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Discussion Starter · #1 ·
Just a mock-up currently, but getting closer to bolting it all together. Hmmm, looks fast sitting still....
 

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very cool that reminds me i was digging around a few days ago (looking for 2.2 parts) and found an article called

Opel 2.3 Liter Hillclimb Engine Specifications
by Rally Bob

ha ha cant even remember how old it is

Davegt27
 

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Discussion Starter · #4 ·
ConreroGT said:
Those are some killer lookin headers Bob. Too bad they wouldn't fit on a GT...looks like it'd be too tight near the bottom.
Thanks. They won't fit a Manta either, not without cutting the floor! I made that header over a Saturday's worth of thrashing a bunch of years ago, for my hillclimb car that never got to see Mt. Washington. That car had the entire passenger floor cut out and reskinned for a concealed exhaust and extensive rollcage work. I can make this header work on the Turd, but it will have to have the floor modified to fit somewhat.

Bob
 

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"Heavy Breathing"

WOW! I do some heavy breathing just looking at those pictures!

Cutting the floor seems a small price to pay to be able to use them.
 

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Discussion Starter · #6 ·
Just a heads up folks, these cars aren't getting any younger. If your Opel was ever operated in any of the rust belt states, make sure your fuel and brake lines are replaced! In fact, any rubber lines are long overdue for replacement, but even the metal lines should use some scrutinizing.

Of the last two Opels I worked, one had a failed metal brake line on the rear diff. housing, the other (the Turd) had a failed rubber fuel hose and a cracked (rusted) metal fuel return line. Of course, the Turd will be getting all new brake and fuel lines. Safety first!

Bob
 

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Discussion Starter · #7 ·
Okay, after a few days of mulling over installing the header from the hillclimb car onto the Turd, I realized a lot more of the floor would be cut away than originally anticipated. I remembered that the hillclimb exhaust system was designed to be mounted completely above the floor level, and with a co-driver needed for a rally car, this won't do. I'm not against modifying the floor to fit a header, but competely removing it and fabricating one from the ground up is a bit more work.

I got a bit pumped up and decided to build a new (simple) header. It's not exactly equal length (varies from 32"-36"), but far easier to fabricate and a better fit with the dual sidedrafts as well. So I attacked the project with uncommon (for me) aggression, and had it completely fitted and tack welded in a bit under 4 hours! Then I realized I didn't have a collector in this tubing size (1 5/8" to 2 1/4"), and decided to try my hand at making one from scratch. It took another 2 hours to build, but it was kinda satisfying just the same. I figure another 1-1.5 hours to weld everything 100%.
 

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Bob, you did it again. Absolutly fantastic!! One minor query, is it possible to run unequal length header pipes into the collector to make them equal length from port to inside the collector? Just curious if the flow characteristics are that critical. Just how long did it take you to figure out the lengths and bends to get the length of pipes that close? Really looks good. Take a bow. :D
 

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Looks great Bob.

I'm surprised to see you built it out of the car like that. Have you done this enough that you know exactly where the floor is, or are you just not too worried as you're willing to cut the floor as needed?

Also, I've heard good things about reshaping the end of the tubes where they enter the collector to help minimize exhaust gas expansion as shown in this pic. Any thoughts on this?

-Travis
 

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Discussion Starter · #11 ·
namba209 said:
Bob, you did it again. Absolutly fantastic!! One minor query, is it possible to run unequal length header pipes into the collector to make them equal length from port to inside the collector? Just curious if the flow characteristics are that critical. Just how long did it take you to figure out the lengths and bends to get the length of pipes that close? Really looks good. Take a bow. :D
Thanks Ron, I'm very happy with the results relative to the time spent on this header. The collector is arguably the most important part of the header, so the fit and finish of the transition between the header tubes and collector is most crucial.

I got started on the header at 11:10 this morning, and at 3:06 pm I was done tacking the last tube in place. I basically designed it as I went along. Number one tube ended up at 36", number two and number four ended up at 34", and number three ended up at 32". I could have extended the #3 tube from the header flange a couple of inches to make that one 34" as well, but I only thought about it after I was 3/4 done with the whole header. I'm not too worried about the 4" discrepancy, it's world's better than a Pacesetter (about 9" variance from shortest to longest with the shortest being just 19" long). Basically just having the header tubes longer than 30" makes a world of difference in terms of torque production, short tubes are tuned for higher rpms.

Bob
 

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Discussion Starter · #12 ·
Travis said:
Looks great Bob.

I'm surprised to see you built it out of the car like that. Have you done this enough that you know exactly where the floor is, or are you just not too worried as you're willing to cut the floor as needed?

Also, I've heard good things about reshaping the end of the tubes where they enter the collector to help minimize exhaust gas expansion as shown in this pic. Any thoughts on this?

-Travis
I was concerned with the height relative to the sway bar, and that the width was narrower than the old header, which it is on both counts. I will still have to modify the floor, but not nearly as much.

I will be modifying the outlet of the tubes very similarly to that of a Burn's collector. Which is to say a bit more labor intensive that the 'X' shown in your pic. But I've done the 'X' technique for years on all my other headers based on input I got from 'Headers by Ed'. The hillclimb header is done this exact same way. It will be my first attempt at a Burn's type collector.

Bob
 

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Very nice. That one is much simpler than the hillclimb header. Questions...
Are you bending the tubes or using "U-build" header parts?
As the tubes enter the collector, aren't they supposed to follow the firing order around the circle?
Do you use "header wrap" to keep heat off the intakes?
Can you post a picture of the other side of the engine so I can see how you've got the block bolted up to the stand?
Lastly, how come the head is painted the same color as my engine?
Thanks, and keep up the good work!
 

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Discussion Starter · #15 ·
jeff denton said:
Very nice. That one is much simpler than the hillclimb header. Questions...
Are you bending the tubes or using "U-build" header parts?
As the tubes enter the collector, aren't they supposed to follow the firing order around the circle?
Do you use "header wrap" to keep heat off the intakes?
Can you post a picture of the other side of the engine so I can see how you've got the block bolted up to the stand?
Lastly, how come the head is painted the same color as my engine?
Thanks, and keep up the good work!
I'm using pre-bent 'U's' and 'J's', something about that $125K pricetag for a proper mandrel-bender didn't sit well with me.... :rolleyes:

I've built headers following no particular firing order sequence, as well as clockwise and counterclockwise rotation. I can't honestly say it has shown any difference.

Hmmm, the old header wrap dilemna. It definitely works. It also eats the header tubes up pretty fast. A non-coated header tube (mild steel) might last 2-3 years with header wrap before essentially decomposing from high heat. I prefer header coatings, which I will use once the header is final-fitted to the chassis.

This thread shows a pic of the engine stand right after I built it. http://www.opelgt.com/forums/showpost.php?p=31845&postcount=269

HTH!
Bob
 

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Discussion Starter · #17 ·
jeff denton said:
But what about the Terex green paint on the head? Is that a "Bob Special Head" by any chance? Painted to match my engine for any particular reason? :)
It's a 1.7 head I got from an Opel racer from Florida. His color choice, not mine! He gave it to me fairly recently, it's going onto my 2.4 stroker shortblock for my wagon and it will have about 10.8:1 compression with dished pistons!

It's not a 'special' head yet, but it will be soon. It's already got small chambers to begin with, but it's milled about .050" too. It'll have 1.85" intake valves and 1.50" exhaust valves, my 'leftover' .498" lift/245 degree roller camshaft, roller rockers, and a stud girdle. And of course full-tilt porting....
But it'll get painted another color, don't want to infringe any patents :p

Bob
 

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RallyBob said:
It's not exactly equal length (varies from 32"-36"), but far easier to fabricate and a better fit with the dual sidedrafts as well.
While mulling over parts selection for my 2.2, someone gave me a piece of advice. Gregg said "put it together and go have fun". I am not sure if that applies to this particular project, that's just what he said. :cool:
 

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Discussion Starter · #20 ·
madhatterpdc said:
While mulling over parts selection for my 2.2, someone gave me a piece of advice. Gregg said "put it together and go have fun". I am not sure if that applies to this particular project, that's just what he said. :cool:
Hmmm, everything about this car is custom-fabricated though, so 'putting it together' is not that easy! One thing's for sure, this car will not be the sum of it's parts, I think everything on it is worth more than the car as a whole!

As usual though, I got carried away with the whole project. One thing leads to another, and pretty soon every part of the car needs to be rebuilt. It had rusted brakes (two frozen calipers when you got a ride in it), a broken fuel line, bad fuel pump (high speed misfire), no heater/defroster, bad battery, etc.
So other than the body shell, it has turned into a complete overhaul of all mechanical systems.

But as far as having some fun, heck, that's the whole idea with the Turd. :D
 
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