The Undercover

Well, it has been a long hard road, but here it is......... the Undercover chassis, rear engine, swing arm dragster. It has not been without its challenges, some of you understand what it takes to get something like this off center with limited resources. I have to say that going into this, I had no idea what I was doing, how it would turn out, or what i was getting myself into. This car has a old IR mechanical injection system that I converted to EFI, (see the previous post) which required some out of the box thinking, and many custom designed and machined/fabricated parts to implement the system into this application.

(Click on photos to enlarge, see previous thread for engine details)

(Stainless headers)



(Weld Alumastars, 2 piece)



(Designed the coil mount in CAD, cut on laser)

(4 Link with single shock)

(8.90 on the dial in, S/C standard)

(Delay box on left, AFR gauge on right)

SBC IR/EFI project

After selling the Racetech, i knew i would buy another dragster, and wanted to move from the slip joint car to a full suspension car. I also wanted to have something 'different' for a power plant rather than the carb or mechanical injected engine that every dragster has. After a little bit of research and looking at the options, Flathead Shaun found an old Individual Runner (IR) mechanical injected intake manifold. I knew I would also be moving to an electronic fuel injection (EFI) system, not very common in bracket dragsters, so i would be retrofitting the manifold to work with the EFI.

I designed the injection system in Solidworks. It allowed me to be able to have drawings for all of the parts that needed machined and lazer cut. It took me a great deal of time to get everything just right, it is more difficult than if looks. Things can get pretty tight when trying to implement all the EFI components, as well as a scoop. I always try to make each component have more than one purpose as seen in the block in the center of the manifold that contains the TPS and a small manifold block to draw a vacuum signal (the IR intake basically turns the engine into 8 individual cylinders)










(This is the manifold I started with, an old mechanical injection, I do not even know who made this unit for sure.)

In the conversion, I also needed an EFI controller. These can be a very expensive part of the conversion and a reason that people do not make the switch , so i put one together myself with a processor and board from group of enthusiasts that developed what is called a Megasquirt II . The great part about this is it is very versatile, and inexpensive as you build and configure it yourself as long as you are willing to put the time in and learn a few things. It was basically developed by a bunch of car guys that had a lot of programming, and IC engine knowledge and had some time on there hands. As such, all the software (tuning and data logging) is very inexpensive. The extra box on top is for the Low impedance injector drivers. I am running 120lb/hr low Z injectors on methanol (4A peak.1A hold) on a belt drive pump.


(processor etc on left, Low Z boards on right)



(I had to create a schematic for future troubleshooting)

(Data logging during tuning)

I purchased a long block from a guy in Michigan. It has a Dart Little M block, Brodix Track1 heads, Scat Crank, Oliver Rods, Wiesco pistons, 14.5:1 compression, Jesel shaft rockers/timing belt system, and a roller cam. Mounted to the front of the engine is a Moroso vacuum pump, CSR water pump, Aeromotive belt drive fuel pump, MSD crank trigger, and a Shogun alternator. I am running it on alcohol (methanol), and given the setup with the injection i am hoping that it will produce some good torque for a good ET. This engine produced 700 HP on the dyno with an alcohol carb.

(On the stand with the carb intake still on)

(Jesel shaft rockers)

(The throttle plates must be set after manifold is torqued, before the stacks go on)

(Fuel rails and headers installed)

(Way to many things mounted to the front of this engine!)

(Fuel shut off mounted off t-stat housing)

(FP regulator and return)

(ECU mounted)

(stacks installed)

(Note the TPS/MAP manifold in the center)

(scoop tray)

(AIT sensor in mounted in the center)

(Regulator through scoop tray)

Syncrowave 200

Earlier this year I decided that it was time to break down and buy a welder. I was getting into way to many situations that required a welder, and I knew that if I wanted to weld CM and Aluminum it had to be a TIG welder. I am getting pretty good at welding MS & CM and notching tubes. I have used a lot of small diameter CM in making the brackets etc. for the SBC project and it has come in real handy, my skills have improved a great deal this year. I found this unit on craigslist located between Cincinnati and Dayton, it came with the cart, helmet and I the guy threw this check fixture plate in with the deal that is a qualified check fixture from some discontinued automotive part. It works great for clamping work to since it is perfectly flat and has many threaded holes in it. When I bought the welder, there was 2 minuets on the usage timer, and i bought it for just over half of the new price when it was about 1.5 years old. I thought it was a screamin' deal.