i have an EG with a b20b turbo running ebay turbo, every time when i run when i shift to other gears the car lags for about 2 sec then pulls that happen on all gears from first shifting to second and so on. i check the timing its good change the spark plugs to cold plugs and change the wires too. What i have on my setup is a b20b with cometic HG, arp head stud, block guard, ebay manifold with t3/t4 turbo, xs power wastegate with 13 psi spring, hks BOV, Rc 440cc injectors, clutch master fx400 and lightweight flywheel, walbro 255 FP, GM 3 bar map, and its tuned on hondata s200 at rev speed 559 in fresno. im not sure what is causing the lag everytime i shift gears, im in need of help please.

 

what rpm are you shifting at?

 

Might be a bad tune, my car bogs right before full boost ( my clutch was slipping on the dyno so I couldnt get a full tune so I just had it super richened up and it bogs down bad right before I hit boost )

 

it was tuned to redline at 6800 but i shift at 6400-6500 around there.

 

im not sure, but when it was first tuned it ran shitty cause when it starts to boost it chokes like it wasnt tuned at all so he told me that let it warm up first so i did and samething, then i left it for my tuner to retuned it again so he did, the first tune that he did push out 170 hp at 13 psi then the second tuned he did push out 245 hp same psi, so this time it ran a little better but it pulls and chokes pulls and chokes at 5500 rpm it doesnt pulls smoothly all they way redline. I thought that i might be the spark plugs and wires so i replace them with new ones and the spark plugs was 2 step colder now it ran a little better not what i expected from 13 psi and the lag about 2 second every time i shift into 2 all the way to 5th gear and i shift at 6400-6500 rpm. What i am disappoint on is that my cousins 240sx with a ka24de turbo street tuned at 11 psi stock motor and i can barely keep up with him and mine is tuned at 13 psi.

 

u running a 2" hot side IC piping..?

The more volume in the IC and piping, the more the turbo has to work to pressurize the lines and IC..

So huge FMIC's will create more lag as it has alot of volume to fill before getting into the boost

My street set up is 2" hot/2.5" cold

 

i have 2 1/4 inch pipe hot all around my intercooler is a trust intercooler made by greddy.

 

find another tuner.

 

maybe you need to shift at higher rpms...

 

it even lags at higher rpm. dont know who would be a better tuner i know that paris at stockton ca doesnt tune hondata ecu he only tune on crome.

 

There is quite a few tuners up around here me being one of them.

 

This sounds like a mechanical problem. The turbo could be dying. There are other ways for the turbo to die without necessarily destroying the rear turbine piston ring (or "seals" as everyone else here calls them).

Check for vacuum leaks and the turbo itself.

 

my turbo is a brand new turbo, we even try swaping out turbo too same thing.

 

hmmm.. that is interesting indeed.

 

im out of ideas now dont know what is causing it im just probably sell my turbo setup and go b20 vtec instead if i can get it to work right maybe somebody can get it to work on theirs instead but ill see first if i can get it to boost correctly then ill just sell it then. ill give ya some updates later.

 

haha. just go faster right?

hes already shifting at 6,500 rpms if hes not keeping boost or spooling at that theres something wrong.

 

im not sure if the cometic headgasket is the cause of it or the GM 3 bar map sensor is causing it but if you shift at low rpm about 5800 rpm then it doesnt lag but my car doesnt boost until 4000 to 4200 rpm but it doesnt pulls as strong when i shift at 6500 but the only thing is that when i shift at that high it lags only.

 

Yeh true, but its a "brand new ebay turbo" its hit or miss.

 

its in the the tune, it loads up real bad when RPM's drop and you gt back in the gas correct? Well any good tuner can fix that. It has nothing to do with the anything mechanical.

 

could also be going into a really low vacume range between shifts ive seen a couple cars that needed a extra row of vacume added to the map. mine did the same thing and this fixed it for me.