[Bimmer Nerd]

So for the past couple of day's i've been doing some research between the tunes (Giac, JB3, procede, OE, dinan) and i've noticed that piggyback's can run much higher PSI than flash.
For example, JB3/procede guys can easily run 16+PSI, but most flash tunes only go up to 14 PSI, why is that ? Is there something that piggyback can do that the flash can not, meaning thats why it runs a lower PSI ?

Thanks

[iwanna335]

Now you've done it I'm sure there will be some heated argument on this!!

[Bavarian E92]

Well Dinan tune is more conservative because they provide you with a warranty. Running stock turbo's past 16PSI is asking for trouble. The other tunes are way more customizable so they allow you to reach the absolute maximum tuning potential.

[Bimmer Nerd]

Originally Posted by iwanna335

Now you've done it I'm sure there will be some heated argument on this!!

This isn't another JB3 vs Procede thread, ! its just a general question related to tunes, so i don't see a reason for anyone to get heated, rather than gain some knowledge.

Originally Posted by Bavarian E92

Well Dinan tune is more conservative because they provide you with a warranty. Running stock turbo's past 16PSI is asking for trouble. The other tunes are way more customizable so they allow you to reach the absolute maximum tuning potential.

I understand the warranty factors, but what i was wondering is that, why can't lets say GIAC or OE tuning go to 16PSI on tunes that they provide for customers, since they don't have to worry as much as dinan.

[iwanna335]

Originally Posted by Bimmer Nerd

why can't lets say GIAC or OE tuning go to 16PSI on tunes that they provide for customers, since they don't have to worry as much as dinan.

They can, but choose not to. They make power by changing A/F ratios, timing, and boost to name a few.
My understanding of piggyback systems is they trick the DME/ECU (whatever its called) into increasing boost when it isn't needed those increasing HP.
Once again I'll leave it to the experts to answer, this is just my limited knowledge of the subject and my "cliff notes" version.

[RoundelM3]

The higher the boost on the turbos, the more heat generated, which not only is hard on the turbos, it's also not good for the rest of the engine in general. Adding additional cooling capacity (oil cooler/intercooler) can help offset that, but according to those in the know, 14 PSI is the practical limit for maintaining longevity of engine components with stock cooling. Dinan, for instance, requires their higher-capacity oil cooler and larger intercooler before they'll load their Stage 3 programming on a car. Now, that may be viewed as a marketing ploy, but Steve Dinan has quite a few years' experience tuning BMWs for endurance racing (LeMans, Daytona, etc.), so he probably knows what he's talking about.

Heck, you can tune a Honda Civic engine with a turbo setup and get 700 hp. out of it...for about 100 miles or 100 minutes, whichever comes first. Thing is, you can get Honda Civic engines for nickels and dimes, not the megabucks that you'd pay for a BMW engine. Those higher boost pressures from the piggyback units are an option, not necessarily intended to be run on a constant basis.

That said, I'm curious about the higher-pressure tunes and oil/water temperatures. For those running 16 PSI and above, do you notice significant increases in temperatures and do your tunes back off a bit to keep from overdoing it or is there some other way of holding temperatures down to safe levels without resorting to alcohol/water injection?

[k726]

Flash tunes are generally more conservative. History will show this.

[cn555ic]

Originally Posted by Bimmer Nerd

So for the past couple of day's i've been doing some research between the tunes (Giac, JB3, procede, OE, dinan) and i've noticed that piggyback's can run much higher PSI than flash.
For example, JB3/procede guys can easily run 16+PSI, but most flash tunes only go up to 14 PSI, why is that ? Is there something that piggyback can do that the flash can not, meaning thats why it runs a lower PSI ?

Thanks

Thats not true...I seen GIAC flash go as high as 16.5 on meth

[jblackwell]

Originally Posted by cn555ic

Thats not true...I seen GIAC flash go as high as 16.5 on meth

+1... Look here.

http://www.e90post.com/forums/showthread.php?t=419780

[marcel b]

Originally Posted by jblackwell

+1... Look here.

http://www.e90post.com/forums/showthread.php?t=419780

indeed, and how I read it, the 16+ psi is without meth

[Bimmer Nerd]

Basically 14 PSI is the "recommended" level for people that want to keep the engine/turbo's running for a long time.

16+ PSI is for people that want the power, they want it NOW and they probably have a lease

Thanks everyone

[cn555ic]

Originally Posted by Bimmer Nerd

Basically 14 PSI is the "recommended" level for people that want to keep the engine/turbo's running for a long time.

16+ PSI is for people that want the power, they want it NOW and they probably have a lease

Thanks everyone

Thats not entirely true...Running race gas and or meth, you can effectively run 16 psi safely IMO, I run that quite often and I own the car..

[Bimmer Nerd]

Originally Posted by cn555ic

Thats not entirely true...Running race gas and or meth, you can effectively run 16 psi safely IMO, I run that quite often and I own the car..

hahahah i was joking

Basically, you can't go wrong with any of the tunes, its just a matter of personal preference

BTW how much are you putting down to the wheels ?

[cn555ic]

Originally Posted by Bimmer Nerd

hahahah i was joking

Basically, you can't go wrong with any of the tunes, its just a matter of personal preference

BTW how much are you putting down to the wheels ?

No clue at the moment...I mod my car for hobby sake and while it all good and dandy that people post their dyno numbers, for me a butt dyno is more than suffice! If I had to put a number I would think around 450+ hp/rwhp and I am tuned to the conservative side as for boost psi..

[SleepyE90]

All flash tunes that couldn't go above 14psi were rebranded/stolen and modified flashes based off an early AC Schnitzer tune that was conservative.

[joec500]

People get so caught up on PSI, I was under the impression that HP is not strictly dependent on boost pressure. For example I am sure you could have one car making 14PSI and another at 16PSI, where the 14PSI car makes more power depending on how the tunes are implemented and setup. I am not a tuning expert, so it would be interesting to hear what the pros have to say.

[RoundelM3]

Boost pressure is one of the more significant items in a tune for any turbo engine...but fuel and ignition maps have to change with higher boost pressure or detonation can occur and destroy the engine (extreme case) or cause overheating and less performance than would be gained with fuel and timing changes appropriate for the boost level.

[enrita]

Originally Posted by Bimmer Nerd

So for the past couple of day's i've been doing some research between the tunes (Giac, JB3, procede, OE, dinan) and i've noticed that piggyback's can run much higher PSI than flash.
For example, JB3/procede guys can easily run 16+PSI, but most flash tunes only go up to 14 PSI, why is that ? Is there something that piggyback can do that the flash can not, meaning thats why it runs a lower PSI ?

Thanks

Because the DME tables are only written up to 1 Bar/14.5 psi. In order to go above you need to rewrite them all which is very costly and advanced.
Only GIAC and Evolve i think managed to do this.

[bren335i]

Originally Posted by enrita

Because the DME tables are only written up to 1 Bar/14.5 psi. In order to go above you need to rewrite them all which is very costly and advanced.
Only GIAC and Evolve i think managed to do this.

Sorry dude but the above is misinformation - we've been over this on the other site before.

[Doug007]

As far as I can tell, both flash tunes and piggy backs are limited by the maximum pressure on the MAP (manifold air pressure) sensor, which is somewhere around 1.55 bar/22.5 psig.

The boost setpoint/target is at the discretion of the tuner. It seems 14-15 psig is common for otherwise stock cars. 16+ is commonly used for cars with methanol/water injection and/or high octane race gas.

High boost levels at high rpm require very high turbocharger rpms, which is Dinan's stated reason for limiting boost to around 14.5 psig.

[enrita]

Originally Posted by bren335i

Sorry dude but the above is misinformation - we've been over this on the other site before.

oh really? than why all the other Flash tuners do not go above that? I know a couple personally that told me they are not interested in investing money to pass that limit because 90% of the customers do not want to heavily modify their cars and are happy with 14 psi with an otherwise stock car.

[Mr. 5]

Originally Posted by enrita

Because the DME tables are only written up to 1 Bar/14.5 psi. In order to go above you need to rewrite them all which is very costly and advanced.
Only GIAC and Evolve i think managed to do this.

This is correct.