Your thoughts on my slow car

[T-top87GN]

Well, first off I would like to say I had a great time at the BPG Nats. It was a professional show and as always I just had a good time seeing old friends and making new ones!

This may well be a long post, so please skip reading this if you need to use the bathroom or if you have a short attention span.

Lets see, 2 years ago my car was stock with only mods being a chip, a 3"dp, orange stripe, and a set of blue tops. The best it ever ran was a 13.0something at around 100 with 20psi on pump gas and alky. I started my upgrade path basically just buying whatever I could get my hands on that was cheap and tha I could use. I evetually put on a PT-51 and 55 lb. injs. Then my car was wrecked. The say the car was wrecked my Mark Jackson IC came in via UPS. Now fast forward.....

I have the car back together. Now I am running a PT-51, 55 lb. injs, Mark Jackson IC 17 row, orange stripe, and 3"dp. With 20psi and 114 race gas the car ran guess what? 13.0.something at around 100. WTF?!

The only thing I can think of is that 3rd gear in the tranny is slipping. I mena that's really the only thing I can think of...

Am I barking up the wrong tree?

I'm going to post this on t6p.com and bpgforums.com as well.

 

[T-top87GN]

Oh I forgot to add, DirectScan shows O2's in the 760-770 range. So apprently, the motor is using all of the fuel I am throwing at it.

 

[BLACK6PACK]

The problem is that you're running the same boost. You ran 13 something @ 20 psi and now you're running 13 something at 20 psi. Sounds logical to me. If you're going to run 114 octane get a chip to take advantage of the octane and turn the boost up to 25 psi.

The stock turbo is done at 21psi, the 51 you have now will wake up after you turn the boost up.

 

[T-top87GN]

Originally posted by BLACK6PACK
The problem is that you're running the same boost. You ran 13 something @ 20 psi and now you're running 13 something at 20 psi. Sounds logical to me. If you're going to run 114 octane get a chip to take advantage of the octane and turn the boost up to 25 psi.

The stock turbo is done at 21psi, the 51 you have now will wake up after you turn the boost up.

So you think that even though it's more fuel and cooler air, it would net the same result?

If I get to go to the track this week I'll try cranking it up.

 

[BLACK6PACK]

There are many small things that could hinder performance, but based on what you've said, you've really done nothing that will make you go faster if you keep it at 20 psi of boost.

Actually 114 octane and 20 psi may slow you down. Higher octane gas burns slower. Set your car up with 16 psi and 93 octane, and again with 16 psi and 114 octane and you'll go slower with the 114. You actually want to run the lowest possible octane for your setup. 100 octane would probably work better with your current setup, but if you use 114, crank the boost up to 25 psi and use a race gas race chip. Take your time turning up the boost though. Bump it up a couple of pounds to start, and then up it, 1 psi per run until it starts to knock and then back it down a little.

Also, adding more fuel can also slow you down. Remember "lean is mean." Although too lean is "boom!"

 

[DCVING 6]

if memory serves me correct the orange stripe converter is only 2800 stall. You may need more than that with a PT-51.

How much boost are you launching with? What kind of 60 foot times are you getting?

 

[Scott231]

Jer-

You are jumping to conclusions by comparing apples to -well almost- oranges. I believe you went 13.05 at 99.86 at National Trail raceway in Columbus ( a nice flat track) prior to damaging the car. I believe this was with a quasi-race chip for pump gas and alchohol.

Now you have a different rolling chasssis. It includes a roll bar (which is prolly another 100 pounds over the last car). You were running a street chip at Salem. The tires you were using just came off of sitting in a garage for a year. Nor are we sure that the alignment is the same with this car. As such, this is not a case of apples to apples. Although you have larger injectors, their pulsewidth is turned way back such that you should be getting the same amount of fuel as before (that's assuming the 55# chip is providing the same amount).

Running a 13.12 at 101 with the same boost in a "new car" at a track that runs both downhill and uphill on only the third time the car has been down the track since being rebuilt, is prolly more of an improvement than you are willing to accept. As was mentioned, you should now be running more boost with the bigger turbo. And those old ET Streets aren't going to cut the mustard with your old stock suspension. We'll get you there.

 

[wickedtt]

what was your react and 60ft times?any knock?street tires or slicks,also psi boost leaving the line?

 

[T-top87GN]

Thanks for all of the input guys.

I guess maybe I am expecting a little too much a little too soon.

Scott, you want to head out to the trails this Friday? Kenny and myself are considering it. We pulled the ESC module off of my wrecked car and got his running right.

if memory serves me correct the orange stripe converter is only 2800 stall. You may need more than that with a PT-51.

Thanks for the input Glen, but I did do a little reseach before I purchased the turbo and a 2800 stall should be fine with this turbo. I don't have any problem boostin that bad boy up.
http://www.precisionte.com/buick.php

what was your react and 60ft times?any knock?street tires or slicks,also psi boost leaving the line?

React would be kind of pointless in this process . 60 fts were 1.8s and luanched at 10psi. BFG drag Radials and only false knock on the shifts.


Again guys thanks for all of the input. I just had my sights set really high and I think I expected too much.

This Friday will see the boost cranked and the FP as well.

I'll keep ya posted!

PS -- I need to fix my sig!!

 

[Eds87GN]

Bandit, the Orange Stripe converter as sold through the GS Club has a 3000 stall. Just thought you'd like to know.

Ed

 

[T-top87GN]

Originally posted by Eds87GN
Bandit, the Orange Stripe converter as sold through the GS Club has a 3000 stall. Just thought you'd like to know.

Ed

Ed, I purchased this Orange Stripe from Modern Muscle a while back.

Is the club unit made by Transcrafters? If it is then this is the same unit that Modern Muscle used to sell.

 

[Medbull]

Very well put Scott!

 

[murphster]

If Scott is right about your chips, then that would explain your times. If you were using a higher timing chip on the old combo and then used a lower timing chip on your new combo, then you did pretty good because the increased flow of the bigger turbo at the same boost probably made up for the lower timing giving the same results. Also, the difference in turbos, like stated above, will become more obvious as the boost is raised above 21-22lbs or so, when the stock turbo starts to crap out and the 51 will wake up.

Also, what BLACK6PACK said about the higher octane burning slower is not quite right, but its true that adding too much fuel will slow you down. Octane is not related to burning rate, so using by using the 114 you will do no harm, just might waste a little money if the chip doesn't need that octane. What you do need to be careful about when using the higher octane is that most of the time when people use higher octane they are also using a chip made for higher octane. A higher octane chip usually increases the timing and fuel curves and usually there is a recommended boost setting for the chip with a certain combo (chip makers don't put that in there for the heck of it ). If you don't increase the boost when changing to the higher octane chip the engine will not need all the extra fuel and the result will be that the car will be rich and may run slower. So a car with a street chip running 18lbs boost on 97 octane or whatever could run slower than with a race chip at 18lbs boost on 114 octane. The race chip will need more boost, say 24lbs for example, and at 18lbs will be too rich. Not due to the octane but due to the extra fuel added into the race chip without raising the boost accordingly.

Hope this makes sense. Get all these things figured out and what octane/boost/timing to run and you will be going fast in no time.

 

[BLACK6PACK]

Actually octane is "somewhat" related to burn rate. While its not exact, the components that raise the octane of gas tend to also slow down the burn rate. There may not be a 100% coralation, but you can pretty much bet that if it has a high octane rating it will burn slower than a lower octane fuel.

 

[murphster]

Originally posted by BLACK6PACK
Actually octane is "somewhat" related to burn rate. While its not exact, the components that raise the octane of gas tend to also slow down the burn rate. There may not be a 100% coralation, but you can pretty much bet that if it has a high octane rating it will burn slower than a lower octane fuel.

Not true. While this can be true for some brands of gasoline, some higher octane gasoline brands can burn at a higher rate than lower octanes. There is no way of knowing this unless you know what brand each is. On the other hand, it is much more likely that someone is running rich due to having a race chip and race gas but not having enough boost recommended for the chip.

here's a nice quote from this thread (originally posted by Ormand):
http://www.turbobuick.com/forums/showthread.php?s=&threadid=111156

There are a lot of people who mistakenly think that high octane fuel burns more slowly, and that has been spread around on the internet, even though it is not correct. Here is a quote, originally from Popular Hot Rodding:

"The burn rate of a fuel is a measurement of the time required
for complete combustion of the air/fuel mixture. The notion that octane ratings affect the burn rate of fuel is about 180-degrees from reality;
bum rate is a function of several variables, and the two are completely independent, although there is generally a correlation between octane ratings and bum rates.

To give you a good example of this, we contacted Jim Wurth from
Sunoco Race Fuels. He explains, "A perfect example is Sunoco Maximal,which is our fastest burning fuel, and coincidentally one of Sunoco'shighest octane fuels at 116 (R+M) / 2. A lot of Pro Stock teams rely on Maximal for those sub-seven second runs. When they are turning 9,000 rpm or more, the fuel has to burn pretty quickly to achieve complete combustion."

 

[T-top87GN]

Very interesting info guys thanks.

I'm gonna run a race chip this friday and crank the boost and fuel till it knocks!

Hopefully I won't be doing HG's on Saturday.

 

[GNVYUS 1]

PT 51 at 20 psi
3" DP
3000 stall stock remanned converter
1.8 60ft lauching at 10psi on drag radials
55lbs and wot 02's around 770
E.T.= 13.0??

What is the blm at during your runs?
What rpm is the car shifting at?
Are you running a test pipe, bigger exhaust?

The tires are pulling a decent 60ft for that ET, so even if they were flat, they did a decent job.

Sounds like you need to leave even harder, and your blm might be in the 115 range and doggin it out of the hole.

Are you spinning out of the hole? If not, then crank it up some more.

And IF your trans is bad, it could be shifting early on you and slowin you down aside from efficiency losses.

20 psi on race gas is weak, go 25 psi on 22 degrees and see what happens.

Hope you find the 12's soon.

 

[Eds87GN]

Bandit, yes the club unit was made by Transcrafters.

And I have DirectScan also but haven't used it enough to know a lot about it. But...is there a way to know if your transmission is slipping using it?

Ed

 

[T-top87GN]

Mike;

What is the blm at during your runs?

128 except for the very first half sec of the run when it is 130

What rpm is the car shifting at?

According to DirectScan, 1st-2nd is 5225 and 2nd-3rd is 5100

Are you running a test pipe, bigger exhaust?

Yes, a 3in DP, 3in test pipe and 2 1/2" duals.

In your statement you say to go ahead and turn up the boost. Even with 770 O2's I should turn up the boost? Or should I be turning up the fuel as well?

Thanks for the analysis Mike. I'm taking everyone's advice into consideration. I seem to like to over analyze things.

Ed;

Ok I thought that Transcrafters made the orange stripe that the club sells. That would mean I do have the same one.

I was basing my transmission slipping comment on the fact that my car was using all of the fuel that was being thrown at it and my 3rd gear rpm climb was sorta flat. My theory was that 3rd was slipping and the motor was putting down the power, but it was not etting through to the wheels.

As a side note to everyone, I can e-mail out DirectScan log files if anyone wishes to see them.

 

[BLACK6PACK]

Hmmmm....

It said in that quote "although there is generally a correlation between octane ratings and bum rates." I think that is almost exactly what I said. So, they quoted one fuel that has a quick burn rate and high octane. I've done some research on this. MOST high octane fuel burns slower!

Here's a chemists take on it...

Higher octane has a higher threshold of energy level required to start combustion, therefore there is less chance of detonation. If a engine is not detonating, higher octane WILL MAKE LESS POWER. Use the lowest octane without detonation. Remember that the knock sensor on our cars are pretty sensitive and the EEC will RETARD the timing when knock is detected.

There are two types of detonation, part throttle and full throttle. For part throttle detonation, a higher research octane is needed. For full throttle detonation, higher motor octane is needed. These numbers are not published on the gas pump, and each oil company has slightly different numbers. These mixes also change during the season, different temperature weather requires different mix gasoline. Changing brands of gasoline during the year can minimize detonation in engines that operate "near the edge".

The rate of the reaction is controlled by the distribution, molecular proximity, andrelative amounts of the reactants, i.e. how even and how rich the mixture.If the fuel and oxygen are well mixed (why airflow and turbulence in the head and cylinder are important) it will burn quickly and evenly.Detonation is not a problem with burn rate, but with spontaneous combustion initiating somewhere other than at the spark plug gap. Raising the threshold energy for reaction insures that it only initiates from the firing of the spark plug. Higher octane fuel does NOT mean higher power (essentially the same amountof energy inall gasoline). However, higher percentage of octane molecules does. However octane rating is obtained by various means, and seldom by the more expensive method of increasing the percentage of actual octane molecules. Octane rating is simply a measure of detonation resistance, which can be achieved by adding chemicals (like lead) that inhibit combustion. Actual high levels of octane molecules raised the threshold energy by raising the top of the energy release curve, making the drop, and hence the energy release, greater.