gator's 99TA

iTrader: (2)

Well i just wanted to get some opinions on this site from people who run BIG cams in an auto. i have ls1edit tuning from a guy i have full confidence in, but wanted different opinions. i run a comp xe 230/230 .574 111 LSA cam on stock heads and an auto with a yank st-4000 convertor. at this point, we have gone around the world to get it to idle well. in Park and Neutral it is perfect once it finds itself, usually only taking a few moments. i am real happy with it. in Gear, under load, it surged like a **** when warmed up. the idle is already set at 1000 rpms and a plenty big hole in the tb.

the car is basically a daily driver and when it surges it goes up to 1300 rpms sometimes and pushes the car if i am not on the brake hard! honestly it is crazy. i also dont want the IAC so high i am driving around at 2K rpms at 30 mph (like an cruise control!).

what my question is, is this the best i can hope for with a big cam and auto loaded? again the idle is great in park, just surges BIG time after TONS of programing time. is there anything i can do? i would post this in computer section, but i am mainly asking the big cam guys if they get surging that pushes the car? i love the way it performs all the way to 6900 rpms, but i think i could live without the headaches.

<small>[ February 15, 2003, 11:07 PM: Message edited by: gator's 99TA ]</small>

v8 ute

I have TR230 cam which is on a 110.6 LSA, Ported heads, bolt ons, Vig 3200 and 3.73 gears.
No it's not too big.
Mine idles @ 900rpm in neutral and 850 rpm in gear.
I have 84mm TB with a small hole drilled in it.

Mine surges sometimes but not like yours.

I can only think you have more programming to do.

RPM WS6

iTrader: (3)

Hmmm...

If it is surging only under load perhaps there is too much timing? Too much extra timing can make it idle great under no load but really make it hunt under load.

TA2SLOW346

iTrader: (3)

I would just unplug the IAC and be done with it.

gator's 99TA

iTrader: (2)

ta2slow, is that what you did to get your TA running so smoothly?

also the TR230 cam is very different i believe. with that low exhaust duration versus my 230 exhaust duration i think it makes a big difference. i am running a total of 30 degrees of time i believe.

Ragtop 99

iTrader: (7)

At a certain point, there is nothing you can do about cam surge. Ask the M6 guys and you'll see that they don't drive at 1200 - 1300 rpm in their cars if they have 230 cams. I have a 232/236 114 and the surge bothers me at 1300 rpm too. Adding air gets rid of the surge but causes a cruise control effect that makes the car want to pull along at 1400 rpm. If you want to keep the cam the following steps can help make it more livable:

1) cut back the air from where you are. You need more than stock but it sounds like you have too much.
2) add a little extra timing
3) raise your part throttle shift points a bit.
4) raise your lock up speed (and unlock speeds) in 3rd and 4th gear at the 0% and 6% settings.

While this helps, I'm stepping back to a 228/228 114 XE-R cam.

More programming help is available in the computer forum. here is a good start:

https://ls1tech.com/ubb/ultimatebb.p...=003892#000000

rich

with the car in neutral rev it up. Does it come right back to idle? Or does it take a while to find idle? (hang up around 1500 to 1800 rpm's) if it is hanging up the hole is too big.

gator's 99TA

iTrader: (2)

so unplug the IAC sensor and leave it hanging off the lid? what will that do?

and upon initial startup it will stumble real bad in this cold weather but will find its idle and be great. if i rev it it rarely will stuble and die. this is all in park. in gear, it is a totally different story. it doesnt hang at all at this point. there is no "cruise control" effect.

gator's 99TA

iTrader: (2)

ok more info, it only surges when it is on a hot restart and at a stop light (warmed up). that info might be pretty good to others out there. i will try the !IAC off the TB as others have suggested. who knows. it might work.

TA2SLOW346

iTrader: (3)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by gator's 99TA:
<strong> ta2slow, is that what you did to get your TA running so smoothly?

also the TR230 cam is very different i believe. with that low exhaust duration versus my 230 exhaust duration i think it makes a big difference. i am running a total of 30 degrees of time i believe. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Yes my car ran very smoothly,no surge or stumbles. You can take my advice or not, its up to you.

TA2SLOW346

iTrader: (3)

What I did was i started the car and when it was at 1000 rpms i unplugged the IAC and the car would always idle at 1000 rpms.
The only draw back to having the IAC unplugged is you have to give it a little gas on cold start ups. I had to hold the rpms up to 1300-1500 for about a minute to warm the motor up then it idled great.
good luck,
Shawn

StevieZ

iTrader: (3)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by TA2SLOW346:
<strong> What I did was i started the car and when it was at 1000 rpms i unplugged the IAC and the car would always idle at 1000 rpms.
The only draw back to having the IAC unplugged is you have to give it a little gas on cold start ups. I had to hold the rpms up to 1300-1500 for about a minute to warm the motor up then it idled great.
good luck,
Shawn </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Here's an idea. Hook up a switch to the IAC and flip it on for cold startups. Shut it once the motor has warmed up. Something like an "electronic choke"

<small>[ February 17, 2003, 07:11 AM: Message edited by: StevieZ ]</small>

Dave Carney

I think that cam in an auto is an exercise in frustration. It may take a week or two or a month or some real cold weather, or a sudden stop, but eventually it's just going to pi$$ you off enough to take it out. Before you do though, take it to the track and get on the '03 list <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />


PS: I thought you were now in the kinder...gentler street car mode <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />

<small>[ February 17, 2003, 08:03 AM: Message edited by: Dave Carney ]</small>

ROB'S SS

im glad i dont have those problems with mine. i have a 230/228,591/588,111 +4*. if i lock up at a low rpm it will shudder. but i can unlock it whenever i want so no problem there. i do have to give it gas everytime i start the car, but only for a few seconds and it will idle fine after that. no dieing if i hit the brakes real hard, and only sometimes will it die if i hit the gas quick and let off in first gear. i have my tb hole drilled out to almost 1/4" and my iac's are still a tad bit high. normally around 50-70. before i drilled, they were around 120-130 no load.

gator's 99TA

iTrader: (2)

well here it the verdict. i have made two major changes in the past 24 hours with this car. i put on a set of hooker LT headers as i was REALLY sick of the header leaking and ticking from the collectors. it was pure black around the primaries into the collector. i have a feeling oxygen MIGHT have seeped into the area and messed with the O2 sensor. secondly, i did the GHETTO MOD of getting my car to idle at 1000 (normal for me) and then pulling the IAC sensor at the TB. well, for the life of me i cant understand how this works, but **** my idle is now friggin PERFECT. now just like ta2slow said, under cold weather starts, like it is today in the 30s-40 degrees, it takes a few seconds of foot idling to keep its idle. then it just sits perfect at my set idle. i dont know what to think of this but it works for now. no stumble when slowing down, no surging at all, no "cruise control" effect, etc. i am sure there is a way to do this with Edit, but this manual way of !IAC sensor is working. i drove it around town today (usually the tough part) for about 25 mintues and will continue to give feedback on this ghetto mod.

- team rigged and jimmed......props on the mod <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

Pro Stock John

iTrader: (34)

Like TA2slow side, you can just unplug the IAC.

You can do that any time if you like how the car is idling.

Next time you plug it back in you might need to reset it.

Your cam is on the big side for a stock bottom end so it will have warts.

gator's 99TA

iTrader: (2)

will cold or warm weather effect the cold start-ups?

TA2SLOW346

iTrader: (3)

Gator it will be about the same all the time no matter what the weather is outside. You might have to hold the RPMs alittle longer in the winter til the engine heats up, but after that your good to go <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />

firebirdls1us

Ta2slow,
Is your car an a-4 or m6 because I also unplugged the iac and the car idles fine but I wonder will there be problems with a-4 tranny down the line?Because the ses light I can deal with but the tranny is another thing.

Silvr98z28

Mine did the same thing until I put epoxy over the hole in the throttle body that was too big and then slightly enlarged the hole that is alreade there. Now only surges until it warms.