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Discussion Starter #1
Ive been looking around for an aftermarket Oil Pump gear, but cant find any info on a quality piece for the 2zz. Im hesitant to buy a Circuitworx due to the tolerance issues they had with the last batch.

Im running a Ferrea valve train with the potential for revs baby, but dont want to push my luck with an OEM gear.

Any Suggestions?
 

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MartyMcfly,
I want to know the same information. I haven't had a chance to cruise the celica forums yet, but I suspect if another pump option exists, it will be posted in those forums. Perhaps Monkey Wrench Racing may be searching for a new product.
 

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Discussion Starter #3
well addertooth, lets keep eachother informed. Matter of fact, Ill give monkey wrench a call right now.
 

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The stock gears have way overhyped bad rap. They are plenty durable parts for sub 9000 rpm redlines. All these gerotor pumps hate cavitation and oil starve. Avoid the starve. The cavitation will happen on the upper revs so you really need to look at an external, under driven pump, for that task.
 

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Discussion Starter #7
The stock gears have way overhyped bad rap. They are plenty durable parts for sub 9000 rpm redlines. All these gerotor pumps hate cavitation and oil starve. Avoid the starve. The cavitation will happen on the upper revs so you really need to look at an external, under driven pump, for that task.
Turbophil,
I feel like I should be solving some sort of Math equation while reading through your response. Can you rephrase what was just said, except re-word it for someone who barely made it through highschool?

BTW- Just ordered a clutch and catch can from you last night, and a nicasil block from you last week :nanner: Excited about starting the rebuild. Phil when will you have a quality replacement?
 

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^Cool and thanks:up:


Clarification:

External Pump. Yes. It's a pretty simple kit. Available today for "kitting", not yet. But soon. It's the pressure side of a dry-sump pump (which is composed of a pressure pump and 1 or more scavenge pumps). It requires a specially designed wet sump (pan), which is part of the reason we designed our oil sump in the way we did. You can see here what I mean. The pan has a special pick-up to accommodate an external pump (or the stock pump. You run one or the toher, not both pumps). Why not a dry-sump? Packaging and complexity of a dry-sump in these motors is a major turn-off... as is the expense of a dry-sump. A wet sump with external pump completely solves the issues with our stock gerotor pump and is a ~$1500 deal opposed to a several thousand dollar deal like that of a dry-sump. It is an option only for those NOT running A/C.

Stock Gears. They are FINE parts. The stock 2ZZ fails for all sorts of reasons, but not typically from oil pump failure. Last year was the FIRST year we've built a motor due to oil gear failure, and we build dozens of motors! They were both circuitworx gear motors. I've *never* rebuilt a motor because of a failed stock gear set. Run the stock redline and your stock gear set will be fine. You have to money shift the car, or maintain a high redline, and/or oil starve the heck out of it before you'll run into problems with the stock gears. The *problem* is not the gear set, rather the pump design. Gerotor pumps like ours do not like to pump oil in the upper revs. It's a 1:1 pump (spins at same speed as crank)and oil just doesn't tend to move well after 6-7,000 RPMs in a pump. The 2ZZ pump start to cavitate in the upper revs and there's no aftermarket gear that will change that. You can help to mitigate the cavitation of the stock pump by ensuring good oil sumply, hence the baffled pans/sumps.

Summary, stock gear set is fine for <9000 RPM motors. It will handle the occassional money shift but other parts of the motor probably won't. Stock oil pump (regardless of gear set), really isn't a great design in general for >7,000 RPM sustained runs. We're all pushing the limits there running the stock pump design on the track. Rest assured the internals of the motor would be happier with a slower turning external pump running higher oil pressures on the track.

Hope that helps,

Phil
 

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The TODA gears are still powdered metal gears. I purchased a couple of their pumps and checked out the gears. Probably not as good of a part as the stock gear (certainly not better if it is as good-- might even be the same part;))...

Cheers,

Phil
 

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Discussion Starter #12
The TODA gears are still powdered metal gears. I purchased a couple of their pumps and checked out the gears. Probably not as good of a part as the stock gear (certainly not better if it is as good-- might even be the same part;))...

Cheers,

Phil

OUCH! Toda, shot down! -eek-

Phil, thanks for the well laid out response. So its not the gears thats the problem, its mainly oil starvation at high rpm's and a wretched OEM oil pan, got it.

Let me ask, with a bottom end and head built to rev upward of 9k rpm, would you recommend shying away from doing just that? I thought I had all bases covered, but this oil pump issue has me slightly concerned, although you've alleviated them for the most part.

Complete 180, Phil, I ordered the ACT XTSS clutch from you. i wanted something more durable then the HDSS. Do you think thats overkill for my bone stock tranny, and limited H.P. output?
 

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So who makes the gear for SSC?
 

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OUCH! Toda, shot down! -eek-
Toda gears are not sintered metal. The quality is very nice. We have a couple here that we have benchmarked. We also have several broken stock gears here - they are a known problem. If you are spending a alot of money on a built engine, it is nice to have a better gear. Of course the assumption is that you have a proven oil pan on your car as well...Both Toda and SSC have gears that are proven. [email protected] reviewed their testing with me and it seems solid. :up:

We are also developing our own gear- it is a real challenge. Our first version, in 4340, had some issues. Our second version was improved but still showed some wear (after 250+ track miles). The third version is coming out of the car today (I just put 250 track miles on it last weekend :shift:). We'll see what we have shortly.
 

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Eliseparts.com in the UK will have uprated EN24 (think this is the same as 4340 in US?) gears available shortly. We've been testing them on an engine dyno for a couple of months and they are in some of the UK race cars. They've been through a few variants and are made by a well known UK Motorsport Engineering company. I think they are planned to retail at less then £200

 
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