Cam Timing Questions.

[Linga]

I have been helping a friend with their 85 supra 5MGE and we wanted to check the timing belt and timing of the cams. We took off the top timing cover and set the timing to TDC. I made sure it was on the compression stroke. I noticed on the cams there is a T and an E on opposite sides of the each cam gear. Both have a dot. The person who owned the car before put a white mark on both dots. Set at TCD one cam is lined up with the T and the other with the E. Is this okay? I went to my 84 and put it at TDC and took the upper timing plate off and mine were lined up both on the E. I did a search on the forum and found pictures of someone who had them both lined up on the T. So, whats the right way to do this? And what do the T and E stand for?

[pat2330b]

Put both T on top ( T mean TOP admission time and E is exhaust time ) in a 4 strock engines, Cylinder 1 is on the uper edge TDC on beginning of admission Time(T) and is on the upper edge on exhaust time (end)EDC. Cylinder one and six are stroking the same way (same for 2-5 and 3-4). If you put E on top for both cams you will have to put the distributor on firing in the cylinder 6 instead of 1. It is impossible that the engine runs with a T and E on top or something has been modified.

[Linga]

His car cuts out at around 2500 RPM if the TPS is plugged in. That is the only problem. He drives with it unplugged until we figure that out. We were just looking around and found this and I thought it was weird. Mine is set on the E and runs great. The dissy is set on the number one plug like it should be. Should i take the cam gears off and make sure the pin for alignment is still there? Any thoughts on the cut out at 2500 RPM?

[pat2330b]

The pins are there for sure otherwise the timing would have move from its original position. If both are on E an it run fine the distributor is set ok on cylinder 6 (or cylinder 360/720 degrees of no 1 )

[Linga]

What kind of mod would make it to where the car would run with the cam gears set like that? I don't understand. It has stock cams and runs good besides the cut out. Should I try and set it up on the T like it should be?

[84ptype]

Take the oil cap off and line up the cam journal (whole in the cam you can see with a flashlight) and take the exhaust side valve cover off to line up that one.
Distributor on number 1 cylinder
crank at TDC.
put back together, turn over twice by hand to make sure everything is still lined up.

If good start the car and check ign. timing with light.

Jump check connector and adjust as needed to get 10*

http://www.cygnusx1.net/Supra/Library/TSRM/MK2/manual.aspx?Section=EM&P=15

Start at step 8 and keep going.

[Linga]

Thanks 84 I have done the project before but was wondering how it could be this way and still run. The only thing i can think is someone would have to drill a hole for the pin on the other side of the gear. I don't think anyone would do that though. I will just start from scratch to figure it out. Thanks for the help guys. I now need to go see whats up with my supra. I am pretty sure its not 180 out. But who knows.

[Donn29]

Woah woah stop.

The TPS issue you have is causing it to stall at ~2500rpm? That probably means the TPS is telling the ecu you don't have your foot on the gas, and its kills the motor until it gets close to idle.
See here:
http://www.cygnusx1.net/Supra/Library/TSRM/MK2/manual.aspx?Section=FI&P=79

Here is come pictures showing how its done too: http://forums.celicasupra.com/showthread.php?t=47753&highlight=cam

[Linga]

Thanks Don!
I noticed in your pictures you have the cams set on the E dot not the T dot. Is there a reason for this. This was the original reason why this thread was started. Mine are set on the E dot, My friends are set with the T dot on the left cam and the E dot on the right cam. According to Pat it should not run this way and should be set on the T dot. If set on the E dot it is 180 degrees out. My friend has tried 3 different TPS's and had nothing change. I might take mine off since I know its good and put it on his to see if it makes a difference. Thank again guys!

[Donn29]

TPS issue, it could be a wire shorting to something else. You'll need a volt meter to properly figure that one out.

For cam timing, IIRC, the letters don't matter, follow the TSRM in Scott and I's post. Turn the crank to 0 then see if yours lines up like the tsrm.

[pat2330b]

Thanks Don!
I noticed in your pictures you have the cams set on the E dot not the T dot. Is there a reason for this. This was the original reason why this thread was started. Mine are set on the E dot, My friends are set with the T dot on the left cam and the E dot on the right cam. According to Pat it should not run this way and should be set on the T dot. If set on the E dot it is 180 degrees out. My friend has tried 3 different TPS's and had nothing change. I might take mine off since I know its good and put it on his to see if it makes a difference. Thank again guys!

i sand,you can run the engine on T dot on top firing in cyl 1 or E dot on top firing at 6 because these(1-6) cyl stroke at the same time (360 degrees difference) 4 time engine is 720 degrees. 1 time = 180 degrees on the crank. so 720 degrees is 4 time(admission, compression, engine stroke, exhaust) =2 RPM.

You gotta strange problem(T and E on top) , if i were you, i would remove both valves covers and check cams lobes position on cyl one before checking TPS problem. You have to make sure the timing is set right.

[Linga]

i sand,you can run the engine on T dot on top firing in cyl 1 or E dot on top firing at 6 because these(1-6) cyl stroke at the same time (360 degrees difference) 4 time engine is 720 degrees. 1 time = 180 degrees on the crank. so 720 degrees is 4 time(admission, compression, engine stroke, exhaust) =2 RPM.

You gotta strange problem(T and E on top) , if i were you, i would remove both valves covers and check cams lobes position on cyl one before checking TPS problem. You have to make sure the timing is set right.

I wasn't trying to say you were wrong. I really appreciate your help. I understand that there is two revolutions of the crank shaft to get all four stokes. I have always known TDC to be the number one cylinder, compression stoke all the way at top stroke. ( 0 on the crank shaft timing plate). So your saying if I cranked the engine all the way around to TDC in number one again (720 degrees of the crank shaft) it would be lined up on the T dot? Or are you saying I have my cams flipped around 180 degrees if I am at TDC on number one, and I am lined up on the E dot.I still might be confused. If I am set up on the E dot or the T dot I can still be TDC in number one cylinder? Sorry if I am just not getting it.:duh: But, I am really trying to understand.

[pat2330b]

no problem, i just want to be sure you understand. If you put the crank at 0 degrees on cylinder one you have to choises (TDC or EDC) mean 2 marks at T on top or two marks at E on top. If its on T marks the distributor should be firing on cyl one, if its on E marks it fires on 6(cause 1 and 6 are on the same strokes,just 360 degrees intervall) Cause 4 strokes mean 2 engines turn=720degrees. In these two turns, while cyl 1 is on firing (TDC) cyl 6 is on exhaust time(EDC). Cyl 2-5 and 3-4 work the same way.

[Donn29]

I wasn't trying to say you were wrong. I really appreciate your help. I understand that there is two revolutions of the crank shaft to get all four stokes. I have always known TDC to be the number one cylinder, compression stoke all the way at top stroke. ( 0 on the crank shaft timing plate). So your saying if I cranked the engine all the way around to TDC in number one again (720 degrees of the crank shaft) it would be lined up on the T dot? Or are you saying I have my cams flipped around 180 degrees if I am at TDC on number one, and I am lined up on the E dot.I still might be confused. If I am set up on the E dot or the T dot I can still be TDC in number one cylinder? Sorry if I am just not getting it.:duh: But, I am really trying to understand.

Just follow the TSRM, and you can't go wrong, if you are still having timing confusion.

[Linga]

Thanks again guys. Your wisdom is greatly appreciated!