Long story short, I upgraded to an RCD 75 atmo and didnt gain any MPH at the drag strip.
Longer version: I've been running my truck at the drag strip after almost every set of mods just to track progress. I managed a 12.8@106mph on stock turbos fuel and front suspension. Eventually went 4-linked with an RCD 75mm and truck progressively got slower each outing to the track. I started watching rail pressure and it was dropping to around 22k. Figured injection pump/HPFP was tired after 180k original miles. I did put a fuel PSI gauge on the fuel cooler test port and it was holding 4 PSI at WOT, with the LPFP being internally regulated to 3psi it seemed good to me. So I decided a new HPFP was in order.
Last weekend I installed a new reman HPFP. Ran at the track yesterday with new Nitto 420(was previously on 33" AT's) and while I got my best time ever(12.55), my MPH was only back up to 106mph. Watched rail pressure and it held 24,500-25k the whole run. But boost is only maxing around 44PSI. On the street i've seen 52psi. Several guys helped me look for boost leaks, I built 10PSI while they looked and could not find anything. No obvious boost or exhaust leaks(downpipe leaks a small bit, but shouldnt matter?).
List of mods:
Studded with OEM gaskets
SDP Ceramic coated up-pipes
SDP 4" ceramic coated downpipe
Ceramic coated OEM 6.4 manifolds
Rudy's Diesel CAC pipe
No Limit Intake
RCD 75mm stock-appearing atmo
New OEM HPFP
BTS Built 5r
PMF Front 4-link
PMF Rear bars
Bull**** removed
MPD CCV re-route, vented to atmo
I dont have a wastegate yet, but am working through that with a vendor. Ordered a kit and couldnt get it to fit. Will be going on ASAP.
Along with a host of OEM replacement parts fairly recent and along with stud job 40k ago.
Truck runs great, and with the new turbo it felt alot stronger on the street. I was very disappointed and surprised when it ran 2-3mph slower at my first outing after the turbo, and only returned to factory MPH with new HPFP. If I didnt know any better, and hadnt been tracking progress i'd be thrilled. But unfortunately i've been keeping track. Truck weighs in at 7600lbs, am I expecting too much for my mods? Is something still wrong that I need to track down? I'm thinking about a new low pressure fuel system, as i'll need it for dual fuelers eventually anyways.
So whats next, LPFP, injectors, dual fuelers? 59HP turbo?
Longer version: I've been running my truck at the drag strip after almost every set of mods just to track progress. I managed a 12.8@106mph on stock turbos fuel and front suspension. Eventually went 4-linked with an RCD 75mm and truck progressively got slower each outing to the track. I started watching rail pressure and it was dropping to around 22k. Figured injection pump/HPFP was tired after 180k original miles. I did put a fuel PSI gauge on the fuel cooler test port and it was holding 4 PSI at WOT, with the LPFP being internally regulated to 3psi it seemed good to me. So I decided a new HPFP was in order.
Last weekend I installed a new reman HPFP. Ran at the track yesterday with new Nitto 420(was previously on 33" AT's) and while I got my best time ever(12.55), my MPH was only back up to 106mph. Watched rail pressure and it held 24,500-25k the whole run. But boost is only maxing around 44PSI. On the street i've seen 52psi. Several guys helped me look for boost leaks, I built 10PSI while they looked and could not find anything. No obvious boost or exhaust leaks(downpipe leaks a small bit, but shouldnt matter?).
List of mods:
Studded with OEM gaskets
SDP Ceramic coated up-pipes
SDP 4" ceramic coated downpipe
Ceramic coated OEM 6.4 manifolds
Rudy's Diesel CAC pipe
No Limit Intake
RCD 75mm stock-appearing atmo
New OEM HPFP
BTS Built 5r
PMF Front 4-link
PMF Rear bars
Bull**** removed
MPD CCV re-route, vented to atmo
I dont have a wastegate yet, but am working through that with a vendor. Ordered a kit and couldnt get it to fit. Will be going on ASAP.
Along with a host of OEM replacement parts fairly recent and along with stud job 40k ago.
Truck runs great, and with the new turbo it felt alot stronger on the street. I was very disappointed and surprised when it ran 2-3mph slower at my first outing after the turbo, and only returned to factory MPH with new HPFP. If I didnt know any better, and hadnt been tracking progress i'd be thrilled. But unfortunately i've been keeping track. Truck weighs in at 7600lbs, am I expecting too much for my mods? Is something still wrong that I need to track down? I'm thinking about a new low pressure fuel system, as i'll need it for dual fuelers eventually anyways.
So whats next, LPFP, injectors, dual fuelers? 59HP turbo?
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