[Doe_nStein]

X2.Some stock set-ups do rely on back pressure for their performance.Headers should be the last thought AFTER all the other mods are in place.Quick fixes for performance are just that in results.Everyone thinks incorrectly that just by hanging on a cad or muffler they are now in the same place as a guy who knows how to smooth flow a induction system.(head work done,cam that matches,rear end ratio that capitalizes on peak torque/HP ranges,matched injection system,etc.)I just take moves like a exhaust cure alls as a lazy mans fix or one that is totally misinformed. :2:

I want to explain my self alittle better.The real question is does headers on a stock set-up work,at idle-nope.So where do headers really start to work??.What RPM??.How about at 2500 RPM??.Well truthfully not much there either.How about at 3500 RPM-just starting to have somewhat a effect,about 2% or less.My point is like any other engine these are air pumps.Air pumps that need a balanced in and out.Stock air ratios run out of fuel/air by the time headers have any effect.In fact header "could" create a lean condition which is not good for stock engines.The ECU feels it needs to put in more fuel and at best it is still within the limits of the stock injector system which is not enough.That headers also need to have a active 02 sensor.Also there are limits to the stock cam and kit in these engines.So by the time you have reaped any real benefit from headers and their scavenging effect,you have run out of RPM.Got to be mindful that headers are truly for HP and because of that their effect is in the upper RPM ranges.The concept is HP is a peak in the upper RPM ranges.Also small C.I. engines by the nature of their size have a HP peak in the upper RPM ranges.So if you want to get to use say 5 to 7 hp at best.............Well I think you can see what I am saying.No giant killers there.

The idea of a tune on a engine is now and forever will be big picture.Total concept and not just one pc of it.

What is so disheartening to me is a guy that just because it is louder thinks it has more output and walks round with his chest pumped out having done only one thing.It is his mind game that I really don't want to be apart of.Again just my :2:

I realize this is an old post. But it is really wrong. Saying headers don't work on a stock engine is wrong on so many levels simply because it assumes they are ALL the same. Tube length, diameter size, and header configuration all play a part. And I am not sure I have ever seen a header not make power or worse lose power.

 

[Doe_nStein]

Well since there was some 4.3L V-6 Porn earlier I will post some parts I had at one time when I was doing Auto-X and track days with my S-10. I bought a 2 piece intake and heads that were ported, polished, and flow bench tested as a unit by Katech. My plan was to use them on my 10. But the project kinda got derailed and I got rid of them.

 

[WoodButcher]

You're correct Doe, but the tips and tricks need to be viewed in perspective as a whole, just recently on the other forum a fellow mentioned the cold air intake,

"The K &N kit 57-3017-2 fits S10 truck but not exact fit for Astro. k&N claims 7.42 hp increase at 4671 rpm."

My reply was simple,
"A.P., When is the last time you had your astro to 4500 RPM?
You see most of the things like this are unsuited for our uses. Your rig is setup for off road use mostly correct? Which would be better for you if you're out boondocking and have trouble with a dirty air filter? Are you likely to have the things to clean an oil filter or have a spare oiled filter handy? A spare stock is convenient and clean if you needed to carry it along. And where is that 7 hp useful? maybe when you kick it down on the highway for passing, maybe..."

My '93 has a 350 with a stock paper filter pulling cool air from the front of the grill. Underhood heat is not an issue.
My '05 w/ a 6 liter lq4 has a K&N sucking in the hot air from under the hood. I bought it that way and it was tuned as is. At some point I would like to modify a stock airbox and filter to again draw fresh cool air from outside but will then need to have it re-tuned as the air temps will be drastically reduced.
I don't do much off roading but if I did this would be a necessity.

 

[Doe_nStein]

With my 2000 AWD LT all it took was swapping to the 0411 pcm and a bit of transmission shift/lockup tweaking to make the van feel significantly faster along with netting an easy 2+ mpg. However, after doing a bed mounted turbo 4.3l s10, I'm not satisfied with where the van is and thankfully I have another brand new gm8 turbo on hand which will find home where the Astro's muffler currently resides. For the sake of reliability and ease, I'll probably run a maximum of 7psi of boost so I don't need to run an external fueling system (the ol dime had an injector preturbo that came on at 5psi spraying methanol. Felt like vtech kicking in when that happened). My only concern is where I'll put the turbo air intake as I'd rather not have it at the bottom of the van and risk hydrolocking during heavy rains.

How did you go about tuning the 411? Send it off? Do it yourself? IF so how and what did you need to do it?

 

[Doe_nStein]

Stay tuned

 

[EXTREMEODD]

How did you go about tuning the 411? Send it off? Do it yourself? IF so how and what did you need to do it?

Get yourself an "okayish" obd2 Bluetooth module (elm327, vicar, obdlink) and using either a laptop or a desktop with a hella long usb extension you can connect to and pull a copy of your PCM's OS using PCMhammer. From there just download and install tuner pro, then head over to the TunerPro OBDII forums, and find the XDF that matches your OS. In my case I ditched the stock OS and /changed to the 'universal 12212156 os (only OS that will work for any gm v6/v8 platform) and simply copied my stock tables into a 'lean burn' 12212156 copy I had from an s10.

2156 is a nice version to use since that one has the best XDFs available (the most adjustable parameters) not to mention a user on the pcmhacking forums released a patch for it that gives you 2 step launch control (with optional boost building timing retard) up to a 3 bar MAP table among a few other things.

The best part is that the only barrier to entry is a ~$20 obd scanner (I recommend the obdlink lx or mx), anything with an 0411 512k p01/p59 1mb PCM (or one that has been swapped in, it's really not that hard) and some form of a pc/laptop with bluetooth. Everything is essentially open-source and is simple to use once you get the hang of it. Nothing sweeter than perminately disabling a nuisance SEL code, and lowering trans temps with no more than 5 mins of dicking about.

It's one thing to throw on a better flowing intake and exhaust, along with some better injectors, it's another thing entirely once you've adjusted the tune to take advantage of them. I managed to make a ~400hp 4.3l s10 out of maybe 500 in parts and most of that was spent on stuff I didn't use/need. All thanks to open source tuning (and amazon warehouse discounts <3 my pair of GM8 turbos I got for ~75 each).

 

[Slime]

You know, I appreciate your efforts here. There are two very important things that should be mention, first.

Most importantly, proper maintenance. Not enough can be said for staying on top of the maintenance. That includes all fluids, tune-ups, tires, and just keeping everything clean.

Second, the exhaust. The most restrictive part of these vans (and many other cars out there) is the exhaust. It doesn't matter how much air and/or fuel you shove down the intake, if the exhaust holds it up, its all for not. Its the hourglass effect, weakest link in the chain, etc. A lot of people don't like headers but they are the best bang for your buck, period. But there is something else that can be done, replacing that stock catalytic convertor with an aftermarket version. All catalytic converters do the same thing but aftermarket versions flow 3, 4 or 5 times as much as the cheap stock equivalents.

:2:

I like this idea..

 

[stent]

Get yourself an "okayish" obd2 Bluetooth module (elm327, vicar, obdlink) and using either a laptop or a desktop with a hella long usb extension you can connect to and pull a copy of your PCM's OS using PCMhammer. From there just download and install tuner pro, then head over to the TunerPro OBDII forums, and find the XDF that matches your OS. In my case I ditched the stock OS and /changed to the 'universal 12212156 os (only OS that will work for any gm v6/v8 platform) and simply copied my stock tables into a 'lean burn' 12212156 copy I had from an s10.

2156 is a nice version to use since that one has the best XDFs available (the most adjustable parameters) not to mention a user on the pcmhacking forums released a patch for it that gives you 2 step launch control (with optional boost building timing retard) up to a 3 bar MAP table among a few other things.

The best part is that the only barrier to entry is a ~$20 obd scanner (I recommend the obdlink lx or mx), anything with an 0411 512k p01/p59 1mb PCM (or one that has been swapped in, it's really not that hard) and some form of a pc/laptop with bluetooth. Everything is essentially open-source and is simple to use once you get the hang of it. Nothing sweeter than perminately disabling a nuisance SEL code, and lowering trans temps with no more than 5 mins of dicking about.

It's one thing to throw on a better flowing intake and exhaust, along with some better injectors, it's another thing entirely once you've adjusted the tune to take advantage of them. I managed to make a ~400hp 4.3l s10 out of maybe 500 in parts and most of that was spent on stuff I didn't use/need. All thanks to open source tuning (and amazon warehouse discounts <3 my pair of GM8 turbos I got for ~75 each).

to EXTREMEODD :
i was working on making a wiring pin chart for swapping an "0411" PCM into a '99 van but had to take a break because i couldn't see what i was doing 'cause of cataracts.

couldn't see the numbers on the connectors to continue :

now that i can see! what i'm doing i'll be getting after it again. i see! that you have swapped an 0411 into your 2002 - do you have a finished swap chart???
here's the link for the thread i was posting on to show where i got to :
changing 1999 "black box" VCM to 2002...

 

[EXTREMEODD]

Sent a PM, I paid lextech on the gmt forums for my copy as when I tried doing it on my own the first time on an s10, it didn't go so well. There are 5 dark green wires that are easy to get mixed if your're not careful.


EDIT: Forgot to mention the snail has been mounted under the van for a few days and even at 5psi it's like a different van. I'm holding off on pictures for at the moment as much of the cold side looks like hell since I was running a cheap 120v inverter welder on cheap harbor freight wire, connected to one of those thin lamp extension cords. Spent more time grinding than I did welding. The gist of the setup is I made a pie cut 90 that goes straight from the plastic bonnet down to the lower pass side of the motor where a regular 90 is welded, then there is a single silicone connector for the long af single welded piece(s) of steel that directly attach to the turbo with the 2nd of two silicone couplers. Due to half assing the pipe to bonnet (misplaced my coupler but had an exhaust adapter that fit snugly so that was temoorarely epoixed into the bonnett. Accidentally hit 14-15 psi despite the waste gate having no boost refrencel but thakfuly no harm was done and glue has broken away some leaving me with a near perfecf 5psi of boost.
Until I get my old 'is that a f***ing injector on your pre turbo intake elbow' setup going again, I temp rigged up a cheap inline 'bosch' style fuel pump that draws from a jug of VP Racing 80% ethanol hand sanitizer that I have like 30 gallons of and that runs to a single mister nozzle that is clamped onto the one connector on the bonnet. I\d MUCH rather have it spray preturbo but I did this as a bit of a stopgap until this weekend. Should be getting ~30g of methanol for next to nothing and I plan on spraying some amount of 50/50 - 70-30 meth/water into the turbo intake. Also this weekend I'm going to finally cut the cat converter out and replace it with a test pipe, thefts are bad around here, I could use the cash but most importantly: the damn thing is robbing my turbo of heat That and I'm like 90% done building from the turbo to the stock exhaust. its been a challenge due to the inlet and outlet on the gm are on the same side. once that is on my goal of a mostly sleeper astro will be compete. I feel no desire to see what the 4.3l in the astro can take as I know my same year s10's motor held 15-17psi all day no problem