Hey everyone, ive had my long journey with bulding my 91 camaro. Its been a few years since ive worked on it but lately i have found some energy to get the project back on the streets. I have a 350 sbc rebult with stock parts. Ive added a single turbo to this car and bought the msd 6al-2 programmable box for tunning. Now as i recall when setting this box up you have 2 maps. Top map is your normal timing with NO boost and bottom map is the psi and timing to be pulled WITH boost. Well since the bottom map is not in psi but rather in psia, you needed to plug the msd box to your conputer and it should read the pressure level and you would start your configuration from that pressure level. When i plug the msd to my computer it reads me a pressure level of 7.75. That doesnt seem right, im almost sure it should be in the 14's. Am i not doing something correct? I have provided a picture of my computer screen when plugged into the mad box

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your MAP sensor setting might not be right .

Make sure its set for the sensor your using .

Also I think the run retard and boost retards are added together .

Theres no need to run the run retard other than using it as a start retard . Pull timing below 500rpm .

Boost retard will also show vacuum so you can use that in cruise also , but remember about rotor phasing . You dont want a big swing in timing .

I would lock it at what it like NA and run that timing eveywhere out of boost , and only use the retard in boost .

 

Very well put. Keep in mind as stated to drop timing under 500rpm to help cranking (Starter). The maps do work together. Fro off boost tune for clean cruise. For boost be a little conservative on timing and AF and work your way up.

I have the same box - great unit and functionality for the price

 

I figured out the graph, you were right about having to reset for a 2 bar map sensor. So next question is what would you guys set the base timing to? And what should i pull upon start up? As for pulling timing for boost, the car will see between 7-8psi. How much timing should i pull per psi? And what psi level should i start pulling at?

 

What kind of fuel you running?

 

Pump 93

 

Lock dizzy at 36*, start pulling 1* per pound at say 2 psi. which will be around 16.00 on your boost retard curve. After dialing in AFR you can get a little more aggressive.

 

Starting with cast stock rebuild and pump gas I'd be conservative and run timing @8psi in the range of 25ish total under boost and work up from there. 1 pop and you could lose a piston.