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I need to do the PCV relocation on my VG30DETT, but the only references I find on the 'net are cars that have had the modifcation, no how it's done. As near as I can tell I just move them to some high point in the valve cover. Does anyone have any pictures of this? Thanks in advance.

I would have to ask why you'd want a TH350 instead of a normal SR20DE automatic?

Maximum overall acceleration capability. Many people forget to account for that one! http://www.datsuns.com/projects/fv-s/design_notes2.htm The article talked about gearing taller to compensate, but the limit of available traction is discussed too Bottom of the page has charts that displays that dilemma. Just because you add 100ft-lbs of torque to the equation doesn't mean the car will accelerate any harder in 1st. If you're already traction limited, more power won't help until you get to a speed / gear that can get that extra power to the ground. Traction is why a 500hp & 700hp Z-car can have identical 0-60 times. If their available traction is identical (and roughly stock) the 700HP car will be faster only at higher speeds. 0-60 might be the same, but 60-100 won't.

You are correct in both counts, as long as you mean "a car will accelerate its hardest at its peak torque to the wheel". Until you're going fast enough for aerodynamics to start screwing things up, plotting your accleration curve will also plot your torque curve. This is how G-Tech and the like can give you a torque curve by using accelerometer. The chart below is from a VG30E. Note that this car will accelerate harder from 30MPH when it's NOT at it's *enigne's* torque peak. Gearing MUST come into play when calculating shift points and acceleration curves. RPM / TQ - gear - "TQ at wheel" 3500: 167 - 1.3 - 217ft-lbs [3rd gear about 35MPH] 4000: 160 4500: 160 5000: 155 5100: 153 - 1.9 - 290ft-lbs [2nd gear, same road speed as 3500 in 3rd] 5500: 145 6000: 135 When I wrote my article on my website, I was using "horsepower to the wheel" (confusing in retrospect) but came up with the same result.

I hate to tell you this, but you and I are largely saying the same thing: "Higher engine torque means more rear wheel torque. But so does lower gearing. You need to strike the proper balance between the two quantities." Exactly...and shifting when torque at the wheel AT THE WHEEL is the same value after the shift as before. "It is the twisting force at the rear wheels that determines how fast a car accelerates. " CORRECT - you just defined torque at the wheel. Now...calculate that with a horsepower number. You can't, you have to convert it to a torque value first. Related, but not the same. "Arrange your shift points so the engine HP before and after shift is the same. " EXACTLY! You will note when you do this math, the torque at the wheel is exactly the same! Same with HP! I ran into this years ago doing the math and first I was shocked, then I thought about it and went "DUH". "If you do the math you will find the car will accelerate the fastest when you shift into a whatever gear puts the engine at it’s horsepower peak." You are saying somthing different here. Again, do the math and you'll find the "engine HP before and after shift is the same" statement of yours is the correct one.

That spreadsheet was done a long time ago and I should redo it. What I need to emphasize is you need to know the torque at the rear wheel across a wide spread of RPM. The trick is to shift when value the torque at the wheels *after* the shift is the same at torque value before the shift. Sometimes this is not possible. Attached is a .GIF for demonstration...bear with me Crankhshaft torque x gear ratio x axle ratio x tire size = torque at the wheel. Given that the wheel size is constant (for the purposes of this topic) and the axle ratio doesn't change, all we care about is torque x gear ratio. In my example, the VG30ET here is making 290ft-lbs of torque@4700RPM. multiply it by 3.1:1 1st gear and we get a value of 899ft-lbs. Shifting at 4700rpm drops this engine to 3049RPM in 2nd (far right column). Torque in 2nd @ 3049RPM is 623ft-lbs (310ft-lbs at crank x 2.011 gear). Better not shift here, even though you're past your torque peak. working up the chart, at 6300rpm we get 629ft-lbs in 1st, shifting to 2nd puts us at 4100rpm and 627ft-lbs..you have your shift point - FOR THAT GEAR. If 3rd is 1.3:1 and 4th is 1:1, the shift points move lower by about 700RPM...so depending on the torque curve and trans ratios you will have different shift points for different gears. If the image isn't clear enough and/or you want the actual sheet or data I just worked from, let me know. NOTE: It gets confusing when you know that in any one gear, your car will accelerate the hardest at its torque peak (barring aerodynamics at higher speeds) ...some might think this means shift when you will end up at your torque peak once you've shifted, but this rarely works out. Bottom line: Torque at the wheel after the shift should be equal to torque at wheel before the shift.

I have a project that will be using a VQ35DE(TT) and I need to decide what transmission to use. I want my RPM's at 60MPH to be about 1900-2000. While the 6-speed seems natural (just select the axle ratio and be done with it), 6th in the 350Z trans is shorter (.79) than 5th in the Z32 box (.75). As the VQ has a wide torque curve the extra gear seems superfluous (read, it slows down stuff like 1/4mi times). What would be ideal is a 6-speed in which the first 5 are the same (or close) as the Z32 and then 6th be an even taller overdrive. Has anyone adapted a T56 to the VQ35?

Funny, the 510 has forward runing T/C rods and I moved mine to the S30 style of rearward facing - because the 240Z has a front rack and adapting it to the 510 involved making the T/C's rearward facing. All other factors being the same it is unlikely you'll feel any difference by simply having the T/C's run forward instead of rearward. As Jmortensen said, the *angle* of the T/C rod will make far more difference than weather it's forward or rearward facing.

The DETT is about 440lbs (N/A is 420) and the 5-speed is 120lbs.....carry the seven, divide by the width of my a**, add Thursday......I come up with 560lbs.

IMO it's simpler to get the TT - it has sodium-filled exhaust valves as well as enough other changes it's cheaper to pick up a complete DETT for ~$1100 than it is to convert your DE to DETT. Here's the link to TT.net differences:http://tinyurl.com/dnjdg

You forgot so soon? You don't remember the meeting was living proof that blind dates don't turn out the way you expect, I thought you're name was RONDA.... "You're a DUDE!?!?"

Thanks for that info. My DETT is tired and needs a rebuild, I do have an NA VG30DE and should pick up some TT heads so I can have a rebuild under way while keeping the current TT in the car. I have seen the TT.NET write up on NA/TT differences and it's a good one.

I don't think so Ron, he's in Maryland...

Cool, but no pictures?