Turbo Lag help

[kinger]

Hi guys,

If you read my ride report in my garage you'll know I am officially an impulse turbo convert! Wow! Any way I have a minor issue where there is some lag (bog) when stabbing the throttle quickly, if you roll into it there is no lag. I think it may be tuning related. I also only got a 30 mile ride last year with only the 3" exhaust tunnel dump so I didn't have near enough ride time but I don't remember it being laggy at all, however it was loud as hell! So I added a boost activated exhaust cut out that opens at 6psi when its closed it routes into another 3" pipe with a baffle in it. I'm wondering if the crossover is some what related. I may pin it open and see if the lag disappears.

I also have a boost-it stand alone fuel injectors and controller system that activates and adds extra fuel at a certain boost threshold. Having it come on sooner made the lag worse and later made it better. I was going to keep moving it later but my AFR gauge started flaking out so I didn't want to change until I knew that was working.

Set up is 2860R with Tial housings and 3" v band, Tial external wastegate (also tunnel dump). Impulse race kit with 4 to 1 header and CPR intercooler.

Any other thoughts?

 

[mbarryracing]

... I also have a boost-it stand alone fuel injectors and controller system that activates and adds extra fuel at a certain boost threshold. Having it come on sooner made the lag worse and later made it better. I was going to keep moving it later but my AFR gauge started flaking out so I didn't want to change until I knew that was working.

That kinda leads me to think the lag is from a rich bog and not turbo related... Flogging it with too much fuel at the stab of the throttle until the boost comes up and starts flowing air to match?

 

[kinger]

Yes it feels different then traditional lag. I'll try a new AFR sensor and keep moving that threshold out or reduce fuel once its starts. Just wasn't comfortable doing that on the maiden voyage with a flaky AFR gauge.

 

[mbarryracing]

Oh I wouldn't either. What AFR gauge are you using?
Does that Boost It have an accelerator enrichment circuit?

 

[kinger]

Its the AEM with typical bosch sensor. I can only get the sensors to last around a year I was hoping with the midmount and sensor at the proper angle it would be better but like I said it could be my valve is causing the swirl in there. The boost it does not have the accel enrich circuit. It has the threshold for kicking in and then the main fuel. You can trim it at any RPM though. So it logs the AFR against each RPM and I can take out or add specific fuel at each RPM to dial it in. Last I checked I had some negative values on the lower RPMS (7K ish) meaning it was a little rich.

 

[06 apex yamcharger]

Put a NTK sensor in it part #24320 these sensors will last even running with race fuel in it. Its the only sensor that will last

 

[kinger]

Thank you sir! I have been frustrated with the sensors. No calibration needed when switching? Thanks a ton!

 

[06 apex yamcharger]

no it calibrates when u start it

 

[alpineviper]

Hi guys,

If you read my ride report in my garage you'll know I am officially an impulse turbo convert! Wow! Any way I have a minor issue where there is some lag (bog) when stabbing the throttle quickly, if you roll into it there is no lag. I think it may be tuning related. I also only got a 30 mile ride last year with only the 3" exhaust tunnel dump so I didn't have near enough ride time but I don't remember it being laggy at all, however it was loud as hell! So I added a boost activated exhaust cut out that opens at 6psi when its closed it routes into another 3" pipe with a baffle in it. I'm wondering if the crossover is some what related. I may pin it open and see if the lag disappears.

I also have a boost-it stand alone fuel injectors and controller system that activates and adds extra fuel at a certain boost threshold. Having it come on sooner made the lag worse and later made it better. I was going to keep moving it later but my AFR gauge started flaking out so I didn't want to change until I knew that was working.

Set up is 2860R with Tial housings and 3" v band, Tial external wastegate (also tunnel dump). Impulse race kit with 4 to 1 header and CPR intercooler.

Any other thoughts?

Did you ever get this figured out ?

 

[Mountaintech]

Did you ever get this figured out ?

He crashed it 2 weeks after his last post.

 

[kinger]

He crashed it 2 weeks after his last post.

Correct and the SW has been a disaster. Dearly miss that sled!!