P400 Compression Ratio
Ok since I have all of you guys on the same page (sort of) about CR does anyone have any suggestions on the best way to obtain a 19:1 CR on a new P400 6.5 engine? Is there only two ways to do this as of this date? Machine piston crowns or machine the block deck? If I intend on running an HX 35 @ 20 to 25 lbs of boost do I need to go to 18:1 CR? How much efficiency and or fuel mileage will I loss going with 18:1? I feel that with the envelope being pushed and the present day and future improvement of the DB2 and or the DB4 pumps that it will be much easier to increase boost pressures (than change CR) to match fuel input by tuning the turbo (such as changing turbine and compressor wheels & housings) and the HX 35 has many different choices to increase air charge much further than the 6.5 structural integrity can withstand, even the P400. Or even better if you could fit a 351VGT with a Fleece controller on one of these would be even better but I'm not sure that could be made to fit in a DD and retain the A/C and Heater assembly. I guess the platform and use has alot to do with the settup like Robscarab says, a half ton grocery getter could probably run 20lbs of boost with 20:1 CR in a P400 but my 3/4 ton 4X4 Suburban towing will probably need the 18:1 CR if I want it to live. I guess I am just looking for verification of what I am allready thinking by some of you others with a little more experience with these motors than I and or any info on any 19:1 CR pistons that I don't now about or should I really just go with the 18:1 s for longevity? I have a size 13 shoe and two 5.9 Cummins 12 valve trucks and one 5.9 common rail (all 3 turned up) so I'm sure when I step out of one of those into my Burb it's going to be real hard to have a lite foot. Oh and after seeing that dodge IC in one of these I'm thinking of replacing my spearco with the dodge mounted behind the grill but I'm not sure the gains will be worth the expense, we'll see when I get my grill off, but my Burb is big and black and needs all the A/C it can get so I'm not sure I want to cut down the condenser.
I appreciate any and all comments and opinions
Thanks, Dave
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