16" fuel lines to the carb/bowl im sure it would be very near 7.5L per min flow , since my current single 5/16" line is near exactly 3.7L per min to the carb (without inline fuel filter installed). but how much fuel could pass through the two floats valves , im not sure yet but I plan to test the the carb valve soon. the carb float valve is 3.5mm diam but I cant recall the float valve size in the bowl.

[tdc211]

Raising the floor doesn´t change the duration

Maybe i should of said. Raising the floor at bdc.

[Muhr]

with two 5/16" fuel lines to the carb/bowl im sure it would be very near 7.5L per min flow , since my current single 5/16" line is near exactly 3.7L per min to the carb (without inline fuel filter installed). but how much fuel could pass through the two floats valves , im not sure yet but I plan to test the the carb valve soon. the carb float valve is 3.5mm diam but I cant recall the float valve size in the bowl.

That is serious power

7500/16 or did I miss something

[Jannem]

Anyone experimented with secondary air injection? Tested the bike in original condition with it connected and plugged. Plugged-> higher peak power, operational-> more power after the peak.
It would be simple to make a solenoid switched secondary air injection to heat up the pipe. Could run richer at top and still get the pipe to heat up. More power from the combustion itself, less heating of the cylinder and the pipe temp effect available by rpm switched solenoid directly into the pipe.

Thoughts?

[FastFred]

i think many people , including myself, have raised the floor to some extent. but ive never seen anyone raise it to the transfer tops.

Hi peewee what do you think about TZ350's posts on Team ESE's experiments with razing the exhaust port floor to TPO. I had a look at them, interesting.

a modified Suzuki RG50 engine with the exhaust port floor at TPO.

[wobbly]

Here are the STA numbers for a RSA/W 125 cylinder.
Note that these are the actual port numbers,and do not reflect that the Ex has a huge radius on the timing edge.
Thus in reality the actual Cd of the Ex would reflect that of the transfers,making both capable of the same power. Jan stated that any change in timing of the transfers ( up or down )
would loose power - showing that any increase in Blowdown by reducing the transfers /or visa versa upset the delicate flow balance.
Note also Jan stated that lifting the Ex port floor and reducing the duct volume only worked once the Blowdown had been optimized for best power.

[dutchpower]

Why lifting the exh. port floor on 50 cc give less power Wobbly

[wobbly]

Having an engine with 27% more transfer STA than the Blowdown is so weird I doubt that it would make any power at all, no matter what was done with the Exhaust duct .

[Grumph]

Having an engine with 27% more transfer STA than the Blowdown is so weird I doubt that it would make any power at all, no matter what was done with the Exhaust duct .

What about the case where there's a ring of exhausts above the transfers ? Does sheer port area compensate for blowdown time ?

[wobbly]

The STA concept was developed long ago and has been refined into a user friendly tool that accurately predicts
the power capability of ports that we would regard now as possessing a "normal" 2T scavenging process.
I, and the current scavenging models as are used in code like EngMod, have no way of even beginning to predict what would happen with
weird arse configurations that dont represent the SOTA as we know it.
Though Neels has recently worked on introducing code that accurately models Mr Rygers ( Lucs ) so far very wet dream.

[peewee]

Hi peewee what do you think about TZ350's posts on Team ESE's experiments with razing the exhaust port floor to TPO. I had a look at them, interesting.

I didn't know he had already raised the floor so high. he is the first that I know to do it. ive never seen the ese experiments. is it another section around here ?

[peewee]

Having an engine with 27% more transfer STA than the Blowdown is so weird I doubt that it would make any power at all, no matter what was done with the Exhaust duct .

usually its just the opposite with the engines ive seen. the transfer sta is far to short with little chance of making any improvements without a welding machine and 10lb of filler rod. mainly from terrible stud spacing is to blame I think. the late model ktm dirtbike engines seem to be pretty good however

[TZ350]

ive never seen the ese experiments. is it another section around here ?

This thread started out of Team ESE's efforts to learn about and develop their bikes.

But it is by far and away the excellent and interesting contributions from lots of other people that have made this thread such a good 2T tuning resource.

I am not sure that the Team ESE exhaust port floor at TPO experiments are all that conclusive, interesting but not conclusive.

To follow any link back to its origins, just click on the little blue arrow thing after the quoted persons name.

Blue = Exhaust dam level with TPO. Red = Dam opening 4 deg after TPO.

Exhaust port dam ... Blue = Standard "A" ports, Red = Widened "A" ports. Useful improvement in bottom end power.

[Grumph]

The STA concept was developed long ago and has been refined into a user friendly tool that accurately predicts
the power capability of ports that we would regard now as possessing a "normal" 2T scavenging process.
I, and the current scavenging models as are used in code like EngMod, have no way of even beginning to predict what would happen with
weird arse configurations that dont represent the SOTA as we know it.

That makes two of us, LOL. It's been discussed here and I thought you may have an opinion.

Probably a better use of time to refine the already known.