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2GR supercharged? Anyone has done it?

I wonder how big you can go with being able to close de lid?
 

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It does not fit with the turbo lid and the stock rain shield.

More importantly, the supercharger really ruins the engine feel on this swap and does not add enough horsepower to make up for it. I strongly suggest you avoid that supercharger.
 

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More importantly, the supercharger really ruins the engine feel on this swap and does not add enough horsepower to make up for it. I strongly suggest you avoid that supercharger.
Interesting. I had previously thought that if my car's suspension and performance got to a certain point, that I would need the power of a supercharger (for example a harrop tvs1900) but now I think I'll stick with n/a.
It might be beneficial to keep the center of gravity a little lower as well. Thanks for the advice mark.
 

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Harrop has recently made the TVS 1900 with integrated A2W intercooler available for direct purchase. My feeling is this is a superior alternative to the TVS 1320 but I don't know about fitment under a SW20 deck lid and I certainly don't know about the drivability/feel.

Product link:
https://www.harrop.com.au/shop/automotive-performance/superchargers/harrop-tvs2300/tvs1900-toyota-2gr-fe-v6

Note the price tag $9,200 is listed in AUD which converts roughly to $6,500 USD.



PS. Evident from this promotional video that this would require an F40-type lid.


PPS. Looking carefully at various points of this video, it appears that the upper pulley bracket utilizes the same mounting points are our SW20/2GR swap motor mount so fitting this in our cars is not straightforward.

Belt Routing:


Idler Bracket:


The illustration shows the TVS1900 non-intercooled but afaict it utilizes the same idler bracket as the TVS1900 with intercooler.

Source:
http://www.simplysportscars.com/shop/img/cms/INSTALL GUIDES/171 T3EX 02 A - SC KIT, V6, NON IC - Install Guide.pdf

PPS. For anyone wondering, the price tag for this lovely piece of engineering (the idler bracket) is $1,783 USD plus shipping. Really you don't have to look more than five minutes to see that everything that Marc ever made and sold is a complete and total bargain.

https://www.lotuspartsonline.com/a/Lotus_2015_Evora/62888412__6703260/Auxiliary-Drive-Belts--Pulleys/EA4103.html

As an alternative I can see using a lower pulley kit (like the one sold by Marc or HKS) and fabricate a mounting plate for the two upper pulleys. This should come out quite a bit less in cost and allow mounting the engine with a SW20 swap mount.
 

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The newer setup with the intercooler may address the issues i had with it. Overall the motor just lost all of it's rev-happy nature. The NA version of this motor revs from idle to 7200RPM in less than a second. With the supercharger on it it's just so damn sluggish under 3000RPM, idle to redline takes a few seconds to get to 3000 then it starts building revs much quicker but still not quickly.

I spent a few minutes making a composite of the TVS1320 tune with the current MAF tune i sell and it somewhat explains the situation. Keep in mind it takes 58% more air (8.5psi) to get that 16% power gain. There's a lot of heat in this equation and it shows in the timing, the motor has to run about 18 degrees less timing with the supercharger on it.


Note that while it does make more power, the supercharger does add quite a bit of rotational mass to the engine.
 

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The newer setup with the intercooler may address the issues i had with it. Overall the motor just lost all of it's rev-happy nature. The NA version of this motor revs from idle to 7200RPM in less than a second. With the supercharger on it it's just so damn sluggish under 3000RPM, idle to redline takes a few seconds to get to 3000 then it starts building revs much quicker but still not quickly.

I spent a few minutes making a composite of the TVS1320 tune with the current MAF tune i sell and it somewhat explains the situation. Keep in mind it takes 58% more air (8.5psi) to get that 16% power gain. There's a lot of heat in this equation and it shows in the timing, the motor has to run about 18 degrees less timing with the supercharger on it.


Note that while it does make more power, the supercharger does add quite a bit of rotational mass to the engine.
Seems like a lot to deal with for a 38hp gain. Steven Godfrey has a naturally aspirated 2gr making 400whp.
Of course it's fully built, tuned and has itb, but I still feel that building an n/a is the way to go for me.
 

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Seems like a lot to deal with for a 38hp gain. Steven Godfrey has a naturally aspirated 2gr making 400whp.
Of course it's fully built, tuned and has itb, but I still feel that building an n/a is the way to go for me.
It's actually a 48whp gain, not 38hp but the gain is only realized at the very top. But also realize that Dave Staba at DDPR claims he can get another 20hp from this motor with a nicer exhaust and an aftermarket ECU. Between that and some porting and camshafts it's not hard to see how you could easily have an NA motor making more than the supercharger setup does. 400whp of course is a whole other ball game, I'd love to see the build sheet on that and i bet that thing is a damn riot to drive.

Plus what this picture does not show is how much it just kills the joy of driving this motor in NA trim. There's a reason that despite all the effort i put into the belt routing system for this setup that I dropped the project before full production.



Secondary to all this was the ECU. At the time i was unable to change the injector sizing on the 2GR ECUs so i was forced to use the TRD ECU. This means i had to use an immobilizer or work at it for 100-300hours to figure out how to eliminate it on this ECU. Since then I'm getting really really close to being able to change injector size on the ECUs so that part of the problem has gone away. I will not be picking this supercharger setup back up, the newer intercooled ones would likely be much nicer, most of that timing would probably be able to go back in but the supercharger is just too expensive to build a kit around it.
 

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This simulation is based on actual time slips for a cammed NA 2GR (mine) and a TRD Supercharged 2GR (Eric's). Of course there's more that goes into a 1/4 mile time than peak HP, there's weight, gearing, shifting, tires, torque, and so on.

 

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Interesting!

What about a Rotrex supercharger?
Using a rotrex on this motor would mean you get to keep the stock intake manifold setup which helps this motor build low end torque. I do think it would be a reasonably nice setup but the downside is there's no good spot to mount it so it ends up being a pretty complicated setup to use on this motor in order to fit in the stock engine bay.

I made a bit of progress on this using a jackshaft setup to mount it on the back side of the motor and it all fits in the engine bay this way but i could not get the cost down enough for the 5-10 sales that would have resulted. (ignore the white powder, i was 3d scanning stuff)
 

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What about a Rotrex supercharger?
I did previously build a Rotrex 1zz and was very happy with its performance so this motivated me into following Marc's lead to investigate the application for the 2GR. I've been toying around with some ideas and you can find some info on what I've done here:

https://www.mr2oc.com/188-v6-mr2-forum/671953-2gr-fe-rotrex-supercharger-sizing-3-5-liter-v6.html

https://www.mr2oc.com/188-v6-mr2-forum/676746-rotrex-supercharger-2gr-fe-3-5-liter-v6.html

This project is stalled right now because of lack of time.

Some other Rotrex tid-bits:

There's a guy in Poland with a Rotrex 2GR (search Rotrex on this forum) but very little available info.

Another guy who I'm guessing is in either Singapore or Hong-Kong posted limited info on his 2GR-FE Rotrex build is in the Australian Mr2 group forum - he used a jackshaft adapted from a scion tC TRD supercharger.
https://au.toyotaownersclub.com/forums/topic/52317-toyota-aurion-with-rotrex-supercharger-trd-rod/?tab=comments#comment-554744

There's a guy named Patrick Chambers in UK whose name comes up sometimes in association with 2GR-FE Rotrex builds but I haven't been able to find any info about his work other than passing mentions on Facebook.

You can Google "Rotrex 2GR-FE" and it will come up with a few other hits but nothing really meaningful.


The video mentions 300rwhp. is that what the TRD ECU dynos at without my tune tweaks?
Eric mentioned this number and I recall there was some discussion at the time on whether Australian dynos read low or US dynos read high or whatever but I don't recall the details of the tune or setup that he used. It was from a couple of years ago when you got the TRD SC stuff going. Anyway I was surprised that my time slip was faster than his time slip maybe it's not just the dynos that read differently in Oz.

With the supercharger on it it's just so damn sluggish under 3000RPM, idle to redline takes a few seconds to get to 3000 then it starts building revs much quicker but still not quickly.
Wow I had no idea. This sounds like bogging pure and simple. No way to fix this in the tune?

Note that while it does make more power, the supercharger does add quite a bit of rotational mass to the engine.
Thinking about how much power gain is possible with a supercharger on a stock 2GR-FE engine... I'm assuming 500bhp as the safe mechanical limit for the motor before something breaks. At that point I'm guessing 10-15% goes to drive the SC and then another 10-15% for drivetrain so the setup is limited to 400whp if not less. Interestingly Harrop also suggests building the motor to go above that with the TVS1900.
 

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Wow I had no idea. This sounds like bogging pure and simple. No way to fix this in the tune?
I'm not going to say more tuning could not fix some of this, i did not spend months on this like i did with the 290rwhp NA tune but i do think a big part of the issue is just that the low end torque is killed with the intake manifold and the supercharger heat means i have to pull timing which kills even more torque. Add to that the 10%+ that gets eaten up by the supercharger drive and there's just not enough low end torque available to keep it snappy. I think an intercooled setup would be a really big step forward along with a tune that is more aggressive on the timing. Alternately with the stock Aurion supercharger and an aftermarket ECU setup with E85 would also make up for the lack of an intercooler.


Thinking about how much power gain is possible with a supercharger on a stock 2GR-FE engine... I'm assuming 500bhp as the safe mechanical limit for the motor before something breaks. At that point I'm guessing 10-15% goes to drive the SC and then another 10-15% for drivetrain so the setup is limited to 400whp if not less. Interestingly Harrop also suggests building the motor to go above that with the TVS1900.
I don't have enough experience to speak to these numbers but they do seem conservative. The TVS1320 is a very capable supercharger and the pressure ratios we're talking about here don't have the supercharger in the high efficiency island anyways, adding more RPMs isn't really reducing the efficiency by any large amount.
 

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Does a Rotrex supercharger would fit replacing the A/C compressor?
There are two issues (at least) with putting the Rotrex in the AC location: one is the intake for the compressor would interfere with the exhaust. The second is the outlet would run into either the alternator or the firewall depending on how you clock it. You could relocate the alternator and maybe modify the exhaust somehow (I don't know how). This is not a good location.

Next question: would it fit in the power steering location. No, not enough room and same issue with the exhaust and intake interference. But if you're clever you can put a pulley in the power steering location and run a jackshaft under the rear bank header with the supercharger mounted on the transmission side below the throttle body. It could be mounted with a bracket using the differential cover plate bolts. This could be a pretty good spot for it.
 

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Yeah, it'll fit where the A/C compressor goes but the plumbing would be very difficult. This old picture shows this a bit, you end up with intake air right next to the header and the pressurized air needs to go where the alternator is or it needs to eat up all the ground clearance available.

If i was going to do yet another attempt at mounting a rotrex on this motor I would mount it backwards and use a double sided serpentine belt and drive it from the backside of the belt. This would place the intake air right in the path of the right side air intake and provide a good path for the pressurized air to go up and over.

The bracketry would be complicated but it would avoid a jackshaft and stupid intake plumbing. but it certainly would still not be simple by any means. The easiest way may actually be a custom alternator case now that i have capabilities to get castings made.
 

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The newer setup with the intercooler may address the issues i had with it.
Here's a dyno of the Harrop TVS1900 supercharger with intercooler, done by BOE.



Response looks pretty good on video.


Of course BOE hypes the living heck out of it. See for yourselves.

https://www.boefab.com/products/evora-chargecooler-series

PS. I want to note here that I approve of their setup of the swirl tank/fill tank as the high point of the IC system. I use a very similar tank setup in my W30. It might even be the same tank, minus powdercoating.
https://www.amazon.com/gp/product/B003BZX4WW/
 
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