fuel cut and max boost

[MR2Jedi]

I am going to install FCD. the setting is 7. does anyone know at what point of boost the fuel cut will engage? also, does anyone know what the max boost from a stock ct26 is? I was wondering what to set max boost level at for electronic boost controller.. Thanks

[Piddy]

I'm assuming this is an HKS FCD since you are setting it at 7. That generally puts fuel cut at around 17psi if I remember right. Stock CT26 can usually run 15 or 16psi MAX... also kinda depends on what your mods are.

[JekylandHyde]

The max boost you can adjust fuel cut to is 17.7 psi ... the HKS FCD raises it to 17 psi.

The CT26 runs out of it's efficieny range at 15 psi .... so any boost beyond that will not reap significant gains for the increased risk to your engine.

[MR2Jedi]

Thanks Doc...you are right on the button. FCD is a HKS. I will set max boost @15lbs. I'll take all the boost I can get from the stock turbo. not looking for gargantuan HP. but would like to get close to 280-300 horse. I have twin HKS 264 cams to install on a ported,polished head. any idea how much HP/torque that will bring me up to? cody

[JekylandHyde]

The reason not to run more than 15 psi on the CT26 is that the exhaust side is too restrictive and you start generating too much heat (risking detonation).

Installing the 264 cams is going to increase the amount of air the engine can flow ... but it is still going to hit the bottleneck at the turbo.

You are never going to see the full benefits of cams with the CT26. The CT26 is not an appropriate turbo choice if you are trying to reach 280-300 rwhp ... especially if you want that much power reliably.

I wouldn't even recommend the CT20B if you want 300 rwhp.

[MR2Jedi]

I see. will a ported/polished exhaust manifold, and larger diameter exhaust piping be enough to relieve restriction? cody

[JekylandHyde]

The restriction is THE turbo. You can open everything up before it and after it ... and you will still have a restrictive turbo.
The only way to get by it, is to get rid of the turbo.

Sorry for the bad news.

[MR2Jedi]

thats OK. not really bad news, but the correct course to follow. would it be possible to modify the ct26 the meet the flow requirements? if not, which turbo and trims do you recommend?

[MRQtwinturbo]

if ur aiming for around 300rwhp......t3/t4...gt28....tdo6 are all popular turbo upgrades.....but then u will also have to factor in all the supporting mods and tuning costs......keep your car stock as possible.....

[MR2Jedi]

all those turbos require a different flange-correct? are there adapters or does that mean manifold /headers too? I understand the fuel upgrades,and I can afford all these modifications, but I am concerned about fitment. I don't want to have to start chopping up the engine bay to make things fit. and I agree that things should be kept close to stock. I do want to use the HKS 264 cams that I bought. Lord knows I waited long enough for them on back order. what would you suggest I do to reach my goal using these cams to attain HP in the 280-300 range and still have a streetable , reliable MR2?

[Piddy]

Once you get above ~275rwhp you are looking at upgrading your fuel system. Thats where things start to get expensive.

Read this... http://mrcontrols.com/primers/power.htm

[JekylandHyde]

The actual CT26 housing is the problem ... no way to modify that really. The turbos MRQturbo recommended are what you want for 300 rwhp. With your cams, you would not even have to push these turbos hard to get that power. You will need an adapter plate & downpipe to get these turbos onto our cars ... most people sell these turbos as kits for our cars and include everything you need.

You will need fuel upgrades to run 300 rwhp safely.

[MR2Jedi]

thanks very much Doc. very, very helpful. your reputation precedes you...

[JekylandHyde]

Thanks.

I just love MR2s and enjoy sharing information