4g61t.org

me and sutiban (another board member with as 4g15 summit) got some tbs from the junkers from some 1.8 dsms, its only been one night at about 65F outside temp, we didnt reset the ecu in fear that the computer would take longer to relize the new hardware. has anyone had these problems of hunting idle and the rpms slowly hiking(to redline), how do you calm down a 1.8 tb'ed 4g15, we also did a coolant loop bypass( i did this on my old neon with no bad results in cold weather), how long should the ecu take to relize it, should we reset the ecu, should we reset the idle or should we let the ecu learn it all by itself- buy the way we have the 92 year 12v version and 94 tbs. by the way the engine was systematically searching for the best setup(this was cool)the idle hikes would change thier pulse and beat every few seconds it was kinda like music, it slowly change to a different beat about every 10 seconds.

_________________
4g61t.org
4g61t.com

usually 20 min after a change like that it smartens up...

thx man works good now. i ajusted the idle its almost purring like a kitty, low end power is up probly 3 hp, and it dosnt cut out if i start out in first with out raising the rpms.high end didnt gain much but throttle response is instant now.

_________________
4g61t.org
4g61t.com

how are the gains from the mod? what other mods do you have on the 1.5l?

Did you port the intake as well? If not, do it! You'll get a lot more out of it! You can get a spare manifold from the salvage yard for pretty cheap to work on.

_________________
http://members.cardomain.com/socrateez
04' Olds Alero
91' Colt GL hatchback
4g15 12valve 5spd.
4g37 TB, MAF & Injectors. 4g37 ECU
Ported & polished & custom CAI w/K&N filter
5* Cam retard, 7*Ignition advance
2-1/4" catback w/flowmaster muffler
89 GT brake and suspension swap
Lots of little s#@t

are there any tb upgrades for my 8v? I've read through everything on this board without a definate answer.

read everything again i just answered this 2 or 3 days ago...

was that the thing about how the 90 style 1.8 tb fits? my memory is all cracked out..

Unless that stuets84 dude surfaces to tell us what 1.8 he got his perfect-fitting TB off of for his 8v, then this is as difinative of an answer as your gonna get.

_________________
91 Hyundai Excel GS - stepbrother to the CSM
88 Piazza Turbo - Italian-Japanese fusion
88 Isuzu Trooper - 4x4 fun!

Dont use the coolant bypass trick unless you defeat the FAIV. Also, what kind of idle speed control does your car use as stock?

FAIV?

_________________
http://members.cardomain.com/socrateez
04' Olds Alero
91' Colt GL hatchback
4g15 12valve 5spd.
4g37 TB, MAF & Injectors. 4g37 ECU
Ported & polished & custom CAI w/K&N filter
5* Cam retard, 7*Ignition advance
2-1/4" catback w/flowmaster muffler
89 GT brake and suspension swap
Lots of little s#@t

the bypass trick works perfectly, on your tb there is a metal chanel in wich the coolent passes thru to heat up the throttle body to warm the charge of air on cold mornings(ever remember cold starts in old vehicles , well this is why it was invented) well it works a little too well and you have 300f coolant passing thru it its not good for hp(remember cold air coming in is good for hp, cause colder air is denser so theres more o2 per square inch, more o2, more power) those of you in northern states will not like the bypass trick unless you make a choke{more dense air over populates the fuel causing hard starts(my theory anyway)}.anyway the way to bypass it is just to buy more 3/8 tubing for $4.99(yours probly isnt flexable enough)and loop back with 1 peice... thats it , i dunno what that guy was talking about with the watchamajiggy. any more ?'s pm me.-dave

_________________
4g61t.org
4g61t.com

More than likely there are coolant lines running through the lower half of the intake manifold as well. I haven't delved that deep into my 4G15 to really check it out yet, but bypassing that would make a huge difference.

Another great idea to further isolate heat from the intake charge is to use insulator gaskets for the IM anf TB/plenum. You can make your own out of teflon sheet.

You can see a good example of this on the portion of this page under 'Manifold Insulator':
http://www.s2000.org/Trooper/manifold/

Here is some more info on the principle and some data to back it up down near the bottom:
http://www.s2000.org/mods/insulator/

_________________
91 Hyundai Excel GS - stepbrother to the CSM
88 Piazza Turbo - Italian-Japanese fusion
88 Isuzu Trooper - 4x4 fun!

FIAV = Fast Ilde Air Valve
Your theory is right. When the cylinder walls are still cold, the fuel will condense on them, making ignition really hard because the mixture is too lean. That's why the ECU is open-loop when the car is still cold, compensation for the condensed fuel.
Another thing is, you need more air flow to better turn that fuel into a gas when everything is still cold. Exactly that does this FIAV thingy.

_________________
Got rabies?

hrmmm... my car is still hunting for the right settings it likes. Am I going to have to reset my ECU?

_________________
01 Maxima VQ30DE
92 Summit 4g63t (Traded to Evo... R.I.P.)