240Z Turbo

Oh lord, another company with their heads up their ass! Well, of the 3 different torque specs ARP told me in 1 conversation, which one do you want to hear? I first asked what was the torque spec with moly lube and was told 60ft-lbs. I then said the last time I called I was told 48ft-lbs and the lady then said, oh yea that is what my catalog says! What the heck. I then proceeded to tell here that Tim's brochure said 35ft-lbs and she then tells me, go with that torque spec. What the hell! I said to her that she had given me 3 different specs within 1 conversation! She thought that was funny and began to laugh. I wish someone would develop a device to where I could shock someone through the phone. I would give her about 10,000 volts! I then ask to be transfered to someone who had a clue about torque specs. The next guy was sorta rude, I guess she gave him the skinny before talking with me. He tells me without a doubt that the spec is 48ft-lbs with moly and 61ft-lbs with oil. I asked him if he is sure and why that is different that what Tim's brochure stated. He said that I must be mistaken and that is what his book says. I did find that ARP only buys the studs and gets the spec's from the actual manufacturer. That is why the lady initially told me 60ft-lbs with moly because the manufacturer was telling them to go higher! What a crappy bunch of folks I spoke with. Can someone else call and let me know what they say? 800.826.3045

Man, the torque specs for the ARP head studs are as elusive and the Yetti! I called ARP and was told 48ft-lb with moly lube and 65ft-lbs with oil. I know of people saying to go 80-90ft-lbs, but there is no reason to do that and you weaken the studs. I also snapped a stud off in the block torqueing to 65-70ft-lbs with moly lube. Although ARP said it wasn't possible and I must have torque'd it much much more it snapped off. If you used moly lube then retorque to the specs ARP suggests. There torque numbers are based on the stud sizes from what I was told. I actually have to call them tomorrow because 1 of my studs is slightly bent and I will ask for the specific specs again. I won't be suprised if it has changed from what they last told me. BTW, Tim is correct about studs having a much higher clamping force with less torque. Hell, the pitch on the threads is different so stock torque specs immediately go out the window.

I want to help! I know for a fact that a stock t3 can generate 17psi of boost and have seen articles were they were run up in the 26psi range. I think most any turbo can produce alot of boost, but whether it can use it or it has any effeciecy at that level is a different story. When you have problems with boost dropping back off that is usually caused by excessive back pressure. A few years back when I ran the stock downpipe, 2.5" exhaust and chambered muffler I had the same pressure. The exhaust could not physically flow enough and then because the exhaust backpressure built up it caused the boost to lower. The 1st thing I did was remove the chambered muffler and the problem was immediately solved. If you can measure the backpressure that would give you the answer to what I am proposing.

Is this true? Can you not take and RB26 motor and use the RB30 crank to stroke it? I understand that you will need to change rods/pistons? Thanks for the info. I will be a future skyline powered Z(AWD)!

I am just waiting for my damn head to get this thing together again. It is supposed to be shipped out tomorrow, but I will believe it when I see it. The oval exhaust measures 2-9/16"x4" on the OD. It has an area equivalence to a 3.5" round, hence called the 3.5" oval. I can't wait!

That does not sound correct. There is no reason your motor cannot run smoothly with the Electromotive. I have been running the Tech for about 4 years and never have had a problem of losing part of the map. That does not sound possible. Things that do happen are people not properly grounding the tech chasis and the coils spark over and cause the tech to cut off or momentarily stumble. I think the problems you hear of are from people who do not know how to program a fuel system period. You don't so much need an understanding of the Tech software as you do the basic principles of fuel and timing. Hell, having never used the Haltech I spent 1night looking over the software and then tuned my buddies Honda Racecar and made 554hp@wheels and the car went 10.31@142. If someone knows how to tune the Tech your car will run like a champ and have no problems. It is true that you can constantly try to dial in the car for every last hp, but once the tuning is done, you need not jack with it again. Here is another story. I tuned a GN powered Malibu for a friend running the Tech. When he ran the stock GN computer the car went 12.25@116 with about 23psi of boost. After installing the tech and me spending only a few hours of total tuning on the car it went 12.35@111 with only 13psi of boost. Anyway, I know TimZ will jump in and give his inputs as well. I will admit that the tech software is not the most user friendly, but if you know how to tune your car should run fine. BTW, the Tech III will not be out for atleast 6 more months.

John, my initial leak down tests after about 3 months were all less than 1% using XC rings and 4 of 6 were about 1/2%. I more recently did a leakdown of the motor with over 1year of hard boosting and had less than 1.5% on the cylinders I tested. I think having an understanding of the importance of the finish hone on the cylinders will ensure that the motor correctly seats and has very little leaddown. Anyway, thanks for the response and let us know the progress of the motor.

Yes, Electromotive liscensed that stuff to those guys.

John, I spoke with Jim today as he is doing some mods to my turbo head. He also built my 3.06L turbo motor. I have been in the shop and it is very clean and organized. Expect to wait a bit, but you should be happy with the results. Let us know the specs of the new motor and why did you decide to go with Sunbelt?

Ron, people are and have made 500hp with the stock exhaust manifold. However, I would do as much porting as you possible can to help flow. The inlets can be heavily ported, but the best area to hit is where cylinders 1-4 enter through 1 opening to the turbo area. If you stick your finger in there you will notice the top wall can have atleast 3/4" of material removed. Anyway, I don't think you will have a problem using it for your application. Hell, TimZ made 391hp&410ft-lbs @wheels with that manifold. However, a tubular exhaust manifold would probably net about 40hp on a big turbo application.

Ouch, that is a bit expensive for those units. My buddy was at a boat race in Michigan, so I will have to get you the pricing info tomorrow. You can get those for cheaper than that. As far as the rod, I know Scottie use to run 17psi with the same method of placing more tension on the rod.

Daw, food for thought. It is nice to have a higher stall converter in a turbo car if you are running a monster turbo. I ran a 2900stall with my T64 turbo and a built 4N71B and I thought the stall was too low. My new stall was built by protorque and it is a whopping 5700rpm. I know this is too high, but I am waiting to finish my new twin turbo setup to have it lowered to about 4000-4500rpm. The stall will not actually rise above 3200rpm unless you throttle and start building boost. It does not drive around slipping like hell and makes for an awesome ride. Anyway, if you need any info on the 4N71B buildup just let me know, it is very cheap and easy and will survive 500hp in a 240z with no problem.

I don't think at this point I will coat the manifold in case it cracks for some strange reason. I am going to have the intake 1300F coated in flat black by Jethot for about $130. The turbo's are 2x Mitsubishi TDO5 16G turbo's. The compressor wheels in those things are identical to the stock t3 compressor, but the TDO5 housing flow better then the garret housing from what I have heard and it is packaged much tighter. They are rated at 1010cfm@15psi. It should be interesting when all is said and done!

I have to deck the flange and port on the inside to remove all the sugar and excess crap, but that is it! 240Z Turbo TT header pics

Evan, just drive the car normal and try to constantly vary the load within the 1st few hundred miles. Don't do a long constant highway drive as that is said to be bad for seating the rings. Most likely the rings will seat instantly. As far as boost goes, set it to its lowest point, 6-9psi. It is ok to see boost, but do not take the motor over about 5K and try to keep the boost low if possible. Remember, you don't buy a factory turbo car from the dealer and not boost on it when you are taking your test drive. Just be nice to it for about 500miles and then it is yours to jam on.

The flange is 5/8" from Clifford Performance for $49 and seems to be hot rolled steel. The tubing is .065" 304 Stainless and the turbo flange is 1/2" cold roll steel. I used 309 rod to weld the SS to steel and either 308 or 316 rod for SS to SS. I called several header companies that make good turbo headers and they all said not to use SS for the Header flange because it is too brittle. Alot of turbo headers use mild steel flanges and SS pipe. Trust me, I would not have done it if I didn't know and had not researched it. As far as the welds, they are all heli-ark's(spelling). I put a nice bevel on all the edges and then grinded them and whiped them with Acetone. Not too difficult, but time consuming. I just finished the rear and will post pics of it on my car with the rear turbo.

Flow difference is roughly this: Auto-13.8 GPH Manual-9.6 GPH I don't remember the specific #'s, but this is roughly the flow difference between the 2.

Flow difference is roughly this: Auto-13.8 GPH Manual-9.6 GPH I don't remember the specific #'s, but this is roughly the flow difference between the 2.

I thought about making a custom intake and then realized I had already made one! Anyway, the back of the turbine housings have 2 holes, wastegate and exhaust. I am going to run both wastegate tubes from the turbo's into 1 single tube that meets at the Racegate Wastegate. This will also serve as a balance tube between the turbo's. Once the charge leaves the turbo's I will immediately join them into 1 single 2.5" tube to the intercooler and from the intercooler a single 3" tube to the TB. Here is a pic of how I will merge my 2 turbo's into 1 single 2.5" pipe. Of course mine is not a skyline, but the concept is just the same!

Did you say kit? CHUCKLE! Actually, I am sending this header to my buddy Marcus and he is going to make a jig for the header in case someone wants one. I will not do downpipes at this point and it would be header alone. So to answer the question, yes this header will be available for purchase in the near future.

Well, finished the rear turbo header today and did a fit up in the car. I am pissed because I accidently put a slight angle on the turbo which makes the front of the turbo angle down. No big deal, but I wanted it level. I guess i'm not much of an engineer! Anyway, alot more room than I though with it all done and with the motor scoot back 1" it clears the steering rod by a mile. I bet making the downpipes and doing the external wastegate tube will be just as exciting.

No, even with my motor set back about 1" it still clears the stearing shaft by about 1". I will take a pic tomorrow with the rear turbo bolted on so you can see the setup and clearances. BTW, I'm getting excited!

Well, I have done the rough fitment and weld of the rear turbo setup. I should have it completed tomorrow by midday. I will have the front finished by next Tuesday. Anyway, not the most fun thing I have done, but a learning experience for the front turbo. You will notice that I used a boring bar to bore out 1.75" diameter x .170" depth into each port so that the SS tube would fit into the header flange and give a more secure fit for welding. Anyway, almost 1/2 way there and will post the pics of the finished rear stuff tomorrow.

Evan, send me your mailing address as I think I have something for you.

Damn, 12psi of boost! DOH! I knew there was a reason I wanted to do the AWD skyline setup in a 240Z. You definitely show the potential of the motors and yours is not a super built motor is it? Man, the proper setup could easily create a 9 second street car! Anyway, that is awesome what you have done and I wish I could get my car to the track this century. The new twin turbo setup will be complete within a months time. BTW, what kind of tires are you running?