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KE70
24th February 2009, 12:58 PM
Finally got my car stated after the conversion but I have a few problems.

I can't get the timing to 10 degrees base (with the bridge in place). I can only get about 2 or 16 degrees, this is buy skipping a tooth on the dizzy.

I am guessing its because my head and block have been decked when it was rebuilt and that has put the cams out a bit, therefore my dizzy is out and I can't get the timing right.

I haven't got adjustable cam gears yet....I don't know where to get them apart from techno T3 and that would cost heaps.

Is there anyway to fix this?

adam
24th February 2009, 02:33 PM
I had a similar problem on my motor a while back (standard motor), the timing was really advanced or retarded. Could never get it on 10 degrees. It turned out to be the intake cam shaft being a tooth out.

I would say double check everything's where it's supposed to be.

KE70
24th February 2009, 02:37 PM
Cams should be fine, they are both lined up to the marks when the engine is on TDC.

Rice86
26th February 2009, 08:09 AM
can u really trust them marks?...

Dish
26th February 2009, 08:18 AM
Just whack it on 16, don't worry about 10. Mine runs at roughly 16-17, no pinging whatsoever, no matter what fuel.

ke70dave
26th February 2009, 04:32 PM
can u really trust them marks?...

er...yes?

what other suggestions do you have....?

mr toyota didnt put them there for no reason, and they arent wrong.

as for the timing, have you bridged the diagnostic port terminals that your supposed to bridge when changing ignition timing?

i just learnt recently (from another thread a few up in the list) that when you bridge the terminals it gets rid of all timing advance from the ecu, and it allows the engine to run with the base timing.

it appears that without these terminals it the timing will be around 15 degrees. but once you bridge the terminals it will drop to around 10 degress and this is the timing you need to set. so i guess for some reason at idle the ecu is putting in about 5 degrees of advancement at idle.

so as others have stated 15/16 degrees is fine. i adjusted my timing yesterday (bigport with a jap ecu) and didnt bridge the terminals, and the most retarded i could get it was the same as you at around 15/16 degrees, and it runs great:D

good luck

KE70
26th February 2009, 06:52 PM
so I left it at 15 degrees and it seems fine when we just free rev it. The problem is that it hesitates when the engine is put on load i.e. driving

Does anyone know what could be causing this?

adam
26th February 2009, 08:26 PM
When you put your foot down, does it take about a second or so for the car to react? It seems 'sluggish'?

My guess would be throttle position sensor.

Edit: Just turn the sensor a little each time and go for a drive. Keep turning until it feels right.

The Toyota user manual has a guide how to do this with a multimeter, but I found that the range the resistance they had listed was way too wide to work with. Trial and error is best in my opinion.

KE70
27th February 2009, 12:51 AM
Yeah it does seem slugish, takes a sec or two to respond.

Thanks for your advise, ill try it after work.

KE70
27th February 2009, 08:46 PM
TPS is stuffed, the resistance moves by itself.