Mhd stage 2 Noticeable Lag??

[Supra Jr.]

Unlocked and running stage 2 93 and the car is so much better, but I noticed now just from a dig when racing that there is now a noticeable 1 second lag then bam it pours on like crazy?? It gives the other car especially N/A a nice head start while you wait for it to poor on. Guess this is just turbos?? I never owned a turbo before, came from a C6 vette and a roush supercharged mustang. Also on my Mhd app it says I'm hitting about 23.9 boost max, is that OK on 93??

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[Mason]

Stock turbo? Shouldn’t really lag

 

[Supra Jr.]

Stock turbo? Shouldn’t really lag

It does now just from a dead stop.

 

[zrk]

It does now just from a dead stop.

Then you're not loading the car. You just sitting there then pressing the gas?

24 PSI is a lot for 93, and it's definitely at the limit of what the stock turbo is capable of.

 

[Supra Jr.]

Then you're not loading the car. You just sitting there then pressing the gas?

24 PSI is a lot for 93, and it's definitely at the limit of what the stock turbo is capable of.

Yes exactly, I'm just punching the throttle which I thought was the problem, and yes on the mhd app it holds your highest boost made and it always says 23.9. Do you think that maybe it's just spikes?? Should I look into it?? It's just really my weekend toy and obviously racing here and there but nothing radical like you!! So should I get it checked out or do you think it's fine ZRK? I mean a ton of people have this tune and I'm sure it's fine? I also have a AA catted downpipe and just a MST intake and nothing else.

 

[zrk]

Yes exactly, I'm just punching the throttle which I thought was the problem, and yes on the mhd app it holds your highest boost made and it always says 23.9. Do you think that maybe it's just spikes?? Should I look into it?? It's just really my weekend toy and obviously racing here and there but nothing radical like you!! So should I get it checked out or do you think it's fine ZRK? I mean a ton of people have this tune and I'm sure it's fine? I also have a AA catted downpipe and just a MST intake and nothing else.

Take a log and upload it to datazap.me

Try to launch the car.

0. Sport Mode
1. Tap Traction Control - (turn off traction)
2. Hold Traction Control - (turn off VSC)
3. Switch to manual mode
4. Burnout in First gear in the water box
5. Approach staging lights
6. Shift to 2nd
7. Attempt to push the brake pedal through the floor with your LEFT foot
7a. Pump Brake Pedal HARD
8. While holding the brake pedal down, bring RPMs up to ~2k RPMs quickly (you'll feel the car "squat"), this is the torque converter loading. Boost will climb.
9. On Green - Mash gas & release brake
10. Shift when you see the indicator reach 55-5600 RPMs (stock turbo)
10a. Don't shift out of 5th, ride it through.

Pushing much harder than 2200 RPMs loading up the converter is a sure-fire way to snap an axle after a couple of passes, and it's 3-4 months for a DSS axle. Careful.

 

[razorlab]

That peak pressure is probably from the shift spikes since it’s logging pressure pre throttle plate. Does it hit that high when you just do a single 4th gear wot pull with no shift?

 

[Supra Jr.]

That peak pressure is probably from the shift spikes since it’s logging pressure pre throttle plate. Does it hit that high when you just do a single 4th gear wot pull with no shift?

Don't know would have to go out somewhere and get it in 4th gear and reset the app first

 

[Avarela99]

That peak pressure is probably from the shift spikes since it’s logging pressure pre throttle plate. Does it hit that high when you just do a single 4th gear wot pull with no shift?

This^

On my car between shifts it shows crazy amounts of PSI sometimes between shifts on my logs also even with the OTS map. If you are running a pump gas OTS map you have little to be worried about that tune is conservative and well tested by MHD at this point. It's a solid, reliable, and smooth bump in power. Also I recommend switching to catless you can just delete the CEL permanently now.

 

[Supra Jr.]

That peak pressure is probably from the shift spikes since it’s logging pressure pre throttle plate. Does it hit that high when you just do a single 4th gear wot pull with no shift?

So I went out like you said and did just 4th gear pulls with no shifting. First pull I saw 31.8 but I must have spun or something, after that I did about 3 more solid 4th gear pulls with keeping my eyes on the boost gauge and didn't go above 20lbs!! Thank you for telling me how to check!!

 

[Supra Jr.]

This^

On my car between shifts it shows crazy amounts of PSI sometimes between shifts on my logs also even with the OTS map. If you are running a pump gas OTS map you have little to be worried about that tune is conservative and well tested by MHD at this point. It's a solid, reliable, and smooth bump in power. Also I recommend switching to catless you can just delete the CEL permanently now.

Wouldn't mind catless but don't really want to spend the little more amount of money for another downpipe and install with that smell for about 15hp or so. The AA catted will have to do. Also thanks for the info and making me feel better!!!!

 

[zrk]

You're likely measuring chargepipe boost and not manifold boost. You'll get egregious spikes when the throttle blade closes.

 

[zrk]

That peak pressure is probably from the shift spikes since it’s logging pressure pre throttle plate. Does it hit that high when you just do a single 4th gear wot pull with no shift?

Oh whoops, you said that.

 

[Supra Jr.]

You're likely measuring chargepipe boost and not manifold boost. You'll get egregious spikes when the throttle blade closes.

With how much power or boost should you really worry about changing out the charge pipe,??

 

[Coqui]

I did some mhd stage 2 93 oct logs and had Fabian/pure.boost look at them. 4th gear pulls I was hitting roughly 21psi max. He said it looked good, abit of timing correction likely due to the 93oct I used. I eventually changed to different gas station but now running e40 ots tune which is a beast. Running nt555r2 on rear to control spin. Next is custom e50

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