I have a 87 camaro 2.8-->3.4 with a hypertech chip, flowmaster catback, and unfortunately a 700R4. i took it to a track over the summer and my times were very disappointing, just below 18s. Does anyone have any idea why i got these times? I get 'the rich' code once in a while and was wondering what to do about it. I heard about somethign you can do to those cookie shaped things on the exhaust manifolds to help the exhaust flow. Does anyone know how I wouyld correct this problem?

I thought about a T5 but a few deals fell through so thats on hold till i find another cheap tranny.

Any help guys?

 

Well first off, what's your trap speed? Mileage? Elevation of where you live? We need a few more details.

 

Fastest I have ever seen in my 3.1 is 17.5 all stock. I haven't been since the flowmaster muffler upgrade, but I doubt it does a thing, as well as my hypertech chip... I'm sure that does nothing at all.

Almost need a turbo to just get our cars as fast as a civic...

 

A well tuned 3.1 will do a high 16 second run, 2.8 cars will run a few tenths slower.

My wife's '91 3.1 RS with automatic, 3.23 gears, and a stone stock 195,000 mile motor with an occcasional undetermined knock ran a 10.84 1/8th mile with a passenger.

This was at sea level, low 70's ambient temparature and 80 percent humidity.

We don't have a 1/4 mile track near us but the accepted conversion factor is to multiply the 1/8 mile ET by 1.56, and doing that I came up with a 16.91 quarter mile ET.

If you are running 18 plus with a 3.4 longblock then something is robbing you of power along the line.

Eric

 

slush box, you need to built it and get the corvette servo n other parts. Really any easy job just messy.

 

don't know how much the vette servo helps as far as performance goes (that is 1/4 mile time). My ole slushy is built, vette servo, mild transgo kit, and a larger boost valve, the car will damn near break ur neck into second gear, and is firm into third, but i still was running 17.8's at the track on my 2.8, at the time the engine was running crappy anyway, but i highly doubt it'd do much better than that, even now....sux majorly. This was on a jasper 2.8L that was 1.5 years old, the engine is now 3 years old, and running, but not good due to ignition issues out the ***...The good thing on the built tranny, chripin second gear, bad thing about it, chirping second at the track normally isn't a chirp, it's a whizzin sound as ur open differential gets no traction after the 1-2 shift.

 

Well im not sure what trap speed is, but my reaction times were around .2-.4 and the elevation is somewhat high where the track is. The engine is a 3.4 with about 100k on it and hasnt been tuned up in about 2 yrs but the car is not run in the winter. Is there anythign else u guys con think of that would be robbing my horsepower?

 

If you get an occasional rich code, you probably just need a new O2 sensor. Although in my experience a bad O2 will usually say 'lean', even when it's rich.

Give it a good tuneup and you should see better times.

 

Wow since i got the rs v8 havent been on here much but was seeing if the guy who bought my bird was on here. Dont feel bad man my 2.8 did 20.8 at elevation so in reality we lined ours up and its not that disapiointing. I definately vote for o2 sensor plugs wires cap rotor and throw a blaster coil and good module at it and see what she does.

 

What times are the 3.4 conversions running when properly tuned? I would think at least mid 16's.... My 2.8 is running right at 17 now (finally ran it). I was pretty dissappointed myself. Oh well, I'm looking into either a buildup or a 3.4 (if you want one I can get you the hook up).

 

Do you have your time slip handy? Trap speed is down at the bottom

Reaction time doens't mean anything in this case, the time won't start until you leave the line.

 

I wonder if it would take a turbo to get a 3.1 litre down to 15 seconds... and still retain some fuel economy...

 

What about other factors, like weight of car (got a stereo system with a heavy box?), mileage, last compression test readings, etc..?

I ran a 16.87 in the 1/4 back in 1996, with the car running in crap condition, with only a dynomax super turbo exhaust on it. I restored the car in '97, when a ton of go-fast parts went on. Every run after that restoration has been in the low 17's... best was a 17.1 after installing a TCC lockup switch.

So all I can figure is that with all the miles on the motor, the engine's just tired out, and needs a rebuild.

 

Tom, what about the tranny? Maybe you're slipping it.... I know my times are seriously slower than they should be...I'm losing 6mph in the trap, and it's all through the tranny. But you still can't feel it slip at WOT...but it does.

 

At the time I ran the car at the track, I took everything out of the trunk. I did not feel any tire slip but when my tranny was shifting into second, it kind of glided into it. I noticed it does it under very heavy acceleration. I know this contributes to it a lot and I actually just bought a T5 but is there anyway to get the tranny to stop doing this?

 

"Gliding into second" is tranny slip.

There are a few cheap/freebie ways to get it to stop slipping AS MUCH that I've had success with.

You can up the pressure at the TV cable on the throttlebody. Higher line pressure will push the clutches together with more force and hold them stronger when in gear under heavy load. But too much pressure and you can blow seals or start losing fluid past seals.

LUCAS SLIP FIX. The stuff is liquid gold. Add a full bottle...they say 1 bottle overfill is fine, so you shouldnt have to drain any fluid to add it. The stuff is thick as hell and you should feel a noticeable increase immediately. After I added a bottle, mine would chirp second like it used to for about another month til it really started to burn up.

 

Yep. 2nd should not glide into gear. It should snap into gear and jerk you about. GM trannies shift hard or should.

I know some Fords are made to slip or glide. Ford trucks do that. Ive driven a few from old [80s] to new[90s] and they glide into gear. Feels funny.


If you are gonna get a new TC get a switch pitch TC. It will launch at 3000-3500 then the rest of the gear its 1500-2000.

 

Heh, mine has been gliding into all gears for the past year and a half now. As time would have it, it was nice out today so I took her out, punched it on a straitaway and then suddengly going about 70, it wouldn't shift from 2nd into third, until I let off the gas, and about 10 seconds later if shifted. As of now, it would rev up in overdrive on the freeway from about 2200rpm's - 3300rpm's when you barly tap on the gas. Heh. Go figure. Got her home, locked in the garage till I decide on what to do with the trans.

As for how much you guys would hate it, I've been pondering getting a B&M 700R4 for a 90* engine *hint hint*. No emissions where I live, so what the heck. Yet, if anyone has any suggestions on the current trans set up, let me know

-Dan

 

The first time I did the 16.87, the trans blew a month later. My current trans is still acting up- if I'm driving normally, and leave a stop sign with the stick in OD, the trans will slip in 2nd gear. If I shift it automatically, the increased line pressure prevents the slip. I don't think the guy that rebuilt it used the proper length 2/4 band apply piston. But there's no slip in 3rd gear (or first), which uses clutches.

So even though the trans is a piece, I don't think it was affecting my latest times. Even so, you'd think I'd be equalling my original 16.87 which was run with a bad trans!

 

It's a common problem (no 2-3 upshift at WOT); the only fix for which is a rebuild. My original trans did that since I got the car in '94, and that trans (the 16.87 1/4 mile one) died in 1996. So you've got at least two years left. It's been posted many times in the transmission forum, but I don't think anybody knows what causes it (other than general wear).

 

He did mention that the elevation was "somewhat high" where he is....

Need to know the elevation to correct it to sea level and find out how truly slow you are or not.

Eric

 

Eh, well except that the tcc isn't locking at all in overdrive anymore. All it does is slip. So I don't like driving it down the freeway in overdrive anymore due to the reving it likes to do

-Dan

 

Brings back old nightmares.. that was my 700R4's death knell. Lost 2nd completely within months. Funny thing is, I still had 4th. Never did quite figure out what happened.

 

I had a feeling there was something wrong with the tranny but I had it rebuilt only about 25000 miles ago. I know that doesnt mean all that much but is it possible that it could be the torque converter slipping? I know my Tc is on its way out so maybe its slipping when the TC is engagign or w/e. Just a thought.

If elevation is so important I'll find out the exact elevation for the track.

 

"torque converter slipping"....lmao...

I'm sorry man, I'm not ragging on you... All torque converters slip by virtue of design. That's how you can slow down without stalling. Inside a converter is two turbines...one on the engine side, and one on the transmission side. The engine side spins with the engine, naturally....and spins the tranny fluid inside the converter. When you get up to a certain rpm, the fluid spins with enough force that it spins the transmission turbine on the otherside. The two are 'fluidically coupled'....

The torque converter lockup PHYSICALLY links the two sides together, so there is no fluidic coupling between them anymore..it's a solid connection. That's why the converter doesn't stay locked all the time...it would cause a lot of problems (although converters CANNOT physically lock in first gear).

I find it pretty unlikely that the converter clutch itself would slip....since it's a simple solenoid....it's either on or off. HOWEVER, things like a faulty vehicle speed sensor, etc. can cause the car to KICK the torque converter in and out of lockup. When the rpms go down, it's in lockup. When they go back up, it's back in fluid coupling.

You can wire a switch into your diagnostic port to MANUALLY lock the torque converter. This will keep the rpms from bouncing around if yours likes to jump. Mine did the same thing and the switch is nice, AS LONG as you remember to turn it off when you decelerate below 40 mph or so , or accelerate more than a SLIGHT tip in of the throttle.

The link on how to make a lockup switch is here: https://www.thirdgen.org/newdesign/t...ueswitch.shtml

 

I know how a torque converter works but like I said, mine's shot. It does like to 'jump around' and I already wired up a lockup switch for it. Im in the process of converting to a T5 so I guess it doesnt really matter.....thanks for the help tho

 

91 3.1rs,5spd.,3.42gears,underdrive pulleys,air box from a tpi car with k&ns,2.00 60',15.88@85mph at H.R.P. 15'above sea level...

 

Whee, having it rebuilt with a corvette servo and a transgo shift kit. The guy at the shop told me he did that anyway. Whoo.

What's really funny is that when I went to the trans shop today to get a quote just to find out, I was on my way out, jumped in the jeep. Pushed the clutch in.. and "Uhh, where's the pedal pressure?" Either the slave cylinder or the master cylinder has gone. Funny thing is, right on front of a trans shop, go figure.

-Dan