# Difference between 84-86, 87 88-89 engines



## coolxlz (Jan 8, 2005)

Is there a difference between 84-86, (87) and 88-89 engines? I was told that there was a slight different in the engine when Nissan made the 87. I can’t remember what was said to me .The reason why I’m asking the question, the timing belt broke and I’m replacing it. Also, I was told to check to see if any anti-freeze was in the oil, but did not see any. I’m trying to figure out the best route of fixing the problem and how much damage has this cause.


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## asleepz (Feb 24, 2004)

It's the VG30ET W Series which had a higher CR ratio and just a little beefier all the way around. (From what I've heard)


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## JAMESZ (Mar 12, 2004)

I wouldn't think you would blow your head gasket or any other gasket if the timing belt broke; whoever told you that is full of it. You probably did fry your valvetrain though. Basic things are the same between the engine. At best the differences are minor.


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## morepower2 (Apr 19, 2002)

SKD_Tech said:


> It's the VG30ET W Series which had a higher CR ratio and just a little beefier all the way around. (From what I've heard)


Intake ports are smaller and straighter with the same flow, better toque as well.


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## JAMESZ (Mar 12, 2004)

Torque remained the same. 88-89 had 5 more hp. But they were still rated at 227ft/lbs. The torque curve is alittle bit different, but it isn't much.


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## morepower2 (Apr 19, 2002)

JAMESZ said:


> Torque remained the same. 88-89 had 5 more hp. But they were still rated at 227ft/lbs. The torque curve is alittle bit different, but it isn't much.


Make that better low end torque.


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## AZ-ZBum (Nov 21, 2004)

morepower2 said:


> Make that better low end torque.


Got dyno charts to back that up? If you only post turbo dynos, that was solely because of the smaller T25 turbo.

Engine differences (as taken from the 1988 Nissan Product Bulletin - Vol 179):
part: Head, Head gasket, block
point to be changed and objective:
1. Addition of water holes on the head and the block. (To the exhaust side to improve anti-knocking abilityby improving water flow)
2. Modification of the port shape of the head. (To increase charging efficiency)
3. Addition of water holes and reduction size on gasket. (Addition of hole: Exhaust side only)
4. Addition of ribs to the block. (To increase rigidity)

part: Piston, Piston pin, connecting rod
point to be changed and obective:
1. Full float system (Decreased vibration level)

part: Connecting rod, Crankshaft
point to be changed and obective:
1. Increase in weight due to the increase of the sectional area of the 1 section on the connecting rod. (To increase strength)
2. Increase in the counterweight for the crankshaft due to the increase in the weight of the connecting rod.

part: Crankshaft, crank pulley, crank pulley bolt, crank pulley bolt washer
point to be changed and obective:
1. Increaseing the foward length of the crankshaft. (To standardize parts)

part: Block, Oil pan gasket, oil pan, oil pan bolt
point to be changed and obective:
1. Changin from a rubber gasket to a liquid gasket. (Better sealing properties)

part: Oil pump, rear oil seal retainer, oil pan gasket, oil pan
point to be changed and obective:
1. Necessary changes for using the liquid gasket.


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## morepower2 (Apr 19, 2002)

AZ-ZBum said:


> Got dyno charts to back that up? If you only post turbo dynos, that was solely because of the smaller T25 turbo.


We have plenty of those at work. Thats why serious professional (IMSA GTO car long time ago, some current off road racers) builders of the VG30E only use the later head.

Steve Mitchell found much better bottom end on his Z31.


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## AZ-ZBum (Nov 21, 2004)

http://www.engr.colostate.edu/~radare/wserieschanges.html


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## asleepz (Feb 24, 2004)

AZ-ZBum said:


> http://www.engr.colostate.edu/~radare/wserieschanges.html



Nice site.....


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