Went to the track tonight. The new chip was a little better. Old time 17.6 @ 83.0 and new time 17.1 @ 80.0

Gonna try another tweak or two and see if it will come down any more.

 

17.1 Ouch thats no bueno. I guess you need alot of tuning. Hey I was looking in your sig and I noticed that you have hooker super comp headers am I right? Dont those things have 1 3/4 primaries? If so thats probably killing you down low,you dont really need 1 3/4 primaries until you hit somewhere in the high 300 hp range. Just thought I would let you know. Good Luck.

 

Your MPH went down by 3mph though? Do you know why?

 

my stock 305 TBI runs 15.7 on averager (15.6 best)

 

Don't mean to make you feel bad, but why is your car so slow?

 

It may be time for a hgih flow fuel pump and larger injectors. Your car may be very lean up top. I see it a lot with heads and cammed LO3's that run on the stock pump and injectors. You should be low 14's all day long with that combo dialed in right.

 

at least low 14's , according ot the tazzo, i'm running 14.5 on the stock heads.

i think your tune still needs alot of work, do you have any datalog information?

 

mine ran a 15.8 stock, time for a tune up!!!

 

thats not bad, best i ever did bone stock was 15.5 (with tuning), i added a cam and headers to get that mid 14's , but that number is not yet track verified, as soon as i get a dry weekend here, i'll have real times.

 

Love that paint scheme on the side looks good; when I bought mine it was hard to decide purple or red

You need to do some serious tuning there stock back in 95 my car turned a 15.54 – 91 mph you should be deep in the 14 second bracket with those mods

 

I don't know why it is so slow. I have some data that I have logged. I'm hoping tuning will do the trick.


IROC,

Yes I am running the Super Comps. As far as the primaries, I don't know what they are.

Shifty,

Indications from the logs are that I am running rich. I will e-mail you one of the logs when I get home.

 

BronYrAur,

I don't know why I went down 3 mph. It was a different track. Could that make a difference?

 

This is getting frustrating. The first race last night was against a Grand Prix GTP. He ran a 13.3 @ 100mph. In the first race I ran a 17.7 @ 77. I got smoked on that one.

Don't those Grand Prix's have a V6. Are they capable of that kind of time with out help?

 

post your logs, that way we can all see what your computer sees.

running THAT slow, it may not entirely be computer related.

 

I tried posting a log once before and it did not work. How do you do it?

 

There are a couple ways to do it but you could do a "print screen" and save it as an image and just post it like a picture.

 

I'll give it a shot.

 

If they are the super comp 2055's , they have 1 5/8" primaries.

With times that slow, i doubt the chip would be the limiting factor.
Have u done a COMPLETE tuneup? is the cat clogged?

 

Define complete tune-up for me. I'll tell you if it has been done.

The cat is new, only 4 months old. Can it clog that fast? I have been running rich, will that clog it?

 

Still can't post the logs. I can's seem to get the file below 100k.

 

Spark plugs u should really change, or at least check them. u can learn a lot by the condition of your plugs.
If u are running too rich, i definitley think that can clog the cat.
U have a TPI on now correct? Did u change fuel pumps when u swapped over?

 

iroc, i disagree. i went with slp 1 3/4" headers into dual 2 1/2" cats into a 3" cat back. while i only gained 7 peak hp and 8 lbs. ft. torque, i picked up hp AND torque all through the rpm band; there was no bottom end torque loss. with no other tuning, i went from a best of 15.92 to a best of 15.61. i think there's quite a bit more there with fuel pressure adjustments and chip tuning.

when your exhaust is as restrictive as ours are from the cat-back, i don't think the old "big tube headers kill bottom end torque" rule applies. at least, i didn't in my case.

 

Cali,

I have TPI heads, I still have the TBI unit. I did not do a complete change over.

The plugs are less than a year old. O2 sensor is less than a year old. The cap and rotor are less than 4 months old. I think that will about do it.

 

SEANOF30306, I was really going off of an article I saw in a CHP magazine a while back. They test a 350 hp 383 with cast iron manifolds,1 5/8 headers and 1 3/4 headers. The 1 5/8 showed more gains from idle to 5000 rpm and the 1 3/4 showed more hp in the upper RPM range. The 1 3/4 still gained like 10 hp and tq over the manifolds but the 1 5/8 showed more gains in the low end and through the powerband. I guess it does matter thow what you have after the headers. And although you didnt seem to gain much hp or tq you gained like one tenth less than I did when I was in my headers and exhuast so I guess it cant be all that bad. Still the CHP guys made it sound like a terrible Idea to put 1 3/4 headers on a motor with less than 400 hp. Im glad to see yours turned out well though.

 

I was reading a book written by John Ligenfelter (sorry if i mispelled that) where he said that a 305 should have 1 1/2" headers until 400HP, where it should then be 1 5/8"

So yes, I would think that they his headers are just a little to big

 

i've heard that 1 3/4 headers were too big for engines making less than 300+ hp for years, too. there are two things here, though.

first, even a 3" cat back only flows as much as a standard 2 1/4" dual setup. imagine taking a 69 camaro, putting headers on it, but staying with the stock dual exhaust. that's the biggest restriction we have.

second, i WANTED to limit bottom end torque somewhat. i want my car to be a dual-purpose daily driver. one that handles as well as runs quickly in the 1/4 mile. i'm only interested in running the car with the same setup i drive it with every day. with those limitations, too much torque simply means wheelspin. i'm currently running a set of michelin pilots on the stock 16" rims. the best 60' time i've gotten so far is 2.29; i average 2.3 to 2.4. that's probably the best i'm going to get with those tires. i have a set of 17 x 9.5 4th gen firehawk rims and will switch to them with suitable tires when i've worn the pilots out. that'll help with the current setup, but i'll lose it again with the heads and cam i intend to use. i will always have to be careful about not getting too much low end torque.

 

more on big tube vs small tube and placing the powe where you want it.

20 years ago, i had a 70 chevelle with a 400 sbc, turbo 350 and 3.31 gears. the 400 had dish pistons 350/300hp heads, stock hei, a comp cams 268h hydraulic cam, gm dual plane aluminum intake, carter thermo-quad carb and 1 5/8" headers. it ran 13.80s to 14.0s, but i thought it should do better. lots of wheelspin and not much big end power with the small cam.

we were all pretty serious street racers who'd moved to the local drag strip for grudge night. if you uncorked your headers, used slicks or even mickey thompson dot drag tires you couldn't get a run, so it was critical that the car run well with the L-60 x 15 grand am radials and the mufflers up.

a friend who'd been street racing for years told me i needed to build big end and cut bottom end. first we put in a .510 lift, 260 @.050 duration cam on a 110 degree center. the idea was to use all that duration to cut some bottom end torque. besides, that cam sounded AWESOME! we also went to a weiand single plane intake, a holley 780 vacuum secondary carb and headers with1 3/4" primaries.

the change was amazing. the car launched so hard you could hear the clutches in the posi unit chattering and made huge power on the top end. after changing to a 750 double pumper and getting it dialed-in, we got a best of 12.42 on horsepower; with a 250 horse nos unit we got 11.60s.

a little moose juice on the tires, flash the 3 bolt vette converter to 1500 or so and i could hit the nitrous from the gate.

the car was my daily driver. it had more than enough low end to be fun to drive around town and, after i switched to a ls-1 vette pop off valve, the brakes worked fine, too.

the conclusion to this long-winded story is there's more to making a street car fast than peak horsepower and torque numbers. if you have a car with traction limitations, you have to be careful where you make your power. smoky burnouts may look cool, but they don't go anywhere.

 

Yes they are V6's, and yes, they are friggin' quick. That one must have had SOME work done to it, cuz' stock they run a 14.01. And they already do have a lil' help, they come stock supercharged!
:werd:

And yeah, you should be able to kick my butt bigtime. I got a 15.3 out of a stock LO3 (well, with flowmasters) and when you get done I know your gonna make me look silly...

Bruce (90RS305)

 

i bet ya $10 you or your auto is shifting too soon.


yank it down to first, and manually shift the car.. thats good for .3 right there when stock.

then bring the RPMs PAST redline.... your tach is off..... if you want to know how far off, look at winALDL.... or log a run... then look at your max RPM.




you're probly getting short shifted by the auto, or shifting it too early yourself.

 

We'll find out a lil' more tonight, I'm meeting Bill down at the dragstrip in about an hour and we're gonna get some runs in. Guess its a good thing I waited to run my car until it hit 90*+ outside!!

Yeah 17.XX's!!

Bruce (90RS305)

 

90*'s don't count there. There isn't any humidity.....

 

Hows about a shift kit?

 

I wish my car felt the same way!

Actually, I did get a best E.T. tonight of 15.94!! I was absolutly suprised, I thought I was gonna run a lot worse than that! Can't wait till I actually get some tires that give me even a lil' bit more traction and my ram air hood, that'll do my some major wonders.


Bruce (90RS305)

 

Sounds like my car after I did the cam swap. Step on the gas and the car would bearly even move. Id be willing to bet that the engine is either going lean from an ailing pump, drowning in fuel due to the tuning, or/and suffering from serious timing issues. What do the data logs show? The stock 02 wont tell all but if the fueling is way off itll show it. If it also has alot of knock counts thatll slow oyu down as well. Takes a few seconds to get the timing back after some knock counts have occured. May sound like a broken record but you really need to get the equipment to burn proms. Sounds like the tuner is still way off with the calibration

Chip tuning can do wonders. Well, almost. Cant make my motor pull above 4000 RPM and make power but it sure does have alot of torque. Even with the 2.77s at WOT it slams so hard that it locks the seatbelt and snaps my head back. No matter how many times I do that ill never get tired of it.

 

how much fuel pressure are you running?
Did you jack the timming up, its way lazy in the stock LO3 bin.
Add at least 4* to the whole chart, and add a little more to the PE spark table.
You say its running rich, Have you corrected your VE table so that you are close to 128 for your BLMs? You need to have your VE table right before you can tune your PE.

 

Can the v-6 do that? Yup it can! The GTP has a supercharged V-6 rated at 260hp net. The real plus is the torque, thats what get's you going. A friend let me drive his and it took me back to the early 70's the first time I touched the gas pedal, and I didn't even have it on the floor yet! Maybe you need to study your competition a little more closely, saves alot of embarassment!

 

When I rode in it, it felt like one of the following things:

1) No timing at all
2) No compression
3) Valves Lashed WAY too tightly
4) ...strangely no power


It's wierd, because the engine runs SOO smooth that it doesn't seem like it has a problem at all! Bill, have you checked the casting number on the heads? If they're 350 heads in reality, you may have lost a significant amount of compression. I'm a little miffed as to what to look for on the car. When I was running 17's, it was on like 6 cylinders because my plugs are all fouled, but the car was running really rough, as opposed to how smooth your car is.

I think, the first thing to do would be to advance the base timing little by little and see what that does, and to run the casting numbers on the heads. Also have Chris kind of lay out how exactly he lashed the valves.

Good luck man
Tony

 

Car and driver says those GTPs run low 15.3's, now I know there times are always a little slower but I searisly doubt they are that fast not to mention I used to spank my friend in his moms GTP. They are low 15 sec to high 14 sec cars although there is a kit out there that changes the heads, intake,chip, and adds 5 psi of boost to the supercharger that adds like 125 hp so I am sure they can be made low 13 second cars.

 

I have checked the numbers on the heads and they are 416's. I checked it before they went on.

I e-mailed my datalogs to Dewey and he said I am running way to rich.

 

if you get a chance, i would recheck mechanical stuff, reset the lash, re-time it, ect.

 

Sounds like its drowning in fuel. Need to relay that to whoever is doing your custom chip.

As for the lash, try setting it with the motor up to operating temp and running. Granted its messy as hell, but it gives the best results

 

i dont have much comment on the topic at hand b/c i dont know enough about the subject, but if you send me your data logs through aim or msn as a jpeg or gif or w/e i can shrink them for you and post them up. my aim is dougieG85, just hit me up and i will get em posted asap

 

dont mean to jack your post but im going to be doing the same thing i got the following done

hedman headers 1/58 flowmaster muffler stock tail pipe
and i got 97 tran LT1 cam and 416 heads with 1.94 intake and i think 1.64 or 1.60 ext.and im either gonna port the stock intake or just leave it on cuz i got no money for the edelbrock intake.do i have to get a different fuel pump or can i just keep the stock one.also i only have 13 lifters from the lt1 cam with only 20k miles but my car has 120 thousand should or can i reuse my old ones or should i get new ones.also where can i find used ones with low miles cuz i aint got much money left

 

Just re-use your stock lifters. I would change out your fuel pump whenever you get the chance. It is hard to dial in a heads and cammed LO3 with the stock pump. You do not want to run lean with your new combo. With those mods you will need 15psi+ at WOT and the stock pump will not support that.

 

thanks for the reply also when i get the pump what should i get i plan to do more to the 305 tbi also what do you think ill be running with that set up and 3.73's with a posi and a 25-2700 stall and a shift kit so i can shift manually.

 

arg... let me try somethin else

working on getting these logs posted

try to get them from this ftp tell me if it doesn't work

these should be on there within the hour, it's 12 on sunday

 

ok they are up they are under the data folder, both data and data 2. oh and on a side note please dont mess with this persons FTP he is a good friend of mine and i would really hate to see something i asked him to do mess up his ftp... i know none of you will but somebody that lurks might, so please just be respectful. thanks

 

Looks like the car is too rich and has detonation under WOT. From the map readings it looks like a larger tbi wouldnt hurt, either.

 

So waht would you suggest I do to get the running better?

 

One of the first things to do would be to trim the fuel. Its rich at WOT but you also have to be careful that its not too lean. Ideally youd want AFRs hovering around 12.5:1 or so but that would nuke the cat. The stock calibration calls for an AFR of around 11.5:1 at peak torque but its going to be difficult to get that off of the stock 02. Youd also want to change the spark advance tables.

For the part throttle stuff, which is every bit as important as the WOT stuff, youd again want to trim the fuel and get the spark tables in line. Unfortunatly, the part throttle tuning is mostly by feel. You set the SA to what makes the car perform smoothly, have crisp throttle response, and not have any detonation. This cannot be convayed through a data log and youd ultimatly have to do it yourself.

First things first, though, get your datalogs out to your tuner and tell him that its really rich and it has detonation in certain places. Also save your blm and knock tables in WinALDL and get those out to him as well. Finally, tell him any issues that you may have noticed with the car. That should at least get teh ball rolling on the tuning.