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Discussion Starter #1
Ok, well I've been thinking about the future, and what kind of money I really plan on spening on my car, and what I want out of it. I've decided as of now that staying N/A is the way to go, I just don't really need all kinds of power that a turdbo or swap would give me, and I want absolute reliability. So I figured I'd go ahead and plan on finally getting a hotshot header, an SE-R throttle body, maybe some 11:1 pistons, the JWT ECU, and the cams, to compliment my exhaust, intake, and pulley, and just be done with it and enjoy what I have on the street and on the autox course (and the road course when I get my cage and harness). Inside engine work like port&polish, etc. are a possibility, but not for certain. So I guess my question is, do I risk breaking anything with these types of mods? Should I also look into reinforcing my engine just in case? I wouldn't think so since I won't be making all that much power, but I want to be sure so I can do what I must to retain the reliability. Also, for those of you who may have some experience in this area, have any wild guess on what kind of power I may make from the above mods?
 

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Destroyer of Engines
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Frist off I'm not an expert or anything, but unless you go for turbo or NOS I don't think you need to worry about reinforcing your engine. As far as power from the mods, you can check out the engine section at sentra.net, they have dyno charts for most of the mods your talking about.
 

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Platinum
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I know one GA16DE in Japan had 149HP at wheel with all the work done to it. (head work, higher compression, etc) but he blew the motor up after the while... You "must" run high octane gas for sure.... (premium gas from the pump probablly is "NOT" enough with 11.1 compression). Other than that, I don't know....
I wish someone made metal head gasket for GA motor..
 

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Icy Hot Stunta
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2,366 Posts
CarbonBlack200 said:
I know one GA16DE in Japan had 149HP at wheel with all the work done to it. (head work, higher compression, etc) but he blew the motor up after the while... You "must" run high octane gas for sure.... (premium gas from the pump probablly is "NOT" enough with 11.1 compression). Other than that, I don't know....
I wish someone made metal head gasket for GA motor..
My car runs fine on 91 octane at 11:1. The ecu just needs to be tuned for it.

Mike
 
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Discussion Starter #10
myoung said:


We have the best info on Sentra.net and NPM,,,,,
I've read everything available more times than I can count, it's just that nothing really directly said, 'if you plan on doing this, you want to reinforce this' So I figured I'd just come out and ask. I was really hoping that SCC article on the mather motorsports sentra would have new dyno numbers though, it seems like they just took everything right from his site.
 
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Mike,
So I can go with the 11:1 cr pistions and just send my JWT ecu in for reprogramming to run on pump gas? Here in the South we have 93 octane gas. That's what I was worried about was the car running well on pump gas.

On the subject of JWT ecu's.........I do have a bone to pick. I just can't understand why JWT couldn't overwrite the damn knock sensor program from my ecu (SE-R) when they reprogrammed it, seeing as B13 GA's don't have knock sensors? That is the only code that comes up when I run a system check. Ben at JWT never did call me back about this. Just a little curious.
 

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Driver
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736 Posts
Well, from reading mathermotorsports' site, I came up with the conclusion that the connecting rod bolts are the weak point in the engine. So if you have to reinforce anything, reinforce those:)
 

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Dan the car meet man
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404 Posts
I've been talking to DPR for a very long time about building a GA16DE. He said it's doable. A stage VI head with pocket porting and raising the compression in the head by shaping and re-welding the combustion chamber plus all his other things that he likes to do will cost $1000. He told me that he could probably get the intake-exhaust ratio to 78% and he can raise the compression to 10.5:1 and maybe up to 10.8:1. I also asked him about the JWT cams and he said he can build the head with the cam specifications: .345" lift 263 degrees duration @ .016" valve clearance

I also talked to him about me getting a SE-R throttle body port matched the intake manifold and then porting the intake manifold to match the intake ports. He'd charge $100 for that if you get the head done by him. Total cost, $1100, a very very good deal.

In addition to all this, Dan said with those cams and his headwork with the TB & IM that little sentra will fly! I agree with him, especially after looking at the gains on Sentra.net with just the cams and the JWT ECU.

I plan on going NA if everything works out right. And don't forget, we've got VTC! Gotta have it! The Flatter wider powerful powerband.
 
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Discussion Starter #14
dho said:
I've been talking to DPR for a very long time about building a GA16DE. He said it's doable. A stage VI head with pocket porting and raising the compression in the head by shaping and re-welding the combustion chamber plus all his other things that he likes to do will cost $1000. He told me that he could probably get the intake-exhaust ratio to 78% and he can raise the compression to 10.5:1 and maybe up to 10.8:1. I also asked him about the JWT cams and he said he can build the head with the cam specifications: .345" lift 263 degrees duration @ .016" valve clearance

I also talked to him about me getting a SE-R throttle body port matched the intake manifold and then porting the intake manifold to match the intake ports. He'd charge $100 for that if you get the head done by him. Total cost, $1100, a very very good deal.

In addition to all this, Dan said with those cams and his headwork with the TB & IM that little sentra will fly! I agree with him, especially after looking at the gains on Sentra.net with just the cams and the JWT ECU.

I plan on going NA if everything works out right. And don't forget, we've got VTC! Gotta have it! The Flatter wider powerful powerband.
So does he intend to use the stock pistons after increasing the compression ratio that way? I'm a little confused on that part, it sounds like yes. What would happen if we send him the head and get it done with the JWT cam profile and put it back on before we get the cams? Also, for the IM, do you have to send him the throttle body too?
 

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Dan the car meet man
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404 Posts
adam said: So does he intend to use the stock pistons after increasing the compression ratio that way? I'm a little confused on that part, it sounds like yes. What would happen if we send him the head and get it done with the JWT cam profile and put it back on before we get the cams? Also, for the IM, do you have to send him the throttle body too?
He intends to use the stock pistons and stock everything except the head. The head would be worked on and he said it should run fine without the JWT cams even with the head made for the JWT cam profile. If I remember correctly, the JWT cams are designed to be used in a stock head without modifications so it should work the opposite way (build the head ready for cams and then when you're ready put in the cams and do the ECU at the same time). Yes, for the $1100 price, you will have to send a GA16DE head, Full intake manifold dissassembled & cleaned, and throttle body (jumping from 48?mm or 50?mm to a 60mm). If you choose the $1000 route you just send the head. (It's a really good value to get it all done at once, just sending the intake manifold to Extrude hone would cost over $300. DPR usually charges $200 for the porting.)

This setup that I've been talking to him about was designed for the most amount of HP and TQ for an automatic sentra. He would design it where there would be no loss on bottom end and as much effeciency as possible for optimum hp & tq all the way through the powerband, unlike a peaky 5500rpm& up powerband like N/A hondas. Basically, he'd design it where the useable daily driven powerband is optimized. (This also helps with reliability, you're not going close to redline just for some power, keeps the bottom end from getting over revved. If I remember right, the stock motor is not designed to go very high rpms every day. Even with the JWT upgrade which raises the redline even more. The internals are made to go only to a certain rpm and then they get harmonically unbalanced.)
 

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Dan the car meet man
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404 Posts
Hello everyone,

I made a mistake on the prices for the DPR headwork. Here they are:

Stage IV $850
Stage VI $1200 W/ Manifold
Stage VI $1500 Full welding and combustion chamber modifications
Stage VI $2300 - added valves and coating etc
 
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