Gen3 Debate

[MR2T32]

i don't think anyone here is saying that gen1/2 is better than gen3. But when it comes down to it, is it really worth paying that much more for a gen3? IMO it's about the money. I paid 2800 for my gen1 swap compared to 5500 for a gen3 swap. That's 2700 difference which is almost the cost of my swap. I could easily get a Street Brawler or some other turbo w/ other mods, and i'll end up paying about the same price for a gen3 except i'll have a better or comparable turbo and be faster.

[GReddySetGO]

I guess its a little diffrent for me cuz I didn't pay for any labor, just the clip itself. But like I said, if I ever had to do it all over again, the Gen3 would be my first choice, right off the bat.

[keithlee21]

It seems to me that everyone seems to think the Gen3 difference comes down to money. Let's face it! Yes, it is more expensive. But, lets also realize there are many differences between the generations:

Gen III Differences
- MAP sensor instead of AFM
- Bosch D-Jetronic (Gen III) vs. L-Jetronic (relatively primitive) engine management
- CT20b turbo replaces CT26
- Boost raised from 10psi to 13psi
- Fuel cut raised from 12 psi to 18 psi
- Different ECU
- 4 wire O2 sensor
- Shim under bucket valve shims
- slightly more aggressive cams
- Revised internals (pistons, con-rods etc.)
- Revised cylinder head cooling passages/water jackets
- Revised intake manifold (8 'independent long ports' reduced to 4)
- intake manifold inlet air temperature sensor added. i.e. after turbo and intercooler.
- Revised gearbox with close ratio gearing
- lower compression ratio
- stainless steel head gasket
- factory 540cc injectors replace 430cc injectors
- revised fuel rail with bigger bore and relocated pressure regulator
- TVIS eliminated
- EGR eliminated
- LSD in 80% of them
- throttle body increased from 55mm to 60mm
- inlet valve lift increased from 8.2 to 8.7
- intake manifold inlet air temperature sensor added
- Less restrictive exhaust elbow
- Aluminum oil pan
- more rigid alloy sump and additional oil baffles
- Factory Catch can
- Better Oil Cooler and relocated oil filter (bottom)
- 4 Channel ABS coupled with Traction Control available
- No. 1 compression ring described as 'stainless steel' instead of just 'steel'. Oil ring is described as 'stainless steel' instead of 'a combination of steel and stainless steel'.
- The fuel pressure raised from 36 PSI (2.55 bar) to 41 PSI (2.9bar).

If you notice many of these changes are being made by owners to their USDM engines. I see many owners putting on aftermarket boost controllers, putting on different intake manifolds, boring out their throttle bodies, etc...But, I am a huge believer in stock Toyota OEM quality and, I like the fitment and quality of a stock part rather than an aftermarket one.

But, as for money being the main subject for debate. If you can afford it then you have the option. We all know that it is very possible to make your car more powerful, cheaper with the USDM engine. But, would you also say that the Gen3 has the same or more capabilities to make power as the USDM engine? If you want the cheapest way to make power then I would suggest to stay with the USDM engine. But, if you are investing into your vehicle for the long run then I would suggest to keep the Gen3 in mind as an option for powerplant to go with.

But, most of all...regardless, of which engine you decide on please DO NOT NEGLECT TUNING!

[Nacho]

Originally Posted by GReddySetGO

Gen3 head > Gen2

I agree with 47MR2's on this. Most people who are trying to say Gen1/2 is better, or just as good etc. Have never had a Gen3. I've had both, and so have many other people. Ask anyone whos had both, and they will tell you Gen3 is the way to go.

Not the people who can say Gen1/2 is better, but have never owned a Gen3. They've only read about it, or "I've sat in a Gen3 before" type of situation. Take it from those who have had both, like me. Gen3 is the way to go.

My co-driver has a ~400 WHP gen II and he loves my engine more than his own :x

[Nacho]

Originally Posted by MR2T32

i don't think anyone here is saying that gen1/2 is better than gen3. But when it comes down to it, is it really worth paying that much more for a gen3? IMO it's about the money. I paid 2800 for my gen1 swap compared to 5500 for a gen3 swap. That's 2700 difference which is almost the cost of my swap. I could easily get a Street Brawler or some other turbo w/ other mods, and i'll end up paying about the same price for a gen3 except i'll have a better or comparable turbo and be faster.

You're comparing powerband and overall quality of the motor aas well as potential to raw numbers. Yes, you can get as much, if nto more power on a gen II for the same cost. However, your powerband will be worse due to poor head design and weak cams. You'll be MAF limited (as opposed to MAP limited). You'll HAVE to get a new turbo to make the same power as the ct20b.

will you be faster in a straight line? Yes, probably. Will you have as streetable a car and the spool of the gen III, not to mention have a powerband that's actually good to redline? Nope. So figure out what's important to you and go from there.

[MR2T32]

well said kblake, and I agree completely about the comment about knowing what the personal goal is.

[Nacho]

Originally Posted by kblake

IMHO:

Gen 3 > Gen 2 under these conditions:

Stock vs. Stock
BPU vs. BPU

As soon as you take the head off the engine, and start doing cams, porting, forged pistons, ems etc. they become equal, or the gen 2 has a slight edge, due to better parts supply chain in North America. Then there is the fact that a ported gen 2 head can ultimately flow more than a ported gen 3 head, with it's smaller ports, which are a compromise between low end and peak power.

What about the fact that the gen 3 head can support more aggressive cams than the gen 2 due to the latter's larger casting for the buckets. All agressive japanese spec cams are made for the gen 3, not the gen 2.

Or the fact that the gen IIs actually suffer from port jobs? the valve-port ratio is already poor, and the best thing to do is put in LARGER valves. Also shim under bucket > shim OVER bucket.

The gen 2 head is inferior, no matter how you look at it. Let alone the intake manifold, turbo, MAF (vs MAP), etc.

[Nacho]

Originally Posted by kblake

First off, the gen 2 head is easily modified to accept the high lift cams you are referring to. Secondly, I only know of less than 10 people in North America with setups that might require a high lift cam, vs. a standard 272/272 or the increasingly popular 272/264 staggered cam setup.

Good story. Big cams still don't fit without mdification to the casting.

With it's larger ports, using 1mm oversized valves, the ratio is actually better than a gen 3, and the head will flow more CFM than a gen 3 with the same port job. Chris K. has built some of the most powerful 3SGTE's on the continent, and he prefers the Gen 2 head. He's posted flow bench results comparing both heads, and proving the ported Gen 2 flows more. That's good enough for me.

Yes. Toyota went backwards in their design, and has based their most successful race 3S cars in JGTC and WRC on a poorer head design. It makes perfect sense. Why put R&D into making it better when we can make it worse?

More isn't always better. With honda cars, the B18C1 head flows MORE, but the B16/B18C5 head flows better. The latter makes more power. IBhonduhsDontMatter

If you are doing cams, you should be doing a shimless bucket conversion at the same time, and shimless > shim under bucket.

Shim under bucket won't puke the shims out, so there's much less reason to convert. You still can, if you want to toss money away.

That's all stuff that gets thrown in the trash once you go past bolt-ons. It's the stuff that you pay extra to get with the Gen 3, and then you wind up having to replace it anyway, once you go for serious power. I don't know about you, but I hate buying the same part twice because I didn't plan well in advance.

Ken

Likewise, why not spend the extra up front and not have to spend MORE replacing inferior parts? riddleMR2 made 312 on his t3/t4 MR2 on the stock gen 3 ECU and an FPR. He made 316 on the Blitz ECU after it was tuned. Seems like the stock ECU is pretty capable. And without the huge restriction of the MAF, there's even less reason to swap it out.

Unlike the gen 2 part, the gen 3 intake manifold isn't a huge restriction, nor does it cause failure with the cyliners going lean.

I agree that if you want to get crazy nasty with the car and make it a 2.3L beast or something of the like, might as well start with the gen II for less cost. However, if you're not planning on basically reworking the entire thing, the gen 3 is a better choice. Hell, the closer ratio transmission w/LSD alone is usually the price difference.

[DavidV]

Originally Posted by kblake

Chris K. has built some of the most powerful 3SGTE's on the continent, and he prefers the Gen 2 head. He's posted flow bench results comparing both heads, and proving the ported Gen 2 flows more. That's good enough for me.

Has anyone called JUN, Phoenix's Power, Tom's, or any of the other backyard tuners in HyperRev to let them know? Man, the guys in Japan are going to be caught off gaurd by ChrisK's findings.

That's all stuff that gets thrown in the trash once you go past bolt-ons.

Yeah. When I first got my clip I was like: "WTF is this MAP Sensor doing here!? Someone get me an Air Flow Meter, pronto! Hey, is that a large plenum I see on the intake manifold? Yuk. Throw that thing away. Where the hell is the cold start injector? Don't tell me I need to buy one... ugh... and that oil filter on the bottom is so strange. Can someone move it to the middle of the engine compartment?"

-- DavidV

[Nacho]

Originally Posted by kblake

Japanese drivers and tuners are a completely different demographic than U.S. drivers. Why do you think the North American market MKII naturally aspirated got a 2.2L economy sedan engine, good for nothing but it's low end grunt, while every other market got the free revving naturally aspirated variant of the turbo motor? (3SGE) Most Americans are not willing to wait until 5k RPM for their turbo to spool. Most would not be very happy with a car put together by any of the tuners you list above.

NO ONE wants a turbo that spools at 5k unless they're a drag racer only. Which, BTW, is quite an american past time. Much more so than anywhere else in the world

[Ncturnal]

There's nothing like a good debate. Both sides have merit that everyone can benifit from. Ultimately, the choice is up to the buyer, and as a buyer, I've always appreciated hearing good debates on any purchasing decision I was about to make. Thanks for everyone's informative input.

[Nacho]

Originally Posted by kblake

I wouldn't be using what Toyota has done as an example. If you do that, we'll all be driving front wheel drive sedans and econoboxes. The cars you are referring to had to be based on a factory powerplant. They weren't doing the same kinds of mods that people are doing to the engines. If they were after the kind of power some people are looking for these days, they simply broke out the 503e.

You honestly think that the racing division had no say in the revisions of the engine? By making the production engines better, they're only saving themselves work in changing it to a race engine.

I'm aware of that. Velocity is important as well, and is one of the things Chris designs for when porting. You ARE aware that he builds race motors for a team down in Australia/NZ?

Nope, wasn't aware.

You're right, unless you want to have a competition for who can transport the most groceries, honDUHS DON'T matter, for the purpose of this discussion.

Yes, Honda as a whole is totally unsuccessful at racing, as well as engine designing. How'd Toyota fare in F1 last year again?

I'm well aware of that. Shim under bucket was what people USED to do to their gen 2 heads, before the shimless bucket conversion was available. You would know this, but you either didn't have your driver's license yet back then, or you were still playing around with honDUHS. Do you have an MR2 YET , or are you still posting based on other people's cars?

I've had an MR2 for over 2 years now, been racing Toyotas for 2 as well. I've been modding and racing Hondas for the 3 years previous to that. Does my broader knowledge base regarding cars than yours somehow detract from my credibility?

And may I ask, how much time have you spent at actual race tracks? You know, ones that don't go straight. Since you seem to have this massive bias against Hondas and feel they're inferior, I wonder if you know about the wealth of real-world, race tested knoweldge their community has aquired over the years. I welcome you to check out the road race/autoX section of Honda Tech some time.

Anybody can make big power once or twice. It doesn't prove a thing. Making it reliably, day in and day out is another thing entirely. One advantage of the AFM is that it adjusts automatically for changes in Ve, as long as you stay within it's range of measurement. Speed/Density is much more sensitive to changes in Ve, and should be retuned with any major changes. Oh wait, there's no way to retune the stock Gen 3 ecu... never mind.

The problem with AFMs is that with big power, they tend to max out early in the game. And once they hit 100% deflection, they're useless. MAPs are a much more versatile system, as well as being less restrictive.

And my point about the stock gen 3 ECU making 312 vs the Blitz tuned ECU making 316 is that the stock gen 3 ECU is quite capable in it's own right.

As for ECU reflash's, off the shelf reflashes I'm not a fan of because they're not configured for a specific set of car/mods/elevaiton/etc. and custom reflashes are getting to the point where a programmable ECU is becoming a more and more attractive option.

The gen 3 tranny is no different than a 93+ gen 2 transmission with LSD. The tranny my car CAME with.

My RPMs are awful high on the highway at normal crusing speed. Higher than my co-driver remembers them being when he had the car (it was originally a 93T w/ the LSD transmission). I know they're higher than my 91 was.

[Nacho]

Originally Posted by kblake

What racing division ran the 3SGTE?

JGTC Supras ran engines based off the 3SGTE, as well as the WRC AWD Celicas. The ST205 Celicas did quite well in the old Group B rally category, where you had to keep the engine work pretty close to stock.

We're not talking about those cars. Honda has a long history of building nice race cars to compete with, and giving the masses wrong-wheel drive grocery getters to drive around in. In any case, I can't for the life of me see how Hondas are germane to a thread about two different flavors of an engine in a mid engine, RWD TOYOTAsports car. There's only one Honda that fits the bill, the NSX, and it still has nothing to do with the Toyota 3SGTE. I don't have anything against Hondas in general, one of my vehicles is a 2003 MDX. My objection is when you take an economy sedan and try to turn it into a sports car. There's a reason why the first big power increase for a Civic requires an ENGINE swap. It's because Honda didn't make them to go fast, they built them to transport people to and from the grocery store. My 57 year old mother drives a 91 Civic. She recently relocated from Boston to San Jose. I had to explain why kids were pulling up to her at lights and revving their engines at her.

Physics are physics.

And your random ranting about how worthless they are is inly wasting your breath. They're still racing, and winning, and you're still here talking about racing.

Only when you try to use it in a discussion where it has no bearing. News Flash: My MR2 is one of 3 cars I presently own. I've owned and worked on a lot of other cars in the past. I just don't bring them up on the MR2 FORUMS because they are not MR2's There's a perfect forum for you to talk about Hondas though: http://www.mr2forums.net/forums/forumdisplay.php?f=33

The fact that the MR2 communiy as a whole seemingly doesn't want to accept known facts and apply them to our cars is why there's been 2+ 7 page threads discussing 2.5" pipe vs 3" pipe. 3" is better. Period. Done.

If you try to operate in a vacum of the knowlegde gained from others, you're going to be inefficent.

I've attended two hot lapping days at Portland International Raceway, one at TGPR (SE2001), and one at LVMS (SW2003). I actually prefer driving my car on a road course to taking it to the drag strip.

I'll take my 5 seasons of racing and not talk about what i know anymore.

I'll check it out right after I buy a Honda that I plan to road race/AutoX.

There's MANY other types of cars owned by people on there, and they're all discussed. Unlike some forums, the people who started there are welcome back with their new cars.

The 3SGTE AFM doesn't reach full deflection until somewhere around 300RWHP. Someone recently measured the pressure drop across the AFM at that volume of airflow, and the restriction was negligible.

Ok. The AFM is still inferior to a MAP as it becomes useless quite early in the 'huge power' department you're talking about.

MY point is that speed density systems are very intolerant of Ve improvements. Those cars may make that power short term, but in the long run, they will probably blow up if the ECU is not retuned.

IIRC, RiddleMR2 ran on his for over a year. But I'm sure it was JUST about to blow up.

ATS has a dyno, and offers tailored reflashes. We also have an extensive bank of maps for various setups, that we can ship out mail order. Those will obviously not get everything out of a particular setup that it's capable of, (because we are fairly conservative with the mail order tunes) but they are better than the generic ROM tunes that G-Force Engineering and Toyomoto were selling in GB's of the past.
I always recommend an EMS over a ROM tune, but sometimes it's just not in the budget. That's happening more and more, as the price of the car comes down to the point where just about anyone can afford to buy one. Someone who pays $20k for a car, probably has a couple of grand to put into it in mods. Someone who spends $5000 for a car, probably has a couple of hundred dollars to put into it.

I was wondering when you'd turn this 'techincal discussion' into an advertisement. I find it odd that no matter what, you always use your 'techincal knowledge' to advocate your products. It's like you're a parts salesman or something.

That's what's known in scientific testing circles as "anecdotal evidence", and is not worth the time it takes to type it. Furthermore, you are comparing to your 91. My contention is that the 93+ Gen 2 has the same close ratio gearbox with improved synchros, and available LSD as the 93+ Gen 3. Here is some REAL evidence:

If i had a 93 car with a stock transmission to compare it to, I would. But the only local 93+ car that i know of is the one I own and the transmission in it is the one that was hanging off the side of the engine in the clip. The original transmission is halfway around the country last i heard.

I'd be happy to match RPM/MPH in my car vs one in a stock 93+ USDM tranny'd car.

91 sales brochure: http://www.koracing.net/img/91OptionsPage1.jpg

"5 Speed manual overdrive transmission"

93 sales brochure: http://www.koracing.net/img/93OptionsPage1.jpg

"5 Speed manual overdrive transmission with dual cone synchros"

and 3 lines farther down:

"Viscous coupling limited slip differential"

Ken

I'm not debating the LSD in the 93+ vs the non-LSD tranny in the early cars. Im debating the gear ratios. LSDs don't affect the gear ratios.

Additionally just because the synchro count and the fact they have an LSD doesn't neccessarily make the transmissions indentical.

Often times the Japanese equvilent of a car will have a shorter final drive as the speeds and distances traveled in Japan isn't as much as in America, taking away much of the neccesity to have a long crusing gear for MPG purposes.

[EL PAALO]

Thanks for all the info, guys. It's good reading.

[Nacho]

Originally Posted by kblake

You are proving my point for me. I said that if you are going to keep the engine pretty close to stock, then go for the Gen 3. I don't deny it's a great engine, especially stock, and with bolt-ons. It's just not better than the Gen 2, once you replace the intake manifold and stock ECU/sensors.

Read my lips: I don't care. This discussion has nothing to do with Hondas, and nothing to do with racing. It's about which flavor of the 3SGTE is better, for which applications.

Making more power isn't for racing?

If you try to take information from economy cars, and apply it to sports cars, you are going to waste a lot of time and money. Are you planning to put a girdle on your 3SGTE? No? Why not? Hondas do it when they go forced induction.

All the DOHC VTEC motors come with girdles stock. No need to add one.

And there's a difference between the structural rigidity of one engine and what you can do to make that specific engine stronger and the way air moves in and out of a head. Again, pystics are physics. Air doesn't care who manufactures the engine.

300RWHP. You are showing me examples of Gen 3's making a ****ping 16 more RWHP than that. The gen 3 has the same fuel pump, with the same limitations, despite the larger injectors. Either engine is running on the edge of safety above 275RWHP.

If the gains of the stock ECU vs a tuned ECU are 4 HP at the 300 WHP level, what makes you think they'll just significantly at higher levels? No one's really tested the limits of the stock gen 3 ecu that i know of.

And you can swap out fuel pumps for alot less than you can swap ecus. I don't see what the fuel pump limitations have to do with the ECU's allegeded inferiority.

Ahh, more anecdotal evidence. You're great at spouting hearsay, but a little short on facts.

That's not antedocal evidence, that's facts. gen 3. Stock ECU. 8+ months.
It made over 300 WHP. It made it for quite a while. At least 8 months. I don't feel like calling him solely to ask exactly how long his stock ECU was on the car before he got the Blitz. If i call him or talk to him online soon, i'll try to remember to ask if he remembers exactly how long.

Either way, you claim that the stock gen 3 ECU can't make power for long. I'd count 8+ months as a long time, not 'once or twice'

Oh please. There's no advertisement there. I was simply using ATS as an example to refute your argument. As I said in my original post, I always recommend a standalone, when it's in the budget. Sometimes it's not, and in that case, a ROM tune is better than relying on the stock computer.

You're using the products that you sell as a reason that the gen II ECU is better (even claiming that the AFM is better, which is a joke), just like you used to claim that a 2.5" DP was better than a 3' DP when you sold them for KO. Your 'tech' seems to mirror whoever you work for at the time's products.

I'll take a stock gen 3 ECU and it's MAP over a reflashed gen 2 ECU w/ AFM any day.

from: http://www.megaboost.co.uk/mr2/frames/techinfopage.htm

"Toyota MR2 - MKII Turbo (1989 - 1994)


Transmission: 5-speed manual, double-overdrive
Gear Ratios:
5th: 3.23:1
4th: 1.91:1
3rd: 1.32:1
2nd: 0.92:1
1st: 0.73:1
Final Drive Ratio: 4.29:1"

I wasn't able to track down anywhere that listed gear ratios for the Gen 3. Perhaps one of our Gen 3 owners will have the information.

In that case, i can find any gen II owner and compare them. I'll make sure to use the 15" rears and 225/50/15 tires as well so as to eliminate the gearing differences from different sized wheels.

[DavidV]

All I know is if I were anything but completely desititute, my engine choices in an MR2 would look something like this (and I would advise most people with reasonable financial means to look at them in this order):

(1) Gen III -- the ultimate 3SGTE for the MR2 (A fully up-to-date engine capable of hanging with the Evos and STis of the world with very minor tweaks. Unless you're poor, look no further).

(2) V6 SC - Brad Bedell showed the world what this could do. Great power with a nice, fresh and plentiful power plant.

(3) V6 NA - As simple and reliable to run as the 5SFE, only with some real grunt.

(4) Gen II - Kind of an also-ran in the higher HP MR2 engines. State-of-the-art in its day. Know and trust your engine builder, because this will likely have been torn apart and put back together at some point in its life or will soon need it.

-- DavidV

[DavidV]

Originally Posted by kblake

Most of the high HP MR2's in North America are running on some built version of the Gen 2 at the moment.

Here's my built Gen 2 vs. a certain Gen 3. The Gen 3 is running 18psi to my 17psi of boost:

Ken

That's cool. I've seen that chart before. It doesn't change my rankings or opinion. Gen II was nice back when it was the only game in town. Fortunately, there are some newer and more interesting options available for those of us with an aversion towards "built" motors.

-- DavidV

[AndrewMcG]

So Ken, it's obvious that your motor is superior to this "certain" persons Gen3 but doesnt this prove David's point? Your motor has been built and rebuilt how many times? Both mine and David's motors are unopened and putting out similar numbers. Fair enough, we have more lag.

[DavidV]

Originally Posted by kblake

Actually, that's the first time I've overlaid my ChrisK motor with your plot. The one you saw before was Kris Osheim's stock Ve Gen 2 overlaid on your Gen 3

Kris didn't have cams, or an extrude honed stock intake manifold, so you eventually caught him on the top end, unlike me. That overlay is not as clear a victory for the Gen 2 as mine is, but it provides a better picture of stock gen 2 against stock gen 3, with only bolt-on power adders.

Then this chart is mislabeled, apparently.

The dyno plot on my car is an Apexi turbo kit, not Blitz.

Also, both plots seem to indicate that my set-up is holding better power on the top-end. This is why it is frustrating for me to keep looking at these comparisons.

The plot you have from me was a very conservative tune designed to carry the car through a grueling Time Attack competition. The tune itself was on 91 octane on an unopened motor. Hell, the fact that you could compete in a Time Attack shoot out with a stock, unopened motor says something about the Gen III in my book (and let's put aside the wastegate failure I had there -- during warm up, we were at least on par with the WORKS Evo and passing the Power Enterprise Supra). As a matter of fact, wasn't Brad's USCC motor also completely stock internally?

Anyway, the point is, it comes as no surprise that my car does not have the area-under-the-curve of the two you are comparing against, and that has next to nothing to do with the fact that it is a Gen III and everything to do with having a large Apexi turbo that is just coming into its power range at 17-18 psi. I would guess that the sweet spot on that turbo is 22-25 psi.

I have little doubt that with a stiffer wastegate spring, a set of cams, and some race gas, my current set-up could support 400+ whp. But then, I kind of have this general distaste for bench racing and have no such mega-power aspirations at present, so for now, let's leave it at that.

-- DavidV

[DavidV]

Originally Posted by kblake

We all know that what wins a race is more "the nut behind the wheel" than which car has more power. If you were beating those other cars, it is likely that it's because you are a better driver than the guys driving those other cars.

Yeah... only I wasn't the one doing the driving.

I can thank Hayashi for that. No way was I qualified to run against the likes of Tarzan.

Anyway, the front straight times was what I was going by, and I think there is a lot less driver skill there than other parts of the course (safe assumption being most everyone is mashing the throttle to the floor at that point).

-- DavidV