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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?

What kind of tease is that? While yes it answer the question of if they're different it's vague as to the exact differences. What does "corresponding to the different needs for a Turbo application" mean? It's like saying "the cure for cancer is in this foreign language answer: 'pollyimainint frishet ben colqurir' " but not telling us what the translation is. Pictures would be great for those of us now knowing what that means without pictures and arrows.. Even w/out pictures this is better info than I've seen previously though, thanks!

The tach simply takes it's signal from the ECU - usually wire 7 if you have a scematic of the ECU. The transmission (Is it an automatic or a 5-speed?) should have an electronic sending unit as well, the '90-later 300ZX transmissions do. The VG30DET ECU should br running the "VVT" (NVCS in Nissan nomenclature). If you have a scematic for the VG30DET car you should be able to match it to the Z31 dash imputs. I have a similar swap (DETT) and I have a functioning tach but have not bothered working with the speedo (my older car dash uses cable and the trans has electronic output)

Ruschman pretty much covered what we did, very much like DRAX except we went with rearward TC's like the Z: http://www.datsuns.com/Tech/510_rack_conversion.htm I have since moved to Z31 front struts (technically 200ZX V6 struts but the same thing). My progession went form 240Z struts to 4-cyl 200SX struts (spindle angle is different between these two, and so is the hub the rotor mounts to), then to Z31 / 200ZX V6 stuff. The Z31 struts let us put Z32 brakes on the car with little other mods up front. I still have the extra 3" track using the 240Z crossmember gives me, not really an issue especially since I'm now running NA Z32 (16x7.5) wheels (in fact my car was never low enough for this to be an issue with any of the wheels I had up front - generic 15x7's. 280ZXT 15x6 swastika's, and the current ones). 240/60/80Z struts will work, 280ZX struts won't unless you build some adjustabale lower control arms to correct the camber. What would I do different? If I had to keep the struts (I hate struts) I wouldn't change a thing, I love the steering & brakes! Note some 240Z racks (like mine) are aluminum, others are cast iron. Same with Z32 brake calipers - '90-92.5 are aluminum calipers, all later are iron. Note '90 was the only year of the 26mm wide rotors up front. So 1990 will be the lightest Z32 brake upgrade, but I went with '91-'92.5 because I'm as concerned about being able to find replacement parts and a couple extra lbs of brake mass I can live with since I have nearly 400hp in a 2500# car. In sum, my current setup: Z31 struts, 240Z rack, crossmember and lower control arms (now adjustable), easy-to-fab camber plate/spring adapter to run the smaller diameter springs (now coilovers), bumpsteer spacers. This picture gives you a good idea of the current setup (except struts) http://tinyurl.com/9gy5o, and with a little work you can use the 510 strut tower caps and it will look factory! http://www.datsuns.com/red/2k5view5.jpg

Gary would you quit posting this stuff? I swear every time you post videos I get 5 guys sending the links to me, as if I'd be interested in a Z-car powered 510

Guys, I'm running a VG30DETT in my car and I currently have Bosch recirc valves set up as BOV's. I did this because I was unaware the Bosch valves CANNOT be used as a BOV because at idle / cruise these things DRAW air, so they need to be plumbed as recircs so the air they draw in is metered. In my case it'd be far easier to replace these with regular BOV's than to plum them as recircs. Does anyone have any recommendations on a BOV that would easily replace this? The Bosch has no flange so a BOV that connects the same way would be desireable. A picture of the Bosch valve is here: http://www.datsuns.com/Tech/BoschBOV.gif

I'm running factory turbos on my DETT and I have this same issue, is it possible to simply replace the wastegate with his Top End Performance piece Austin? It reads like it but I just want to be sure. Dave Lum VG30DETT powered Datsun http://www.datsuns.com