Throw rocks for all I care, here is what is going on my Titan. I have a spare one around the house, gave up on getting Uprev to fix the damn throttle map, so this is how I am going to make my truck reach its 12.6:1 afr targets despite what I bolt on it. The only tuning I have on my heads/cam/header/intake 4.7 Dakota at the moment is a Split Second PSC1-003.
On the Titan the afr is actually not too bad on my latest runs. The timing, cam phase, throttle opening is all about perfectly optimized with Hypertech so why fight something that works and is already into the 13s at the track. It ran a richest reading of 11.6-11.8 @ 6,000 rpm and never leaner than 12.2:1 except during the 1-2 shift when it closed the throttle some it had a rich dip, followed by a slightly leaner 12.6 area when the throttle opened again. My long term fuel trims are about -6% so I know its a little rich. A slight reduction in MAP voltage should do the trick well. I also noticed that the stock exhaust piping with my 24" magnaflow reduced my gms/sec reading from a peak of 301 to only 289. No wonder I feel a high rpm power reduction with the stock 1.97" ID pipes. With the stock tail pipe section being around .080" wall thickness it is also only 2.34" ID where the muffler exits into the stock tail pipe. I bet I lost 15+ HP @ 6,000 rpm with the stock piping compared to even my crush bent 2.5 to single 3" system. I noticed gibson had a very nice 2.5 to single 3" setup on sale for around $350. My one hold back on that system is I really want to run single 3.5" after the Y but at the $350 price, mandrel bent ready to bolt on, its hard to resist.
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Just FYI....I do not expect to gain much from this mod as I doubt that going from 11.8 to 12.6:1 afr is going to net more than 5-8 RWHP, but the ability to adjust the air/fuel ratio for the install of my headers and other mods is my goal.
On the Titan the afr is actually not too bad on my latest runs. The timing, cam phase, throttle opening is all about perfectly optimized with Hypertech so why fight something that works and is already into the 13s at the track. It ran a richest reading of 11.6-11.8 @ 6,000 rpm and never leaner than 12.2:1 except during the 1-2 shift when it closed the throttle some it had a rich dip, followed by a slightly leaner 12.6 area when the throttle opened again. My long term fuel trims are about -6% so I know its a little rich. A slight reduction in MAP voltage should do the trick well. I also noticed that the stock exhaust piping with my 24" magnaflow reduced my gms/sec reading from a peak of 301 to only 289. No wonder I feel a high rpm power reduction with the stock 1.97" ID pipes. With the stock tail pipe section being around .080" wall thickness it is also only 2.34" ID where the muffler exits into the stock tail pipe. I bet I lost 15+ HP @ 6,000 rpm with the stock piping compared to even my crush bent 2.5 to single 3" system. I noticed gibson had a very nice 2.5 to single 3" setup on sale for around $350. My one hold back on that system is I really want to run single 3.5" after the Y but at the $350 price, mandrel bent ready to bolt on, its hard to resist.
Just FYI....I do not expect to gain much from this mod as I doubt that going from 11.8 to 12.6:1 afr is going to net more than 5-8 RWHP, but the ability to adjust the air/fuel ratio for the install of my headers and other mods is my goal.
