Supercharger kit

[1979scotte]

@thetyrant please stop quoting bhp as a limit on a 1zz. Bhp doesn't brake engines torque and boost break engines. Keep torque below 240ftlb for SAFETY. That is considered safe for the gearbox.

@Snelbaard
TTE turbo is absolutely no good for the 2zz it's too small to do it justice its a tb2559 you want something much larger like a GT28**

The reason people slag off the 1zz for Fi is because you can't just boost it up to the eyeballs like a 3sgte its fine on a small gt25 turbo with 10psi and good cooling.
The 2zz has much stronger rods from factory and hold much more boost from much bigger turbos. Also because they have much less torque than bhp you can make over 300bhp on them and only 230 ftlb for example they work really well with rotrex.
As ever the key is the mapping and the amount of time (read money) you are willing to spend to get a great tune.

Thats my opinion anyway.

Indeed torque is the usual culprit for breaking rods especially, ive quoted power as its easier for people to relate to a lot of the time, also as a general rule on 4cylinder at least peak power is often a higher number than peak torque so if say working to 220 max whether its power or torque its safe limit,  but as you say many run more with gearbox being problem with higher torque as well as the rods.

I will try to remember and quote both in future to stop you moaning lol

220 is low whatever way you cut it unless it's at the wheels.
You may know what you're talking about and you may not but newbies read these threads and take it as gospel truth. Never hurts to have a debate.

[thetyrant]

Im talking about safe limits would you not agree 220 is just that ?  sure you can and many do run 240-250 but to me that is close to the limit of engine so to me its not what I would recommend as safe levels, i appreciate everyone has different ideas on what safe and im always on cautious side as ive learned the hard way in the past not to chase numbers .

I would never recommend higher hp/trq that im happy to run myself, also car usage plays a MASSIVE part in what the engine can handle, im sure at 240 car will take the occasional hard blast on road no problem but try and get it to hold together for 20mins flat out on track is a whole other ball game as im sure you know.

We need to remember this is high compression NA engine never designed to be boosted so its under massive stress even at 10psi of boost.

Out of interest how many cars do you know of running around the 240 longterm and running them hard on regular basis ?  always keen to know what people are doing and how things pan out longterm as you don't always get that information, often only how great car was at start when it was mapped  etc etc.

[shnazzle]

This was my problem with the SP240 setup. Faaarr too little cooling to support the 235-240hp at full chat for a prolonged time. 
Great fun for occasional blasts and even longer b-road blasts for an hour but that's still not track use is it?

I do reckon though that with very good cooling, oil cooler, bigger and better sump, bigger coolant radiator and good engine protection, the 1zz will hold 250 reliably.

[Petrus]

Great fun for occasional blasts and even longer b-road blasts for an hour but that's still not track use is it?

Indeed it is not. Not even near half the load.

[MattPerformance]

This was my problem with the SP240 setup. Faaarr too little cooling to support the 235-240hp at full chat for a prolonged time.
Great fun for occasional blasts and even longer b-road blasts for an hour but that's still not track use is it?

I do reckon though that with very good cooling, oil cooler, bigger and better sump, bigger coolant radiator and good engine protection, the 1zz will hold 250 reliably.

Evidence of this lack of cooling Patrick? I'm not sure in what context anyone could use a car on the public highway "at full chat for a prolonged time"...?
I have run the SP240 kit in all of its guises, and I NEVER had any issues with temperatures or reliability. I drove it very hard.  I would not recommend heavy track use (esp in track tyres and suspension) without an uprated sump and oil cooler but as a road car being used hard, it was never found wanting.
I agree it would benefit from all of the upgrades to introduce more headroom for extreme use but I do not accept that it is under engineered in the way you have implied.

One other little anecdote though: the TTE Turbo kit (180bhp, 220ftlb) upon which both SP240 kits were based, had to pass the Toyota Standard 100 hour test (full power, flat out, for 100 hrs straight).  Taking the set-up up to 250 obviously eats into that headroom but it certainly proves the base-line reliability of the set-up...

[shnazzle]

This was my problem with the SP240 setup. Faaarr too little cooling to support the 235-240hp at full chat for a prolonged time.
Great fun for occasional blasts and even longer b-road blasts for an hour but that's still not track use is it?

I do reckon though that with very good cooling, oil cooler, bigger and better sump, bigger coolant radiator and good engine protection, the 1zz will hold 250 reliably.

Evidence of this lack of cooling Patrick? I'm not sure in what context anyone could use a car on the public highway "at full chat for a prolonged time"...?
I have run the SP240 kit in all of its guises, and I NEVER had any issues with temperatures or reliability. I drove it very hard.  I would not recommend heavy track use (esp in track tyres and suspension) without an uprated sump and oil cooler but as a road car being used hard, it was never found wanting.
I agree it would benefit from all of the upgrades to introduce more headroom for extreme use but I do not accept that it is under engineered in the way you have implied.

One other little anecdote though: the TTE Turbo kit (180bhp, 220ftlb) upon which both SP240 kits were based, had to pass the Toyota Standard 100 hour test (full power, flat out, for 100 hrs straight).  Taking the set-up up to 250 obviously eats into that headroom but it certainly proves the base-line reliability of the set-up...

Saying the same thing Matt.

Full chat prolonged meant track, as per thetyrant's post.
Agree its absolutely peachy on the road. Although I did record intake temps of over 70 which I found a bit excessive but nothing the ecu couldn't compensate for.
And I'm sure we can agree that an extra few psi and 50-30hp definitely decreases reliability. But certainly not to any concern.
But, I do think the little  TTE intercooler on a hot day did the job "ok" but you'd do well uprating to water/air for some extra headroom.

Just to add, for extra clarity on my position; the SP240 kit is one of the best performance upgrades for the MR2. It takes the TTE and takes it up a notch while maintaining all the benefits of the stock car and little hit on reliability. The parts are some of the best manufacturing I've seen and the SP exhaust and cat pipe were even commented on as very very high standard at the exhaust place I went to with it.
You can't knock the SP240 for what it is and what it proposes to be.

[MattPerformance]

Ok, but the SP240 kit was never marketed as a track kit, only a road car kit that can be enjoyed on a track (like pretty much every other performance road car).
When the kit was being sold the concept of a "track car" barely existed!
If you want a full track kit then you need to dig a lot deeper, not just on the turbo side, for the whole car...

[shnazzle]

Ok, but the SP240 kit was never marketed as a track kit, only a road car kit that can be enjoyed on a track (like pretty much every other performance road car).
When the kit was being sold the concept of a "track car" barely existed!
If you want a full track kit then you need to dig a lot deeper, not just on the turbo side, for the whole car...

Absolutely. 

Hence "You can't knock the SP240 for what it is and what it proposes to be."

We tend to forget that track is a very harsh environment and a road car can't be expected to hold up under those conditions for a long time right? 

[MattPerformance]

We tend to forget that track is a very harsh environment and a road car can't be expected to hold up under those conditions for a long time right?

People that have never experienced proper track driving probably won't realise to what extent that statement is true.
I reckon track driving is on average 10 times harder on a car than road driving...

[Petrus]

We tend to forget that track is a very harsh environment and a road car can't be expected to hold up under those conditions for a long time right?

People that have never experienced proper track driving probably won't realise to what extent that statement is true.
I reckon track driving is on average 10 times harder on a car than road driving...

The two cannot be compared. Racing is you are trying to be close to either full throttle or hard braking. On the road you are ttrying to avoid an accident. And that is not eventaking speed limits into account: On the open road the max highway is (bar exceptions) 120 km/h!
On the mechanical side any comparison goes out of the window because there is no base line: Which track, which road circumstances, which driver and how nuttah is he.
Same thing whích components you look at. Over here in August thrashing the car down the Sierra Nevada towards on the south slopes is testing brakes as it is a constant sequence of hárd braking at relatively low speeds whereas on a race track the air gives the brakes a breather.
And thén there is city traffic on a hot day. Ambient air 45 degrees C., tarmac hot enough to go soggy, no cooling air from traveling speed... The car may not be pumping out max horse power but the horses sure get overheated. Ok, no thrown conrod but a blown head gasket perkaps. Hence the TTE fans in the engine lid; for the city crawling of all things.