Ok,

I have '89 Formula 350, only mods are K&N Filter, MAF screens removed, and SLP Runners. (No the pleneum is not ported, its just the way I bought it...)

The car just doesn't seem to get off the line quick....once it starts moving it goes pretty well. I have been reading some of the posts and most people seem to get a good kick off the line, easily inducing wheel spin (I am running 245s), saying things like "good torque" etc.

Sometimes I can get the tires to spin, usually I can't. Trying to figure out why? The engine runs pretty good after its rolling, but no jump off the line.

BTW I don't know what rear end it has (its stock based on the rusted tag and diff cover)..

Is something wrong or just my expectations?

(Air and Fuel filters new/cleaned)..

 

Done a good full tuneup lately? Is the cat clean, could be clogged. I have a 305 tpi and when i got it, it was like what your describing. When i did a full tuneup and put the whole new exhaust on with a 2.73 open rear it spins them pretty good off the line everytime, if i want it to

 

Ok...I forgot...to add it has a Ravin Cat back exhaust...but the cat looks stock..
I have an exhaust leak in front of the cat..so while I am down there..I am gonna take it off and look at it...

Is there a way to clean the cat? (vs. shelling out $$$ for a new hi flow model?)
I don't have headers yet, maybe when I do those I will get a new cat...or just delete it...

I have done the tune up except for spark plugs...replaced the filters, replaced all the fluids etc...spark plugs probably this weekend...

 

First, a tune up may do wonders. I have a 1989 GTA 350TPI auto with minor bolt-ons and always spins from dead stop. When it wouldn't launch as hard, it needed a tune up: spark plugs, spark plug wires, fuel filter, air filter, distributor cap & rotor. You should have the 3.27 posi rear like mine. According to previous post on SLP Runners, the plenum should be ported and gasket-matched. Otherwise your SLP Runners is likely hurting performance instead of helping. It's also recommended to port the intake manifold or replace with an aftermarket brand i.e. Edelbrock to benefit the 15-20 horsepower as SLP claims on their Runners.

My minor mods are:
SLP Runners/Ported Plenum
SLP air foil/Screenless MAF
JET CHIP STAGE II w/180 stat
March Power Amp Pulleys
Throttle Body Bypassed
Timing set @ 8 degrees

 

There should be some RPO codes in your glovebox too.

 

something is wrong here. hell my now 120K iroc with 350 A4, 2.77's will spin the tires into oblivillion. tune/ check the cat would be a good start.

 

Do a full tune up.

 

check timing, tune up, vacuum leaks, or could be your trans isnt downshifting when you hit it... or is this from a dead stop? TPI is known for out of the whole performance. Hum... hope you fix it... could be the plugs coverd in carbon and crap... never know.

 

Planning on doing a tune up this weekend I will post results so hopefully others may benefit.

Thanks for your responses.

I don't have my RFO codes, a previous owner removed the sticker! I did get the factory build sheet from PHS., which didn't specify any axle options, just the Formula 350 package....several websites listed different ratios for '89 Formula 350s...Any way to get a listing or repro of the RPO sticker?

One other thing that may be related..the engine runs way better when its cold (duh!), but the tranny shifts firm when first driven for the day..then gets softer after that...The engine runs too hot IMHO, not out of GM spec mind you, but still 195-210 seems to warm for good performance...I plan on adding a lower thermostat and changing the fan on temp via DIY-PROM. Maybe once I get my ALDL cable I might have more info to work with.

 

yea, just dont do what i did and strip the tstat bolts... they are easy to do... a lot easier then you think... 3 helicoils and about 2 lbs of RTV sealant later... it still leaks... oh well. It leaked before.. so im not all tha worried.. but the 170 stat i got is from GM. Look at Willie's fan control and he gives the part number... actualy.. if i look around my desk, ill see if i can get the number for ya. Its cheaper on line, but shipping kills ya. Better off going to a dealer and seeing if they have it. Its cheaper then the ones jegs or summit sells I got it for 4.30 + 7.50 in shipping... it said at dealer its 6.50. I have ran cool and only get near 220 if i sit in traffic for more then 20 mins on a hot day.. but driving.. it doesnt get near the mark between the 100 to the 220 mark.

 

Depending on your pipe size a dynomax super converter runs 55-65 dollars goto www.dynomax.com and look up your application.

 

lol what have u guys done to your guys 305s unlesss u mean ur holding the brake cause mine cant spin them off the line hardly at all.

 

try launching in 2nd gear... hehehe hold on to your hats...

 

If the engine is stock the SLP runners are hurting your low end, but shouldn't hurt it that much. It is definately noticable on my car when I put the Edelbrock runners on. But I have way too much low end as it is and I have a cam in it. You might have a modifed engine with a cam in it and tall gears with no stall converter. if you have an exhaust leak in front of the CAT it's a good sign that the CAT is plugged. That will kill lots of power!!!!

 

i've got a 350 not a 305. no power braking necessary.

 

got a 305 not a 350... no power breaking necessary.

 

yeah I get some pretty nice one-wheeled burnouts, but that's about to change quickly - 4.10 posi in this weekend!!

 

trade the peg leg for lower gas milage!! but in this world.. who cares..

 

I don't really want 4.10's but for 200 bucks and an eaton posi it's better then the really noisy rear that's in there now. And I drive a Camaro, if I wanted gas mileage I'd get some ****, like that would ever happen

 

a



hehehe hell yea... but i do enjoy the 24mpg i get in my car...

 

yeah right now i get 23.4 highway it's great but i drive all city so it usually sucks anyway 4.10's should be fun light to light tho

 

I've gotten 24.5 with my 350. My rear end has a 3.42 Richmond gear set and an Auburn Gear limited slip unit........ BTW, if you are running an automatic you might not want to go below 3.73, they have a really low first gear to begin with.

When my car had a 305 in it, it would still leave about 15 feet of rubber with both tires (with cheapo T/A radials).....

 

if you try all this and it dosent help, if the overrunning clutch in the stator inside the torque converter fails and freewheels in both directions, you will have poor low speed/off idle/take-off performance

the fix is a new convvertor, what better time for a stall convertor??

 

yes sir i had that same exact problem with the 200-4r in my olds. a new convertor and the tire was spinning relentlessly.

 

Argh!

Changed the plugs(wires are aftermarket 8mm hi temp radio suppression)...removed the AC 2 (Rapidfires)..they looked fairly old one was rusted in (it broke coming out...but I got it out)...way easier from under the car.
The gap was huge..I guess probably something like 0.060-0.080 (guessing since it was way bigger than my gap tool at 0.045.)
I guess that's the good news.

Bad News...doesn't seem to drive much different, feels better in the mid ranges. I did disconnect the battery cable during the change....so the ECM should relearn. Still kind bogs out of the hole...once the R's climb it moves pretty well...just like before..in fact I am not sure that I can tell the difference...it does feel smoother though.

Worse news: My temperature gauge stopped working. It cycles on startup and then stays pegged at 100 degrees..I know the engine was hot enough to make the needle move...
Anyone have any ideas what happened? Did I bump a sensor?

(I know I could have taken it and had someone change the plugs..but still it was a satisfying feeling doing it myself even if it took like 4-4.5 hours (the busted one took quite a bit of coaxing, and learning contortion with a rachet.)

 

Ok..after reading more...I probably whacked the sensor...its still hooked up..but it was #3 plug that was fubar'd so I'd say either the wire is loose or damaged or the sensor is bad...ick. At least its a cheap part.

 

sounding more and more like your torque convertor

 

Yep I am beginning to agree...

How would I check that? (Without taking the Tranny out).

One thing..the tranny shifts firmly when its cold...after it warms up..I seem to lose the firm shifts and the hole power. This leads me to think it is the tranny...

If I am gonna replace the converter...definately go stall (what RPM? 2200-2500 I am thinking), but I might as well get the whole thing rebuilt.

Any idea how much that would cost..(its been a while since I have had to have a trans rebuilt). Converter prices are easy enough to find...I am guessing I am probably looking at $600-$800 bucks right?

Dave, any good shops in Downriver that you'd recommend?

 

from what i remember a 700 rebuild is near 1200 to 1400 for a good rebuild. You might be better off just getting one from TCI, B&M or another trans company. You can also order a good 2500-2800 stall from them too. the tc's are usualy int he 300-400 range. teh 600-800 ones are for the 4l60E's.

 

I did find out my TV cable wasn't adjusted properly...that seemed to make a difference out of the hole.... I followed the procedure at http://www.tvmadeez.com/article/ ...

Now I just need to find a way to keep the tranny cool...I think I am gonna start with a lower thermostat and custom prom (fan on).. Any recommendations? I was thinking 160 stat and fan on about 180?

 

the best thing you can do to cool your tranny is an external tranny cooler, That way the oil in the tranny doesnt have to compete with the other fluids in the radiator