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Re: GT kit Dyno graphs

Posted: Mon Dec 21, 2015 7:42 pm
by eden
Great thing about this dyno too is that as its loaded it can run at any rpm or speed and test part throttle A/F, my GT had a lean spot just before the exhaust comes in which I dialled out last month on there with the ignition curve. no use changing the jetting as at higher or lower rpm at same throttle position it was fine.
Very hard or impossible to do that on an inertia dyno.

Re: GT kit Dyno graphs

Posted: Mon Dec 21, 2015 7:54 pm
by Darrell Taylor
id recheck that ,,,, a lean spot(before coming onto pipe you encounter a double rich mixture that fools the lambda with a splutter/misfire that reads as lean but is actually rich,,,does same if main jet is grossly rich and misfires it reads as lean.... fools you for a few months as it did me till you start to understand whats happening) ,the roll on is critical in that area too as can misread with different roll on techniques did you run with a t.p.s. during the load cell runs ? how was that monitored

Re: GT kit Dyno graphs

Posted: Mon Dec 21, 2015 7:55 pm
by Darrell Taylor
eden wrote:
Darrell Taylor wrote:i cant get them to rev past 5000 rpm on 10.5-1 bosch lambda readings or travel more than a few miles without oiling a plug ???
odd! :?

tbh my 250 on Saturday was off the scale rich as his scale begins at 10-1 lol
Martins twin pipe targa was very lean on one side up around 15-1 :( hes lucky he can test each carb unlike normal targas with one pipe.
what did targa do ?

Re: GT kit Dyno graphs

Posted: Mon Dec 21, 2015 9:29 pm
by eden
Darrell Taylor wrote:
eden wrote:
Darrell Taylor wrote:i cant get them to rev past 5000 rpm on 10.5-1 bosch lambda readings or travel more than a few miles without oiling a plug ???
odd! :?

tbh my 250 on Saturday was off the scale rich as his scale begins at 10-1 lol
Martins twin pipe targa was very lean on one side up around 15-1 :( hes lucky he can test each carb unlike normal targas with one pipe.
what did targa do ?
1.5 bhp more than mine and 2 ft/lb less. Don't know if you much about that targa or not but it's no normal targa ;)


So are you up for bringing one of those gt 186's down to this dyno?

Re: GT kit Dyno graphs

Posted: Mon Dec 21, 2015 9:33 pm
by eden
Darrell Taylor wrote:id recheck that ,,,, a lean spot(before coming onto pipe you encounter a double rich mixture that fools the lambda with a splutter/misfire that reads as lean but is actually rich,,,does same if main jet is grossly rich and misfires it reads as lean.... fools you for a few months as it did me till you start to understand whats happening) ,the roll on is critical in that area too as can misread with different roll on techniques did you run with a t.p.s. during the load cell runs ? how was that monitored
Not splutter or misfire. I'm talking about holding it under load at that rpm not accelerating through it.

Re: GT kit Dyno graphs

Posted: Mon Dec 21, 2015 9:51 pm
by hendy
Darrell Taylor wrote: ,these graphs are just the small block motors -gt186 kits ive tuned running 25mm carbs on safe afr of 12-1 for touring ,correction factors are displayed and are as can be seen low reading on these runs .
Are any of these through the airbox with a clubman? Impressive if they're not, but even more so if they are!

Re: GT kit Dyno graphs

Posted: Mon Dec 21, 2015 9:55 pm
by Darrell Taylor
so just below 31 for martins targa it read the same on ian embertons at york rally i believe ?
and yours 29.5 same again on ians dynojet at lincoln

Re: GT kit Dyno graphs

Posted: Mon Dec 21, 2015 10:03 pm
by Darrell Taylor
hendy wrote:
Darrell Taylor wrote: ,these graphs are just the small block motors -gt186 kits ive tuned running 25mm carbs on safe afr of 12-1 for touring ,correction factors are displayed and are as can be seen low reading on these runs .
Are any of these through the airbox with a clubman? Impressive if they're not, but even more so if they are!

no ,,youll not get that result on a clubman 22 tops on a well sorted 186
not through the airbox either
yours is held back by the ancillotti,ive done the test and do restrict them ,,go for gori or bgm clubman if you like that style or put an expansion on it to release full potential ,,carb run it on a breathe sweet set up for best results

Re: GT kit Dyno graphs

Posted: Mon Dec 21, 2015 10:15 pm
by eden
Darrell Taylor wrote:so just below 31 for martins targa it read the same on ian embertons at york rally i believe ?
and yours 29.5 same again on ians dynojet at lincoln
Not sure what if anything Martin has done to his since then but mines changed a lot with changed port timings and head design.

Its no where near the same as it was then, I've gone longer on my gearing due to the noticeable difference, which just proves my point that different dynos are not comparable.
Come on darrel bring that gt 186 to the dyno down here so we can use it as a benchmark :)
No harm in that.

Re: GT kit Dyno graphs

Posted: Mon Dec 21, 2015 10:32 pm
by Darrell Taylor
ive not got gt here its all done, customer taken it a month ago, his scoot is being painted be feb march before he is on the road ,done a 25mm and clubman one at 21/22 from memory thats to be fitted over winter by him ,and one in now being finished but his is at painters over winter so be a while before thats dynoed be easier and cheaper for martin to pop his on mine he is local too ill not charge for a run and i speak to him so all good to go ,im sure it will be unchanged from york and reading very similar between ian embertons dynojet/the projex dynapro and perhaps mine reading a hp higher at most ,what settings did they run the dynapro on ,,djchp ? corr factor ? ive got a friend who uses projex and posts his graphs online , differ alot some are djchp some not some one corr fac others different not sure why ,thats why i post a full pic of my graphs so the info can be seen