Replacement valves for 2GR-FE

[speropagos]

I recently over-revved my engine, and will likely need to replace some valves, are these stock Toyota parts or are they modified/upgraded and required to get directly from Lotus? TIA

 

[silent cilantro]

As far as I know they are factory Toyota parts. Lotus leaves all internals alone and just adds the superchargers.

 

[Tomwa]

Opportunity knocks to move to a lighter valve and springs that will let you rev the motor out more

 

[scv]

I recently over-revved my engine, and will likely need to replace some valves, are these stock Toyota parts or are they modified/upgraded and required to get directly from Lotus? TIA

How are you going to confirm valve damage-leakdown test, compression test, boroscope view? Please let us know results; would be interesting to know since there has been some discussion whether or not the 2GR-FE is an in- terference or non interference setup..........also,ECU readout could show max rpm reached and be of some interest depending on what damage if any occurred...........

 

[MIGZ]

I would see what the dealer says,

If they don’t cover it , grab a low mileage used engine and swap over everything.

That could be a fun project

 

[NorCalEmira]

JUBU has the parts you'll need to accommodate higher revs in the future

 

[speropagos]

JUBU has the parts you'll need to accommodate higher revs in the future

They definitely come highly recommended and are out for the holidays for the next 2 weeks. I've sent them a couple emails, but haven't heard back yet. Have you heard much about Monkey Wrench Racing? Are they a good alternative or just wait for JUBU?

 

[speropagos]

Opportunity knocks to move to a lighter valve and springs that will let you rev the motor out more

Opportunity knocks to move to a lighter valve and springs that will let you rev the motor out more

I'm definitely at a crossroads, considering the following options:

- replace only what's needed and maintain stock performance ($3,000 - $5,000)
- swap with performance heads, valves, springs, etc, to step up the BHP ($5,000 - $8,000)
- swap with performance long block to ensure any and all stressed & damaged parts are replaced, add significant BHP ($12,000 - $17,000)

the lower number is getting parts from Monkey Wrench Racing the higher is JUBU, with labor included for each scenario

 

[speropagos]

How are you going to confirm valve damage-leakdown test, compression test, boroscope view? Please let us know results; would be interesting to know since there has been some discussion whether or not the 2GR-FE is an in- terference or non interference setup..........also,ECU readout could show max rpm reached and be of some interest depending on what damage if any occurred...........

here's what happened... I downshifted to 4th, wanting to go back to 5th and unfortunately mis-shifted into 3rd, causing SUPER HIGH revs at a very high speed, kicking the rev display to the limit. The car immediately went into limp mode and once on the side of the road it died. It was Sunday and had it towed to a friends shop nearby, I had to start it to turn off the auto parking break and it ran pretty rough. Once there, he was able to see that 2-4-6 were mis-firing, the next day I had it towed to the dealer. Assuming that my mistake would not be covered under warranty, and the long 30-60 day wait at the dealer, I opted to bring it to another shop for evaluation. They did a smoke test with no failures and a compression test resulting in no compression on 2-4-6.

After discussions with MANY who know a lot more than me, the valves are most likely bent, and won't know any further damage until engine is dropped. So, I've got 4 options, which I responded with 3 in another reply, but will lave them here too:

- replace only what's needed, likely just OEM valves, and maintain stock performance and HOPE no other parts have been over-stressed and are just not detected yet ($3,000-$5,000)

- swap with performance heads, valves, springs, etc, to step up the BHP and still HOPE no other parts have been over-stressed ($5,000-$8,000)

- swap with OEM long block to ensure any and all stressed & damaged parts are replaced, maintain stock BHP ($8,000 - $14,000)

- swap with performance long block to ensure any and all stressed & damaged parts are replaced, add significant BHP ($12,000 - $17,000)

the lower number is getting parts from somewhere like Monkey Wrench Racing the higher is JUBU, with apx. labor included for each scenario

 

[NorCalEmira]

I'm definitely at a crossroads, considering the following options:

- replace only what's needed and maintain stock performance ($3,000 - $5,000)
- swap with performance heads, valves, springs, etc, to step up the BHP ($5,000 - $8,000)
- swap with performance long block to ensure any and all stressed & damaged parts are replaced, add significant BHP ($12,000 - $17,000)

the lower number is getting parts from Monkey Wrench Racing the higher is JUBU, with labor included for each scenario

MWR has a solid reputation for Toyota builds. JUBU has strong credentials for Lotus applications and the ability to deliver a turn key solution including a custom ECU but you'll pay a premium for that. Then again, you'll need an expert tune to get everything running the way it should. I'd consider both vendors if I was in your spot but it does seem a shame to rebuild to factory spec with the amount of labor you'll pay either way and I'd want a complete solution.

MWR offers porting and a lightweight titanium valve train upgrade that looks appealing. I'd ask Jubu if they offer the titanium parts as an option. I know they also have heavy duty spring and porting available. I you can swing a full long block replacement with forged internals, that would obviously be an amazing set up if you plan to chase HP. A happy medium might be a replacement of upgraded heads that have been ported with the improved valve train parts. If you think you'll want the upgraded bottom end later, you might want to just get it out of the way. Consider how long you want to keep the car and your intended use case. You'll make the right decision for your scenario but to get the most of any upgrades, make sure you have everything you'll need including the right tune.

 

[speropagos]

MWR has a solid reputation for Toyota builds. JUBU has strong credentials for Lotus applications and the ability to deliver a turn key solution including a custom ECU but you'll pay a premium for that. Then again, you'll need an expert tune to get everything running the way it should. I'd consider both vendors if I was in your spot but it does seem a shame to rebuild to factory spec with the amount of labor you'll pay either way and I'd want a complete solution.

MWR offers porting and a lightweight titanium valve train upgrade that looks appealing. I'd ask Jubu if they offer the titanium parts as an option. I know they also have heavy duty spring and porting available. I you can swing a full long block replacement with forged internals, that would obviously be an amazing set up if you plan to chase HP. A happy medium might be a replacement of upgraded heads that have been ported with the improved valve train parts. If you think you'll want the upgraded bottom end later, you might want to just get it out of the way. Consider how long you want to keep the car and your intended use case. You'll make the right decision for your scenario but to get the most of any upgrades, make sure you have everything you'll need including the right tune.

Thanks for your input, I'm leaning towards the "happy medium" option with MWR, ported heads & improved valve train. I have a local guy that's already tuned a handful of these so I'll lean on him to tweak the ECU. I've been using it as my daily and plan to drive it 75% of the time, so reliability is more important that pushing the envelope of performance. A basic tune getting in the upper 400's would be MORE than I need on a daily basis, but would good have when I want it, along with a higher rev range.

 

[scv]

here's what happened... I downshifted to 4th, wanting to go back to 5th and unfortunately mis-shifted into 3rd, causing SUPER HIGH revs at a very high speed, kicking the rev display to the limit. The car immediately went into limp mode and once on the side of the road it died. It was Sunday and had it towed to a friends shop nearby, I had to start it to turn off the auto parking break and it ran pretty rough. Once there, he was able to see that 2-4-6 were mis-firing, the next day I had it towed to the dealer. Assuming that my mistake would not be covered under warranty, and the long 30-60 day wait at the dealer, I opted to bring it to another shop for evaluation. They did a smoke test with no failures and a compression test resulting in no compression on 2-4-6.

After discussions with MANY who know a lot more than me, the valves are most likely bent, and won't know any further damage until engine is dropped. So, I've got 4 options, which I responded with 3 in another reply, but will lave them here too:

- replace only what's needed, likely just OEM valves, and maintain stock performance and HOPE no other parts have been over-stressed and are just not detected yet ($3,000-$5,000)

- swap with performance heads, valves, springs, etc, to step up the BHP and still HOPE no other parts have been over-stressed ($5,000-$8,000)

- swap with OEM long block to ensure any and all stressed & damaged parts are replaced, maintain stock BHP ($8,000 - $14,000)

- swap with performance long block to ensure any and all stressed & damaged parts are replaced, add significant BHP ($12,000 - $17,000)

the lower number is getting parts from somewhere like Monkey Wrench Racing the higher is JUBU, with apx. labor included for each scenario

Thanks and appreciate info; essentially confirms interference motor. Sorry for your situation and hope your recovery is "tolerable". Your 4 options cover plight nicely.............

 

[Tomwa]

For the cost I would look at happy medium.

The full build is only really going to be a good choice if you intend to push power, but even then your limiting factor is going to be the transmission. (At least according to Jubu).

If you think "hey I can drop another 15k into a Hollinger transmission at a later date" then sure. Go full build on motor, get it bullet proof for later power goals. But I don't think many people are looking at 700-800hp Emira plans.

If you are doing a "gotta fix, but while you are in there". Valve and Head work isn't going to all of a sudden turn your engine into a monster. It would need other supporting mods.

No matter what, it will be some additional spend and work. You probably could run a stock tune on new springs and valves and the most modest of porting. It would not be the happiest camper, but likely possible, stock tunes are pretty forgiving in a wide range of operation. All those changes will just mean better air flow in and out. All the sensors will notice more airflow for the density and accordingly add more fuel.

Unless you are changing the cams as well the stiffer springs won't matter much to idle.


In this slippery slope. Let's say you get valves, springs, porting. To make full use you are looking at an engine management of some kind. It is unclear if this could be covered by a flash of the factory ECU or you are moving into a Link/Haltech/Motec/Syzecs situation.

-Those will be additional thousands of dollars. Whether initial cost in the latter or all in with installation and tuning.

-For argument sake. The new valve job opens up the 2GR to revving out to 8500 rpm. Do the fuel injectors have enough overhead to provide fuel for that? How much boost is the supercharger making at 8500 rpm? How much power is too much for the pistons? 450hp? 550?How much is too much for the transmission? Will you be getting a new clutch? (Another 350+ dollars plus install)

 

[JonFuller]

JUBU say that the pistons & rods are the weak link (disregarding transmission power limits for now), and that torque is the piston killer, with their limit being circa 500nm when using stock pistons & rods.
Their Syvex ecu @ 440hp, peaks at 504nm.

The next tune up, is 460hp, but they fit a larger SC pulley to reduce peak boost. The 460 torque curve stays flatter up to a higher rpm than the 440 giving the extra 20hp right at the top, but peak torque is only 494nm

So on paper, the 440 potentially pulls a fraction harder through the rev range than the 460, with the 460 only being of benefit when you're really wringing its neck (on track?)

Main other physical difference on 460 is the tubular headers and single sportcat 200.
They extend the lambda sensor cables, and have all 4 sensors mounted at the single sportcat (so the two sensor banks are actually sniffing the same gas, they just don't know it, or rather the ecu doesn't)

So the next step from 460 is 500, which gets the forged rotating bits, but costs 25k.

With the stronger pistons & rods, they say the motor can take north of 600hp

 

[GRP]

Save your money and just replace with stock parts or heads if there was that much damage which it doesnt sound like there was.
If you are trying to eek every bit of hp out of the car for track use then sure, do a long block or built internals but otherwise the factory long block will live at 500hp all day long providing its on a good tune.
The only internal engine change in my 520whp track car is cams, springs and retainers.

 

[Tomwa]

I'm skeptical about Jubu's claims. You can find people who do junkyard 2GR builds with turbos producing 20+ psi. 700+ HP. Maybe you say "that can't last long", and perhaps not. Though given they are starting with a used engine that had a ??? Life before?

Unless there's some magic recipe that you have to use a 2GR from a different generation of vehicle it seems to me 3.5 liters of engine should be good for some power.

I will grant however RPM limitations can be very different than cyl pressure. So you may see something like the tensile strength of the rod, or rod caps won't do 8-8.5k rpm even if the head is theoretically good for it.

I know Frankenstein motors does a lot of 2GR MR2 builds, even managed a 400hp N/A 2GR. Though I think that's got higher comp ratio pistons out of the fks version of the block.

 

[NorCalEmira]

The 2GR platform is stout from the factory and capable of delivering an exceptionally long service life. These motors have a forged crank, forged rods and 6 bolt main bearings from the factory.

The pistons are cast so that's really the achilles heal if you add too much power or boost on top of the factory 10.5:1 compression. Jubu claims that the pistons are susceptible to breakage when they've tested tunes that delivered in excess of 500NM of torque so it's interesting to hear Greg's experience. There are plenty of stories online about twin turbo 700-800 HP 2GR's with the stock block and crank but new forged rods and pistons so there's a ton of potential if you have the funds and that's how the Jubu short block comes for those that want to build the motor to that level.

I think the original poster has the right idea for his situation. If you have to pull and rebuild the heads anyway, why not exchange your cores for new heads that have been ported and built with a high performance valve train to support higher RPM's. Seems like a natural without breaking the bank.

 

[speropagos]

A lot of great info here, thank you! My intention to keep it as my daily and not to track it, so reliability is a top priority. With that said, if I go the happy medium route with upgraded heads, and a roughly 460-480HP tune and push to 7600 - 7800 rpm(more critical than HP), is this possible or do I need to also do the pistons and have the heads ported in this scenario? Is there anything else I should consider? TIA

 

[speropagos]

Save your money and just replace with stock parts or heads if there was that much damage which it doesnt sound like there was.
If you are trying to eek every bit of hp out of the car for track use then sure, do a long block or built internals but otherwise the factory long block will live at 500hp all day long providing its on a good tune.
The only internal engine change in my 520whp track car is cams, springs and retainers.

Thank you for the info. My objective is to maintain it as my daily, tune up to 500BHP (not over) and push the RPMs to 7600-7800, as long as I'm replacing valves, is there any benefit to doing a more performance based head swap?

 

[speropagos]

Here's a screenshot of the inside of one of the cylinders, thoughts?