timing suggestion

[twilightprotege]

can someone, preferably with experience, let me know what timing i should set my engine to?

 

it's an MPFI (so 9.7:1 comp ratio) with the stock turbo. also have a legacy waic.

 

it's a 3 plug ecu, so vacuum advance. i know the stock engine requires 20 degrees BTDC with the vacuum line plugged, and i assume that's on 89 fuel. i'm running 91 fuel.

 

thoughts? suggestions?

[MilesFox]

25 deg if you have a mechanical disty. 20 deg if its optical

[twilightprotege]

yeah that's not right.

 

it's a mechanical dizzy (ie vacuum advance)

 

and advancing the timing is not what's required when you increase the compression ratio. stock 3 plug turbo is 20 degrees BTDC. with more compression, the timing needs to be more retarded (like 10 degrees BTDC)

[MilesFox]

maybe specs are different out your way. In USA, the timing is 25 deg for 85 and 86 mpfi turbo with external knock control unit.

 

spfi runs at 20 deg. with the mechanical disty you set the initial advance and the knock control unit retards the timing. but the engine can never go higher than the initial timing, hence 25 deg for up to 25 deg.

 

I have built a turbo onto a carb block, 9.0 compression ratio with stock ecu and boost, stock timing on 87 octane fuel.

 

if you are running stock boost, you should be alright within stock parameters.