greco96

at what point do you know when you have to much boost. If you have the right amount of fuel( using a a/f gauge and a ecm) and the temps are right. how do you know how much boost a stock sportage or any motor for that fact can take. I know if it knocks thats bad and the high engine temps but at what point before you blow the head. I will have a sportage and the plan is to start at 7psi then move to 9psi. but how high can I go. I know i cant go to the 30's but could i get to the mid teens? how do you know how much the connecting rods and other items can take. I understand to increase it little by little but i have not found any infor on others that have done this motor so i am in new grounds.

turbomini

wwhat kinda car would be a good start to go with lol but depending on your set up is how high you can go

greco96

the car is a kia sportage. I have a made manifold using a t3/t4 turbo. I also have a megasquirt ecu but have not hooked it up. I will be using a wideband to see a/f and boost gauge to see boost. external wastegate is set at 7psi but will be changed to 9. I dont know what the max the engine can handle and want to know what to check before I get to the blown up point.

boosted86

If you have looked for it, and can't find the answers, then time to start doing your own "research"

Megasquirt requires a great deal of knowledge to fully comprehend and use correctly. Though it is an AWESOME tool for the DIY turbo setups.

Your best bet, is to start getting real good at reading plugs. Start with low boost, overcompensate your fueling needs. You will come to a point, in higher boost, where you will be running rich almost 90% of the time, until you are at WOT. That is why high boost can be a double-edged sword.

If you are planning to make the Sportage a "street machine" I would suggest having the heads ported, or at least cleaned up, the intake cleaned up, and reworking the exhaust to suit. Three inch exhaust is always nice, but with a T3/T4 it will almost be necessary because they are a larger turbo, needing the exhaust and intake flow to spool it fully and correctly.

Plug reading is a very good tool to see the effects of boost and your settings are having on your motor. Also the wideband will help, as you will get real-time data about wehat fuel you are running, and can indicate a bad situation (such as lean-out, causing detonation) before it happens.

greco96

thanks that is kind of what I thought. making sure the mix is right for the cylinder. I understand the megasquirt for tuning its just to dam cold up here to install it yet. I dont know what the stock rods and rings can handle but i guess for the first time it will be guess work> just have to keep mix good.

quicksilvia

you will need a wideband AFR gauge to monitor your air/fuel mix. at WOT try and stay at 12.8 and richer; or you may risk detonation

greco96

I have a wideband from innovate I just hooked up. So far at 5psi it's at around 14 a/r. I have found a dead spot when I get off the thottle and below 1000rpms it goes lean. I plan to add the megasquirt to richen up the mix. I have not changed the injectors yet which is in the plan and I know the stock pressure may be lower then needed.

greco96

ran the car for the first time everything works fine. Next step is the get the mega squirt to work with the system

MPR

Boost is relative to how much power you are making. The question you should be asking is "how much power can I make with this engine?"

That depends on the strength, quality, design and materials used for the internals. If you don't rev the engine any higher than stock, the rods should handle quite a bit. The thing to remember is, the more power you make the more heat is produced. The longer you keep your foot on the loud pedal for any length of time, the closer you come to melting a piston or blowing it up.

To be safe, keep the power increase modest, make sure the engine is tuned properly (good control of AFR at all times) and don't beat on the engine excessively and you should be fine.

sohc_turd

Based on the compression ratio and bore size, you might be able to make an edumacated guess as to a HP goal. Once you determine that #, make sure you have the proper fuel and fuel management to support those goals.

I think thats the joy of boosting, you can take any old turd motor and make a respectable amount of power out of it, given that you know what you are doing. I'd personally shoot for an extra 100whp right off the bat.