FI tuning question

[Sportsguy83]

Anytime you are pushing one of this motors over 400 WHP, you are risking it.

A rock solid tune will keep you as safe as possible, but the possibility of it breaking is still there. If you realistically would have no way AT ALL to pay for a motor failure, I would keep it at spring pressure (7 psi or so) and call it a day.

I am pushing 500 whp, but I'm not expecting that to last forever... In a few years, when we have enough data to know what are the real limits of this motor then we can make those bold statements, this engine takes XXX amount of power, timing etc... and still be safe...

So far, we are all experimenting with it. I would say from what I've seen so far, a 300 whp tune on pumpgas with a reputable good tuner, is a pretty rock solid setup. E85 for added conservatism and 350. As a side note, auto trans cooling should be address when getting close to 300 whp.


A tune itself does not kill an engine... It's the results of a bad tune that can blow an engine. An aggressive tune with a lot of timing will knock, and when you are pushing 12 PSI of boost and it knocks at 7K RPMs, its not a pretty thing... That is a results of a bad tune. An E85 tune that goes past MBT, will make great power, but will go past what is considered safe, and its a the ragged edge of windowing the block.

BUT, consider that even with a good tune when you start pushing a lot of HP, the engine components might just give without knocking or anything because its just too much pressure on cast and not forged components.

[s2d4]

Originally Posted by Fear

Its not an "issue" thread... Its a "can the tune bend rods"

Yes.

Originally Posted by Fear

I was told by the tunner they pull timing to cut power to prevent rods from bending...

They may need to do more than that depending on boost, fuel quality.

[sw20kosh]

like sportsguy said ... around 300 whp 93 pump (270 91 pump) and 350 whp e85 should be relatively safe and rods should not bend. These are conservative preservative goals. Many people go beyond that for personal satisfaction, not reliability. =)

[Fear]

Originally Posted by sw20kosh

like sportsguy said ... around 300 whp 93 pump (270 91 pump) and 350 whp e85 should be relatively safe and rods should not bend. These are conservative preservative goals. Many people go beyond that for personal satisfaction, not reliability. =)

This is right inline with what i was bhoping to hear.

Thank you all for the info, like i said i wasn't and still am not pointing fingers or attempting to start a shit storm.

I was under the impression these motors were alot stronger than this.

[King Tut]

Originally Posted by Fear

I understand that, but two motors have failed within 1 month of the tune. Shop says it the rods and not the tune. I'm just trying to get educated, not point fingers

What were the details on these two motors? What fuel and how much power were they making?

[sw20kosh]

Originally Posted by Fear

This is right inline with what i was bhoping to hear.

Thank you all for the info, like i said i wasn't and still am not pointing fingers or attempting to start a shit storm.

I was under the impression these motors were alot stronger than this.

They might be. It is too soon to tell. We will know after more people go FI and test the limits. So far there are a few people at 400 whp that are doing just fine. For now.

[xwd]

Originally Posted by Fear

This is right inline with what i was bhoping to hear.

Thank you all for the info, like i said i wasn't and still am not pointing fingers or attempting to start a shit storm.

I was under the impression these motors were alot stronger than this.

The rods are the weak part of the motor, that has been determined. A couple of shops, one being FBM, have said they have seen failures at high HP and failures at low HP when boosted, even with good tunes. It's kind of like roulette I guess but the good thing is the failures seem to be more isolated than not.
Tunes and running too much boost can definitely play a part in it. People have broken rods even with supercharged setups.


Junior, very experienced tuner who did the P&L cars at Prime Motoring, specifically tuned the cars so the onset of boost/torque/power wasn't so abrupt and I know others have done the same.

At the end of the day you have to pay to play, it's unfortunate the rods are the weak part because it can trash the whole engine including the heads in a hurry.

[Fear]

Originally Posted by King Tut

What were the details on these two motors? What fuel and how much power were they making?

E85, high 300 range

[jamesm]

Also it's important to note that how you use the car is a very important factor. The guys driving around at 400+whp (myself included) aren't tracking their cars on that boost, at least most of them aren't . It's one thing to have a few maps, drive around daily at 10psi and kick it up to 18 for the occasional highway pull. Actually tracking the car for 20-30 minute sessions at any boost level is a lot more dangerous. My good friend blew a basically stock, untuned engine at the Dragon just driving hard. It happens, and it has as much to do with how it's used as with how it's tuned, though those are the two big factors. The best you can do is just make sure the tune is safe, and not turn up the boost unless you have the cash on hand to fix what may (or may not) come of it.

[Ironsquid]

Originally Posted by jamesm

The guys driving around at 400+whp (myself included) aren't tracking their cars on that boost

whoa whoa, easy bro

[jamesm]

Originally Posted by Ironsquid

whoa whoa, easy bro

well.. there's always the green guy. he's just weird.

[cdrazic93]

Originally Posted by jamesm

Also it's important to note that how you use the car is a very important factor. The guys driving around at 400+whp (myself included) aren't tracking their cars on that boost, at least most of them aren't . It's one thing to have a few maps, drive around daily at 10psi and kick it up to 18 for the occasional highway pull. Actually tracking the car for 20-30 minute sessions at any boost level is a lot more dangerous.

This^

Everything in moderation. With great power (whp too) comes great responsability.

If you want to run 400whp or 500whp don't build the engine to max it's efficiency out at that level. Build the engine to sustain that kind of power without breaking a sweat. Want 400whp? Build for 550. Want 500 whp? Build for 650.

[cdrazic93]

Originally Posted by jamesm

well.. there's always the green guy. he's just weird.

Kinda reminds me of the hulk.

[Ironsquid]

Talk about me like I'm not here, it's fine. First you go out to Kobes without me, and now this.

I demand tater salad.

Edit: and dat shit better have bacon