correct value for warm CHT reading (ohms) Options

[brant]

so my CHT reading was 76 ohms - hot (at 180F oil temp)
I'm reading 2 different things.. on the Brad anders site


one saying that a warm reading should be below 100 ohms
but then the table shows this: for 210F

Sensor Temp = 39 deg. F Temp = 61 deg. F Temp = 210 deg F

0 280 130 003 6.10 K ohms 2.94 K ohms 199.3 ohms
0 280 130 012 NA 2.85 K ohms 191.2 ohms
0 280 130 017 3.63 K ohms 1.74 K ohms 124.7 ohms



I'd love some input from Djet folks about what numbers you see on a warm motor?

brant

[914_teener]

Stock dizzy?

[brant]

Stock dizzy?

this motor was Jason's from AZ
he had it built... and when I bought it from him it was a full Djet motor
he told me the shop had put a "mild" FI cam into it, but don't know which one
I don’t think it would be a raby cam. Probably a webcam

the cam absolutely runs out of lift at 5900
I never typically shift above 5600 as there is no reason
but I rode it out... for the purpose of seeing what the AFR did.

its stock dizzy... all stock injection... the only modification is to the ignition with a Hall Effect, pick up... and a crane/highwire (?) CDI type box.

I'm betting the slightly lean highway condition is the reason I get 32MPG @85

but that I can improve on it some...
I also now believe that my plugs are fine... and yes I might be seeing a tiny bit of a lean condition on the highway.. but doubt the plugs can even show much difference

brant

[914_teener]

Stock dizzy?

this motor was Jason's from AZ
he had it built... and when I bought it from him it was a full Djet motor
he told me the shop had put a "mild" FI cam into it, but don't know which one
I don’t think it would be a raby cam. Probably a webcam

the cam absolutely runs out of lift at 5900
I never typically shift above 5600 as there is no reason
but I rode it out... for the purpose of seeing what the AFR did.

its stock dizzy... all stock injection... the only modification is to the ignition with a Hall Effect, pick up... and a crane/highwire (?) CDI type box.

I'm betting the slightly lean highway condition is the reason I get 32MPG @85

but that I can improve on it some...
I also now believe that my plugs are fine... and yes I might be seeing a tiny bit of a lean condition on the highway.. but doubt the plugs can even show much difference

brant

My thought was this Brant:

The stock dizzy, and I'm assuming yours still uses the trigger points to fire the injectors,makes a huge difference with regards to wear and alignment of those things as far as injection pulse goes. That'd be my experience.

I too , am surprised that yours still makes any power at or even near 5900K


With regards to compression...according to Raby he never recommended to go over 8.5:1 when running D-jet, so I don't know what yours is. That what I remember hearing. Not to mention heads.....they are the heart of a T4 and its weakest link.


In any case, I eventually ditched the stock dizzy for reliablilty sake. No more points and no more trigger points.

Car ran like a top after I got the mixture right. I saw variations up to 9k feet when driving in the local mountains but not at sustained speeds up there on the top of the Mogollon plateau like you do.l

I don't know what you can do other than that and or a potentiometer on the CHT lead.

Those be my .02.

[brant]

Stock dizzy?

this motor was Jason's from AZ
he had it built... and when I bought it from him it was a full Djet motor
he told me the shop had put a "mild" FI cam into it, but don't know which one
I don’t think it would be a raby cam. Probably a webcam

the cam absolutely runs out of lift at 5900
I never typically shift above 5600 as there is no reason
but I rode it out... for the purpose of seeing what the AFR did.

its stock dizzy... all stock injection... the only modification is to the ignition with a Hall Effect, pick up... and a crane/highwire (?) CDI type box.

I'm betting the slightly lean highway condition is the reason I get 32MPG @85

but that I can improve on it some...
I also now believe that my plugs are fine... and yes I might be seeing a tiny bit of a lean condition on the highway.. but doubt the plugs can even show much difference

brant

My thought was this Brant:

The stock dizzy, and I'm assuming yours still uses the trigger points to fire the injectors,makes a huge difference with regards to wear and alignment of those things as far as injection pulse goes. That'd be my experience.

I too , am surprised that yours still makes any power at or even near 5900K


With regards to compression...according to Raby he never recommended to go over 8.5:1 when running D-jet, so I don't know what yours is. That what I remember hearing. Not to mention heads.....they are the heart of a T4 and its weakest link.


In any case, I eventually ditched the stock dizzy for reliablilty sake. No more points and no more trigger points.

Car ran like a top after I got the mixture right. I saw variations up to 9k feet when driving in the local mountains but not at sustained speeds up there on the top of the Mogollon plateau like you do.l

I don't know what you can do other than that and or a potentiometer on the CHT lead.

Those be my .02.

great 2 cents!
and I know I've never adjusted the trigger points.
they have to be 50 years old by now
so a very good idea of something to check

did you go with the blue tooth/fancy new distributor that everyone is using?

brant

[914_teener]

Stock dizzy?

this motor was Jason's from AZ
he had it built... and when I bought it from him it was a full Djet motor
he told me the shop had put a "mild" FI cam into it, but don't know which one
I don’t think it would be a raby cam. Probably a webcam

the cam absolutely runs out of lift at 5900
I never typically shift above 5600 as there is no reason
but I rode it out... for the purpose of seeing what the AFR did.

its stock dizzy... all stock injection... the only modification is to the ignition with a Hall Effect, pick up... and a crane/highwire (?) CDI type box.

I'm betting the slightly lean highway condition is the reason I get 32MPG @85

but that I can improve on it some...
I also now believe that my plugs are fine... and yes I might be seeing a tiny bit of a lean condition on the highway.. but doubt the plugs can even show much difference

brant

My thought was this Brant:

The stock dizzy, and I'm assuming yours still uses the trigger points to fire the injectors,makes a huge difference with regards to wear and alignment of those things as far as injection pulse goes. That'd be my experience.

I too , am surprised that yours still makes any power at or even near 5900K


With regards to compression...according to Raby he never recommended to go over 8.5:1 when running D-jet, so I don't know what yours is. That what I remember hearing. Not to mention heads.....they are the heart of a T4 and its weakest link.


In any case, I eventually ditched the stock dizzy for reliablilty sake. No more points and no more trigger points.

Car ran like a top after I got the mixture right. I saw variations up to 9k feet when driving in the local mountains but not at sustained speeds up there on the top of the Mogollon plateau like you do.l

I don't know what you can do other than that and or a potentiometer on the CHT lead.

Those be my .02.

great 2 cents!
and I know I've never adjusted the trigger points.
they have to be 50 years old by now
so a very good idea of something to check

did you go with the blue tooth/fancy new distributor that everyone is using?

brant

Yea...I did. Pricipally because I couldn't find a non-leaking advance canister and didn't want to waste $110 bucks on a new set of trigger points.

I was having similar symtoms as you are now. I never did install the new thermister for the CHT that McMark used to make. I think 914 Rubber sells them now though.

Missed you on the ole R66. No 914 on that trip for me. I'm getting old so I took a water pumper instead.... (IMG:style_emoticons/default/slits.gif)