Tomei oil pump failures

[HarrisRacing]

Tomei oil pump failures

I tried searching but ran across the spline drive oil pump conversions and hadn't really heard bad press about the Tomei oil pump until then. I read about ONE failure so far and the thread did not provide Tomei's resolution to the pump issue so I'm curious if this is actually a potential problem or not.

I have a Tomei pump and am curious if anyone has seen one broken and under what circumstances. I'm limiting my car to 8k, but I do bang the limiter quite frequently and was just thinking about going a bit higher soon. Some say the cause of failure is oil cavitation from temporarily starving the pump (which means a dry sump would be the only real cure), and some say it's simply the 2-flat-drive stock pump orientation that kills oil pumps. I'm looking for actual evidence if possible because I'd like to live the rest of my engine's life in a happy state of knowing the chances of oil pump failure are very slim.

Patrick

[Meathead]

If that Tomei pump failure was with the spline drive fitted then there lies your answer. They will not tolerate any misalignment and will load the driven gear radially and also fretting/galling on the splines. 

Nitto wrote a good answer somewhere on here why they will not release a spline drive yet due to reliability issues.  

You have the stroker crank with full width pump drive I guess, what sort of balancer are you running. I've been running a  1000hp ATi for a long time now, and when I pulled it all down for some checking last year it was all good with minimal wear thanks to ATI, but no limit bouncing here.  .

However if you like bouncing on the limiter a bit then something will eventually give ...dry sump it and you can bounce of the limiter all day long  

[KiwiRS4T]

I have never heard of a Tomei pump failing (which is not to say it doesn't happen). If you fit oil restrictors when you fit the pump and you overfill the sump by a litre OR preferably have an enlarged sump there is no reason why your pump should starve (i.e. a dry sump is not mandatory).Stop limiter bashing. Raise the limit on your ecu (I assume you have an aftermarket one) and put a stop under you accelerator pedal or adjust the limit stop (depending on your set up) to limit the revs.

[sneakey pete]

How would a stopper under the pedal limit revs?
 

Anyway, if it goes over 9000 that gives you another 1000rpm before you hit the limiter, just don't limiter bash it.

 

[HarrisRacing]

I do have Tomei head restrictor, Greddy Sump (Which the Tomei tells you quite clearly you shouldn't run in some of it's settings without a larger sump), and N1 block (which has larger drain ports back to the pan), also mine's baffles and rear "drain" if anyone cares about that anymore. And I'm on the Fluidampr balancer (seems really nice).

Also yes Haltech...I hit the 2 step limiter when launching everytime but if I spin the tires the car racks out so fast in first that it hits the limiter quite quick on top. It IS a soft touch limiter though which at least isn't as hard as a hard cut. I'll bump the revs to 8500-8700 and use Haltech to output a shift light and try to just stay off of it. But yes thanks for the info. Also I do have the Haltech reading oil pressure and use the "engine protection" feature to put it in limp mode when it senses oil pressure low or high out of range.

I'm not sure the guy was spline drive, but I ran across the thread (not on this forum) after someone asked me if I had converted mine to spline drive.

And yes BC billet stroker crank. Engine runs really smooth with the balancer, crank, heavier nismo coppermix, etc.

Thanks!

[Frracer]

They have in some cases become oval and caused binding and lock up of the oil pump. Nothing to do with Spline Drive. We do however have Spline Drive upgrades for most pumps and the theory they bind due to crank flex is just a myth. Both ourselves Supertec and Spool have been selling these for the past 4 years. Zero gear failures reported to date for our kits.

 

 

Edited July 21, 2018 by Frracer

[Frracer]

[Frracer]

On 1/4/2017 at 3:10 AM, Meathead said:

If that Tomei pump failure was with the spline drive fitted then there lies your answer. They will not tolerate any misalignment and will load the driven gear radially and also fretting/galling on the splines. 

Nitto wrote a good answer somewhere on here why they will not release a spline drive yet due to reliability issues.  

You have the stroker crank with full width pump drive I guess, what sort of balancer are you running. I've been running a  1000hp ATi for a long time now, and when I pulled it all down for some checking last year it was all good with minimal wear thanks to ATI, but no limit bouncing here.  .

However if you like bouncing on the limiter a bit then something will eventually give ...dry sump it and you can bounce of the limiter all day long  

Nitto are not the authoritative answer on oil pumps or spline drives. Can respect their own findings maybe it wasn’t so successful based on what clearances and spline profile they tested with. We carried out our own R&D prior to launching them in 2014. We have successfully been selling spline drive kits for almost 5 years now with over 900 kits sold and yet to see the “Nitto theory” come to life..... Ironically our Jun kit fits the Nitto pump. Have a good few customers running a Nitto pump with a spline kit. That in my view is an anwesome pump because Nitto did use better materials and a billet 7075 back plate compared to Jun/Greddy.

Edited December 24, 2018 by Frracer