# redline



## hondakillerZX (Aug 16, 2004)

does anyone know any upgrades i can put on to safely raise the redline.its a 1987 300zx turbo (5 speed) if that helps i dont know.


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## asleepz (Feb 24, 2004)

cams should do it. But there really is no need to raise it. You won't make any more power with more RPMS


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## Zen31ZR (Mar 24, 2004)

SKD_Tech said:


> cams should do it. But there really is no need to raise it. You won't make any more power with more RPMS


 Maybe so , but you can go farther in each gear. I have a hard time with the rev limiter as it is now. More boost does make the VG more willing to rev. To answer his question , HKS does make a fuel cut defenser for the Z31. It's about $120. Stock fuel cut is 6400-6500 rpm , I'd like to raise it to 7000. The JWT ECU upgrade also raises the limiter to 7000.


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## asleepz (Feb 24, 2004)

is 7000 safe with 10PSI+?


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## hondakillerZX (Aug 16, 2004)

wont it give you engine damage if you redline a lot


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## Zen31ZR (Mar 24, 2004)

hondakillerZX said:


> wont it give you engine damage if you redline a lot


 Not at all. Most factory engines can withstand over 1000-2000 rpm higher than their actual redline , the redline is deliberately kept low for warranty purposes. The VG30 requires a heavier duty oil pump to maintain a constant 7000 rpm or above , but otherwise it can handle it just fine.


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## Zen31ZR (Mar 24, 2004)

SKD_Tech said:


> is 7000 safe with 10PSI+?


 If I could hit fuel cut (6500 rpm) numerous times with no difficulties at 15 psi , 10 psi would be a walk in the park.


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## TheJackal (Aug 18, 2004)

IMO head work like that is at the end of the line.. The way you raise the rev limit is putting stronger springs in the head. I have no idea how well the stock longblock can hold revs.. 

in comparision the 4g63 is limited at 7250, my buddy takes his to 9000 frequently, its totally stock except for new cams, how hes doing that, i do not know.

For mental purposes, the spring cant keep up with the revs so theres time when the vavle isnt in contact with the spring, causing it to float and possibly knick a piston...

Probobly alot of you already know this, but i felt like typing


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## asleepz (Feb 24, 2004)

yeah I knew about floating the valves I just knew it wasn't going to happen at 7K


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## KungFuGrandpa (Aug 23, 2004)

you can stop floating the valves buy lighter valve train. if you want rpms take your crank and grind down the rod journals .030 it reduces friction and will also let it rev better


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## 0341TODD (Nov 15, 2003)

so the only way to raise the stock rev limiter is to send the ecu to jwt? That sucks man- actually- for me it doesnt matter since I have an automatic- You guys might be faster then me, but atleast I can drink pepsi and talk on my phone at the same time while im driving.

Is there any other way to bypass the rev limiter?


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## Zen31ZR (Mar 24, 2004)

0341TODD said:


> so the only way to raise the stock rev limiter is to send the ecu to jwt? That sucks man- actually- for me it doesnt matter since I have an automatic- You guys might be faster then me, but atleast I can drink pepsi and talk on my phone at the same time while im driving.
> 
> Is there any other way to bypass the rev limiter?


 No , not just JWT. I also mentioned the HKS part.......


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## asleepz (Feb 24, 2004)

0341TODD said:


> so the only way to raise the stock rev limiter is to send the ecu to jwt? That sucks man- actually- for me it doesnt matter since I have an automatic- You guys might be faster then me, but atleast I can drink pepsi and talk on my phone at the same time while im driving.
> 
> Is there any other way to bypass the rev limiter?



Me too but I gotta be on the highway


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## Zen31ZR (Mar 24, 2004)

SKD_Tech said:


> Me too but I gotta be on the highway


You guys are wimps. I used to be able to drive a 5-spd while eating a burger and talking on the cell phone , in the city......


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## 0341TODD (Nov 15, 2003)

Oh yeah? well I can drink, talk , wack off and yell out the window at mexicans while driving with my wee wee- ALL AT THE SAME TIME! so f-off-lol

and thats only morning traffic

Do you have a part number for that thing Balliztik?


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## Zen31ZR (Mar 24, 2004)

0341TODD said:


> Oh yeah? well I can drink, talk , wack off and yell out the window at mexicans while driving with my wee wee- ALL AT THE SAME TIME! so f-off-lol
> 
> and thats only morning traffic
> 
> Do you have a part number for that thing Balliztik?


 Jeez do I have to find everything for you? Just look in HKSs website. HKSUSA.com. Look in Nissan , 300zx , 84-89. It's just that easy.....


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## morepower2 (Apr 19, 2002)

KungFuGrandpa said:


> you can stop floating the valves buy lighter valve train. if you want rpms take your crank and grind down the rod journals .030 it reduces friction and will also let it rev better


Hummm.... can you say zero oil pressure. Better not try to build your motor.


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## morepower2 (Apr 19, 2002)

SKD_Tech said:


> is 7000 safe with 10PSI+?


Yes, the VG is a very strong motor.


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## Zen31ZR (Mar 24, 2004)

morepower2 said:


> Yes, the VG is a very strong motor.


 And I don't think JWT would raise the limiter to 7000 rpm in their ECUs if it wasn't.


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## Zen31ZR (Mar 24, 2004)

morepower2 said:


> Hummm.... can you say zero oil pressure. Better not try to build your motor.


 I'm hoping he meant .003. .030 is a spark plug sized gap. That's way too much.


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## 0341TODD (Nov 15, 2003)

Hey Eric, I cant get that thing yet man, my distributor still hasnt finished setting up there account with HKS yet. I will try another one of my distributors though also. Bear with me dude.


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## Zen31ZR (Mar 24, 2004)

0341TODD said:


> Hey Eric, I cant get that thing yet man, my distributor still hasnt finished setting up there account with HKS yet. I will try another one of my distributors though also. Bear with me dude.


 Yeah , it's all good. Just collecting parts for the winter project. I plan to come out swinging hard next spring.


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## JAMESZ (Mar 12, 2004)

[email protected] said:


> Yeah , it's all good. Just collecting parts for the winter project. I plan to come out swinging hard next spring.


I should be hitting pretty hard to as of next spring. The valvetrain is good to 7000rpms. Around 7500rpms floating occurs with the stock valvetrain. But even though nobody listens to me with the stock valvetrain you aren't making any power after 6000rpms. It may feel like you are still pulling hard but trust me your hp is skyrocketing downward fast. Even with higher boost levels this is still experienced. If you look at a dyno sheet you will see what I am talking about. Change out the cam and rework the top end of the engine and get a good port and polish and with higher boost levels your VG will be a monster.


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## Zen31ZR (Mar 24, 2004)

JAMESZ said:


> I should be hitting pretty hard to as of next spring. The valvetrain is good to 7000rpms. Around 7500rpms floating occurs with the stock valvetrain. But even though nobody listens to me with the stock valvetrain you aren't making any power after 6000rpms. It may feel like you are still pulling hard but trust me your hp is skyrocketing downward fast.


Sure doesn't feel like it. But hey , whatever you say....


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## JAMESZ (Mar 12, 2004)

[email protected] said:


> Sure doesn't feel like it. But hey , whatever you say....


HAHAHA of course it's whatever I say lol :fluffy:


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## Marc Z31 (Jul 25, 2004)

The VG30ET WILL start getting valve float around 6800-7000 rpm. You need VALVE SPRING UPGRADES to raise redline. You really don't make as much power up there as you think. On stock heads and cams, the power starts to dip around 5200 (you still make usable power to 6000 though), I have seen dynos numerous times showing the same thing. If you want to raise the redline the right way, you will need some head work (especially around the bowl) oversized (+1mm) exhaust valves (not needed, but recomended), a good set of cams, A new ECU or stand alone engine managment, valve springs, pistons, a knife-edged crankshaft, and a good engine balancing. You CAN spin the stock engine to 7K, but the stock ECU will cut fuel at EXACTLY 7K.

Hopefully on the next build (VG33ET) I want a 7500 rpm redline...and 700 hp on 101 octane.


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## Zen31ZR (Mar 24, 2004)

Marc Z31 said:


> The VG30ET WILL start getting valve float around 6800-7000 rpm. You need VALVE SPRING UPGRADES to raise redline. You really don't make as much power up there as you think. On stock heads and cams, the power starts to dip around 5200 (you still make usable power to 6000 though), I have seen dynos numerous times showing the same thing. If you want to raise the redline the right way, you will need some head work (especially around the bowl) oversized (+1mm) exhaust valves (not needed, but recomended), a good set of cams, A new ECU or stand alone engine managment, valve springs, pistons, a knife-edged crankshaft, and a good engine balancing. You CAN spin the stock engine to 7K, but the stock ECU will cut fuel at EXACTLY 7K.
> 
> Hopefully on the next build (VG33ET) I want a 7500 rpm redline...and 700 hp on 101 octane.


I bang fuel cut at 6500 , so I think you are incorrect.  I even have a pic of it.........


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