My 99 3500 with Mach 5s ,towing twins and a Mad Ecm seems to be slower than what it should be, before I put on all of the high performance stuff it was abnormally slow for a stock truck, could this be the Map sensor of the injector pump I checked for boost leaks and had none but it has a ton of smoke before the turbos spool so I'm getting plenty of fuel to spool the turbos but they just don't light like they should do yall have any ideas

 

are the turbos modified (balanced, etc)? is the LP starving the IP? any codes?

 

Are you positive that you don't have any boost leaks? Including the unseen type under the headgasket. Also when was the last time you changed out the AIT sensor or the MAP sensor? Lots of smoke with Mach 5s and twins doesn't make a lot sense. I would think the chargers would spool pretty quick. What kind of maximum boost numbers do you see?

 

the ht3b is modified the hx35 is stock,lp is good the IAT is clean and I cleaned the map sensor not sure about the Ip , I have the blow off valves set at 45psi and that is where boost stops, if I'm not really upset abot the top end It is just lacking on the bottom end and with a MAD ECM and twins I figured the bottom end would be better than my dually with ddIIIs and a COMP. I may try a Map sensor but it was clean when I took it out so I not sure

 

I would replace the map sensor and do you have a fuel pressure gauge?

 

will the map sensor lower power without tossing codes? my truck seems to have less zoot then my friends and we are same year/truck/miles/tranny any other symptoms? it runs great just not as great as his

 

ps. it did toss me an over boost code

 

sounds like you need a boost fooler of some type or another/

 

The mad ecm acts as a boost fooler

 

I replaced the map sensor and it didn't really do much any body else have any more ideasI figured the turbos would lite pretty quik with the mach5s and the catcher but if I pin it in the floor in 3rd gear it will only reach about 40-45 psi by 3200rpm

 

Most guys running twins run some type of fueling box, I realize you are seeing smoke at low RPM but maybe what you need is more fuel on the mid to upper end to help spool the large turbo. Another thought goes back to a boost leak, Have you checked the intercooler for leaks? Can you hear your pop-off valves howling once you reach max pressure? Usually you can hear them blowing air past......

Just some ideas,

Doug