Pulley size change and retune always needed?

MineralCobra

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Hey guys,

Just curious if someone can explain a little about my question below.

Lets say 03 cobra tuned big blower e85 making good power on 3" upper 4lb lower everything dialed in running like champ.. now if you swap to 3.5" upper running less boost, shouldnt the maf caculate and retune would not be needed.

It just throws me of becuase Im thinking of a turbo car that is tuned lets say to 30psi, then its lowered to 15psi but its still same tune. Curious if the cobras tune functions the same way? I know increasing boost needs new tune but going down in boost?



Thanks
 

Curt@injected

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Yes you should be able to go down on boost without changing the tune. That is if your tuner set you spark tables up correctly. Always best to check it out though.
 

MineralCobra

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Yes you should be able to go down on boost without changing the tune. That is if your tuner set you spark tables up correctly. Always best to check it out though.

Curt Thanks for reply,

Whats the best way to check if the spark tables are set up correctly or what to look for.
 

cj428mach

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Yes you should be able to go down on boost without changing the tune. That is if your tuner set you spark tables up correctly. Always best to check it out though.

This is correct.

Its pretty hard to log timing and know exactly what your timing is actually set at as you have no idea what multipliers if any are being applied.

If you're at a load of 2.0 at wot and you drop boost and are still at a load of 2.0 then you're still on the same timing cells.
 

Curt@injected

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Correct. That would be the only instance where you should have an issue. These processors will only go up to a load of 2.0

That said, in this scenario the worst that would happen is you would be a little low on spark.
 

MineralCobra

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Correct. That would be the only instance where you should have an issue. These processors will only go up to a load of 2.0

That said, in this scenario the worst that would happen is you would be a little low on spark.

I agree, I was just letting him know that if he drops boost but load stays at 2.0, then he'll know that he should be ok.

Thanks guys appriciate the response, I do have a way to log it but have some other issues to resolve 1st.

During initial tune session I had a boost leak thru intercooler orings at higher boost, since the repair now its going a little lean in upper rpm w all the boost so have to fix that before any wot testing.

But this is great info to know.
 

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