Time to Catch up, or is it Ketch up?

Well, it's been way too long since my last update so this one is going to be a doozy. I'll try and go chronical the events in the proper order but you'll have to forgive me if it seems I'm jumping around a little.

The Dyno Run - February 14th (Yes, Valentine's Day, sorry hun :) )

My appointment at DL Motorsports for my dyno run was 6 PM. Off course I got there at 5:30..lol. Mike was OK with that and he proceeded to get things ready. I really didn't know how this would work at first since I was a dyno virgin. I went in the back to check out the area, and I had to hold myself back a little because it looked like a scene from the Fast and the Furious....Rice was all over the place in there, although I have to admit there was a damn nice EVO in there.

Once Mike had cleared the area he asked that I "bring 'er in". So I drove to the back of the building and drove 'er onto the roller. I have to say now that The Sickness was misbehaving for the entire ride to the shop in the form of throttle hesitation, and hard starting, almost like she knew she was headed for abuse.

After Mike strapped her down, he proceeded to give me the basic procedures. We both agreed that the for the first run, we should cap it to 4000 RPM. Now before I go any further, let me point out the fact that the exhaust on the car is practically an straight pipe. The muffler consist of a Dynomax SS which is stuffed with fiberglass, and after awhile, that fiberglass basically burns out and the car gets progressively louder, and she is loud when you get on the gas. I'm public enemy #1 in my neighbourhood now.

I ran the first run in 4th gear (1:1 ratio) from 2000 to 4000 RPM. Lets just say the dyno graph was a little messed up. It looked more like a EKG from a 20 year old triathlete...all over the place. Mike and I agreed to make another run and this time I brought it up to 5000 RPM, and the graph looked normal this time. We came to the conclusion that the engine might not have been at full temperature. I did 2 more runs up to 6000 RPM and I'm going to be quite honest here; I was both getting chills and shitting my pants all in that 10-15 seconds it takes to bring that thing to 6000 grand. Why you might ask? Back to my above statement about the exhaust; We're in an enclosed garage with a small block Chevy screaming it's combustion chambers out to 6000 RPM. During the first 6000 RPM run, I was sure I'd be picking up piston chunks off the floor. I can't imagine being in a dyno room in North Carolina where they test 10,000 RPM, open header NASCAR engines. I'd be running for the hills.

Well, the bottom line was better than I thought; at the wheels I got 310 HP @ 5500 RPM, and 342 TQ @ 4000 RPM. Using the typical conversion factor, that equates to about 365 HP & 400 TQ at the flywheel, and those are SAE corrected numbers. This means it's corrected for temperature, humidity, and air density to SAE standards. I did a 5th run without the air filter assembly as I alway figured this was an air bottleneck, and sure enough I gained 12 HP by removing it.

You'll notice on the upper right I have now setup a Photo Gallery and in there you will find a scan of the dyno run along with a pic of the beast sitting in the rollers waiting to be spun.

I was very satisfied with the overall experience and can't wait to return to do more runs when I change a few things.


The Recon Mission - February 18th, 2006

Ever since I bought the car, I knew I would have to do some recon on the engine to see exactly what was under certain things; the heads primarily. Yes I knew they were Trick Flow Twisted Wedge aluminum heads, but back when these heads where put out, they had a couple of different variations. According to the tech dude at Trick Flow, I need to pull one of the headers off the head to get the stamped serial number. That number was 8362. Here is what the TF tech dude told me about my heads;

• First generation TFTW heads; at least 10 years old.
• 180cc Intake Runner
• 64cc Combustion Chamber
• 2.02/1.60 Valves
• Angled Plugs
  
• 3/8" Rocker studs (more on this later)
• 1.25" Valve springs but pockets machined to 1.5" (this is a good thing)
• Intake Flow: 240 cfm @ 0.500"
• Exhaust Flow: 190 cfm @ 0.500"
  

Great info. Those flow numbers means these will make at least 450 HP, and the bigger machined spring pockets means they will accomodate my dual springs for my roller cam without any machining.

I then proceed to pull a valve cover off to check things out under there. I then took my digital calipers and started measuring things;

• Pushrods - 5/16" CHECK
• Crane 1.5 ratio aluminum roller rockers CHECK
  
• Springs - 1.25" CHECK
• Spring pocket - 1.5" CHECK
• Rocker Stud - 7/16" CHE....hey wait. It's suppose to be 3/8"? DOH!!! I guess I don't need those 3/8" stud 1.6 ratio roller rockers I just bought off Ebay. ARGH.

Anyhow, I cleaned up everything and re-installed the valve cover and header. Here's a pick from under the valve cover;


While I had the tools out and was under the hood I decided to install my new billet distributor, and proceeded to time it to 16 deg. inital, 34 deg total by 2500 RPM. As it was from when I bought the car, it had 30 deg fixed timing..all the time. That's how I ran it at my initial dyno baseline.


The Recon Mission - Part Deux - February 23rd, 2006

Next on the hit list was the Edelbrock Performer 1411 750cfm carburator. I knew Tom (previous owner..Hi Tom!, How's the Vette?) had said he fooled around with the jetting along with removing the secondary booster flaps. Being that he tuned the carb at 5000 ft elevation where the air is clean, crisp and non-existant, he had to tune down the carb to the lean side. Being that the car is now sitting at about 700 ft, there's quite a bit more air therefore would need more fuel. I pulled a couple of spark plugs to see what kind of info I could get from them...OUCH!!! I should have check this way before I was turning the beast to 6000 RPM. The plugs showed signs of running lean being extremely white colored. I suprised I never heard any detonation or blew up at this point.

With that info, I proceed to remove the airhorn assembly of the carb to check what jets/rods where installed and compare that to what was in the Edelbrock manual. First thing I noticed was that he had installed the smallest metering rod Edelbrock makes for this carb which is meant to richen the power mixture, but further down, the primary jets was set very lean. But to my surprise, the seconday jets were set to 4% richer than stock. I left those intact, but I went 4% richer for both the cruise and power mixture on the primary side. I did not adjust the pump since I was not experiencing any stumble when I got on the gas. I also re-installed the secondary flaps.

I closed everything up and started 'er up. After it warmed up a bit, I went for a spin. I don't live far for the QEW highway (major 4 lane highway here) and there's a nice on-ramp that I love to "test" the acceleration. I got on the bottom to the ramp in 2nd gear at about 2500 RPM and slammed the gas down. Let's just say that I had a moment....when the car spun both rear tires and I started going sideway. After I managed to inhale and blink again, I got back on it and within a few seconds I was up to 90 MPH in 3rd gear. Now that I have reworked the carb and timing, and also installed a 180 deg thermostat, I plan on heading for the dyno again next week, March 9th. I'm pretty sure I gained at least 15-20 HP. We'll know in a week.


Do I shift now? How about now? Now? - February 25th, 2006

Optimizing your shift points when racing is key but hard to do if you have to look at the tach all the time. Next thing you know your sitting in a patch of tulips with a pissed off ol' lady yelling at you. Hence the "shift light". These little beauts can be set to flash you at specific RPM.

The installation was pretty straightforward and took a little over an hour to install. But I got another present with this installation in the form of a Air/Fuel ratio meter that was nicely tucked under the dash behind a removable front plate.

After I noticed this little gem, I started screaming like a little girl in joyfulness (small things amuse small minds don't they) then I realized that it might just be an ornament at this point. But then I started following the wires. This led me to the left side header where there was a 3-wire O2 sensor installed there. Then I thought; OK, but does it work? So I fire up the car and sure enough, "We've got contact!".

Anyhow, I proceed to finish my shift light install, after which time I went for some test runs to try out the light. I set it up for 5700 RPM since my last known HP peak was at 5500 RPM. The thing worked like a charm.

While on my ride, I decided to take a peak at the A/F meter at different stages of acceleration, cruise and WOT. This showed me that I am running too rich in cruise and part-throttle acceleration were the ratio runs in the 12.0 to 12.5. For cruising, 14 to 15 would be optimal, and 14.0-14.5 would be ideal for part-throttle power. The WOT reading was around 13 which is perfect so that means my seconday jetting is good. Tomorrow I will be changing the primary metering rods to see if I can increase those cruise & PT values.

Well, that's it for now. I'll be updating again shortly once I'm done changing over the rods, and again once I have new dyno results. Till next time; "If it ain't broke, tweak it!".