Comp ratios/ ecu issues?!

[dean]

Installing v2 blower on 1uzfe stock ecu, using blow through on the afm, with stock pistons at current compression ratio of 10:1 only small amounts of boost can be ran correct,?!
But I'f I change the pistons to 8.5:1 and ran higher boost will the ecu have issues with it or not ?!

 

[ash]

Installing v2 blower on 1uzfe stock ecu, using blow through on the afm, with stock pistons at current compression ratio of 10:1 only small amounts of boost can be ran correct,?!
But I'f I change the pistons to 8.5:1 and ran higher boost will the ecu have issues with it or not ?!

yes,
or
pull some timing will the high compression ratio
therefore you will have more off boost engine response

 

[dean]

Write that again mate, first part makes no sense,

 

[ash]

Write that again mate, first part makes no sense,

me?
change the will > to with

 

[gloverman]

With aftermarket ECU and good tuning the stock series 1 motors love boost. I ran 10psi most of the time and sometimes 15 psi. Cheers

 

[dean]

what ecu gloverman?

 

[spf_lexus]

what gloverman said ^^^

10:1 is fine as long as its tuned to suit.

If you drop CR on a stcok ECU you will lose a lot of low end. Since the v2 is high rpm dependant, your car will drive like a honda. nothing below 4 grand.

 

[gloverman]

Link Xtreme on my turbo one one and Ive done another twin turbo with a link Storm and a couple of supercharged ones with link LEM V5 and a LEM G3 and two supercharged ones with G3 LINKPLUS. All stock internal series 1 motors. Turbo is my perference. Cheers

 

[spf_lexus]

If anything, keep the engine 100% stock... + add boost and its fine up to about 8psi. When you start changing CR and adding cams, etc etc. the ECU becomes less and less useful.

Lextreme and myself tried starting his 5.2L with cams and lower CR On stock ECU and stock injectors. The only way to keep it running was to rev it to 5,000rpm where it then chugged and died. It ran like 9:1 pig rich too. The ECU was upside down... since then he had it tuned with an AEM standalone.

 

[XR8tt]

A GOOD ECU and tune is what keeps engines alive especially on boosted engines...
I cannot believe sooo many that try to keep std ECU ..
Especially one which basically connot be tuned.
Any serious power required an ECU to read boost or engine failure quickly follows..
Which is what gives modding / forced induction a bad name ..
In most cases a GOOD tuner can do a better job with a cheaper ECU than a
good ECU and bad tune...
The advance curve and fuel curve is so different N/A to forced induction engine
it's not funny..
On a 8.8 comp engine with 20Lb boost & at peak torque the timing is approx 9* and as RPM rise the advance curve increases...
An an N/A engine would be close to 25 / 30* at this point in RPM...
Which would kill a forced induction engine...
AFR's are way too lean at this point which doesn't help !!!
Lowering comp and fitting FMU is old tech way around but still very
unreliable on modern engines...

 

[spf_lexus]

A GOOD ECU and tune is what keeps engines alive especially on boosted engines...
I cannot believe sooo many that try to keep std ECU ..
Especially one which basically connot be tuned.
Any serious power required an ECU to read boost or engine failure quickly follows..
Which is what gives modding / forced induction a bad name ..
In most cases a GOOD tuner can do a better job with a cheaper ECU than a
good ECU and bad tune...
The advance curve and fuel curve is so different N/A to forced induction engine
it's not funny..
On a 8.8 comp engine with 20Lb boost & at peak torque the timing is approx 9* and as RPM rise the advance curve increases...
An an N/A engine would be close to 25 / 30* at this point in RPM...
Which would kill a forced induction engine...
AFR's are way too lean at this point which doesn't help !!!
Lowering comp and fitting FMU is old tech way around but still very

^^^ Well put.


I ran the FMU route and touted it as the best "band for buck" solution until I had a diaphtam failure and ended up putting out a massive engine fire with my just purchased groceries. It was a sad story and could have easily been fixed w/ a proper tune.

yes,
or
pull some timing will the high compression ratio
therefore you will have more off boost engine response

I think Ash was referring to boost with the factory 10:1 CR. as you reach redline, pull the timing to keep it safe.

 

[kc95sc400]

A GOOD ECU and tune is what keeps engines alive especially on boosted engines...
I cannot believe sooo many that try to keep std ECU ..
Especially one which basically connot be tuned.
Any serious power required an ECU to read boost or engine failure quickly follows..
Which is what gives modding / forced induction a bad name ..
In most cases a GOOD tuner can do a better job with a cheaper ECU than a
good ECU and bad tune...
The advance curve and fuel curve is so different N/A to forced induction engine
it's not funny..
On a 8.8 comp engine with 20Lb boost & at peak torque the timing is approx 9* and as RPM rise the advance curve increases...
An an N/A engine would be close to 25 / 30* at this point in RPM...
Which would kill a forced induction engine...
AFR's are way too lean at this point which doesn't help !!!
Lowering comp and fitting FMU is old tech way around but still very
unreliable on modern engines...

I've said it more than once but......

I ran 12psi and ran low 12's for a few years and 50-60 thousand miles with the stock motor, stock 95 ECU and a MAFTPro (for sale, ). This is with 440cc injectors. This also includes several 100 track runs!

It wasn't until I got an aftermarket ECU and got a little timing happy that I hurt the motor.

KC

 

[XR8tt]

Quote ...
It wasn't until I got an aftermarket ECU and got a little timing happy that I hurt the motor.

Quote ..
In most cases a GOOD tuner can do a better job with a cheaper ECU than a
good ECU and bad tune...

Yep...
A bad tune WILL do it !!!!

 

[kc95sc400]

Quote ...
It wasn't until I got an aftermarket ECU and got a little timing happy that I hurt the motor.

Quote ..
In most cases a GOOD tuner can do a better job with a cheaper ECU than a
good ECU and bad tune...

Yep...
A bad tune WILL do it !!!!

Well, to be honest I can't really say that the tune had anything to do with it. Could of just been the fact that I had been beating on it for so long and it had over 160,000 miles on it. It didn't blow up or anything, still ran pretty good actually.

My point was that I was making plenty of power on the stock ECU, ran 12.0's on the stock ECU.

I didn't gain or lose anything really with the Adaptronic as far as track times.

Don't get me wrong, I like having more tuning flexability I'm just saying that I think that the stock ECU is underestimated.

KC

 

[XR8tt]

You did what can be done to improve std ECU tune etc!!
With maf pro and injectors etc...
If only the timing can easily be tuned...

 

[boXXer]

What sort of torque and power would you see on a completely STD engine with say, 10psi of boost?

 

[XR8tt]

What sort of torque and power would you see on a completely STD engine with say, 10psi of boost?

That's where tune comes into it...
Adding 70% more air with the same tune...
Well put it this way.. Bara pressure at sea level is 14.7 ..
Then add another 10Lb !!
I would say ???? 6 Lb and run a rising [FMU] rate reg to increase
fuel pressure .. Is a cheap fix...
Trouble with cheap fixes ??? They tend to be unreliable...