'73 Vega GT All Aluminum Wildcat 355 Project

Contents:
Page 1: Engine Block prep
Page 2: Head mods
Page 3: Induction/Exhaust
Page 4: Engine Assembly
Page 5: Front Suspension Mods
Page 6: Rear Suspension/Weight Transfer Mods
Page 7: Rust Repair and Undercarriage prep
Page 8: Frame Rail fabrication/Unibody support
Page 9: Body Mods
Page 10: Transmission Mods
Page 11: T5 Rebuild
Page 12: BMW Radiator Swap

Induction:

I had to make a new page for the induction for my engine. I had planned on building an EFI system (MegaSquirt) using a modified Rover intake but I changed my mind for a couple reasons: I was having trouble figuring out how to control injection of alcohol blends like E40-E60, I really needed to simplify my project so I could get it on the road. I a little tired of building and building and not getting to try it out SO I decided to build an old school induction system with a well tuned carb.

After some research I landed on the Q-jet. I may change my mind on this if I can't maintain enough vacuum but I found this carb to be very tunable and a really great design. I like the CFM variability of the design especially. I downloaded a few tech papers on tuning them and was really hooked. I think this is the best designed carb ever. OK here's the caveat: It is really vacuum dependent. My cam specs are:

Crower 50232 with an intake lift of 0.488", an exhaust lift of 0.490", Duration 276º, Duration at 0.05": intake 214 degrees, exhaust 218 degrees. Lobe separation angle: 112 degrees.

I may be ok as this is more warm than HOT. So that may kibosh my whole plan and I'll have to use the Holley design. I really don't like that it but it's simple enough to have more vacuum tolerance.

I found a Q-jet from a '68 327 Malibu and went for it. I got it for $75! They usually go for around $120ish or more. I'm not really sure why this one didn't go for more. It's clean and just needs some work. It's a 750cfm. The smallest I could get. I'll be recording my tuning process below.

After I received the Q-jet I immediately slapped it on my Edelbrock performer 3.5 intake. It was pretty clear that this wasn't going to work with out some frankly major modification. I thought I'd look around to see if I could find a spread-bore intake I could use. As I was searching different intake manufacturers for the ROver I found this one: in an online ad by Triumph Rover Spears in South Australia.

I was pretty keyed up because I had never seen a spread-bore intake for my engine before. I quickly figured it was somehow modified from the original Harcourt intake. It came and here you can see it was modified by drilling and tapping the standard flange for the Q-jet flange.

The flange was then recessed to make room for the barrels. Here's a pic of the Q-jet sitting atop the intake.

As you can see it sits right on top with no problems. There is still some clearancing to do to clear the massive Q-jet secondaries but there is still about 1/4" to either side of the widest part of the secondaries to make it happen. I will likely get my machine shop to deck the flange for straightness.

Here you can see it sits pretty high. I'm not sure what clearance issues I might come up with in my car... There was also a simple coolent plenum heater fabbed into it. The braided lines are just for show. I'm not sure if it will work or just leak yet. I'll keep you posted.

Really the last feature of note is the water housing. It is different from the standard Harcourt in that they came with no coolent housing like this. They usually just have to ports cast into the intake port flange. This must have been welded on from a different unit...

Header Fabrication:

I started fabricating the Exhaust. I bought a couple collectors and a box of bending mistakes from Stahl Headers in PA. Absolutely GREAT company to work with. I messed up the original order saying 1 3/8" when I meant 1 5/8" and when the parts came and they were the wrong size they took them back and paid for part of the shipping. It was really a great experience. I hope to frequent their business and recommend them as much as I can. The headers are 1 5/8" primaries and 2 1/2" collectors. Here's a pic of the parts:

I started out using "Muscle Car" TV's idea of welding the collectors in place where they should end up. I wanted the primaries to be about 37" long. The collectors ended up right along side the trans in a convenient slot that appears on either side of the trans crossmember mount. The strange thing is it's symmetrical on both sides. It's almost like they planned on the Vega having dual exhaust! To the left is a pic of how far down the collectors hang. They are as snug as I could get them comfortably at 1/2" from the floors. Here also is a couple pix of the collector location:

I was able to get two tubes in last night. There is a lot of time just standing looking at the puzzle and planning the best solution. I have to thread the steering shaft through the headers too. You can see that in these pix. Having the rack steering although causing me to have to put the shaft between cyl 6 and 8 actually gave me more room to make the tube's transitions smoother than if I'd had the stock gear box/steering shaft location.

I finished the driver side last weekend. Here's some pix. I'm pretty keyed up about it. I was able to keep the lengths pretty close to about an inch from eachother. I feel confident saying it's less than an inch difference. That wasn't easy.

Here's a couple pix of the headers in place. I was able to fabricate this side so I could remove it pretty easily. It's pretty tight though.

I've also taken a pic of the header termination. They are 37" at this point. I'm still planning on potentially altering the length. I'm thinking they could be a bit shorter now since my cam is a lot different than I originally planned.

I just finished the the right side. It turned out to be a lot more difficult. Unexpected. I had forgotten that the exhaust tubes would have to bypass the starter. So my initial thought was to run both rear tubes up and back to add extra length to them. Then I remembered that the heater box was right there so I had to change my plan. I decided to run the last tube up and over the third port then back down to meet up with the first and second tubes just above the starter. I neglected to take a pic before I removed it and put the last of the tubing in. Now I can't get the header back in. I'll have to place it in the engine bay and then connect the
header after.

Here's a side view and the left over tubes. There's actualy a lot left over. Plenty of tube to fabricate my own headers. It's not like they were super straight forward either. I had to make a number of difficult turns. It worked out great though. Thanks Stahl Headers!

You can see how the rear tube goes over the top of the third port better in that pic too. The last issue, however, is the total length of he tubes on this side. I wasn't able to get them all to match up as well as the others because of the space constraints. That tube that loops over the third port is almost 2" longer. Disappointing. I'm going to try to leave the other tubes a bit longer in the collector and see if I can make up 1/2" or something

I'll get a couple more pix lined up on the assembled engine when I finish the fabrication. OK I finally finished the fabrication of the headers. It took a while to weld them up and then clean up the welds. I was difficult but really a lot of fun. I think they turned out great:

I installed my Percy's Adjust-a-Jet plates. It really makes the massive Holley even longer. LOL! It looks frickin' huge. I'm looking forward to using these adjusters. I've never gotten the side mounted bowl idea. It just seems like a recipe for leaking. Eliminating the need to remove these to tune will really be nice. They come with bent pumper arms. Works pretty well but I needed to remove some of the end so it didn't interfere with the pumper housing.