Question on my turbo setup

[260turbo]

yo, i am brand new to this site and i have a question for any of you turbo buffs. I am setting up a 260z with a 82 turbo motor pushing a t4. I am wondering if anyone around here has done this before? and if any one can give me an estimated hp, 1/4mile, etc.? I have a built bottom end, 75 intake with m'benz injectors on a custom rail(i was told they are somewhere around 450), 240sx throttle body, garrett t04b with an a/r1.00 on the exhaust and an a/r .63 on the compresser, external wastegate set currently at 8psi, intercooler, hks bov, 12:1 rising rate fuel pressure regulator, vortech t-rex fuel pump 50/70 and 5 speed tranny. So anybody have any ideas?? I have been told that it should be a cobra killer and quite possibly a viper killer. But I would like some second opinions. Thanks for your help! Austin

[Forrest]

There are hundreds of posts about many many topics related to your project. Welcome to the board, try the search function or just browse the turbo forum.

 

One thing I would suggest is getting a standalone efi, otherwise you're going to hit some limits pretty soon.

 

-Forrest

[Doug71zt]

Welcome Austin - You might want to rethink the exhaust side of your turbo. A full T4 with 1.0 A/R is going to be a laggy beast on the 2.8l. What trim is your exhaust wheel? I think that the most popular T4 hot end used here is a P-trim wheel with .70 - .80 A/R. Usually with a 60-1 compressor. HP and 1/4 mile times are wildly varied - depends on the overall balance of the engine systems and tuning. My current 2.8 runs 12.2 @ 116 with slicks, 12.7 off the street at 15psi.

What EFI/timing control are you going to run? You are going to need some way of retarding the timing under boost. 12:1 rise rate on the RRFPR sounds a little high - 30 psi base will get you 126 psi fuel pressure at 8 psi boost. I think that's not going to work very well. If you are going the budget route, I would run the Z31 efi system and maybe talk to JWT or Bernard about a custom chip.

I don't think that you will even have to search this forum, just read back through the old posts, it's all good relevant information.

 

Good Luck - Doug

[260turbo]

hmmm... well i aquired the engine and what not from a guy around here who was building it. Also my t04b is an a/r .60 47mm s trim compresser with a p trim exhaust wheel. I am aware of the lag on that 1.00 but i have heard that when it boosts it with boost higher and stronger(true or false). Well since i have some things wrong, what all would y'all say i should change? I need some ideas on timing control(retard and whatnot). any help would be great!!! I am on quite a budget but yes i do have the stock computer. Anybody who knows a really good Z wiz in the Mississippi(preferably)/AL/TN/LA area that would be open to helping a novice out would be awesome. BTW i am a 17 y/o Zer who is still learning the ropes. My goal is to embarass my friends heavily modded 96 cobra. Don't think it's hard just have to figure out how.

 

Thx austin

austinc7@juno.com

[datsunan]

Don't think thats going to be easy. I have raced a stock cobra in the 1/8th and lost, not by much but it was still a lose. True it was the first time racing my car I still don't know if I could take him today especially if it were really modified. Your going to need some serious traction to even have a chance, traction in the Z can be expensive. Try to find a 88-89 z31 turbo they had posi rear-ends. As far as fuel managment I'm running the Jim Wolf Technologies ecu which is a Z31 modified and this system is capable of 400hp on race fuel and 350 on pump, it still uses the stock fpr. You want about 35psi at idle and 1 psi for every pound of boost or your going to run rich with those large injectors. You've got alot to deal with, hope your up for it but this site is a great resorce just make sure you search bofor asking something that has been answered a 100 times. Good luck.

[Clifton]

[quote name="260turbo Also my t04b is an a/r .60 47mm s trim compresser with a p trim exhaust wheel. I am aware of the lag on that 1.00 but i have heard that when it boosts it with boost higher and stronger(true or false). Well since i have some things wrong' date=' what all would y'all say i should change?Thx austin

austinc7@juno.com

 

You aren't going to kill any Vipers with an S trim T4, way to small for serious power. Yes the 1.00 a/r would be ok and make more top end, if you could make power till 8500 rpm. You will hate driving the car with that large of an a/r. I would sell the turbo and get something better suited to your needs. Even the "T70" on Ebay would be 100% better than what you are going to use. They are Ptrim 60.5 mm compressor and T3 flange too.

 

I have the MSD boost retard (not the 6A model) on my turboed Toyota truck, along with 2 450cc additional injectors for extra fuel. 17 psi on 91 octane, couldn't do it with out the MSD pulling some timing.

[Guest bastaad525]

I agree... that rising rate regulator most likely going to have you running real rich on the boost. Most of the guy's who really know their stuff around here recommend against using a rising rate AT ALL, because they are difficult to tune to give good air/fuel ratios in ALL conditions.

 

After much inquiring myself, I have to agree, rising rate regulators are NOT ideal for our cars. Rather, rising rate regulators are for guys who are putting a turbo on a car/motor that didn't have any kind of forced induction in stock form, and therefore their fuel systems have no way of dealing with boost... in that situation it helps to provide that extra fuel whenever boost is present. But in our cars the ECU is already 'trained' to deal with boost, though admittedly, not 8psi of T4 boost With the bigger injectors, you shouldn't really need an RRFPR at all... then again that depends how big the injectors are. Lots of guys run lots of boost with bigger injectors, with stock fuel pressure, and just tuning the air flow meter to compensate for low/midrange richness. Lot's more still run the bigger injectors with just a regular/non rising rate, adjustable FPR so they can fine tune their overall fuel mixtures w/o messing with the air flow meter.

 

Stock Z turbo EFI runs real rich on it's own in the midrange, it just starts to lean out at higher rpms... this is all you have to compensate for. Bigger injectors can handle that by themselves no problem... I say ditch the RRFPR. If you say your injectors are 450cc's, I am pretty sure that is more than enough for 8psi of T4 boost.