Locking Standard Dizzys For Boost

[SLW42]

Hi guys I am just wondering how you lock a standard dizzy so it doesn't advance with boost,

 

Do you just remove the line for the vac advance or do you physically have to lock the dizzy internally, all help is appreciated

 

This stuff is above my knowledge and havnt really mucked around with turbo cars with a dizzy :P

[philbey]

You need to remove the points plate and it he guts of the dizzy I's a little advance weight mechanism, two weights that move through centripetal force withsprings attached. Most peopl exist wire the weights together, if you were to get fancy you'd make a plate that locks it out.

 

There's actually a bunch of articles on locking and recurring on the net, Rodgers journal and so on, better explanation than I can give without pics.

Edited March 19, 2012 by philbey

[snot35]

What are you trying to achieve? A dizzy has two advance mechanisms, one the mechanical advance philbey mentions, the other vacuum advance which won't work properly if you are running boost. You can just disconnect the vac line from the canister to disable vacuum advance. Do you want to remove all advance?

[ke70dave]

i don't really agree with locking distrubuters, but people seem to have success. i suspect the driveability of the car is considerably reduced. especailly trying to start a car in winter with excessive spark advance form the get go.

 

i suppose there is no easy fix on a bitsa carby turbo though, other than locking the dizzy and hoping for the best.

 

the model T had a lever on the steering wheel where the driver could adjust the spark advance himself (mainly so he could retard it completely, so his arm wasnt ripped off when hand cranking the engine), this is better technology on a street car than locking it completely! and that is from over 100yrs ago!!

 

i would throw the dizzy in the bin and setup something electronic to control the spark, but that would get alot more complicated.

 

although this is corvette material, the content applies to all engines with vac and mechanical advance distrubuters

 

http://www.corvette-restoration.com/resources/technical_papers/Timing101.pdf

 

very interesting reading.

Edited March 19, 2012 by ke70dave

[snot35]

I concur :)

[altezzaclub]

Nice find Dave!

 

As it says, you need more advance at higher revs to get the burn at the right time, so having a locked dizzy is giving away performance somewhere.

[kickn5k]

Well I never had any major issues. Sure it wasn't the easiest car to start when cold and they require a little more fuel at idle. Was plenty enough spark for a smidge over 100rwkw @ a measly 8psi. In a car the weight of a KE-11 would smash STD/mild WRX's and keep up with early M3's. So in all not as bad as most people believe!!!!!

 

Just use stainless mig wire, all I used. I try and dig up my old points dizzy, and take dome photos to explain it.

Stu.

[snot35]

Did you do a before and after? i.e. pre and post locking?

[kickn5k]

Did you do a before and after? i.e. pre and post locking?

 

I did, but with it wound down to about 3btdc it would ping it's brain off up top(so was still 35deg total advance) and was also doughy as all ʞ©$ɟ down low. Then locked it, wound to full advance(about 28btdc with some dremel work). Made the most power at around 28btdc.

As much as it worked ok, it could have been better. But for what it costs compared with full efi its not so bad. when I get to my laptop I'll link the start vid of it I have on YouTube.

 

Hey slw42. You should buy yld10s supercharger/efi kit he's selling(my old setup). Good for almost 120rwkw with the right cam.

 

Stu.

Edited March 20, 2012 by kickn5k

[SLW42]

Cheers for the info lads!! Appreciate it, Dave ill have a look at that thread in a minute

 

Nah stu I have a T04e with a .64 rear housing(shouldn't be tooooo laggy, but we will see), will be getting a webber, 38mm external gate, going to get a cam re ground for low-mid range revs, then let the turbo do the rest, 12:1 rrfpr and, wont be running a intercooler setup at all, yet to decide what car it will go in but will be on a 4k!!!! Butt SHHHHHHHHH

[philbey]

If you want to get a little more serious, buy the MSD 6AL programmable. Lock the dizzy, run a boost reference and properly tune your ignition curve.

[ke70dave]

i reckon a 38mm external gate is a sliiiigghtt over kill on a 4k turbo!

 

i always wanted to try one of the old falcon throttle body injection systems on a 4k.

 

i reckon thats got to be the easiest way to get some injectors/EFI onto a 4k.

[SLW42]

Cbf with efi and all the b/s that comes with it I.e fuel lines, manifold, tb, then computer to run it

 

I know it will need dyno time to perfect it, but 4k's are cheap :P hahaha and it only takes Afew hours to lift one out and in

 

I'd use a smaller gate but I have the 38mm already plus the turbo has no actuator/internal wastegate on it so i will run the external gate anyways, plus external gate sounds better :P haha