Hks Gt2530 Or Garrett 707160-5

[tazsgtr]

I was considering replacing the stock turbo on my R32 with the Garrett 707160-5, which I know is bigger than the R34 N1. I have two questions:

1. After reading about all I could find on the 707160-5, I was under the impression that you could basically mount these on a relatively stock car (I have a 1989 R32 GTR with aftermarket exhaust, no cat, after market pod intake and after market ECU). I was advised by a shop that I would have to change my injectors, ECU and cams or have a good chance of blowing the engine. It this true? If this is true, then I will likely go with the Garrett 707160-7 b/c I really don't want to upgrade things at this time. Don't get me wrong, I want a turbo that will support up to 500 BHP for when I make the modifications later. But if I have to modify those other parts now then I will just stick with the 707160-7, which should be able to flow 450 BHP.

2. I've reviewed the R32 GTR Manual and the removal and install does not look that complicated but I was advised that it could take at least a day or even two (depending on how badly things are rusted and seized). It this an accurate estimate. From the manual, it looks like it shouldn't take more than a couple hours. I assume that there are coolant lines that I need to remove as well so are they taking into consideration the time to drain the coolant and oil?

Any assistance would be greatly appreciate. Thanks.

[Mr. Keets]

tazsgtr

I had the -5s installed on my 89 GTR late last year and i'm very happy. but

Mounting them.

These turbos are advertised as a direct replacement for the standard item. I didnt do the work but i believe they are a "straight forward" fitment

Change injectors?

I didnt originally but it did make it a bit more difficult for my tuner. My R was tuned to 410 rwhp with the original fuel system , then virtually the same figures (412) with the new fuel system (injectors, pump) however, power feels more linear with the new fuel system. The 89 pumps are getting old now and i was running the injectors at a high duty so if i was to go down the same path again I would go for some larger injectors and a pump at the same time as the turbos.

Cams?

I run some adjustable cam gears on original cams. If i was going that way i would probably go for some Tomei Poncams...but others here may say otherwise. New cams...nice to have i suppose, but i wouldnt consider them in the same light as injetcors and a pump. Infact depending how you go with cam seletcion, expectations and power levels you might be shortening the life span of your combo by using bigger cams

ECU and Exhaust

I would be going for a tuneable ECU and the rest of the exhaust before i spent the bucks on new turbos...Unless you blew one or both up

I will only tell you what i did and what worked for me...Power FC, adjustable cam gears and full exhaust including dumps. Then the bug bit so i went with the turbos and fuel system. Dont forget your clutch.

Hopefully some of the gurus will help you out a bit more technically...good luck with the R

[R31Nismoid]

If your going to upgrade turbos, you need management and possibly injectors depending on what you want out of it.

Thinking you cant is dangerous.

[tacker]

Taz,

I am the first to admit i am not expert but i have read just about all the forum threads and from what i read the stock internals are good for 500HP.

The matter of changing injectors and pump to suit your uprated turbo's is more like insurance, as you will push more air into your engine you will need to be able to push a simular % increase of fuel. Are you sure your old fuel system is up to the job after so many years of service.

High duty cycle on your injctors is bound to let you down as some stage and a lazy fuel pump is just a good way to run up a rebuild bill. The fuel pump upgrade is the easy part it will not take more than a few hours to drop a new in tank pump. And you will have peice of mind for about $250 with regards to pumps.

ECU, funny i have just start to learn self tunning as there is no other option here in the middle east. But i put the wide band AF ratio meter on this week and found the engine to be running leanish on a stock ECU, again a good way to run up a rebuild bill.

Ordered a Apexi PFC so i could adjust the fuel mixtures ( after a little drama with the PFC that is ). But is running well now. Cost about $1000 delivered

Cams i have no idea how stock cams could damage your engine with regards to more boost being forced into your engine with the larger turbo's on. I dont believe that for a moment. Still good mod to have if you want to get all the HP out of your engine could develop with more boost, and i am sure they would suit your other mods if you desided that was the way you wanted to go. But not a must have like your fuel pump, injectors and Apexi PFC or other bands of ECU.

My very new 2cents worth

[tazsgtr]

Thanks for replies. I actually blew out at least one turbo. I was doing about 50k and wasnt' even really boosting at the time. I could hear something was not quite right b/c as I stepped on and let off the accelerator, I could hear a rattle. Slowed down to 30k and then went to slowly accelerate and heard a pop and a lot of loud rattling. I'm checking the engine now to see if I damaged the rings or valves.

I was thinking about getting a bigger fuel pump or an auxillary to boost fuel pressure. I would not change the duty cycle but just increase the fuel pressure to flow more fuel through the injectors when they are open.

I have an aftermarket exhaust, no cat, aftermarket intake pods and ecu. Not quite sure which ecu but I know that boost never went over .7 bar.

[R31Nismoid]

I think it would be good to find out what ECU

just because there is more boost doesnt neccasarily mean thats a result of the ECU