What are your shift points and shift extensions?
Got a datalog?

 

nothing about your build seems like a mis-match of parts. By saying that you didnt notice a loss with cat converters; was that seat of the pants, or a dyno/track times? I'm one of the few that like the larger converters. At a certain point you tinker with the tune, shift points, launch technique, timing, weather, weight, traction etc to squeeze out a few tenths instead of continuing to throw parts (money) at it.

What altitude are you at? That could play a huge factor in a N/A application.

 

i am unaware of what a shift extension is. But I shift into 2nd at 7,000. And to 3rd at 6,800.
it’s hard to say if my truck got effected with the cats because when I did that I cut some weight out at the same time. The cats weren’t something I wanted. Just had to to keep it on the streets.

Boise is the closest track I have and it’s at 3400 ft for sea level. I think temps where in the mid 70’s that night.
the first converter I did was flashing at 4300 and I was only able to get a 1.94 60’ in Vegas at 2200 ft sea level. So I sent it back and had them re do it and now it flashes at 4650-4700 and I picked up over .2 with that set up in higher altitude.

 

Shift extension is pretty much your rpms drop between gear shifts.
If your shifting at 7000 do the rpms fall to 6000 or 5000?

 

Ohh I forgot I actually did the suncoast 6 pinion planetary too. Between the 1.9 and the 1.7.

When I make it back out to Vegas I am hoping to cut into the the mid 1.6’s. Like a 1.67 would be great. I just feel like the truck should have a higher MPH. I dyno’d 418 hp AWD in Utah at 4300 foot sea level and 103 degree shop.

 

it’s been awhile but if I remember correctly with that 6 pinion set up I drop like 6-700 rpms?

 

The 6 pinion deal doesnt matter in this aspect. Its the characteristics of the torque converter and engine power.

 

Are you aware of what the 6 pinion does? Because that changes absolutely everything. That’s what put my gears closer.

 

Yes im well aware of how gear ratios are changed. But that is what it is, the torque converter is what is in question here.
Ive had trucks perform better in the 1/4 mile with less shift extension and others do better with more shift extension.
Thats why i was asking how it was behaving.

A similar cam in a LS3 still shows power up to 7200.
But im not familiar with the patriot heads you have.
On every 6.0 id suggest Rectangle port heads they flow very good for a play toy just not so much for a low rpm towing engine.

 

A lot of us on this forum have the luxury of sea level tracks, or near sea level. I think the altitude is playing a big factor on your times. patriot has a nice CNC program. I wouldnt replace any parts. play with the finer details to gain time at this point unless you're ready to make the jump to nitrous or boost.