Gt4 St205 Threshholds Of Power

[Dominos Rox!]

Hi guys

how you guys doin, im new here

I have a gt4 celica 205, 206kw At the wheels (276 bhp at the wheels)

i am wondering,

what is the maximum power that a gt4 205 can take in stock internals?

[Sketchy]

Hi guys

how you guys doin, im new here

I have a gt4 celica 205, 206kw At the wheels (276 bhp at the wheels)

i am wondering,

what is the maximum power that a gt4 205 can take in stock internals?

How Brave are you.....

There's a few guys running 450BHP on the stock internals.

However normally it's recommended you look at forged pistons above 350, and con rods if you going much above 400. Stock bottom end is pretty strong and should be ok up to 450-500ish....

The stock pistons are very hard, however they are also very fragile, they can take a lot of boost and heat but are distroyed by a very small amount of det. So in the end it will all come down to how you get the car mapped and how far you push you mods.

If you looking for every last bhp out of your setup you will be right on the edge of the det threshold in which case I would highly recommend a forged rebuild to provide some longetivity.

However if you mod the car to be capable of a lot more than what it ends up running then the map will be alot safer and you'll be able to run stock internals for longer...

[Dominos Rox!]

ok

suffice to say, 350 bhp is really a good area to consider a rebuild forged.

also

when you speak of bhp and kw, you mean at the wheels or engine?

jsut so we are at the same ball park here

ok so also correct me if im wrong:

The stock internals should be ok up to 400 providing i take good care of preventing detonation and stuff like that

is that correct?

so putting measures to stop det such as

1) FMIC or uprated IC

2) Water injection Maybe?

3) Fuel additives such as fuel star units

4) computer tuning for more fuel to safe margin the det potential

is this correct?

so the stock internals and stuff should last

how bout the gear box, torsen?? how much can they withstand?

also the standard clutch?

[Sketchy]

ok

suffice to say, 350 bhp is really a good area to consider a rebuild forged.

also

when you speak of bhp and kw, you mean at the wheels or engine?

jsut so we are at the same ball park here

ok so also correct me if im wrong:

The stock internals should be ok up to 400 providing i take good care of preventing detonation and stuff like that

is that correct?

so putting measures to stop det such as

1) FMIC or uprated IC

2) Water injection Maybe?

3) Fuel additives such as fuel star units

4) computer tuning for more fuel to safe margin the det potential

is this correct?

so the stock internals and stuff should last

how bout the gear box, torsen?? how much can they withstand?

also the standard clutch?

At the fly so engine. normally it's the americans that talk about power at the wheels.

Yes you can runn 400 with stock internals but I'd include all of the above mods including WI. However get it mapped with the WI turned off then have it setup as a safety net in case the intake temps start to get a bit high. The aim is to prevent det completely not reduce it if your sticking with the stock internals as I said the stock pistons are strong but det is their worst enemy.

The stock transmission is pretty strong and can take upward of 550BHP without to may problems

Stock clutch is pretty good but it'll wear out pretty quickly if you do a lot of launches I'd say look at uprating at around 300-330BHP or if you likely to be launching the car alot. They tend to wear out at around 60,000 mile mark on a stock car mainly due to the extra punishment the 4 wheel drive system puts on them.

[Dominos Rox!]

Im from new zealand, and we talk here in terms of at the wheels

so i will assume that all your power talk here in this particular forum which is mainly UK is at the engine, is that ok?

so 400 at the engine is still alot at the eingine, thats 300 KW... a monster:D

oh yes

ok, just wanted to get a fair idea, so WI is a safety margin but getting it mapped with out WI is best.

Have you heard of fuel star?

a product placed in the fuel like before the rail that releases nano particles of tin into the fuel which helps it combust moreeffetively

anyone heard of that?

as for gearbox and diff, they can handle up to 550 with no issues

thats good to hear cos uprating those cost alot of money:D

[Sketchy]

Im from new zealand, and we talk here in terms of at the wheels

so i will assume that all your power talk here in this particular forum which is mainly UK is at the engine, is that ok?

so 400 at the engine is still alot at the eingine, thats 300 KW... a monster:D

oh yes

ok, just wanted to get a fair idea, so WI is a safety margin but getting it mapped with out WI is best.

Have you heard of fuel star?

a product placed in the fuel like before the rail that releases nano particles of tin into the fuel which helps it combust moreeffetively

anyone heard of that?

as for gearbox and diff, they can handle up to 550 with no issues

thats good to hear cos uprating those cost alot of money:D

Yea WI is generally employed as a safety margin. hence you map without it then only use it when you need to bring the temps down a bit, which i would imagine might be quite often over in NZ... :D

I've heard of something like the fuel star thingy, but you'd probably be better off with a liquid Octane booster. You add it to the petrol tank and it increases the octane rating of the fuel your using, hence increasing the fuels det resistance.

If your keeping the stock internals I'd also recommend getting a ECU with Knock control like the motec or Hydra Nemisis. Both have closed loop knock control, i.e. !Removed! ignition when knock(det) detected.

Apexi Power FC is also a common upgrade ECU option but this only has Knock detection not control. It flashes the engine warning light when a user set amount of Knock is detected. However with the stock pistons by the time you know it's happening it could be to late...

At the end of the day though it all comes down to the quality of the mapping it's realitively easy from a mapping point of veiw to get a high max power figure but this is only one very very small part of the map. Driveability mapping is much harder as it's all about tuning the entire map for as much torque as possible including the off boost section. You can normally tell the quaility of a map simply from looking at how the engine responds in the off boost and off-on boost transistion. Also a good map will take into consideration the strength of the engine and get the best out of it without stretching it to destruction...

[dawesy]

im running 470bhp and 380ftlbs on a 205 lump, i am running JE forged pistons and full ARP fastners though.

although i have done some mild port flowing im still running stock manifolds, throttle body, cams and valves.

upto 450 bhp should be fine but as has been said it depends how brave you are, but a point worth noting i have never heard or seen a broken rod or crank from a GT4 or an MR2 that has failed under power