Whippled 496

iTrader: (4)

If your not boosted, i dont think there is any benifit.

dewmanshu

iTrader: (4)

IMO, right. Seems to me for MOST here, 2bar is more of a tuning thing, not a ," I maxed out my maf and need a way to properly fuel now". You have alot of fueling options with 2bar, maybe options is a bad word, maybe more resolution that is editable. You can really get your hands into the ve table, rather than messing with the smooth curve of the maf. Unless you are into messing with tuning your truck I wouldn't mess with 2bar. Unless you are certain you are near or are maxing out the maf.

Quote:

Originally Posted by Whippled 496

If your not boosted, i dont think there is any benifit.

he is boosted, but what he is asking is, if boosted...but not maxing out the maf with what air flow he does have, is it benefitial to go 2bar.

I gotta copy and paste erik's explanation to my desktop, he explains that **** so well.

Whippled 496

iTrader: (4)

oh, is that what "procharged 5.3" means? LMAO! See thats what happens when someone (me) tries to help, that cant even figure out his own problems.

Sorry man, i misunderstood your question and didnt read your sig......im going back to filling my engine bay with expanding foam seal.

FlaBouy

I agree with most of what is posted here... except.. I can see a need for a 2 bar in a N/A motor application in an engine with big cams.. A couple of guys on HPT are seeing 125-130 kPA ranges..

I am one of those unfortunate souls who are maxing/exceeding the limits of the MAF (60 lb/min) I see 65 lb/min or so at 12500 (HZ) quite often.. I also logged a 190 kPA level this morning in HP Tuners pulling a sub-5 second 0-60 mph run...

The 2 BAR OS is my next step performance wise and for anyone running FI, I think it is a wise invewstment... BTW, I run my 2 BAR MAP in parrallel with my stock MAP, just to get an input into HPT....

TurboBerserker

iTrader: (1)

Well, you would still see *some* benefit, just not as much.

The way the PCM fuels the engine is this:

For all MAF readings < whatever the first limit is in your OS (~1200 stock, I think), ignore the MAF, use the VE table - the MAF at this point is unreliable (not flowing enough air for accuracy I think).

Between that point and 4000rpm (again the upper limit on the OS, stock represented here), blend the MAF and the VE table.

For > 4000 use the MAF.

So having a 2 bar map, and hitting boost in a non-maf maxed truck (say that 3 times fast!), you would have more resolution before 4000rpm, but after that, it's all MAF again with the same limits.

BTW, if you are set up with a draw through MAF (i.e. air cleaner -> MAF -> SC -> intake) you probably want to go SD imo if you are going to run big boost, because the MAF is going to be waaay out of whack for how much air density you are actually providing at high boost. This is my opinion -- I haven't tested it or anything ")

TurboBerserker

iTrader: (1)

That is interesting. My only guess as to how this possible is that they are running so much intake duration that the valve is still open during the compression stroke. Anyone figured out how they are boosting themselves without a compressor?

Allgonoshow

iTrader: (1)

2 bar for dummies...not available at walmart
so i'm boosted.
i have a afr and boost gauge installed and otc scanner at work.
at what point do i know i can benefit from a 2 bar maf.
can nelson tune me,mail order for 2 bar maf.
i have nor the time or inclination now to start my own tuning.
my wot afr is very low 12's with a dip to 11.9x at shift[stock]
wot boost is 8 psi
timing at wot is 16 deg
iats 130
ect 190
burns tires thru 1st gear[2wd] and first part of second.
BUT i think there is more in it.
i'm thinking with a little more rich fuel I might get a little more timing.
if i run with scanner and watch maf what would i look for.
given the above, where do i go next before meth.

don't mean to jack the thread but i think it's relavant to the topic for me and others

TurboBerserker

iTrader: (1)

Anyone running FI can benefit from a 2 bar MAP and SD tune.

It CAN NOT be done via mail order, and if your tuner tells you he can, get a new tuner because he doesn't know what he's getting in to.

That's cool -- tuning can be a major PITA. A local dyno tuner with expertise in FI can getcha taken care of.

A little lean for a turbo. Leaner than I'd be comfortable with for a s/c (the 12's anyway). Timing is the "standard" starting point for FI. IAT's are a bit high considering 8psi and some kind of intercooler (?) for more timing -- I mean maybe a few *'s but that won't be much.

Allgonoshow

iTrader: (1)

A little lean for a turbo. Leaner than I'd be comfortable with for a s/c (the 12's anyway). Timing is the "standard" starting point for FI. IAT's are a bit high considering 8psi and some kind of intercooler (?) for more timing -- I mean maybe a few *'s but that won't be much.[/QUOTE]

remember, it's a radix so iat's are measured in the intake beyond the blower.\
it seems 1 deg of timing in similar setups are worth about 10 hp, so it may be worth searching for a little.
the reason I got the nelson tune in the 1st place was only to get some timing over the radix tune, i got 2 deg over stock radix tune.
so a 2bar maf is not in the cards for me, do you think, given the above
i should try and get nelson to squeeze me some more fuel/timing or leave it alone.
Eric, thanx for you help, as i said , 2bar for tummies.

cablebandit

iTrader: (37)

Al, you are only looking at a total hp figure of maybe 400-450rwhp...not worth the daily driver headaches of SD tune. I was going to do it on mine but i think the progressive alky instead of on/off i have now will serve my purpose.