What will go wrong, part 568240 - Dyno time..

[Glenno]

Usually when someone says the Dizzy is fucked its because a rod came out & smashed it.

That would just be an electrical issue

[edo]

That would just be an electrical issue

Nah, thats when the rod hits the altenator.

[F|sh]

over heating issue?

rod came out and took out the radiator hose?

[Rhys]

Has it caught fire before/yet?
A fire will be nice

[HoonBoy]

Damn this car is a pain!

Dissy was screwed, when the timing was right, the rotor button wasn't in the right place so it had to be modified so that the rotor phasing was correct. Also had about 15 degrees too much advance at maximum, so that had to be fixed. It was still running crap, so it was put on the dyno to check air-fuel ratio, it was running real bad, lots of misfiring and black smoke. Tried a few things and managed to get a whole 38hp out of it... decided that the cam timing must be out, so it was pulled of the dyno and cam timing checked. Inlet cam was out by one tooth, fixed it, waited for the head to cool down and retensioned the head.

Back on the dyno and it was running better, but not good. Air fuel showed lean, everything else pointed to it being rich. Tried a heap of stuff with the carbs and got it slightly better, tired everything to get the air speed up in case it wasn't atomising the fuel properly. Changed spark plugs as the current ones were looking fairly black and finally got some decent sounds out of it. Highest power for the day was 98hp@5000rpm with mega rich 10:1 afr's, got the mixtures down to 14:1, need to get it somewhere in the middle . At least we have it so the mixture reading is the same as what is happening. Still need to sort out an issue with the linkages that is impacting on the idle speed, balance the carbs, run inthe engine and tune it for power. Once that is done we can start on the nitrous as long as nothing else goes wrong..

[oldcorollas]

if it is misfiring badly, then you will have fuel and "unburnt air" going into exhaust and showing lean on the AFR....

[F|sh]

thats a start dude!!!

I got my engine back today and i have to start building it. Hoping to reach about the same hp with the cam specs i have. Then we can see who is quicker :D

[HoonBoy]

if it is misfiring badly, then you will have fuel and "unburnt air" going into exhaust and showing lean on the AFR....

Yep, well aware of that. There was an obvious missfire there to start with whcih we sorted out, then it sounded smooth but gutless. Had to find out it if was ignition related or fuel not atomising.

thats a start dude!!!

I got my engine back today and i have to start building it. Hoping to reach about the same hp with the cam specs i have. Then we can see who is quicker :D

It will go higher, we stopped at 5,000rpm as the engine is not run in and the mixtures were not right. Factory peak power is at 6,800rpm. Torque curve was nice and flat as well.

I'll try to not stand next to the cooling fan with the camera next time too http://www.youtube.com/watch?v=mXL1mmcEKOs

[Babalouie]

Whaddya mean by rotor-phasing tho?

I would have thought that if the ignition timing's right, then then #1 plug is firing at the right time (and hence) the rotor must be in the right spot? Or is there more to it?

[AlexinPerth]

Sounds like the dizzy cap might have been the wrong one. (ie, cap is rotated slightly from the correct one)

Alex.

[HoonBoy]

Whaddya mean by rotor-phasing tho?

I would have thought that if the ignition timing's right, then then #1 plug is firing at the right time (and hence) the rotor must be in the right spot? Or is there more to it?

Slightly more to it, when the pickup was aligned and ready to fire, the rotor button was not lined up with the dissy cap, hence the pickup had to be moved around so that they both lined up at the same time taking into account movement for mechanical advance. It was causing inconsistent timing and occasional missfire. Think of it as the wrong or twisted dissy cap.

Spending a day with Joe has certainly increased my knowledge of timing, carbs and engines in general.

[AlexinPerth]

Did you check that the cap wasn't just 180 degrees out?

Good luck today, sounds like you're nearly there!!

Alex.

[HoonBoy]

If it was put on 180degrees out then it would be firing 180degress out, cylinder numbers are written on the cap. If I ignored the numbers on the cap then it would be in exactly the same situation.

[takai]

Sounds like they changed the dizzy caps at some point.

I had a paddock basher where the dizzy cap was replaced at some point by one which fit and was very very similar, but about 10deg out.

[HoonBoy]

Possibly, it's also got an aftermarket electronic ignition setup, so nothing can be assumed correct. Just have to work with what we have.