Locked Dizzy for turbo, how necessary?
 

alright, im finishing the rebuild, and the distributor is pretty much the last thing before i put it back together. i tried to get one of the screws out and the metal around the slot started to get out of shape.. at this point, im tired, broke, and just want to try the thing out (got cartech turbo setup) so how important is it to lock the dizzy? i mean the kit was made to be a bolt on, right, so is it that cruicial?

(edit: and let the 83 LE wheel thread die so no one outbids me, hehe)

It's definately necessary for higher boost. I would say anything over 5-6lbs would require retarding or locking the dizzy.

I have been told you can just take the springs out, and it worked just fine.

well im looking at 5-8psi i think. my problem was the screws were breaking away as i was trying to get to the springs, so i just left it so i wouldnt have to try drilling the screws out and replacing them or getting a new distributor all together

Have you tried breaking them loose with an impact screw driver, before the heads are totally fubar?

ill try that next.. they were pretty bad to begin with (looks like sumone else gave up on it before i even got to it)

There's an 83LE wheel thread?

Goddamn those are the rims I want!

But I s'pose you can have 'em. I just went broke on all the stuff I put in my engine bay.. I'll grab the next set.

Jon

I raised this issue last September. The best response was from FBII ", just back the total timing out a little. as long as you dont go over 10 degrees TOTAL advance you will be rockin out! mine is always locked... 10 degrees advanced at 16psi. works beautifully"

This is what I did on my 12AT, and the concept has worked perfectly for 10-12psi

Hey, a fellow Cartech turbo guy!! Which bolt on setup do you have. Is it the drawthru 5-8 psi INI turbo with Holley carb? If so I may need to pick your brain because the 380 cfm Holley I have has some tuning issues that I put on hold for the winter. Btw I also wonder how good a solution a locked dizzy is. Granted locking it will prevent the auto advance from advancing timing to a dangerous level during high boost but doesn't it also sacrifice low end response with the time so advanced? The Cartech manual doesn't mention any alteration to the dizzy so I think with the low boost it should be fine.

locking the distributor definatly wont hurt , especially with the shit gas we have now compared to when the cartech kit came out.. back in the day we had higher octane with leaded fuel , you can get away with a stock distributor,,,, not any more :(

Retarding the timing is pretty much the same idea as running water injection.

Its a method used to help prevent engine damage due to pre-ignition detonation.....but the actual usage of the method will reduce the engine's output.Engines like ignition advance,its just something that is, and cant be undone.

Yes,it can save your engine by preventing detonation,but if the engine detonates in the first place,then theres something wrong with it that you need to fix,be it the fuel quality,mixture,temperature,intercooling,ect,ect.
With the rotaries somewhat fragile nature in regards to detonation,cranking the ignition back a bit is not a bad idea.
I did some reading in the S5 FSM on the TII igniton and timing system a while back.I wish it listed the actual advance curve and timing values,but in a nutshell,the stock TII engine runs standard type ignition advance at all times,just like any other engine.According to the input/output device flow charts,the only time the ECU pulls the advance back is when the knock sensor intervenes with a knock signal.Then it can retard up to 5* of ignition advance until knocking is controlled.Most people agree that the stock knock sensor system is junk and running the best gas you can get is a small price to pay for engine protection.A good knock control system like the J&S can save your engine when tuning to the boundaries or turboing an N/A engine,but they can be pricey.

FWIW,Ive run the stock igntion timing and basically the entire stock ignition system on my S5 for years and years with not a single problem.And thats with higher compression S5 TII rotors and 14psi of boost.I attribute my success to consistant tuning and setup(Im not pushing for more power or performance),attention to tuneup needs,adequate intercooling/engine cooling,and plenty of fuel going into the engine.Maybe a little too much actually,but very few turbo rotaries will complain about a rich mixture.....

yeah, draw thru holley setup, got a 600cfm though. i just locked it, after readin the last couple, i suppose i woulda been better off without, but if theres any slight chance of detonating the engine i just rebuilt and havent put in yet, then id rather be safe about it. we'll see how it goes and then maybe i can help you out, or maybe we'll both be in trouble, who know