Change from Dizzy trigger to crank trigger?

[Guest |359|]

I'm setting the V88 up soon, and was thinking about the ecu triggers.

The 1FZ from the 80 series uses a distributor, and as the ignition is now a multicoil, I was planning on making a cap for the dizzy and just using it for the triggers.

I was thinking however, would be a good idea to change to crank pickup - with the dizzy just for cam signal?

My concern is that the dizzy is driven by a chain and then a scissor gear, and so there is conceivably some float in the trigger in relation to the crank/slugs.

So the question is : Is it worth changing to crank trigger - or is the slight float in the trigger so small as to not be worth the trouble?

The set up will be mechanically capable of over 1200hp - so I want to be sure I have the best possible inputs for the ECU.

Whaddya reckon?

Sean

Adelaide

[rayhall]

Sean,

The standard 1FZ engine is a low rpm engine and there would be no problems with the distributor based triggers. On very high rpm race engines a crank trigger is required for accurate ignition. If the engine is going to operate well above 6000 rpm then use a crank trigger.

[Guest |359|]

Cheers Ray.

The motor is intended to run to over 8000 rpm, so I'll change over.

When I make up a triger disk, is there any specific material I should use, and how many teeth should it have?

One other question - should I change the cam trigger to be directly off the cam, rather than the dizzy also?

Thanks

Sean

[rayhall]

Sean,

The crank trigger disk must be made from mild steel (low carbon steel). The thickness 5mm to 6mm. The teeth must be raised, you cannot use slots in a disk. Use 24 teeth. The tooth size should be 6mm long and 6mm high. The outside diameter of the disk (teeth) must be machined and run true.

The cam signal from the distributor will be okay as it position is not as critical as the crank signal.

[Guest |359|]

Easy - All clear.

And for my last question on this- I promise.

I have heard of people putting the crank trigger disk at the back of the motor.

On the 1FZ doing this would be particularly easy.

Given I have to start from scratch with the trigger set-up regardless of if if is on the balancer or in front the flex plate, is there any benefit to be had by putting the trigger disc it at the rear of the motor?

Thanks Ray.

Sean

[rayhall]

Sean,

Front or rear of the engine does not matter, and I cannot see any advantage.

[Guest |208|]

I imagine the only advantage on mounting at the rear of the engine would be in cases of limted space to mount it in the front.