Whipple 5.7 Ram cam timing

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09-20-2019
jhodges275

1 Attachment(s)

Whipple 5.7 Ram cam timing

I've done a ton of research on here and read a lot of good info on cam timing from several the hemi tuning veterans but.....I still don't really know where to go with my tune. I have a 2016 Ram 5.7 (completely stock long block) with 1.75" longtube headers, high flow 3" cats, 2.9L Whipple with stock 3.625 pulley. Also running 750ml/min (actual measured amount) water/meth injection pre throttle body. I'm hitting 10.5-10.75 PSI with meth through the blower and 8-9 PSI without meth. The truck made approx. 550 WHP/550 WTQ on the dyno when I had it dyno tuned. I have since started tuning my own vehicles (mainly this one) and I have made a lot of drivability changes and also cleaned up the fueling some since the dyno tune. I am running .77-.78 Lambda at WOT throughout pulls. My main question is, what should I do with the cam timing to help performance with the addition of the blower. The cam timing is still completely stock which I know is probably less than ideal with the added boost. On the dyno the truck continued to make power until almost 7K RPM (just to see), although I shift around 6250 normally. I have read a ton of good stuff specifically from Hemituna and 06300CSRT8 so I would really appreciate it if some of you guys could point me in the right direction. I will attach my current tune for critiquing. In my logs, the Exhaust Cam Angle runs advanced at around 128* at idle and very light throttle. At highway cruising speeds it appears to be fully retarding at 90* which seems strange. During a WOT pull it does follow the WOT table though.
Attachment 93285
09-20-2019
Homer

I am in the same boat as you. I just swapped out my 5.7 cam with a 6.2 cam (very inexpensive mod but a significant amount of wrenching). Looking at how the hell cats swing the cam you can tell there is a big difference (WOT is more of a step function) when compared to a 5.7/6.4. Even though the 6.2 cam spec is similar to the 6.4 but with more exhaust duration and slightly different lift. For now I just pulled the VTT tables into my tune but I am pretty sure it is not ideal but good enough until I hit a dyno.

Anyways I know that tweaking the cam can help with the light switch effect during PT but other than that I lack the intuition/fundamentals (would love to find a book that can shed some light) as to what changes to implement for forced induction applications using an "NA cam". I think this is where experience comes into play and I totally get why folks might not be willing to share.

Explanations like these are extremely beneficial.
https://forum.hptuners.com/showthrea...l=1#post458478
09-21-2019
jhodges275

1 Attachment(s)

So I made some changes to my cam timing following Hemituna's example in the post below. I literally copied over the cam timing settings for the Whippled 6.4 and subtracted 5.5* to account for the difference in LSA between the 6.4 cam and the 5.7 cam (120.5*-115*=5.5*).

https://forum.hptuners.com/showthrea...ght=cam+timing

I also made my PT table match the WOT table and like Hemituna said and it definitely smoothed out any surging on part throttle boost. I am not tuning on a dyno so I can't actually see if it picked up any power or not but it did feel strong throughout the entire RPM range (but it did before too). When comparing logs of third gear pulls before and after the cam timing changes, I did notice that my aircharge in higher RPM's was actually higher before making the changes. After the changes, I am running more advance in the higher RPM's than before so I'm guessing I may actually need more retard. Please let me know your thoughts and if comparing aircharge is a viable way to see if the changes are helping or hurting.
Attachment 93303
04-10-2020
Homer

Quote:

Originally Posted by jhodges275

So I made some changes to my cam timing following Hemituna's example in the post below. I literally copied over the cam timing settings for the Whippled 6.4 and subtracted 5.5* to account for the difference in LSA between the 6.4 cam and the 5.7 cam (120.5*-115*=5.5*).

https://forum.hptuners.com/showthrea...ght=cam+timing

I also made my PT table match the WOT table and like Hemituna said and it definitely smoothed out any surging on part throttle boost. I am not tuning on a dyno so I can't actually see if it picked up any power or not but it did feel strong throughout the entire RPM range (but it did before too). When comparing logs of third gear pulls before and after the cam timing changes, I did notice that my aircharge in higher RPM's was actually higher before making the changes. After the changes, I am running more advance in the higher RPM's than before so I'm guessing I may actually need more retard. Please let me know your thoughts and if comparing aircharge is a viable way to see if the changes are helping or hurting.
Attachment 93303

Shouldn't the offset be 9 degrees in the tables?
https://forum.hptuners.com/showthrea...l=1#post587987