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On 7/24/2022 at 9:34 AM, joshuaho96 said:

Running rich tends to cause the cat to overheat.

Not in any meaningful way. Face it, cruising "rich" puts far less heat into the cat than running it under high load rich - and they always run very rich under high load.

There are so many better solutions here. All of them starting with installing something useful. A wideband, for one. An aftermarket ECU, for another. I just wish we weren't facing another generation of broke arse people buying GTRs without the f**king financial wherewithal to do what needs to be done and instead trying to drag them around on the bones of their arse, just because they spent their last $75k on a 30 year old Datsun.

  • Like 1
On 7/23/2022 at 6:15 PM, GTSBoy said:

Not in any meaningful way. Face it, cruising "rich" puts far less heat into the cat than running it under high load rich - and they always run very rich under high load.

There are so many better solutions here. All of them starting with installing something useful. A wideband, for one. An aftermarket ECU, for another. I just wish we weren't facing another generation of broke arse people buying GTRs without the f**king financial wherewithal to do what needs to be done and instead trying to drag them around on the bones of their arse, just because they spent their last $75k on a 30 year old Datsun.

I don't disagree, my dad's Camry survived years with a bad O2 sensor but I still don't recommend running it that way. I do agree these cars are insanely expensive to fix up after decades of deferred maintenance and anyone not prepared for that should really look into getting something else.

On 23/07/2022 at 9:07 PM, TXSquirrel said:

There are 2 different GT2860R, do you know which one you have?  Or a part number?

Garrett 836026-5005S, GT2860R Turbo rated for 250-360hk i belive it is. I will double check.

 

Thanks😃

On 24/07/2022 at 3:15 AM, GTSBoy said:

Not in any meaningful way. Face it, cruising "rich" puts far less heat into the cat than running it under high load rich - and they always run very rich under high load.

There are so many better solutions here. All of them starting with installing something useful. A wideband, for one. An aftermarket ECU, for another. I just wish we weren't facing another generation of broke arse people buying GTRs without the f**king financial wherewithal to do what needs to be done and instead trying to drag them around on the bones of their arse, just because they spent their last $75k on a 30 year old Datsun.

Thank you. 

I bought thus GTR just because i wanted to do a full maintenance on it. The engine is new built first of all.

But i also have an s15 which i have done a fully built sr20, whole chassie/every single bolt and part except inner roof has been removed. Im soon done with my s15 and trying to keep the GTR as stock as possible and make it like new again. Thats why i wanted a stock ecu. My s15 is everything but stock haha

On 14/07/2022 at 11:27 PM, Duncan said:

I've never heard of any differences in the car side wiring between all 32 GTRs, so any ECU will fit and work.

It would help to post full part numbers if you want input, rather than people having to guess/research if they want to help

Garrett 836026-5005S, GT2860R Turbo. Rated for 250-360hk, but i will double check this.

aftermarket ecu will be the way to go anyway, it feels like there is to many gray zones here 

So you bought -5 turbos, no grey zone about it. Pretty far from standard size turbos, as now at a minimum you'll need bigger fuel pump, bigger injectors and completely retune the car obviously with a non standard ECU.

Unfortunately the seller has given you bad advice about those turbos. They are a direct physical fit (potential oil drain and oil lines issues but everything else should be OK), but they are a lot larger than standard.

In addition to what BK said you also need either nismo or z32 air flow meters if the new ECU doesn't run MAP sensor. Those turbos flow enough that even at factory boost you will fall off the standard maps.

On 25/07/2022 at 11:26 AM, BK said:

And -5's are pretty laggy on the street with a 2.6 which is why -7 and -9 exist.

God damn are they fun when they do kick in though!!  Mine had -5's when I first got it and when it hits boost (probably at around 4500-500 rpm the thing felt like it was in Startrek!  Fast as hell yet slow as hell until you got there....

On 25/07/2022 at 1:12 PM, Shoota_77 said:

God damn are they fun when they do kick in though!!  Mine had -5's when I first got it and when it hits boost (probably at around 4500-500 rpm the thing felt like it was in Startrek!  Fast as hell yet slow as hell until you got there....

Yeah on the strip they're OK, you can squeeze a 10 out of them on pump fuel.

On 7/25/2022 at 1:56 AM, BK said:

So you bought -5 turbos, no grey zone about it. Pretty far from standard size turbos, as now at a minimum you'll need bigger fuel pump, bigger injectors and completely retune the car obviously with a 

Yeah, i confirmed its -5. So running standard boost and standard power with stock injectors and pump on these wont be an option? F##k me

I have the 2 old one still here. 2 hks turbos i belive are gt25, cant find anything about them and the identification label are hard to read. Maybe sell the -5 new turbos and send these ones in for rebuild and fit them instead?

20220723_105805.jpg

20220723_105812.jpg

Edited by timmy94
On 25/07/2022 at 2:09 AM, Duncan said:

Unfortunately the seller has given you bad advice about those turbos. They are a direct physical fit (potential oil drain and oil lines issues but everything else should be OK), but they are a lot larger than standard.

In addition to what BK said you also need either nismo or z32 air flow meters if the new ECU doesn't run MAP sensor. Those turbos flow enough that even at factory boost you will fall off the standard maps.

So i guess i have to ask now. What do you recommend? Sell these turbos and put the old ones gt25 back? Since i dont have an ecu now and i will send the r33 ecu back i guess i will get an older version of LINK G4 or something

Interesting they were not stock turbos in the first place. I guess you may not know much about the history of the car but it is possible the tune on the old ECU was not factory.

The tags read

UH 60539

431876 45

but unfortunately I have no idea what that means.

Had the old turbos failed or were you just replacing them? If they failed, rebuilding them turbos with steel wheels would get you going again. The -5 you bought are about the biggest turbos you would consider outside drag racing etc but are not impossible for street use.  If you go -5 you might as well buy a tunable ECU (and fuel pump, injectors and either MAP sensor or z32 air flow meters) because they will never run well on the factory computer, even with very low boost (they are larger, so they move more air than the standard ones at the same boost level).

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Dose Pipe advice:

  • Throw stock ECU into bin
  • Throw stock AFMs into bin
  • Throw stock O2s into bin
  • Throw twin turbos into the bin (optional)
  • Buy Haltech Elite ECU
  • Buy Haltech Motorsport MAP sensor
  • Buy Haltech canbus wideband
  • Buy twin scroll modern single turbo, and twin scroll manifold (optional)
  • Install Haltech, wideband closed loop O2 correction, enjoy car.
  • Like 1
On 7/26/2022 at 8:17 AM, Duncan said:

Interesting they were not stock turbos in the first place. I guess you may not know much about the history of the car but it is possible the tune on the old ECU was not factory.

The tags read

UH 60539

431876 45

but unfortunately I have no idea what that means.

Had the old turbos failed or were you just replacing them? If they failed, rebuilding them turbos with steel wheels would get you going again. The -5 you bought are about the biggest turbos you would consider outside drag racing etc but are not impossible for street use.  If you go -5 you might as well buy a tunable ECU (and fuel pump, injectors and either MAP sensor or z32 air flow meters) because they will never run well on the factory computer, even with very low boost (they are larger, so they move more air than the standard ones at the same boost level).

They guy who bought the car in first place had issues with the engine. The seller had told him that there were no oil restrictors to the turbos and they had too much oil and that caused oil leak and other issues. But we found out that the engine was bad. The engine had alot of crankcase vent. I helped this guy to do some leakdown tests etc and we found out that the compression were bad. So i helped him to get the engine out and we saw that the engine was bad. Bought new bearings, pistons, crankcollar, rods etc and got the engine completly rebuild and also he bought these 2 new turbos (Gt2860-5). After this the car was just sitting for a few years until now when i bought it from him. 
I dont know if the HKS turbos are bad or not. They probably had to much oil cause there were no oil restrictor as recommended but they were running on low boost until we found out that the engine was bad. There are not much play in them but i dont know what the limit are for these.
Maybe some cleaning would be enough. I could send them to someone so they could check them for me. 

But these turbos should work good on standard injectors, fuel pump etc? I will try to fix an aftermarket ecu. 

On 26/07/2022 at 5:56 PM, GTSBoy said:

You've changed man.

It's to keep @Duncan from appearing to have sand in his taco when I mention throwing twins in the bin 😅

  • Haha 1
On 26/07/2022 at 3:21 PM, timmy94 said:

Yeah, i confirmed its -5. So running standard boost and standard power with stock injectors and pump on these wont be an option? F##k me

I have the 2 old one still here. 2 hks turbos i belive are gt25, cant find anything about them and the identification label are hard to read. Maybe sell the -5 new turbos and send these ones in for rebuild and fit them instead?

20220723_105805.jpg

20220723_105812.jpg

Mate as you already have the -5, just go with them. At least they are new. Go run 1.5bar and report back if you like them

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