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ok, here's my situation:

Did an RB20 build couple years back, all freshened up Rb20, all brand new internals bla bla bla, with an N1 oil pump. The first yead it went great, no major breakage, did 11.07 at 128mph.

The second year (last year) dropped it to 10.89 at 131mph, but with a major oil pump drive malfunction,

So this year, went and bought a collar, had it installed on the crankshaft. Again went with a N1 oil pump new from Nissan. Did my best so far, 10.42 at 125mph. And again lost oil pressure completely, dismantled the rb once again to fing my ''less than 20km of use'' N1 oil pump destroyed!!!!

So here's the questions to the knowledgeable people on this board:

1- Can dropping the clutch (engaging it) at 7500rpm at the launch make the ''little slack between the collar and oil pump drive'' break the pump?

2- Is there a miracle recipee (specific collar with specific oil pumps) out there that can permanently cure this problem?

3- Is it an actual oil pump drive problem or a balancer pulley (vibrations) problem like I heard from shops near my place?

4- Anyone had this problem before even with a collar?

thx for any info, and please, if you don't know the answers, please don't post anything, even if you want to tell me that there's other posts like this one.

regards

Sylvain

Edited by FastRB20

For starters, using the N1 pump for serious drag racing is not the best of choices.

TOMEI or JUN pumps are far stronger than the N1 pumps.

Then again those pumps can fail if not properly mated to the collar.

A crank that is not finely balanced will also cause you problem.

I used an N1 oil pump on my 10 second GTR for years...it survived lots of 8000 rpm launches by my wife Stacey and quite a few 9000rpm launches by myself. We turned the launch rpm up to 9500rpm and used a hard cut ignition rev limit as opposed to the soft cut fuel rev limit we used previously and it broke the 2nd pass we ran it. Running a properly balanced

engine assembly and using proper crank damper will help it survive.

lesson...use a soft cut rev limit, use a sensible launch rpm, properly balance the engine and use a better harmonic balancer.

Edited by DiRTgarage
I used an N1 oil pump on my 10 second GTR for years...it survived lots of 8000 rpm launches by my wife Stacey and quite a few 9000rpm launches by myself. We turned the launch rpm up to 9500rpm and used a hard cut ignition rev limit as opposed to the soft cut fuel rev limit we used previously and it broke the 2nd pass we ran it. Running a properly balanced

engine assembly and using proper crank damper will help it survive.

lesson...use a soft cut rev limit, use a sensible launch rpm, properly balance the engine and use a better harmonic balancer.

Agreed!

Whilst the pump might have a weakness, its as much about how you actually treat it as opposed to anything else.

Hard/sitting on the limiter is BAD and will destroy a pump, hell you can kill a JUN pump in the same way if you abuse it.

rb20 - 131mph

FARK YEAH!!!

now ive got that done with

if u want the best of the best (for non external pumps) go tomei pump with collar and ati harmonic balancer

a little bit cheaper but still fairly good go a jun pump and ross balancer

or just go all out with a external and you shouldnt have any problems (will be expensive)

You should be able to set up a wet sump external pump for not a great deal more than using a jap brand name pump. As the TOMEI pump is around $2200 aud. You can buy a peterson 5 stage pump for less than that so I would imagine that a 3 stage pump would be relativly cheaper again. Add in associated brackets and a bit of fabrication on your stnd oil pan and I would think that this could possibly even end up cheaper to set up especially if you are handy with fabricating some of the stuff yourself. and hey presto no more broken oil pumps. As it seems that your set up is for drag racing it would be quite easy and not going to pose you any danger to set up an engine kill switch that is refrenced by oil pressure to save the engine should you lose a belt etc.

You should be able to set up a wet sump external pump for not a great deal more than using a jap brand name pump. As the TOMEI pump is around $2200 aud. You can buy a peterson 5 stage pump for less than that so I would imagine that a 3 stage pump would be relativly cheaper again. Add in associated brackets and a bit of fabrication on your stnd oil pan and I would think that this could possibly even end up cheaper to set up especially if you are handy with fabricating some of the stuff yourself. and hey presto no more broken oil pumps. As it seems that your set up is for drag racing it would be quite easy and not going to pose you any danger to set up an engine kill switch that is refrenced by oil pressure to save the engine should you lose a belt etc.

yep

  • 2 weeks later...

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