Extending the reversion read with the Wego, when a EFI run is done with the Wego, it is important to slow down with the brake and not let the throttle off quickly, the Wego samples AFR in every area over and over taking high and low readings and blends them together in that area of the map. If you are building a EFI map and running on cruise area for several miles and recording to target that area, a couple of throttle roll offs coming back thru that area will blend the high reversion AFR into the good cruise AFR and throw the final AFR off.
We are just seeing the reversion graph live with a carb, all the peaks and valley's are jumping out where the Wego blends it together to produce a number for EFI for viewing in a map form, you make adjustments off the number provided by the Wego3, it is advanced for EFI just hard as hell to use on a carb without the time scale feature
If you guys think my fatcat is causing the reversion what do you think of an rb racing pro stock 2-1? I have one here that used to be on it. I replaced it because it was L.A.F., sounded real nice just very loud. Not too bad riding around but on the highway its like having a nascar next to you. I have a baffle for it that rb sells, it does take a little of the edge off but still loud. They claim their collector design keeps reversion down and improves scavenging. It has an o2 sensor port in the front pipe and it 1 3/4 inch diameter. I could change it out in no time, let me know what you think.
Your reversion really isn't affecting anything except a peaky graph, If it is popping on decel or popping out the intake when throttling off a decel then a problem is present. Exhausts are different designs to control torque dip at 2500-3000, power numbers at WOT. If you want to change to the RB pipe and run again it should level out some of peaks of the graph but Hotrod's power numbers wasn't as good with his RB, he should be along to fill in. Personally I think your carb is set good right now by the numbers I showed in the spread out graphs
Bagger is correct, None the pipes are any good for low end performance. That is why you see a lot of jumping in the afr's. The best pipes I've had on the dyno were my old python III staggered duals. They really were a good all around pipe Real good sound, loud but not LSR loud.... I only lost a couple of hp and torque on the top but the bottom was nice. The 2-1's that we are using (RB, Fatcat) on smaller inch motors do not work as well under 3k but around 3200 rpm they are monsters. I will try to find a dyno sheet I have showing the two. On the Pythons Scott actually put a 1/4" bolt loaded up with 4 nuts an inch inside the end of the pipe to decrease the reversion. In real life we hardly run consistently over 5k (unless we're racing or sutton) You really do need to pay close attention to 2800 and up through the midrange to wot. Just like bagger said.
And by the way, I don't think it would hurt to try the RB pipe with the Baffle..... Most of they're pipes are made according to your engine specs. Don't know for sure but why else would they ask about your build when ordering?
When I ordered my RB pipe, the bike was all stock except for the mikuni. I dont know if that would make a difference or not. I do have some decel popping out the exhaust, not like gun shots, but there is some popping. As far as popping or coughing back through the carb, no problem there. I guess it cant hurt to try my RB pipe.....I'll be back.
One other thing you need to do is check the intake seals at the head for vacuum leaks. as rich as you are on the slow jet I wouldn't think there would be popping out the exhaust. All though at times I have noticed how lean it was under 2k.
The seals I used on the intake were the cometic ones that came with the gasket kit. They did look a little on the thin side, Iv'e always had better luck with the blue James seals in the past that were a tiny bit thicker. I got about 3 or 4 sets of those. Those cometic seals been on my mind since I put that together. I think that will be my weekend project.
And a question for you guys I had asked before, what do you think of those heavy breather forward facing style air cleaners? Good or no good? Thank again guys for all your help, I'm working on it.
Actually, now that you have a wego, take off the a/c totally and take a small ride and monitor the digital read out to see the difference. Take 4th up to cruise @2800 rpm and see how it compares to other runs. You should see a big difference. Don't leave it like that though. Not good. It should be quite lean....
Last edited by 98hotrodfatboy; 02-22-2017 at 11:43 AM.
If I take my air cleaner off the carb will fall off. I have the mikuni air cleaner that clamps directly on to the carb with brackets that go to the breather bolts
02-20-2017, 07:47 PM
