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ryanman250

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Discussion starter · #1 ·
I bought a new shortblock out of a NT. It was recently rebuilt with about 2-3K miles on it now. My question is will it hold around 12-15 or so lbs of boost or about how much will it hold? Has anyone done this with a NT motor? I'm gonna do it anyways and see how long it lasts. Search turned up a bunch of useless crap that was off topic.
 
Aside from the compression change and lack of a knock sensor, and the fact that the internals arent quite as strong, I wouldnt give it forever at 15psi, even with mods to support it, like timing control, egt, lower compression pistons (lower to 8.5) and stronger rods. I'd like to hear how it goes, but I doubt it will be anything amazing.

Why are you putting an NT shortblock into a GSX?
 
There is a mounting tab between the #2 and #3 cylinders on the back of the block to which you can put the knock sensor. I read on the Talon Digest Archives that it will work the same way. But you still have high compression pistons so that would be a problem. Why don't you change them to turbo ones??
 
Discussion starter · #4 · (Edited)
That motor is all I have at this time. I can change the pistons but I want to get a set of 2G pistons but every time I find some I talk to the person and they are like umm I sold them an hour ago. I think most of them people are lying. If I could get ahold of some 2's I'd put those in. Also I was asking about the nonturbo pistons cause if you didn't know "more compression=more power". I was wondering if anyone had used the before. Their made from the same stuff as turbo pistons but higher compression ratio.

Also I had to pull motor out cause it melted a piston 2 hrs after I put 16G on. It screwed up the cylinder wall pretty bad. I would have to bore at least .040 over and I'm gonna save it for a project.
 
Yes I know that more compression = more power. But it also means "more tuning and more fuel". There are a lot of guys runnig high compression pistons on their DSM(JG 9.0:1 pistons for example), but they have an upgraded fuel system and stuff like that in other to keep the motor as one. If you drop the block in there with a 16G at 15 psi, without added fuel or the like you will be lucky if you just melt just one piston. Just be sure to keep the boost at a safe limit, add the corresponding fuel, and tune it correctly or you will be swapping engines again very soon.:cool:
 
Discussion starter · #6 ·
I got a set of 450cc injectors and I rewired the fuel pump and have an adjustable fuel pressure regulator. I don't necessarily want to run 15 psi but occasionally may run it only at the track. I also got some 2G stock turbo pistons and I gotta pick them up this weekend. I'm gonna go ahead and put the 2G's on my 1G rods. How much boost can the 2G pistons hold? Also what should I set fuel pressure to? Any tips would help.

Thanks
 
If you are putting in the stock 2g turbo pistons on 1g rods you will be fine with 15psi on pump gas. No need to upgrade fuel injectors(450cc is stock size).
Keep the fuel pressure the same as stock.

The 2g pistons can handle the boost as long as you have the correct fuel to go with it. If you plan on getting over 400(ish)hp out of the engine you need to worry more about the rods.
 
Don't forget to put the knock sensor on the #3 cylinder boss. It will work the same as on the Turbo block. Check out this link.

Kyle at Blackhole Performance did the same swap:http://207.154.72.181/archives/m/1999/12/19991223.txt/14.html

As for the oil squirters, you might want to check at Magnus Motorsports site. Magnus seems to left out the oil squirters from all the engines he assambles(sp??).
 
ryanman250 said:
That motor is all I have at this time. I can change the pistons but I want to get a set of 2G pistons but every time I find some I talk to the person and they are like umm I sold them an hour ago. I think most of them people are lying. If I could get ahold of some 2's I'd put those in. \
2G pistons never last long. I sold my set in an hour. I regret it, and want another set, but teh only place to get them is the dealership. They're a very hot item.
15 psi on high compression pistons will be more powerful than it would be with 2g or 1g turbo pistons. I would be very wary of running with them at that high a boost level. As a general rule, when people turbo a stock block NT engien, they don't run over 7-9 psi. It doesn't take long to melt a piston, and you can't watch your guages all the time.
 
Engine was bought from me :)

Ryan,

You can drop the engine in just like it is, but be careful with boost. Your best bet is to leave the block assembled and only install the pistons and rods. Look up and find the exact clearance for the 2g pistons on 1g rods. Go to www.vfaq.com I also recommend getting the rods shot peened and polished. This will make them stronger. After this is completed, put the knock sensor in and the pistons back in. That block is a 6 bolt and in good shape. It is the same as every turbo 6 bolt minus; squirters, knock sensor and turbo pistons. If you decide to keep the nt pistons in, that is fine too. Just remember that with the big 16g, and 9.1 pistons, you will need more fuel. If you dont use the squirters, this is your choice. I just think that if they came with the turbo block, they are needed. The choice is yours. Like I told you earlier, let me know how everything goes. I would also recommend a set of arp's and the stock head gasket.
Good luck.
Robert
 
Higher compression is fine even if you up the boost. The thing tho is it becomes extremely sensitive to knocks compared to lower compression. If you are a great tuner and know what you are doing, pushing 20+psi is possible. However, do something stupid means more $$$ to do repair :D
 
Discussion starter · #16 ·
I got a set of 2G pistons and a set of 450cc injectors. Gonna go pick them up tomorrow. I'm also ordering the ARP bolts and I got a Mr. Gasket head gasket. I'm gonna take everything monday to the machine shop and should have my car back together by next weekend for the NOPI show at Rivercity in San Antonio. All I need now is a torque converter. I got a guy in PA that says he has one but I just mailed him back to make sure its for an AWD. Is the AWD torque converter the same as a FWD? Anybody know? Also I think I'm gonna order a set of cams also. Any suggestions?

Thanks, Ryan Morris
 
Don't go with Mr. Gasket for the head gasket!! Use the OEM one, it comes in 2 styles: normal one and the metal one. You are going to be runnig higher compression now, so it's best to stick with one that is going to withstand the abuse. As for the cams, you can drop a set of 1G manual ones, or a Web Cam (street grind) setup or the HKS ones. I have the later ones and I love them..:D
 
This is my screen name I promise. I have been bustin it. I think I have lined up 2 jobs. One at the local chemical plant and the other at a local speed shop. The guys at the speed shop(Mayhem Performance), need someone that knows a thing or 2 about DSM's. I spoke with him yesterday and he said come on over. As for the Dejon Intake, I dont remember the part number. It is the one that has a 3 in intake and 2g mas. This is all I know. Sorry to get off topic, I just had to clear up somethings.

Ryan,
Just like the others have said, dont use anything other than oem head gaskets. You told me something about using a copper one. I dont remember why, but dont use it. As for cams, get the HKS. Either 264/264 or the 264/272. I recommend the 264/264. You can get them from RRE for good prices.
One last thing, you are going to need some kind of fuel control. I recommend the afc and a datalogger. You may also want to get an afpr. It all adds up. Good luck. I want to see some timeslips when you get them. If you need any help tuning, let me know. JW is the $hit at tuning.
 
You can not use the 1G nt pistons. Let's think for a minute. Power is basically a function of combustion chamber pressure. More pressure=more power. Energy can not be created or destroyed (Newton), so it has to go somewhere. Voila inceased thermal energy is a result.
The hotter a given metal is the more it will expand.

So the pistons on a turbo car are going to need a larger clearance to the cylinder wall. The end gap on the rings must also be larger, or the ends will but together.

To put it in a nutshell if you simply bolted in a 1G nt block the pistons would score the crap out of the cylinder walls.


Not to mention the ring lands are smaller are on the NT pistons and will crack at the slightest bit of detonation.


Of course if you looked in chapter nine of your service manual for 5 minutes this would be old news.
 
I disagree with you nick.

I dont think it is a good idea, but it was done many times with hondas and acuras. Granted it isnt the best idea, but as JW says you need to tune it properly. I know it can be done, but if I would do it....I dont know. Just like Magnus doesnt use the oil squirters. These came with the turbo car, not the nt. And Magnus doesnt use them. Like I said, the choice is yours.
I will tell you what I do agree with;

If you have you have to ask the question here, dont do it.

Just my .02 cents.
 
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