no low end? - Toyota Nation Forum : Toyota Car and Truck Forums

Diff Operator · 06-28-2005, 01:54 PM

I recently aquireda 93 turbo MR2 and just did the complete tune up. I don't have any prior experience with MR2 Turbos so I'm not sure what the car is supposed to feel like off the line. It seems like when I accelerate from a standing start, the car bogs a lot. It seems fine after the turbo spools somewhere about 3k. I know about turbo lag, I'm just making sure this is normal. Also, my car feels really jerky and doesnt accelerate well for the first minute or so of operation, ideas? -thanks

JekylandHyde · 06-28-2005, 02:02 PM

Well you should never try to push the car until it is up to temps.
If the cars is mostly stock, the ECU is going to retard timing and limit boost until temps are up.

What turbo is on the car? Bogging off the line is a matter of not revving high enough that the turbo will spoll as you let the clutch out.

Diff Operator · 06-28-2005, 02:14 PM

I never try to get on it, when it's cold it just will not pull AT ALL, but good to know it's normal. I have a stock CT26. On a syock car what would be a good launch rpm for a quick, not aggresive launch? I also have the Bosch platinums (just because I had already ordered them before I heard from you) well thanks for the input!

JekylandHyde · 06-28-2005, 02:39 PM

Those Bosch plugs are probably causing you problems.
Get the NGK Coppers (6097) ... they are only a $1.70 or so a piece.

A healthy launch will probably be around 5000 rpms with a clutch slip ... maybe a bit higher.

Diff Operator · 06-28-2005, 04:52 PM

WOW! man that sounds high, probably because my last quick car was a T/A with a lot of torque. Why so high? I'm guessing more weight over the rear helps a lot with this, yeah I have only had the BP's for about 125 miles, it does seem like they aren't performing as well as when new. I guess I'll head up to the store and buy some. Anyone know what a stock turbo 2 should run?(1/4)

***MR2Jedi*** · 06-28-2005, 07:55 PM

upper 14's if all is well and you can drive decently...

JekylandHyde · 06-29-2005, 05:33 AM

Your T/A has 6 or 8 cylinders trying to launch the car ... you have a lot less now and if you want the torque to launch well, you need to launch high. 5000 is not even high.

I launch at 6500s and I have a 2-step that builds 20 psi of boost before I even let the clutch out

PitBull · 06-29-2005, 08:17 AM

You'll know when you launch it right -- you'll feel it

But yes, it takes a little practice. If you don't launch it just right, it feels like the turbo never reaches it's full boost potential by the time you have to shift to 2nd -- at least, that's what it seems like to me on my 100% stock 91...

PitBull

Diff Operator · 06-29-2005, 10:37 AM

So the MR2's tranny is strong enough to withstand 5k launches? What about keeping the throttle pinned in between shifts?

JekylandHyde · 06-29-2005, 10:47 AM

I've launched Hyde at 6000 rpms with my line lock ... locked .... and still managed to do the entire 1/4 mile. Others have pushed over 700 rwhp through our trannies. They are plenty strong.

I have been full throttle shifting from 3->4th for well over a year now.
I did not trust my 2nd gear sycnro to try that. I tried 2->3 twice. Once was perfect and once was almost devastating .. so I did not try again.

You may find this video eductional:
http://www.jekylhyderacing.com/image...forte_1185.mpg

Diff Operator · 06-30-2005, 08:56 AM

Thanks, I still need to get the 6097 NGK copper plugs but held it a little higher to launch and....YOUR RIGHT! Much quicker, made a huge difference! Thats good bc I'm going to the track soon to get a 1/4 baseline run.

JekylandHyde · 06-30-2005, 09:38 AM

Since you are using the stock turbo, you are also going to want to watch your pwoer band. That turbo does not like redline.

You can redline 1st ... 2nd around 6500 and the rest may be around 5500 rpms.
You should be able to notice the point at which it does not pull as strong.

Diff Operator · 07-01-2005, 11:03 AM

Yeah, I noticed that when I dropped the hammer next to a not-so-unattractive young lady on the highway in a Mustang GT. But a lot of stock turbo cars are like that. My buddy was at the track in his WRX and shifted at redline every single time and was running a 14.7. I was there and drove his car, shifted at 7 in first and then 6.5 for next two shifts and dropped his time to a 14.4.

JekylandHyde · 07-01-2005, 11:21 AM

It's not a function of the car or the engine, but rather the turbo sizing ... specifically it's torque curve.

All of the larger turbos I have used have loved to be redlined.
In fact, my current turbo would enjoy going well beyond redline but my engine has issues with that

Diff Operator · 07-01-2005, 01:04 PM

So I just bought the NGKs, about to go install. Where is the actual copper at on the plug? Just curious I know Ihave the right part number 6097.