88 #57 Recipe for power

[boostedmaxPSI]

Here is my first dyno run with this car. Car is completely stock however, completely untuned and neglected by previous owner.

My purpose of these posts is to help current and future CTTC owners who are looking at what are the next steps for their car. I have over 60 dyno pulls on my car to better understand what this car is capable of.

It's my guess that most stock CTTC from '88 - '91 are putting down low 300hp and low to mid 400tq to the wheels. But with a little know how more is available.

It's my belief that if your car still has the MicroFueler, "MF'r" you are not only stressing your engine but leaving power on the table. I came to this conclusion after testing 3 MF'r from 3 different years with the same results. I can also claim that I have close to 45 dyno pulls trying to correct the MF'r before I decided to go to another AIC, Aux Injector Controller, unit.

As you can see with this dyno chart, my AF is all over the place and it's not only hurting power but notice how the HP and TQ is up and down, that's stress on the motor as it's trying to accomodate what the MF'r doing.

 

[boostedmaxPSI]

New AIC installed

After countless hours of messing with the MF'r I gave up and installed a new AIC controller. As stated in my first post, I have a lot of dyno pulls testing three separate MF'r with the same results. I had Callaway Cars rebuild my MF'r and still no change. A/F was all over the place and still stressing my motor.

This dyno sheet is the result of my very first pass with a new AIC unit using the same wiring harness and boost line that my MF'r was using.

Not a bad gain by simply changing the MF'r. Notice how smooth the power band and A/F ratio is now. Car drives much better and power is so much more smooth on the street.

 

[boostedmaxPSI]

Correcting AF with new AIC unit

After just two pulls I was able to correct the AF ratio and feel good about the safety of the engine.

 

[boostedmaxPSI]

Final run

Run 65 was my final run after playing with more boost and timing. With runs 47 thru 65 I was able to turn up the boost and play with base timing.

My combo for all runs start to finish are with stock tune with cats and mufflers. The very first run was with the car completely stock...

December 2007 I put in the BIG Wonderbar and only found modest gains however, also found that with only 20K miles on my CTTC my distributor gear was completely worn out and I was loosing timing. There have been other CTTC owners who have also had this same issue.

I replaced the dissy gear and went back to the dyno and put down a nice 383HP and 503Tq to the wheels with what I found out later to be only 4* of timing and 12psi. I was happy with that and locked everything down

With my quest for more power, I kept wondering what this car would do if I turned up the boost to 15psi. What I found was there was absolutely no gain in power. EVERY SINGLE DYNO run is made at the same shop on the same dyno. What concluded is that I have an airflow choke point. MAF, TPI, rocker ratio, exhaust. Several points are limiting me to take advantage of more boost.

While strapped down to the dyno I wanted to verify my timing. It was then that I discovered that I was only using 4* of base timing. So, I changed the timing to 6* and TQ/HP had a nice increase. I adjusted the base timing again to 8* of base timing and again TQ/HP numbers increased. I thought why not check 10* for fun and found no gains so I set it back to 8* which is represented in this dyno chart. Notice the final A/F ratio at max power is 11.78:1.

In my tuning I was able to get 409hp however, the balance with TQ was not optimum.

My current setup is an open air filter using K&N, Big Wonderbar, Stock Tune and Stock TPI running thru high flow cats, true 2.5" dual exhaust and Magnaflow mufflers designed for a turbo application.

 

[boostedmaxPSI]

Timing change

This dyno pull shows the gain from just a modest change in the base timing.

I still have a couple more things to do one being a custom tune to clean up the fuel at both low and high RPM range and clean up the timing in the chip. The best part is this car is completely emission compliant and passes the sniffer and visual test with no problems and so much more a joy to drive and own then when I first brought her home.

This car is a true testament to GM and Callaway Cars and the power that can still be made. This is a 20 year old car that can hang with the best of exotics today. Thanks GM and Callaway Cars for building such an amazing car.

 

[boostedmaxPSI]

Final result

Here are my uncorrected numbers. Using SAE numbers helps even the playing Fields for those cars that are in high altitude locations or where there's high humidity climates. For those climates using SAE numbers should help them and uncorrected numbers should hurt them. Here in Texas using SAE numbers actually hurt my numbers and uncorrected using true Texas climate proved to be the best. This is what my butt actually feels SurfnSun may disagree :L

Nonetheless, my goal was to have a safe and powerful tune for Texas not just getting numbers.

enjoy.

 

[boostedmaxPSI]

SuperNatural tuning

...and I've started on my Callaway 435 SuperNatural. We'll have to wait to see what this car can do : )

http://www.youtube.com/watch?v=Xiv2IL3oBzw

 

[SurfnSun]

Now THIS is a great thread!!!!

Here in Texas using SAE numbers actually hurt my numbers and uncorrected using true Texas climate proved to be the best. This is what my butt actually feels SurfnSun may disagree :L

Hey man Im all for your uncorrected numbers the guys in Denver might want to see your SAE's :L I wish I had the sheet of my uncorrected numbers Somewhere around 455rwhp/600+rwtq

 

[calawyclif]

I agree ..this is a great thread...I am in CT so once the weather breaks I am going straight to a dyno....hahaha....very curious about the supernatural results..keep em coming, always wondered if there is much of a difference between cars for Hp & TQ...nice looking cars...Thanx for all the great info

 

[*89x2*]

Now THIS is a great thread!!!!

I agree as well - Thanks Frank, for taking the time to doccument your trials on the car

 

[8388]

Frank needs to pull the cats

 

[shopview]

Great thread! Love that Hardtop on the SNAT!

 

[*89x2*]

Great thread! Love that Hardtop on the SNAT!

...looks like he borrowed some of Sam's wheels, too :ugh

.
.

 

[8388]

...looks like he borrowed some of Sam's wheels, too :ugh

.
.

I noticed that

 

[CALLAWAY1988]

Frank, you mentioned an issue with the distributor breaking up. Your vehicle has 20,000 miles, and mine has 22 or 23,000. Sometimes when I kick it, I have experienced what feels like a backfire, loss of power issue. My dyno runs did not show that wavy power line, but, when i did the dyno, I did not experience the same load conditions. You said, worn out. Give me a clue what to look for.

 

[8388]

Frank, you mentioned an issue with the distributor breaking up. Your vehicle has 20,000 miles, and mine has 22 or 23,000. Sometimes when I kick it, I have experienced what feels like a backfire, loss of power issue. My dyno runs did not show that wavy power line, but, when i did the dyno, I did not experience the same load conditions. You said, worn out. Give me a clue what to look for.

You will need to pull the dist. and inspect the gear for wear. While you are at it, you will want to examine everything under the dist. cap as well. The newer engines most late 86 and newer, used a billet steel camshaft. These have the tendency to prematurely wear out the dist. gear. Only way to know for sure is to pull it and inspect.

P.S we have to use a thicker oil, as in 15w50 this in itself causes more torque pressure on the gear, as it has turn the oil pump.

 

[*89x2*]

Frank, you mentioned an issue with the distributor breaking up. Your vehicle has 20,000 miles, and mine has 22 or 23,000. Sometimes when I kick it, I have experienced what feels like a backfire, loss of power issue. My dyno runs did not show that wavy power line, but, when i did the dyno, I did not experience the same load conditions. You said, worn out. Give me a clue what to look for.

Your car may have a bit more *hot sauce* in its "recipe" than what is being discussed in this thread... hnoes

Did you ever find out the specs on it from the previous owner(s)

 

[boostedmaxPSI]

Frank, you mentioned an issue with the distributor breaking up. Your vehicle has 20,000 miles, and mine has 22 or 23,000. Sometimes when I kick it, I have experienced what feels like a backfire, loss of power issue. My dyno runs did not show that wavy power line, but, when i did the dyno, I did not experience the same load conditions. You said, worn out. Give me a clue what to look for.

I agree with 8388. Pulling the dissy to check is the best way to make sure and it's cheaper then having pop on you then get towed home There are a couple of reasons that this happens.

Here's a few pics... If you need more PM me with your email address and I can send more.

 

[*89x2*]

Frank, how about a rundown on how to adjust the boost through wastegate adjustments.


Details on how to fine tune each side for balance and what else you did to get the numbers.

Awesome thread

 

[CALLAWAY1988]

as you said, some extras are in this one. when we redone the engine, i looked at the shaft. no such wear. i installed new pieces in it, including button, cap, wires, and such. i want to get it back in for more dyno pulls. i just need to work with the shop and watch the adjustments as we test the car. if we can get more fuel to it, i am confident we can move the numbers higher.