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TD GAP large turbo feedback

I’ve read all through this thread and your comments/statements. I’m probably one of the first to run the GAP big turbo and in my third season . I highly suggest you talk to your tuner and get your issues worked out . With the big turbo #*$&@ can go bad quickly especially with boost creep .
NYturbo I'm with you on taking to your tuner to figure out whats going on. I also was one of the early on guys to go with the big turbo and it has been nothing short of awesome. The boost spikes that farmererz24 is getting are scary and have to be addressed before that motor is chunked.
 

86140562-5B8D-48D2-8C29-FB2A474EBA61.jpeg

Welded this up today. Should fix the boost creep issues this kit has.
 
A
NYturbo I'm with you on taking to your tuner to figure out whats going on. I also was one of the early on guys to go with the big turbo and it has been nothing short of awesome. The boost spikes that farmererz24 is getting are scary and have to be addressed before that motor is chunked.Are y

Are you guys running the stage 6 cams also? I’m told this is a phenomenon of the stage6 cams and gap turbo with high flow muffler. The stock muffler would fix the issue I am told but I would rather run my 3 inch high flow.
 

TD 998 big turbo upgrade recommendations​



TD GAP big turbo / TD MOD stock hardware requirement list: 250-550HP
1-TD Multimap ECU reflash
2-TD Flasher or Copitrail (allows flashing of ecu tuning and datalogging if equipped with option)
3-Closed Loop (keeps sled running optimal air fuel for better economy, better power consistent performance and improved response.
4-Map sensor upgrade (4 bar) (allows ECU Reading above 17 psi of boost)
5-1050cc Injector Dynamics kit
6-TD wideband o2 Kit (needed for Closed loop operation, it reads air fuel ratio)
7-TurboSmart Blow off valve
8-Fuel pump upgrade
9-Adjustable fuel regulator upgrade
10-TD Cold air OR Gap Ram air (gap ram air more power for race sleds
11- Dalton Clutch weights for power level under 350HP or Tapp Clutch for power level over 350HP (STM clutch weight also works)
12-Torsion conversion kit or STM secondary clutch for power over 350HP
13-retainer and spring upgrade for cylinder head (high rpm reliablility) as the big turbo makes power at 9200-9600rpm you need those.
14-Big 4 wheel kit. This is safety thing, the extra power will for sure not work with only the factory two plastic wheels in the back.
15-For Power level over 400HP is mandatory to upgrade to Carrillo rods at the very least. We have a lightweight set or a regular set. We also recommend doing the forged pistons if going above 430HP with a maximum compression ratio of 9.0 to 1. You can upgrade your Pump gas power limit by going with a lower compression piston set (we have that in stock) of 8.5 or lower. This will allow more boost and power on pump 91 octane fuel. For race sleds stick with 9:0 compression.
16-For power levels above 360HP we strongly recommend our HD head gasket with HD head studs

recommended upgrades:
1- TD stage 6 camshafts (keep in mind with TD Stage 6 minimum boost is 26 psi on the TD GAP big turbo kit). The TD mod stock will work fine with TD stage 6 at lower boost level and on pump gas. Therefore if you plan to trail ride the TD GAP big turbo it's better not to run the TD Stage 6 unless you plan to run a mix of race fuel with the pump gas as min boost of 26 psi requires high octane.
to review do not use TD stage 6 if you plan to run the TD GAP big turbo kit on the trail on pure 91 octane (you can use 91 + c16)
Stock cams are best for 91 octane pump gas trail use on the TD GAP big turbo kit

For the TD mod stock you can run a TD Stage 6 or stock cams no problem at any boost level.
2-TD Super cooler kit:
Improves HP greatly and also a much more consistent performance and Pull that never stops (cooler intake temps and less knock)
3-TD header
Much more power than stock manifold
More power on pump gas at same boost level
4-Datalogging option for the TD flasher or Copitrail
 

TD 998 big turbo upgrade recommendations​



TD GAP big turbo / TD MOD stock hardware requirement list: 250-550HP
1-TD Multimap ECU reflash
2-TD Flasher or Copitrail (allows flashing of ecu tuning and datalogging if equipped with option)
3-Closed Loop (keeps sled running optimal air fuel for better economy, better power consistent performance and improved response.
4-Map sensor upgrade (4 bar) (allows ECU Reading above 17 psi of boost)
5-1050cc Injector Dynamics kit
6-TD wideband o2 Kit (needed for Closed loop operation, it reads air fuel ratio)
7-TurboSmart Blow off valve
8-Fuel pump upgrade
9-Adjustable fuel regulator upgrade
10-TD Cold air OR Gap Ram air (gap ram air more power for race sleds
11- Dalton Clutch weights for power level under 350HP or Tapp Clutch for power level over 350HP (STM clutch weight also works)
12-Torsion conversion kit or STM secondary clutch for power over 350HP
13-retainer and spring upgrade for cylinder head (high rpm reliablility) as the big turbo makes power at 9200-9600rpm you need those.
14-Big 4 wheel kit. This is safety thing, the extra power will for sure not work with only the factory two plastic wheels in the back.
15-For Power level over 400HP is mandatory to upgrade to Carrillo rods at the very least. We have a lightweight set or a regular set. We also recommend doing the forged pistons if going above 430HP with a maximum compression ratio of 9.0 to 1. You can upgrade your Pump gas power limit by going with a lower compression piston set (we have that in stock) of 8.5 or lower. This will allow more boost and power on pump 91 octane fuel. For race sleds stick with 9:0 compression.
16-For power levels above 360HP we strongly recommend our HD head gasket with HD head studs

recommended upgrades:
1- TD stage 6 camshafts (keep in mind with TD Stage 6 minimum boost is 26 psi on the TD GAP big turbo kit). The TD mod stock will work fine with TD stage 6 at lower boost level and on pump gas. Therefore if you plan to trail ride the TD GAP big turbo it's better not to run the TD Stage 6 unless you plan to run a mix of race fuel with the pump gas as min boost of 26 psi requires high octane.
to review do not use TD stage 6 if you plan to run the TD GAP big turbo kit on the trail on pure 91 octane (you can use 91 + c16)
Stock cams are best for 91 octane pump gas trail use on the TD GAP big turbo kit

For the TD mod stock you can run a TD Stage 6 or stock cams no problem at any boost level.
2-TD Super cooler kit:
Improves HP greatly and also a much more consistent performance and Pull that never stops (cooler intake temps and less knock)
3-TD header
Much more power than stock manifold
More power on pump gas at same boost level
4-Datalogging option for the TD flasher or Copitrail
Yes, I’ve seen that. This is why I am installing a external gate to fix overboosting as clearly the stock internal gate is no longer sufficient…..
 
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External gate fixed all of the boost spike issues. Seems like this kit should come with an external gate considering the $$ this kit costs. Why does it have a “minimum 26psi” that you have to run? Cause the internal gate is insufficient?
 
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External gate fixed all of the boost spike issues. Seems like this kit should come with an external gate considering the $$ this kit costs. Why does it have a “minimum 26psi” that you have to run? Cause the internal gate is insufficient?
Any logs u can share and pics of your final install ?
 
Any logs u can share and pics of your final install ?
This was just wastegate pressure. Tomorow we will hook up the 2 port solinoid and try for 17psi. This should help allieveate the rpm drop after initial shift out.
 

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Waste gate pressure or valve % ?
The nipple on the turbo outlet was connected directly to the wastegate for this run, bypassing the stock ecu solinoid valve

Do you have the stage 6 cams and large turbo also?
 
The nipple on the turbo outlet was connected directly to the wastegate for this run, bypassing the stock ecu solinoid valve

Do you have the stage 6 cams and large turbo


No cams and not TD . I'm not seeing these issues. But I'm always interested in this sort of thing.
 
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I'm not running the Stage 6 cams either. I was curious about adding an external gate myself.....send another log of a wide open run if you can....this is good info!!
 
I will get another log. Currently chasing another issue where the 4 bar map sensor is reading a higher boost than what the gauge is showing. (15 gauge shows 30 on the log which then appears to activate boost cut ). Tune is for a 4 bar map.

Once I get the map sensor issue figured out I will post a log
 
Are you getting any codes with the map sensor reading incorrectly? I had issues with my 4bar sensor and it was due to moisture....parking my sled in heated garage would cause moisture in the tubes and get in the sensor causing all sorts of issues.
 


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