Excuse me for not introducing myself first
I'm currently working on building a 2VZ engine that will be fitted in my MR2... And basically, I have no experience with working on cars or anything. But so far I managed to pull the engine out of the donor car, and tearing the engine apart. Waiting for an engine revision kit with ROSS pistons, Toga HV pump and some other nice goodies. One of the things I found is that there aren't a lot of people that have tuned the shit out of their 2VZ. Or at least, if there are, they won't tell on this forum! Or I completely missed it...
But tuning an engine is done by pioneers like you guys. And you guys gained knowledge on it when doing it! I think it would be a nice thing to show us some of your knowledge instead of kicking JCR's idea down. Tell him what he really needs and tell about what NOT to do.
I never turbo'd an engine before as well, heck, I even didn't build an engine yet. But since people do write stuff I'm sure I would be able to get a turbo working. Perhaps the engine would blow up on me straight away but hey, I would certainly learn of it! (I agree with not doing it if you don't have a spare car).
JCR, my do's would be (but hey, I never done it and you might as well blow your engine this way... Never trust people that claim they have no automotive skills
):
* measure the maximum exhaust gas temp when the car is still N/A (install a gauge or so in your exhaustheader)
* research how much HP you can run with stock injectors
* research what must be done to measure the air that the engine sucks in. The ECU currently probably measures the vacuum that is created but I think you'd be better off with some kind of MAF conversion kit that connects to your stock ECU. You might need that since your ECU measures the vacuum and not the boost. You also need the ability to alter the A/F ratio freely.
* research how to drill an oil tap and oil return to feed your turbo with. Note that you just need a few PSI of oil pressure to feed the turbo. Too much pressure will destroy it. Also, use engine oil that is meant for turbo'd cars.
* your engine sure has watercooling. 99% of today's engines have... Unless you get yourself a ball bearing turbo you gonna need to tap the water to cool the turbo!
* Get the header and bolt on a turbo that fits your engine size! (but keep the temp gauge between engine and turbo!) I wouldn't go much higher than 5PSI in first place and don't expect the engine to be strong enough to take more than 1.25-1.5 times your current torque and power.
* Fit an intercooler that's big enough to cool your intake air.
* If you don't lower your compression, get a device that enables you to retard your ignition timing! You can get devices that will retard it proportionally with your boost.
* Get a boost gauge
* Get a oil pressure gauge
* Oh and look into dump valves and wastegates.
When everything is connected, make sure you get 12:1 (very rich) A/F ratio, make sure your ignition is retarded to the maximum and really don't run much boost.
Then give it a go! Take an eye on the exhaust temp gauge. I think it is best to keep the temperature in the same range as it did stock. Perhaps it no problem to have it up to 10% higher but I don't know! Now, you could tune it by 1) having a less retarded ignition 2) run higher A/F ratio. 3) increase boost.
Never run more boost than your injectors can handle! I.E. If you currently have 120HP, and the injectors can inject just enough for doing 150HP, don't run more than (150/120)*14-14= 3.5 PSI of boost
My theory behind this: When adding more mixture in the cilinder, the combustion temp and cilinder pressure will rise. You don't want this to be too much since Toyota only has *some* tolerance. To lower cilinder pressure you can lower static compression, but retarding the ignition does kind of the same. Richer fuel mixture cools down the combustion temp as well. The big intercooler makes sure the air is cooled sufficiently and thus not adding to a higher combustion temp.
In my opinion you need some specialized devices to get the A/F ratio tuned correctly. Also, perhaps you have to change the O2 sensor since your stock ECU might not like the rich A/F ratio and decide to get it leaner....
Have fun doing it and make sure you have a running spare car... Or a bike or so...
Ok guru's I would like to know how far I could get using these theories... Am I forgetting important stuff?
reg,
Danny
turbo 3s-fe
ah yeah about that
Linear Mode
