240Z Turbo

Jeff, that is 600hp @wheels to get the 10.07 right? BTW, there is no way the 4N71B would run deep into the 10's. However, I bet an 1800lb Z car can use the 3N71B and run into the high 9's. Picked up my 200-4R shell today to mockup in the trans tunnel for clearance issues. I also realize the necessity of getting a stronger trans.

I think you hit on most of the points. The reason for the swap is the Jatco is not the best for racing with 500+hp. I recently ran 2 11.1 passes and 2nd gear crapped on me. I pulled the tranny to find I bent the tab on the 2nd gear band and it had alot of heat wear(fadded black). I stuck in the new Kevlar lined band so it should hold for a while longer. I also want the transbrake and the ability to lock the converter which this tranny does not have. I have the non-electronic unit so it only locks the converter in OD. The 200-4R is a smaller unit than the Jatco, but most closely resembles it in gearing and that it has OD. Parts are fairly cheap and it can be built to survive the hp without breaking the bank. The C4 is so much smaller than any other Auto I have seen and the parts are much cheaper than the 200-4r and it will hold the power with no problem. However, the mounting approach is much different than doing the buick/olds. I like the idea of the adapter so folks can run the 200-4R, Turbo 350, powerglide, etc. However, I should consider what I need over what I think others will want. My tranny is our right now and I will pick up the 200-4R shell from my buddy and mock it in the car for clearance issues. After that, I will need to make a decision as to which tranny I want to run.

I am looking serious into my next project which is an american auto trans swap into the early Z. I have narrowed it down to either the 200-4R as in the Buick GN or a C4. Both have advantages over the other. I plan to fab an adapter plate to mate the 200-4r to the Z and in the case of the C4 I will machine the 3N71B or 4N71B bell housing to bolt up to the C4 tranny. My specific question is this. On the 3N71B or 4N71B detachable bell housing, what is the diameter of the hole in the center that goes about the pump and what is the bolt pattern of the pump. Both can be approximates with a ruler and no exact measurement is necessary. Your help is greatly appreciated.

I run a web cam grind 155. I had them push the lobe centers to 110.5deg. I will probably upgrade to grind 87 in the next 6 months. http://www.webcamshafts.com/datsun-auto.html#1

bigger is always better in my opinion. Tial is very nice and the 40mm should be good. I believe they are rated for 500hp. The racegate is 42mm and it is rated for 800hp(????). Anyway, I run 2x HKS 40mm standard wastegates. The kicker about both are the hole is actually 35mm for the HKS and Tial 40mm. It is only the OD of the valve that is actually 40mm. Who'da thunk it.

I am sure there will be more supply than demand on these manifolds. No money necessary until the manifold is complete and I post a pic of it. You can see what you get before you get it. Even my current manifold does not have equal length runners as seen below with 1&6 being the shortest. It may/maynot be that critical as the car seems to make good power and there are no noticable differences in the spark plug color from one plug to the next. The idea is only to create a manifold with larger runners, 1.375" ID and a larger plenum. I can get fancy and add 6x full radius velocity stacks, but that will add $250 to your bill. I have to buy the mandrel bent aluminum tubing and 6x velocity stacks. I don't know how critical aiming the TB toward the #3 port is, but I would think if the plenum volume is large enough then it starts to become less of an issue. I will put a slight angle on the TB as I did on my 1st intake. Here is a pic. Anyway, I expect to have a few pumped out week after next.

Well, the SR20DET has similar port and combustion chamber design to the RB26. I believe the heads flow in the 250cfm range stock. On my buddies SR20DET'd RX7 he made 396hp@wheels w/out the nitrous with only HKS cams and this was on pump gas. Not to mention it is a 2liter 4cylinder motor. I think if someone wants bang for the buck swap a silvia motor into the 240Z. Much lighter and much cheaper to make good power.

Well, his car ran crap for 1/4 mile times, but yet claimed 400+hp@wheels. It didn't jive then and it don't jive now. He won't post because everytime he made some claim I called him on it and he got pissy like a school girl and ran home to mommy. I won't say whether it is larger or not, I don't know. I do know this, I am building about 9 intake manifolds and will be selling them for $600. They will be the 280zx manifolds cut 1.5" off the flange and decked in the mill. The ports will be bored on a mill to 1.375" to match the gasket. We will then weld 1.375"ID tubing to the flange and on the other end the plenum. If you use other than the stock nissan TB boltpattern you can send me your TB and I will make the TB flange as necessary. Anyway, John Talyor is supplying me with the manifolds and he will get the 1st one. It will look like the manifold below, but with a square plenum. Same method of cutting the flange as I did on my setup. Using the 16G tubing on the runner makes this intake very light.

my buddy used to tell me, "if you go to the junkyard....you get junk!" I never understood that comment

Head design my friend. How do you make power? You MUST be able to flow air into and out of the motor. My head flows in the 200cfm range tops, intake ports. Not bad for the head, but when honda guys are getting 300cfm from the intake ports you can see how they make so much power. Also, combustion chamber design plays a significant roll. Another thing is 1 large valve vs 2 smaller valves has said to lessen reversion. Bottom line, the heads don't flow high cfm in stock or lightly modified form. I did find a guy that says he can make the head flow 290cfm by raising the ports very high and making them in the 1.75" ID range. One note, a friend of mine has a turbo mustang running 5.1@146 in the 1/8th. The heads flow 400CFM. Does that tell you anything?

Hey, that info was from Corky Bell and I don't know if it actually holds true. If you look at his cores and flow #'s.....well....I said supposedly!

I have one installed on my TT240Z. If all else fails...read the directions! Boost signal to box...box to wastegate....tee off fuel pressure regulator line and run to head unit with filter inline....power....ground....miller time! If you have specific questions when you begin just ask. It is really straight forward if you read.

Joel, those are 2x Walbro GSL 392 pumps(255 l/h). I ran 130mph with just one hooked up. I will run the 2nd pump on the new setup with 23psi and 100shot. YOWSA! The 11.2@129.5 was 16psi and 100shot. Toluene seemed to work well although I was not as aggressive as you. I ran 22psi and 20deg or so, not 23psi and 24deg as you do. Maybe next time.

The blue hose was from Turbonetics, but our good friend Hoover sells them at Turbohoses.com or you can try bakerprecision.com and it is much cheaper. The SS t-bolt clamps are about $4 from my local industrial hose supplier. Please realize most of these shops like Turbonetics DO NOT make 90% of what they sell and charge out the ass for it in markup. Those same clamps are $10 most other places. If you are interested Hoover also sells them.

from each turbo the pipe size is 1.75" and they merge to a single 2.5" to the IC. From the IC to TB it is 3" piping. For the VLSD stuff, yes you can use RossC's adapters. I just made a set of Axles for JoelS and he also uses RossC's adapters. Search under Drivetrain for the details. If you can get me the VLSD input shafts and the 280zxt outers I can have them built with new stuff for $200+shipping. So far ZGad, JoelS and myself are successfully using them. I have had them in my car for several years with NO problems.

tuning is going well, got the AFR's in the 11.3:1 range thus far with about 21deg timing at 18psi. Ran 1gal of Toluene this week and upped the boost to 22psi. Runs like a SOB, but the auto tranny is deceiving as it does not whip you around like the 5-speed does. The nitto drags do not spin on the street at all(no nitrous) so it just goes. I will try to make it to the 1/8th mile within the next 2 weeks. I hope to see 105-107mph and high 6's in the 1/8th. My other setup bested 102.7mph in the 1/8th.

well, I was running 230kpa(about 18psi) on the twinturbo setup with the monster twin-core Garrett intercooler. I will try to take a screen shot later today of my current timing curve which is more conservative and should work well for most turbo setups. I am running about 8.7:1 compression currently. You can see timing ramps out very fast from 97kpa to 120kpa(0psi). You will want to ramp the timing out quick and then taper it off. It does not have to follow exactly as mine, but gives you some ideas. you will need to find the magic point between timing and fuel and which combination to eliminate detonation coming onto boost. Less timing and less fuel or more timing and more fuel?????? Good thing I have an automatic car, I sort of breeze by that part of the map fairly quick.

More timing than you should be running, but this is an old map of mine.

supposedly, the flow is increased 4x. flow in this case is related to drag so flow is proportional to the area^2. anyway, increase the area by two and you increase the flow 2^2=4. Never flowed one myself to see if this holds true.

8.7:1 and 18psi on 93 octane. Power is in the 500hp@crank according to injector duty cycle.

We all know Scotties car has run much faster, but it was the race that counted! I actually won twice...once because he red-lighted and again because I ran 11.265 to his 11.289. I have to be fair and mention he has run 10.31@131. DOH!

The video is on my site. I have started to get it updated again. BTW, although he hit the lights 1st he redlighted on that run. My 11.265 to his 11.289. http://www.eng.fsu.edu/~jthagard

No new vids right now, but I could make one. Did some full boost tuning with the wideband today, but had problems with dropping fuel pressure under boost. The prefilters where partially clogged and after cleaning them I jacked the boost to 18psi. I will dial it in tomorrow with the wideband and be done with it for a while. I can take some vids next week and post them if you like. Perhaps a vid from a buddies car of my car getting on it?