3T/2TG Hybrid AFR Troubles

[Celica_73]

Agreed they are a fairly cold plug that's why I'm not currently running them. I was running a Motorcraft AG42CU as advised by Goodmans. but just for the sake i had a set of near new BPR5EY in the shed from before I modified the Engine. Test discover a slightly different graph from the previous plug but still dipped below 10 on a WOT acceleration run the 4 time i did one. But the interesting part is the every slightly leaning before the drop. I'm no expert but thats telling me that the accelerator pump are not affecting this drop sure they maybe making it worse but not the cause. Next I've done some homework after the Turdinator state what shelldrake was running as his carby setup.

Granted this is for a weber carby but I'm guessing the basics for tuning a solex will be the same.

From http://www.racetep.com/webjettune.html

Choke Tube or Main Venturi size is the basis for everything in tuning DCOE, IDA and IDF carbs. If you get the Venturis wrong you will never get it running right. Too big and you will always have a flat spot that you cannot tune...Too small and it will always run rich and not make any power. If you have poor throttle response at low RPM

Also gave some tuning platforms for guides

Engine / Car.....Approximate HP.....Carb or Carbs........Starting Choke Tube Size
Toyota 22R...........140-150.............Dual 45 DCOE............34mm
Toyota 4AGE .......130-140.............Dual 40 DCOE............34mm

So going of this statement it's like Turdinator said the choke at 34mm

Also found
http://www.teglerizer.com/dcoe/webertune.htm
http://www.classicrallyclub.com.au/d..._DVAndrews.pdf
very informative about webers


So could this be my problem? or am I looking in heading in the wrong direction?

[Celica RA45]

try 145mains and 170 air correctors 57.5 slow runs and 36mm chokes if you can get them /and start from that
but if rodger can get you some 44mikunis that would be better as we use to use webber jets in the main holders

[Celica_73]

Rodger
I've received the parts today thank you very much. I'll give them a go on the weekend too hard to reactive the the pump at my place easier on dad's pit. I'll give them a go record some data and let you know the out come as soon as I can. I'm also trying to work out a way to post the graphs effectively on the forum so you can see the data first hand.

Celica RA45
That is similar to my current setup, only real difference is the Choke size. Yes I know this area in question as i now have the smaller pump nozzles I'll give them a try first and go from there. I'm thinking the next step is a bigger choke if this has no real luck.

Jason

[Celica RA45]

the last 2tg motors with the 260yama ha head ran 36mm chokes and 135 mains and 150 air correcters
and most 18rg came out with 34mm chokes
the early 2tg came out with 30mm chokes but werent using sleeves then hole size 45mm
next set up came out with 32mm chokes and had sleeves inside to keep them at 40mm
also how lumpy are your cams what duration and lift and also duration at 50 thou as you might not have enough carby and air emulsion tubes to tune them right for the cams ,next best thing would be a set of 44mikunis

[Celica_73]

Celica RA45
Cam specs

Camtech Grind 401A

Duration 293°
Duration @ 50 242°
Lift 372

A Fairly mid grind compared to other engine around this forum
I think it's a 260 head now fitted to the engine has a bit of head out done. Thanks for the advise

Jason
.

[Celica_73]

OK

With the 35 nozzles in the pumps the results are better but stills need work. mixtures getting down to 10. No real Flats spot but blows black smoke out the exhaust which is kinda expensive currently only getting 11L/100km mixed city and highway like to see that improved if I can.

I'm unable to come up with a simple method of showing the data so with this link
http://www.devtechnics.com/winlog.htm
This is the software used to view the data.

Data log files are here
http://www.steekr.com/n/50-17/share/...49df4ca04a31e/
in the zip file are the configuration files for the Winlogview to make life easier

Hope this works
Jason

[Celica_73]

Well an Update the problem is almost solved now. After much reading and playing around with jet and mapping the difference I've been able to achieve the following graphs. Note these are both the same jetting just in opposite directions along a long straight road near my place.

The carby setup currently stands at 34mm chokes, Main Jet 135, Main Air (modified 200) approx 140 (54 drill), Pilot 60 Pump jet 45 and middle hole






Opinions please on how to remove the dip at the start then she'll all be apples.

Thanks
Jason

[Rodger]

Map them against the revs and the length of the intake tract and you may find each peak and dip are resonate frequencies. The last couple of Race Magazines have had some interesting articals on Intact design with some interesting tables and graphs of revs verses air flow/volume.

The rich dip maybe at the transition from pilot to mains. Try the same run starting with lower throttle openings at 80k cruising and go WOT above 3500rpm to see what the graph looks like.

When on the track if that is your aim your running mostly above 4000rpm and light throttle going to WOT exiting the corners.

So has the off line hesitation and bogging disapeared? The most annoying issue on the street.

Regards

Rodger

[Celica_73]

Rodger

This car is a daily driven car (only car I have) and no play to put it on a track as long drive From Coffs Harbour to any track to start with. I tend to 'play' with setting on the weekend due that give enough time to revert what ever I've done so i can drive to work. The hesitation and bogging is still the but no where as bad as it use to be as that dip use to go off the scale!

As reguard to the rich dip in the AFR/ lambda just to clarify those runs were first crusing but about 60km before WOT. So the test your suggesting is to criuse at about 3500 rpm around 80km/h then open up to WOT to see the results. If thats the case i did that test a while a go the dip does go but only when above 4500 rpm. I'll try it this weekend with current setup. Just going off how the car is currently driving I'd say it will be a simular result.

Cheers for the input
Jason

[Rodger]

Ok you have done what I do.
But I not having any test or measurement gear to do the great work your producing perhaps means I worry less about the unknown.

I work on the principal of the way it drives and responds. As you say it is a daily driver so if it is cruising ok, not bogging down too bad (and some of it is cams, flywheel weight and timing) and not leaving you stranded in the middle of intersections then stick with it.

I know quiet a number of drivers that use way too much throttle on initial move, expecting their motors to respond. I much prefer to use less and wait for the revs to build a bit and then go wide open. As said before it is very different on the track as you are in the higher rev range already.

I must look at my AFRs on the very few dyno runs I have done and compare.

Regards

Rodger