Tony D

That was why JeffP limited himself to simply extrude honing it and smoothing it out a bit. It was recognised it would be the necking point on his system, and is really restricting his output right now. He's only making 600Hp, so if you are shooting for more than that, to be sure the stock manifold will probably really prove to be an impediment.

Take a look at some of the newer Toyota Manifolds, they look just like that: a set of Tube Headers with a T/B stuck on the 'collector flange' and made of aluminum instead of steel.

Really, as long as you have a linkage with little or no play, the TPS can go just about anywhere in the system. Inside the car on the throttle pedal pivot point is nice and clean, and cool, and doesn't mean you have to open the hood to connect to it for troubleshooting. Only if your linkage breaks will it go kaflooey...and in that case you won't be moving anyway.

Oh oh, the word it out! Sarah the Webwatcher at Nissan Sport has us listed on her "Sarah's Hot Topics" on the Nissan Sport webpage. Well, I didn't admit anything illegal, I paid money to get on the track and have the speeds verified. The rest of you giving time deates and photos on the other hand.... Muahahahahaha!

Measure Twice, order once. Then assemble just to check again!

Yeah, my eyes are set on that R230 in the high 2's. With a 3.36 I can play with tire height to get a variety of gears, and then for the long course, the 2.9 setup can go in there for real long legs. Somewhere a 3.08 falls to mind, but 3.15 works as well I suppose.

Oh yeah, the week I got to turn in the company truck, a nice shell shows up.... DAMN! You are the devil, Eric!

When I hooked up mine for the MS, I used a 300ZX 3-wire, and wired it into the fuel pump relay circuit. It is only getting power when the fuel pump is running. I used the Z31 connector, and wired it according to the Z31 FSM wiring diagram, meaning the signal had a shielded wire back to the ECU, with the other two being power and dedicated ground. I will have to check into that current limiting resistor JeffP mentioned, I have never seen excessive draw, but it may be wise to limit current downstream by such a method. I hooked it into the Fuel Pump circuit because I only want power on it when it's running. If you were worried about power draw on existing circuits, it's simply a matter of putting another relay into the circuit, and using the fuel pump power wire be the one that triggers the 'heater circuit relay' you install with a direct line from power to the sensor (through whatever current limiting resistor you deem appropriate) and then on to it's own discreet ground.

I ran the small housing for years. On the auto-X I was at 17psi at 1700rpm at WOT. It was more like a supercharged car than a turbocharged cars. It was ALL DONE at 5500 though. Short shifting was a way of life. But for what it was, it worked fine. If I was gumptious, I would put a larger external wastegate for a separate bypass at higher RPM and use a larger compressor wheel...but you got to be careful with the smaller wheel working that big wheel. But yeah, for Auto-X it was a hoot.

The LeMons car used the 8X8 map from above. Instead of using the MSQ, take a look at the maps, and simply enter the values into your Megasquirt. It may not be a downloadable 'plug and play' but you can populate the maps really quickly, and even if the engine is not the 'same' there is great lattitude in the tuning...it will run, you just may need to run some tuning runs to clean it up where the peak torque area changed. Above there and below there, there is WIDE lattitude in the tuning and what will run.

OR, use an 'earlier' B-Box speedo cog carrier! The early and late B-Boxes have the same disparity, there are two carriers, each offset differently...but the 'difference' is simply that they rotated it 180 and made the hold down clamp there instead. Any B-Box cog holder can be made 'universal' for the B-Boxes (and will then fit the C-Box as well) by simply cutting the slot described above. Monzster is correct, there is a breakpoint where the KA tranny went from Speedo Cog, to an electronic speed pulser/sensor (this is what my 91 Tranny had in it). Curiously, these retrofit to later trannies and can be used on the electronic speedometers through their calibration function. Eliminate that speedo cable! Go electronic! The cogs fit into the speed sensor hole no problem...and curiously the speed pulser used the same drive as for the speedo cable. Meaning if you cut the slot in the speed sensor/pulser it will also become universal, fitting in any A/B/C box for an E-Speedo Conversion! I will go get the calipers now. It's been a hectic couple of day recently...corporate downsizing:-( I'll be right back...

Man, shades of Bubbles! LOL That sucks man. But those corners are sharp, and when you cut em, they BITE HARD! What can you do...live and learn, right? If you're going to have a failure, may as well make it a big one. You forgot your hood...

nigel, I have a 91 KA tranny, and did the "C to B Bellhousing Swap"---Remove C Bellhousing, and replace with the B housing after altering the opening of the shift rod to 15mm, and opening of the countershaft bearing to the larger "C" style countershaft bearing style. Move mounting X-Member back a bit, and shorten the driveshaft 50mm... Mine appeared to have some sort of 'hardened spacer' to make the gearset wider than the B box I replaced. I do have one of each (B and C) available on the back porch still disassembled awaiting bellhousing mods, so I can measure with my caliper in the morning and post back to this thread. They have been doing this swap in Japan for years actually. Some speed shops sell the bellhousings (around $600 equivalent) already modified, though the japanese technique usually revolves around a complete disassembly of the gearset to swap the shiftrod out with a special one that has a turned-down end for the earlier bellhousing section. IMO altering the bellhousing holes is easier, as the swap becomes very quick that way!

That's not quite apples and apples there. The water analogy assumes the water flow is optimized at 10psi and you open up the pipe. In the exhaust system the exhaust gasses are restricted quite a bit, and their flow is nowhere NEAR optimized in the current passages. And regardless of all that, the turbo manifold dumps into the turbine housing, the most restrictive part of the whole system. It's exactly opposite of the 1" to 2" analogy. It's more like dumping a 2" pipe to a .375 Jet Nozzle! What he has accomplished is making his US Spec Manifold flow more like the Euro Turbo manifold. If you have ever seen the Euro manifold, the runner towards the front is more than 1 5/8" in diameter (meaning larger than the SFP Tubular Manifold some have!) and the step on the turbo inlet flange is eliminated completely compared to the US 2.8 and JDM 2L specification manifolds. The only difference between the 2l JDM turbo and the 2.8l US Spec unit is the A/R on the turbine is .48 as opposed to .63. THAT will make FAR more difference on the spool characteristics of the engine than the removal of restrictive manifolding. As long as that turbine A/R is that small, the exhaust manifold will not be the primary 'velocity device'. The Euro Turbo cars have .82 A/R, with the derestrictive manifold, and 200HP rated power. I have run both the JDM and US Spec turbine housings on a US manifold, and the spool changed noticeably. But cutting the manifold open only helped on the top end, I noticed nothing on the bottom end. Meaning the spool was the same (boost threshold), but the engines seemed much more willing to rev beyond the original 5500rpms of the stock manifold.

Tell all that to Porsche, and remind Corky Bell he's also in error, Clifton. I imitate only the best. Prespinning of the compressor side is easily done with tangential entry of the BOV through an appropriately designed duct. Porsche has done it for years. And Corky's systems all had a bypass setup to assist those older turbos to lower boost threshold by removing incipient spinup loadings by bypassing around the compressor while in most N/A operation loadings. If you saeriously think well over 3 square inches of air DIRECTLY bypassing the air filter is not something that is requiring of a filter, then have at it. Remember air takes the path of least resistance. It will flow through an open bypass valve before the filter media...it's a bit more than 'an open vacuum line' if the thing is 1/2 open and even a small one at 19 to 25mm discharge opening. IMO, that's a considerable air leak past your primary filtration.

Yeah, a bypass valve is actually designed to remove load on the turbo during incipient spin-up, and close as manifold vacuum nears 5" Hg or thereabouts. They will open at any sort of lift throttle to keep the turbo spinning fast, ready for reboost. This is how mine was set up on the 73 ZT, and I really liked it. I had a separate recirc hose that had a small K&N filter on it, before finally getting one of the big 3" Cones and 3" inlet pipe to allow a proper recirc line that blew into the turbo inlet to prespool the impeller wheel and connecting it to that instead. In either case, you need some sort of filtration on the bypass valve if you have it open at idle. If you recirc it, take the time to do it right and aim the blowdown to prespin the compressor wheel properly instead of simply dumping in the inlet piping to the turbo---all that does it create flow disturbances.

In preparation for MSA this year, I had to move some cars. The red 260ZT project I had hoped to get going last year had literally sat for a full year without being touched. Last year I'd filled with a mix of 91 and 100 octane, and had about 1/2 a tank left when it was parked the week before MSA last year. Wednesday of last week, to get access to my wife's 260Z (the Blue Turd) I had to move the thing. I was dreading the startup process after being idle for so long. I put a used redtop ultima battery on the fender, connected the terminals, and turned the key for the priming pulse, then cranked the car. Fired up immediately and went to fast idle. I moved off immediately, and drove the car about 1/8 mile from the back of the property to my new concrete 'project pad' up behind the house. The thing ran flawlessly, and really suprised me that the MS was running so well. I'd expected some stumbling, a pop or stall...but no such doing! Ran great, and hopefully, now that I'm laid off unexpectedly, I will have the time to finally COMPLETE this project. Picked up some Leather Supra Seats for it the day before I was notified of the termination, so they're bought and paid for. After almost 6 years, I may FINALLY complete the project started as a MS1 with 8X8 tables on the Magnus original MS-N-S code! Thanks to Z-ya for the diagnosis during the final portion of the CAS travails. I think at this point, given how superbly it started and ran I only have to concentrate on physical reassembly of the interior, and some 'sitting in the SoCalSun' cosmetic refurbishment. I hope to have it ready for some of the shows remaining this summer... Unless I get a J-O-B and have to tie up my time with more tedious things.

Ambient temperatures will not matter much, what is important is that if you have a choice, make the 'hot' pipe as long as possible, and the 'cold' pipe as short as possible. The decrease in temperature is what I would expect to see from this kind of rerouting of the pipes. A little thermal barrier wrapping may help on the front side of the pipe between radiator airflow and hot pipe from turbo...but putting it under the pan to get it to the other side like KTM did would probably work even better. Many people run them 'same side' and it's just not optimal for the space available in the car. I think KTM's setup which is close to the Option B setup is close to ideal, keeping the pipe away from the heat soak of air flowing across the radiator, and lengthening the time in the hot pipe before hitting the cooler core. Longer it's in the pipe, the more chance it has to give up it's heat. Hot pipe off the turbo will be hotter than most anything else in the engine bay short of the exhaust manifold, so routing it almost anyplace will allow it to cool. Cool pipe off the I/C will be cooler than most anything else in the engine bay, so routing it as short as possible will allow the minimum chance of soaking in any heat.

I'm with the rest, do NOT torque them to above what ARP says, and that means using THEIR specified lubricant. What you have detailed in effect is ARP's 'settling procedure'...torque, relax-settle, retorque, relax-settle, final torque. You are polishing the threads and making sure in those three steps that the torque you are reading is the actual torque of the fastener, and not some residual turning friction from the threads or the bolt head on the rod surface. They are multiple0use fasteners, but to make them last, they must be torqued to 75% of ultimate yield. If the fastener has any false torque resulting in a lower torque than specified, it will allow movement and tensile cycling of the fastener. This can result in fatigue breaks, or more likely fretting of the bolted parts. The procedure they are using is common in other applications where very precise torques are required due to specific yield points of the fasteners. You are basically 'bedding' the components, to allow for a more accurate torque when doing the final setup. The more they are worked as a matched set the more accurate a torque reading you will get on the fastener. That means mating the specific nut to the stud and keeping them mated for their lifetime. This will result in a more and more accurate torque for each subsequent reassembly of the component as turning friction will be further and further minimized. If you swap a nut...then the "three torques" procedure will mate them to a mimimaly acceptable state where they will return a proper torque / clamping load on the bolted component. You can see this in Impeller Nut Torques on Centrifugal Machinery. Due to balancing requirements they are match-marked, and if you torque to the same impeller nut after balancing, you almost always see the match mark misaligned. Try it with a simple stud and nut on a thick washer on the exhaust stud. Torque it to spec, make a mark, then relax it and torque it again. See where your match-marks on the nut ends up---chances are good each time you do this, the mark will go slightly further than the time before. This will reach a point where it stops moving for the most part. This is the same thing ARP is having you do.

Waitaminit! Are you telling me I MISSED OUT ON .50 Cent GOLDFISH WHEN I WAS IN TEXAS (Dallas/Austin/Houston) LAST WEEK?!?!??!?!?! MAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAN!

Beware of confusing the Roots type blower with the Lysholm Screw design of the WhippleCharger. The thermal advantages result in a much more efficient compressor. In industrial Applications, a Lysholm Screw in single-stage applications will easily run to a 4:1 Pressure Ratio and is more limited by auto-ignition point of nearby materials than the compressors' ability to compress air efficiently. I have seen lysholms pumping with discharge manifolds glowing dull red where operators lit their cigarettes off them! A Roots blower is limited in automative applications for the street to under 20 psi, usually. A Lysholm could easily run to 54psi, but at 20 psi the heat generated from a superior design and less internal recirculation will make much more power at the same boost level. They have normally six 'minipulses' per revolution, whereas the Twisted Lobe Roots would have at least three pulses where the pressure spikes and stabilizes... in either case, the superchargers are most efficient at 'optimal tip speed'---offhand I forget what it is, but overspeeding a Lysholm results in far less efficiency losses than underspeeding it. I would see if you can get an optimum tip speed number from technical support, and target your tip speed to be in that general area. Roots blowers just go to hell efficency-wise when under-speeded, resulting in a lot of HEAT. Same thing happens with their overspeed performance, because of the heat generated by the over-pressurizing pulse and the inherent blowback in their design. I digress...

Pressurise the float bowl, and raise your fuel pressure on a 1:1 ratio to your boost. At an idle fuel pressure of 4 psi, you will need 9 psi of fuel pressure to the carb at 5 psi of boost. It's either that, or you suck through the 750, into each of the twin turbos---which isn't hard to replumb either. V8 forum?

Hmmmmmmmm.... I wonder how that happened? (He rhetorically asked, knowingly...)

If you have a minimum of 150# of stuff to get coated, you can simply drop it off at the will call window at Sermatech Airfoil Management in Compton (Off the 91 and Wilmington) and pick it up later that same week... Prices are suprisingly inexpensive when you deal directly with the coater. They are an FAA certified repair station for internal jet engine components, so their 'high heat' coatings are not some B.S. marketing hype. Some of them are downright ugly, but will withstand over 2500 degrees F! Lots of the Cobra Guys take their sidepipes and headers there to be coated. Curiously, so do a lot of Top Fuel NHRA people...and some big name racing teams send their brake rotors there as well... Isn't it amazing how much useless trivia pollutes my brain? LOL

That is the standard for offset grinding. You weld up and offset grind. Works well. Kameari makes a forged 85mm crank...it's cost is a bit higher than what Paeco charges. Also keep in mind, if Paeco is standing behind their stuff like they were doing 20 years ago (they have been around for a while), Paecolloy journals are warrantied FOR LIFE against any damage. Hardfacing alloy used for VERY hard crankshafts for use in Racing Engines. If you ingest dirt or have a filter that bypasses and sends grit to the bearings, the hardfacing insures that the BEARINGS are the things that get eaten up, and not your expensive crankshaft. Submerged Arc Welding has been commonplace in the VW performance stroker realm for years. When you can make a 2.8 and 3.0 Liter four cylinder from an engine originally of 1500 CC's, it kind of tells you something! Big bores only get you so far!!!