1GGTE Single Turbo Boost

**ArthurGA70** · 18-09-2011, 07:52 PM

Hi guys,
This is my first post on here, long time lurker soaking up the wealth of knowledge. But I digress, my question is this:

What is the maximum safe boost level for a 1GGTE? I've seen on here lots of people say 14 because the stock turbos run out of puff after that (and other people say they ran ~22 of a couple days, but I'm looking more long term.) but I have a GT2860RS which I have read on the nissan forums is good up to ~21psi. I have racing piston rings which can handle something crazy like 35psi so I shouldn't have to worry about them failing and looking at the conrods, they aren't exactly small. I have sorted out the fueling system so I don't forsee leaning out as being a problem. So it is really, what sort of boost can the bottom end handle on a regular basis?

**emp?** · 20-09-2011, 09:49 PM

personally i would run 20psi without a 2nd thought, they love the boost

**Toy77** · 21-09-2011, 10:00 AM

with decent supporting gear - it is all about tuning...

There are no real weaknesses in the 1g's... so it comes down to pump fuel as a limiting factor. Personally i think 20-21psi is a nice safe limit for pump fuel - people push more, but then there is the worry of poor fuel quality, temperatures etc.... if you are driving it reguarly, safe reliable horsepower is what you want.

So i'm with Josh - a good tuner and run 20psi no probs.

Cheers
Stew

**boxh34d** · 21-09-2011, 10:16 AM

What kind of power you chasing? Are you going to need 20psi to achieve your goals, or just testing the water to know how much room you have to play with?

**1gjet** · 21-09-2011, 10:33 PM

20psi seems to be the going rate with tuners on 98, i personally have run my 1g on more for most of its life, but it has a hard life. Just running the turbo in its efficiency would be the best, better for the turbo and your engine, running any more is pointless.

**stradlater** · 23-09-2011, 01:00 PM

I ran 30psi in mine.. It wasn't a daily driver, but I did drive it on the road, with no hassles.

It did have a large turbo though....

**ArthurGA70** · 28-09-2011, 01:51 PM

Originally Posted by emp?

personally i would run 20psi without a 2nd thought, they love the boost

Originally Posted by Toy77

with decent supporting gear - it is all about tuning...

There are no real weaknesses in the 1g's... so it comes down to pump fuel as a limiting factor. Personally i think 20-21psi is a nice safe limit for pump fuel - people push more, but then there is the worry of poor fuel quality, temperatures etc.... if you are driving it reguarly, safe reliable horsepower is what you want.

So i'm with Josh - a good tuner and run 20psi no probs.

Cheers
Stew

Cheers for the info, 20psi seems like the best bet after reading what everyone has said. +Rep to both of you

Originally Posted by boxh34d

What kind of power you chasing? Are you going to need 20psi to achieve your goals, or just testing the water to know how much room you have to play with?

I have no idea as to what power numbers I will be getting, people always ask me that and I haven't set myself a goal because I don't want to disappoint myself. So the answer to that is as much as I can possibly get, I know people who have run higher, but they have also melted pistons and whatnot (something i did myself too and I don't want to blow this engine up as it isn't even finished being run in yet).

As far as tuning goes, we haven't touched ignition timing yet, just getting it to run at stoich and the turbo is coming on very quick so when it dies in the future I will no doubt be going to something bigger. The only portion of the engine that is untouched now is the head, I have 1gge cams that have been ground as aggressive as possible, I am getting vernier cam gears made up and have a spare head. I heard on the standard cams and stuff that you can rev them out to 9k no problem, I'm very interested in getting it worked so it can rev to 10k(like harder valve springs and larger valves and ports etc.) (yay double digits), but the problem is with the cams i have had to put shims in which if you rev highly is a problem for them to pop out. So if I can rev it out high I'd be interested in running large boost on a large turbo and have a bit of a lag monster but still have a bit of revs to play with. Any information anyone can give me about getting it to rev out would be very useful, including any info on if the oilpump is up to the task.

**1gjet** · 28-09-2011, 03:27 PM

Make sure you read up, there is plenty of info on shimming the oil pump, which i highly recommend and have done on my own motor, i had a stock head and would frequently visit 8800

not dramas, but with the stock cams they really suffocate up top, the cams are just too small, so there just in not enough flow getting in there. I have done cams, valvesprings and shims now and its hard to hold it below 9 when it comes on boost

It also helps if you have a gen 3 crank as they are fully counterwieghted, alot smoother ramp of revs.

**ArthurGA70** · 28-09-2011, 07:27 PM

Originally Posted by 1gjet

Make sure you read up, there is plenty of info on shimming the oil pump, which i highly recommend and have done on my own motor, i had a stock head and would frequently visit 8800

not dramas, but with the stock cams they really suffocate up top, the cams are just too small, so there just in not enough flow getting in there. I have done cams, valvesprings and shims now and its hard to hold it below 9 when it comes on boost

It also helps if you have a gen 3 crank as they are fully counterwieghted, alot smoother ramp of revs.

By shimming the oil pump do you mean putting a washer in the spring? Also, is there any way to find out what gen my engine is? It doesn't have the factory injectors or loom so I cannot look at the plugs to tell. The crank was balanced though so I don't think it should be much of an issue(?). By shims, is that the little caps that sit under the buckets on top of the valve stem to space it out for the cam lobes? Cause the guy I got the cams + shims from said that I shouldn't rev it as high cause one might pop out.

**1gjet** · 29-09-2011, 02:34 PM

Washer behind spring yes. There is a few ways you can tell but it depends if the engine is apart or not. 1ggtes are shim over bucket, them popping out shouldnt really be a problem but it all depends on the cams ramp angle on the lobe.

**ArthurGA70** · 29-09-2011, 02:43 PM

Originally Posted by 1gjet

Washer behind spring yes. There is a few ways you can tell but it depends if the engine is apart or not. 1ggtes are shim over bucket, them popping out shouldnt really be a problem but it all depends on the cams ramp angle on the lobe.

How many mm of washers would be roughly right to shim it to the right pressure? And I have a spare cylinder head so I'll rev it out and see how it goes then, It'll be useful to have that extra rpm on the track, but I won't be revving it that high normally.