Pace Car Race CarProject - The final chapter in our budget engine build #8

The final chapter in our budget engine build

Over the past 22 years, in RPM MAG we have approached our projects and installs differently. We never throw out the “build a small block for 500 bucks in your garage” bait, and we always try to make our projects and installs, at any level, be repeatable by readers. In other words, you should be able to do what we do and get similar results. Hopefully, though, by sharing our experiences with you, you can avoid some of the challenges we run into, because in RPM we give you the good, the bad, and the ugly of a project, and do it in real time!

That being said, it has been a pleasure to work with RPM readers on Project Pace Car Race Car’s budget engine build. We made it work through a pandemic, which is an accomplishment in itself. Thanks to all those who supported the project and be sure to check out our Source Box at the end of this article for some of the best companies in the business of go fast parts and service.

A few weeks back we were able to book a day at Misener Motorsports AKA the Dynocologist. It is finally time to get some dyno pulls in on the Pace Car Race Car. I remember years back, we needed to go to the track, often on race weekend, to test and along the way acquire data. When you’re on a budget it is hard to stick to the golden rule; don’t test on race day. Nowadays, we can go to Jay’s and

test and acquire data in a warm shop, even while it’s snowing outside. Oh how times have changed!

Anyway, last month we applied spark and fuel to the stock block SBF, TFS Twisted Wedge R headed bullet in our RPM PCRC project. She fired up flawlessly, attributing to our old motto - double and triple check each system to make sure our team wins.

Click here to watch us Adjust the Valve Train on the Pace Car Race Car

We needed fuel for the dyno session. I have personally used VP Racing Fuels for as many years as I can recall. It has been my standard for all my drag cars and it was my choice to stick with what we knew worked.

Story & Photos: Tim Biro

Here we are on a cold winters day at Misener Motorsports Dyno room. We are ready to get some solid data for the eventual first run down the track with our stock block Pace Car Race Car project! Once the engine and driveline have heat in them, we will do a light motor hit or two on the dyno first, as mostly we want nitrous system tune data…..note that we’ll just be adding a little nitrous this time, baby steps.

Since the early seventies, Steve Burns, the founder of VP Fuels, has kept his passion for drag racing as the driving force to create fuels for all levels of performance machines.

We used VP Fuels C-10 for the PCRC startup and took some to the dyno session so we could double check everything by heating up the engine and drivetrain a good couple times on it. The Misener dyno session

is mainly a chance for us to tune the fuel system and the nitrous hit to arrive at a safe base tune-up. As drag racers, we know nothing substitutes the data acquired at the track, and that testing will come in spring. For the nitrous oxide tune, we needed to use VP Fuels C-16. With the high compression and 200 - 300hp hit of nitrous oxide, the PCRC bullet will run best on the VP C-16 fuel. VP has a great website and excellent tech support system. If you need fuel for your machine of any performance level, VP can supply an off-the-shelf fuel or make a custom fuel for your requirements.

I have been using nitrous oxide as a successful power adder for many years. What we need to understand when using any power adder, (boost or nitrous), the engine package must follow certain rules. Rules like parts selection, clearances, compression, camshaft events, and tune-up. The power comes from the amount of fuel you can burn efficiently - fuel needs the air to burn and make the power. Today, we use the wideband oxygen sensor to monitor fuel/air ratios. No more seat of the pants driving down a track to tell your buddies, yeah, she feels a little fat! To compliment the data we gain from the widebands, another classic method to check tune-up is reading spark plugs. We visually see what kind of burn we have in the chamber, through spark plug reading. Try to learn this skill as you can detect oil migration, timing issues, excessive heat depending on the fuel you are using and so on. All

this said, try to resist the temptation to reach ultimate power numbers and go to the edge on your tune-up. Always have a plan for a bit more power, and these days, with many types of no prep racing, you need to know how to back the power off as well.

After checking all systems and a couple heat cycles on Misener’s Dyno, we were ready to make the first dyno pull. After the first pull, air/fuel trim looked lean at the top of the rpm cycle. After discussion, we decided to add more jet and a few more minor tweaks to our new carburetor. The ending jet on our 1050cfm 4150 style

carburetor is 89 squared. Our timing was a very safe 30 degrees total. With my experience, we could probably make a bit more power by playing with the timing, but I resisted the temptation, as we are here primarily to make some nitrous hits. After these fuel changes, we found that the engine sounded strong and the A/F ratio came right into line. Next step

A shameless plug for RPM swag; be sure to visit our Shopify store: rpm-mag.myshopify.com

After some motor runs, the valves are set, carb jetted, timing is programmed, all we need to do is set the fuel pressure for the nitrous hit.

Click here to watch us start the Pace Car Race Car for the first fire up!

(Right) Check out our Project Costing Sheet. We came in at a very respectable budget for this build (Left) Here we use a high quality large face gauge to check and set our flowing fuel pressure. Nitrous bottle pressure to 1000 psi and we are ready for the nitrous dyno pull.

was to check all systems of the nitrous kit.

As mentioned early on in the Pace Car Race Car series, with budget in mind, we assembled this nitrous oxide kit with many different used components we had on the shelf. That is not to say that we didn’t triple check every part, as knowing that solenoids are opening and staying open is very important. Just as important is the ratio of nitrous to fuel. Nitrous oxide is an oxygen rich liquid that gives your internal combustion engine the abil-

Used OEM 9.500 deck / 4.030 inch bore Windsor Block

Used Steel Crank 3.750 inch stroke XXXXX 200 200

Balance Service XXXXX 300 300 Trick Flow Specialties

Cylinder Heads TW R 5241T805-C01 1550 3100

Wiseco Piston and ring set WD-10185 1650 1650

Comp Cams Camshaft 35-782-9 406 406

Comp Cams Lifters Solid Roller 96838B-16 935 935

Comp Cams Valve Springs / Retainers 947-16/ 722-16 385+ 325 710

Comp Cams Cam Timing Kit 3135KT 220 220 Comp Cams Push Rods 7778-16 160 160 Comp Cams Locators /Shims / Locks /Seals 4708/4756/611-16/506-16 33+27+27+38 125

Harland Sharp Roller Rocker Arm Kit S4403 380 380 Harland Sharp Rocker Arm Stud Girdle G4404 250 250

Used oil pan, timing cover and water pump XXXXX 75+20+50 145 Eagle Rods CRS6250B3D2000 550 550 Damper XXXXX 120 120 Bearings- rod and main XXXXX 100 100 Gasket Kit XXXXX 300 300 Used flexplate XXXXX 75 75 Valve Covers XXXXX 100 100 Intake Manifold 2924 440 440 Headers XXXXX 600 600 Carburetor FSC4150B 850 850 Silicone and oils XXXXX 50 50 Hardware ARP and Misc. used 200 200 Total

ity to burn more fuel. Burn more fuel and you make more power! That power comes at a price in the form of high cylinder pressures and heat, though, so there are certain rules you need to follow when using nitrous.

If you use over a 100hp jet, you should start to use colder plugs. Fuel/air ratios, as well as timing, are some of the most important tuning issues. If your combination is hurt or broken in any way, you cannot make it better with more nitrous oxide, this type of thinking leads

to catastrophic failure. Most nitrous companies have safe tune-ups - this is a good place to start. If you have a chance to talk to one of the greats in this field, you will be rewarded with a wealth of information. Today, there are many companies, but buy a trusted name kit and parts designed for your application, or have one designed for it, and go have some fun.

Our kit is a plate system with 2 fuel jets and 2 nitrous oxide jets. The 4 jets limit the amount of fuel and nitrous mixing in the plate spray bars. Before our first nitrous hit on the dyno, I always flow our fuel pressure as it is relative to the quantity of fuel in the tune-up. If you plan on tuning your kit with precision, buy a quality fuel pressure gauge. I have a large face high quality NX gauge that has led us to many successful tune-ups. Make sure your charging system is not only adequate, but operating at

the same voltage when the nitrous kit is activated. My experience has shown that you will not flow as much fuel at 11 volts as you would at 14 volts. Your tune-up can get pretty fat with 3 extra volts, not to mention what would happen with less voltage. Our tune-up starts at 6.5 flowing psi of fuel pressure. With that done, we need to get our bottle pressure correct, as bottle pressure also relates to flow. The minimum I like to see with this tune-up is 950psi at the solenoid, 1000psi at the bottle is great. Invest in a purge valve to help get this pressure correct, right at the solenoid. In our case, it was a pretty cold day and I left our bottle warmer at the shop. Next best thing is to pop the bottle into the truck with the heater on full blast. About an hour later, we saw 1000 psi in the bottle. While the bottle was warming, we double checked the wide open throttle ni-

Setting up the micro switch for wide open nitrous activation is a must. Before you engage the nitrous, the engine should be rolling past 3000 rpm and only activated at wide open throttle. This helps if you lose traction and need to get off the gas during a run.

trous activation switch mounted on our carb. It was set up to activate at about 95% full sweep, all good. The last check was our golf tee to verify our distributor was phased to our retarded timing. A little turn of the distributor and we were ready. As for the retarded timing, the MSD Grid made this very easy to adjust with a stroke of a key. With the 200hp jets in our nitrous plate, I pulled a full 10 degrees from our total timing to keep the tune-up super safe. All systems are a go!

Scotty sparked the engine of the Pace Car and drove it through low gear, shifted into high gear and mashed the accelerator! WOW! I love that sound of a well-tuned engine making power at rpm. The first 2 nitrous pulls were a little too aggressive - we spun the tire when the nitrous oxide hit. After tightening all the chassis straps and activating

Check out the info screens for our Motor and Nitrous dyno runs at Misener’s. The motor pull was fairly light as we only tuned to get a max of 200hp on juice.

Click here to watch us Dyno the Pace Car Race Car with Nitrous

MissionAccomplished!

Ah, not so distant memories of warmer weather. All that’s left is testing how our new budget motor performs on track! Of course, we’ll need to go through the car and tweak the chassis so we can make the best use of our power. We’ll start with this base tune and work forward from there. We’re very confident that making 777whp on this conservative base that we will easily achieve our goal of 800whp.

the system at a little higher rpm, we went for another hit. Again, the engine roared to life, sounding like full traction this time, YES! We should get some good data. If you recall, our goal was 800hp on nitrous so we were very happy as we made 777.48hp and 615.33 ft/ lb of torque at the tire. All this with a very safe tune-up under 7000rpm. Doing a little math, if our weight is where it should be, the car should go low 9’s, maybe into the 8 second zone in the ¼-mile.

After a good day at the dyno, the only thing left was to check the plugs, check the valve lash, a couple chassis modifications and then to the track! Come on, spring!