GrayZee

Yeah, after I went for a spin with a z31 ecu, the thought of putting back the original ecu seemed like the dumbest move you could ever make.. The throttle response and driveability is WAYYY better. MAF>AFM, (maf+z31ecu)= Of course after 4 years I am going to a z32ecu/maf/cop/cas upgrade...

Yeah, I would not suggest cranking it all the way to 35... drive it for a while like that. However, if you like power... bump it up to 26 after a bit and see how that feels..

The base timing at idle is 20 degrees, it is a good idea to unplug your TPS and cross the two wires with a small wire or paperclip or something. This will put the ECU into "limp" mode and will not try to make any timing corrections. Altough the base timing is 20 degrees I would not be afraid to advance if you have a stock chip, I kept advancing mine by 2 degrees at a time and felt more and more power every time... I ended up running it with the timing mark on the T-cover right over and past the scale on the pulley. It ran great with no ill effects.

It will bolt up to your transmision just fine, however I do remember that the turbo z31 has the left front engine mounted further forward on the engine. (perhaps the crossmember is different as well then?) Also I think the alternator might be in a different spot... I'm going back about 4 years on my memory though...

You can make calculations all day but in the end I don't think the differences are going to matter that much at all. I usually go by the simplest route, transition the pipes to match the outlet of the turbo and the size of the throttlebody. If your turbo has a 2" inch outlet and your IC has 2.5" in and outlets and you have a 2.75" TB... then just start with 2" and in logical places (I like to buy silicon reducer hose) and work your way up to 2.5 at the IC and up to 2.75 after the IC or near the TB.

Hey there, where abouts in the Great White North are you eh? Although I don't have direct experience in your exact swap I do know a bit about Vg30's and their electronics. I would have to say that you need turbo manifolds (or possibly just the left side) The turbocharger of course, turbo oil pan (or modify yours) oil line and fittings, some plumbing for the air intake and the pressure pipe (or custom intercooler) and exhaust. You will also need a turbo ecu. I have one if you are interested. There should be no wiring mods needed.

Unless you are gonna use some sort of "tunable" computer, don't even bother upgrading injectors. The stockers are 260cc and should be able to take you very near the limits of the stock T3 turbocharger.

Thanks for the info guys, I think I'll be ordering a OBX!

1. There is a Nissan/Infiniti M30 ecu on ebay right now for $89 buy it now, including shipping. 2. M30 ecu's use sequential injection. 3. It is very tunable. 4. It has the OEM look (although more modern style than anything a L28 would have had) 5. Gas mileage is based on AFR's and O2 feedback, which can also be tuned in with the M30 6. Best of all, it uses the stock L28et/Vg30 crank sensor as long as a Vg30 disk is installed.

I have been following this thread. It seems there are some issues with the OBX to be sorted out. I am curious though, would you guys still recommend the OBX or not?

Yes, but you have to make a few mods to the harness. Like the maf sensor plug and ecu plug have to be changed. There are also some changes needed in the fuel pump circuit. Of course you need a Vg30 type CAS wheel. I have a M30 ecu that has already had a eprom socket installed if you are interested.

The cyl head temp or (CHTS) has two wires, one goes to the ecu, the other ties in with a wire from the AFM and then also goes to the ecu. The efi relay turns on the main power for the CAS and the AFM as well as runs a signal back to the ecu. Which is funny because the efi relay gets a signal from the ecu to energize. It is like the ecu has two wake up modes... partially awake, and fully awake.

I think I really lucked out mounting my afm when I first did my turbo swap. I found a plastic air intake pipe from a early z31 N/a It was the perfect fit to go in the stock rubber boot off the turbo and it went through the rad support and bent 90 degrees after. It had a 3" rubber end that the afm fit right into. Perfect fit cold air intake, it's almost like Nissan planned it.. LOL I think I still have it if you are interested, I also have a Jpipe that has been modded to accept a 2.75" rubber and connect to the 60mm throttle body.

Now that makes sense.. maybe all we will end up needing is crazy catch cans for our Z's I know the Honda guys often weld extra nipples to their valve covers and run extra hoses for their catch cans.

I bet you can find a diagram at autozone.com Just click on the repair section and enter the vehicle specs.

I have been thinking about the idea of gasoline engines running hotter than diesels and therefore shortening the life of the turbo, although it sounds plausible at first I don't agree with it. How many turbochargers are there out there that are specifically designed for use with gasoline engines? Percentage wise the numbers are very small. Without question diesel engines are the king of turbo applications, mostly medium to heavy duty trucks. Futhermore how many gasoline engines are there out there with turbochargers that are capable of much more than 250hp? There is alot of engineering that goes into designing a turbocharger, I doubt very much that alot of turbos have been made with the car modification scene in mind. The market is way to small to justify it. Take a GT35r for example, I do not know the exact model but I have heard that you can find that turbo on a european market medium duty Volvo truck. I would bet that any 300+hp turbo you can buy from a Garrett dealer has had it's roots in some sort of diesel application.

I have only had my Holset running on my Z for a very short time and it has been parked all winter. So far I love the turbo, great setup for a L28! I am not saying that in the future I may feel not feel differently about Holsets but I hope not. I would be interested to hear any other bad experiences people have had with them. One thing I do know from my personal experience is that people make far too big of a deal about shaftplay. To some extent I think it is normal after some use. I have used turbos that have been deemed "worn out and no good" turned around and used them anyway with great success. One guy gave me his turbo because his mechanic told him his turbo was toast, and I ended up using it for two years with no issues. Another turbo I used for a short time was one that I had been given a upgraded compressor wheel and housing for stock L28 turbo. The wheel had touched the housing and burred the tips of the wheel and scratched the housing. A guy that had worked at a turbo shop said the turbo was un-salvagable. Well being the cheap bastard that I am, I decided to clean it up a bit with a dremel. The guy from the turbo shop was at the track that day when I ran a 13.4@103mph with it. He could not believe it. Before the upgrade the best that I had done was 14.5

Ha ha ha... that is funny... very true as well.

dude, I understand that... but they have vbands in MANY sizes...

I know the answer but I don't have the info I need in front of me. This much I can tell you right now... Red= 12vdc switched ignition (Efi relay) Black= ground Green and white are output signals (one puts out a faint pulse 360 times per revolution and the other puts out a stronger pulse ONCE every revolution) sorry I don't remember which is which at the moment but I have crossed the green and white before and it didn't hurt anything. If you can get your hands on a Vg30 engine and have a look at their wires I know they are all the same as a L28et. (300zx/Maxima/Pathfinder/truck)

I was looking for a vband to fit my exhaust DP, I paid over $100 from the Dodge dealer for one and then a friend told me about a local store that sold air filters and such for heavy trucks that might have something like that.. I ended up driving down there and the guy took one look at my Hy35 and knew exactly what I wanted (including the part #) It was $20! Seeing I never even used the Dodge one yet I returned it and got my $100 bucks back. Perhaps you can find a local business that help you? The store in my city is Ideal filter and supply in case you are interested. (204) 697-4332

Does your wastegate dump to open atmosphere? If so, can you hear it opening?

If you really don't want a intercooler I am sure you can get away with spraying water/meth instead. I used to run up to 18psi on a stock L28 turbocharger using a very budget windshield washer injection system.

http://www.mcmaster.com/

I have a godspeed intercooler. No complaints at all about it. I can't tell you any specs about pressure drop, but I did run 19psi On my L28et/holset Hy35 with no signs of detonation. The dimensions of mine were different however, I believe they were about 27" x 6.5" x3.5" with 3" inlet/outlets on the same side. The 27" was too wide for my 280z, so I cut it down to about 23 or 24" and welded aluminum cap plates over to seal it back up.