Boost Question

[SShafranko]

When i had my Edge i used to boost to 42psi. Now with the Smarty the most i see is 35psi. It was probably all hot air anyway after 35 but iam curious as to why the change. I also have a boost fooler hooked up. My EGT's are pretty much the same as before 1250. Thanks in advance.

 

[CToney]

I assume that you had an edge att. They seem to show a higher boost # than with a mechanical gauge. You shouldn't need a boost fooler with the smarty. It will boost fool to 44psi. Your truck will run better without the fooler. You can turn off the wastegate I believe with the smarty. With my smarty JR I can see over 35psi without a fooler. Where are you running the smarty?

 

[JJPage]

My guess is the Smarty's timing is more advanced than the Edge, back the timing off on the Smarty. Your turbo will spool quicker, and your boost will increase, however your mileage and power may be less.

 

[cerberusiam]

Smarty does not boost fool, only modifies the boost tables to stop codes. You need the fooler if the WG off does not work which it doesn't some times.



What boost fooler do you have?



What tune on the Smarty are you running?



FYI, on SW #4 Timing 4 my truck easily exceed 40 psi with the WG blocked, I have seen over 45 psi with the higher power tunes.



With the boost fooler 40 was the top it would ever hit even with max fuel under a load. Might try blocking the WG and see if it makes a difference in the max numbers.

 

[CToney]

Correct me if I am wrong. The Map sensor can read boost until it reaches 44psi. A smarty continues to read the correct pressure and fuels accordingly. A boost fooler only works when max stock boost is reached by telling the ecm that boost is below max from which it will send more fuel and (on '04. 5 and up keep the wastegate closed). If a programmer is installed more fuel will be sent and boost levels may be increased.



I guess I have been caught using terms which are not correct. There is usually someone who has more experience than myself. But if you don't make a mistake or two you don't learn very much.



Some people have stated that you don't need a wastegate until you reach 400-450hp. Is there any truth in that? Your wastegate really should only ever be open under full power which unless you tow should't be very often.

 

[cerberusiam]

Correct me if I am wrong. The Map sensor can read boost until it reaches 44psi. A smarty continues to read the correct pressure and fuels accordingly. A boost fooler only works when max stock boost is reached by telling the ecm that boost is below max from which it will send more fuel and (on '04. 5 and up keep the wastegate closed). If a programmer is installed more fuel will be sent and boost levels may be increased.



Some people have stated that you don't need a wastegate until you reach 400-450hp. Is there any truth in that? Your wastegate really should only ever be open under full power which unless you tow should't be very often.

Correct, the MAP will only read to around 45 psi. Whne you load the Smarty it simply rewrites the boost tables to the max limit so the ECU program does not run out of entries and defuel. Smarty can't read any higher than the map but it really doesn't care as it just wrties entries to a fueling table that controls the duration of the event.



All that still does not stop the overboost code because that is hard coded into the program, it just fixes the tables so it will fuel higher. A true boost fooler clamps the voltage output from the MAP ta value that won't cause a code but allow the ECU program to just apply the table values.



The WG is seperately controlled by the ECU and its relationship is set by another hard coded value that will limit boost to around 30 psi. Clamp the MAP voltage to around 28 psi and the error routines never kick in.



The WG should really be used to limit drive pressure and keep a balance between it and boost but it used to limit boost for emissions reasons. The higher the boost goes the more fuel is added and higher the cylinder pressures go which creates more NOX. Limit the boost by pulsing the WG and you eliminate an emissions point.



To the OP's point, it varies what is seen for boost because the electrics reading the MAP are not quite as accurate as an analog. This number needs to get adjusted by the Edge as the MAP is reading absolute pressure not just boost, the adjusment routines seem to throw some differentiation to analog into the readings. The way the Edge was making power is not the same as the Smarty so comparisons don't always work.



The 35 psi on an analog gauge with a lower Smarty setting and BF is about right. The stock turbo does pretty good to 40 psi, at least the EGT's will reflect that. Beyond 40 psi is when drive pressure and hot air start impacting the ability to make more power and keep it cool.

 

[LRutigliano]

My guess is the Smarty's timing is more advanced than the Edge, back the timing off on the Smarty. Your turbo will spool quicker, and your boost will increase, however your mileage and power may be less.

X2 !! When I changed my timing from 2 (default) to 3 (aftermarket injectors), my boost went up approx 4psi. Also, the different SW levels will affect boost too. Its not linear, its very dynamic so you have to experiment a little to find the right SW and parameter settings that work for you.

 

[SShafranko]

Thank you very much for all your replies. My boost fooler is a Quadzilla. It sounds like i should remove it correct? I havent tried running with the WG off but i will in a minute. My Smarty is set to SW9 TQ2 RP1 Timing2 and i fluctuate on the POD settings from 70 to 99 depending on the situation and mood. I did go to a mechanical boost gauge from the edge but did not think that there would be a 6psi error difference between the two, so i figured that something was not right. The reason why i installed the fooler was to see if i could get it back to 42psi again but i guess i was going about it the wrong way.

 

[JJPage]

Thank you very much for all your replies. My boost fooler is a Quadzilla. It sounds like i should remove it correct? I havent tried running with the WG off but i will in a minute. My Smarty is set to SW9 TQ2 RP1 Timing2 and i fluctuate on the POD settings from 70 to 99 depending on the situation and mood. I did go to a mechanical boost gauge from the edge but did not think that there would be a 6psi error difference between the two, so i figured that something was not right. The reason why i installed the fooler was to see if i could get it back to 42psi again but i guess i was going about it the wrong way.

Leave the POD@100%



Leave the boost fooler on. If you are running Revo, try SW7, RP2,TQ3, Timing 3 or 1, 1 will be less timing more boost, but 3 you should see more boost than your seeing now, wastegate 1/off.



If you are running TNT, try SW5 OR 7, same settings except timing, you are on 2 now, in this order try 3, 4 ,1 each will give you less timing, 1 being the least timing and should give you the most boost.



By your sig, looks like you may have a stock CP3, you may not be able to support TNT above SW5?? Try this, I believe you will see more boost and be happy.

 

[SShafranko]

Thanks JJ. I am currently running the REVO not the TNT. I modded the CP3 myself. I haven't drained the rail on any of the revo programs so far.



Are you saying that i will get more boost on 7 as oppose to SW9? Why? And will it equal more power than SW9? Thanks

 

[JJPage]

Thanks JJ. I am currently running the REVO not the TNT. I modded the CP3 myself. I haven't drained the rail on any of the revo programs so far.



Are you saying that i will get more boost on 7 as oppose to SW9? Why? And will it equal more power than SW9? Thanks

Depending on the condition of your CP3(high mileage,etc) some folks believe SW7 is stronger... I would have to see it on a dyno before I would believe it.

Personally, I did not feel any difference between 7 and 9, but 9 smoked more so I know it fuels harder.



Keep it on SW9, as long as your maintaining rail pressure, cool.

 

[SShafranko]

Turned off the WG and I'm up to 39 psi. Gonna try timing on 1 and see but I prefer to stay on the better mpg setting of 3. Thanks for help. I guess ill leave the fooler on?

 

[JJPage]

Let us know how it works out.