Opel GT Forum banner
1 - 20 of 60 Posts

·
Member 1000 Post Club
Joined
·
1,520 Posts
Discussion Starter · #1 ·
Well folks, after nearly 10 years of hibernation, my 75 Manta came back to life last night. I bought this very car when I was 16 years old. That makes me the original owner!

For the past 3 years I've spent a lot of time and way too much money on a 98.5% full mechanical rebuild. Over the next couple of weeks I hope I don't find myself sorry for not doing a full 100%.

As I get time, I'll post some pictures and list some of the details if anyone is interested.

Just for grins I'll list a few of the details of the project.

Engine: 1.9+.030; Total Seal Gapless second rings; Roger Wilson Head with 1.72/1.5 Valves with velocity ports for FI; Cam Techniques (RallyBob spec) cam H292/H284 222/212 Degrees @ .050; 17# flywheel, Early style Forged rods; TGSI underdrive crank pulley; Balanced rotating assembly.....

Exhaust: Crappy unequal length header; 2 inch pipe with mandrel bends back to a DynoMax Turbo II muffler, 2-1/4 with mandrel bends Over-the-Axle; Dual resonator chrome tips.

Suspension: 275#/170# springs 1-1/2 to 2 inch drop, Custom Valved Bilstein shocks; RallyBob spec adjustible PanHard Bar, OGTS Poly bushings everywhere except for front and rear sway bar, used rubber for that. Added grease fittings to bushings. Rebuilt rack and used Red Line CV-2 synthetic grease.

Brakes: New stuff everywhere; SS braided lines at each of 3 locations; Larger bore 3/4" rear wheel cylinders.

Interior: Recaro seats with Blaupunt (sp?) speakers in the head rests. New headliner; All new window rubber and trunk rubber... Thanks Charles: Polk speakers front and rear; Bazooka tube sub in the trunk, stole it from my Daughter's car... haha..

Exterior: No paint or body work... except 4 new Cibie headlights and the BMW BBS RZ 14 inch wheels

There are tons more I've done to the car and lots of people to thank.

A special thanks to Bob Legere for answering my emails and there have been dozens. OGTS for continueing to take my VISA...... and to everyone on this Forum for keeping the burning desire to complete the project.
 

·
Registered
Joined
·
275 Posts
Geez Paul! Ten years and all that work... big congratulations! That is some serious 'stick-to-itiveness'.
Now. We want pics - we want pics - we want pics! :D
(This sort of thing makes me feel like shutting up about a little thing like a scored crank. :p )
 

·
Registered
Joined
·
2,894 Posts
ging said:
Geez Paul! Ten years and all that work... big congratulations! That is some serious 'stick-to-itiveness'.
Now. We want pics - we want pics - we want pics! :D
Congratulations indeed! Like ging said "we want pics" I have a 74 Ralllye that has been neglected too long. Give us Manta owners that inspiration that to get up and rolling again. Jarrell
 

·
Member 1000 Post Club
Joined
·
1,520 Posts
Discussion Starter · #4 ·
I just stopped driving it 10 years ago. It had been my 600 mile per week commuter car. Finally I got a new car, and parked the Manta. When the battery went dead, about 6 months later, I quit driving it on weekends. I started 3 years ago, on a more or less part time basis, rebuilding it. Keith W. knows how that works!

But let's not get too excited yet. The tranny just locked up and I haven't even taken it for a ride. The pan gasket was leaking a little so I thought I'd pull it and get it taken care of before I take it to the muffler shop Wednesday morning first thing. Well wouldn't you know. I stick the tranny back in and something came loose and locked it up. No I didn't have it rebuilt. I only took it apart far enough to put in shifter shaft seals and new gaskets.

I guess I'll tear it apart in the morning instead of going to the muffler shop.
 

·
Member 1000 Post Club
Joined
·
1,520 Posts
Discussion Starter · #6 · (Edited)
Some Engine Shots

Here's a couple of pictures of the head by Roger's Opel Engineering. Intakes are 1.72 and Exhaust are 1.5, springs are Isky #905 D.

The ports are supposed to be velocity ports since I'm using the stock FI.

Yes, RallyBob dimples, why not.

One picture shows the difference in from a stock intake valve and the 1.72s.

If you look closely at picture #3, you can see how much the combustion chamber was unshrouded.
 

Attachments

·
Member 1000 Post Club
Joined
·
1,520 Posts
Discussion Starter · #7 ·
Here's a shot with the engine mostly assembled. Notice it has the factory crank pulley.

The next shot shows the underdrive pulley. Sweet

Yea, I know its the crappy unequal length header... But when I installed it in 1978, I cut the down pipe to remove it. I still have the pieces, but getting that welded up would be more trouble than it would be worth. So I'm putting this back on until..... a custom one can be made.....
 

Attachments

·
Registered
Joined
·
2,894 Posts
Paul, Is that the original paint, and is is Jade Mist? Great looking car. Jarrell
 

·
Member 1000 Post Club
Joined
·
1,520 Posts
Discussion Starter · #10 ·
4-2-1

Keith

Yea I saw those too. I don't have a really complete understanding of 4-2-1 headers, as opposed to 4 into 1s. The principals are similar, but there are differences. Most of the wave propagation math centers around the 4 into 1s. Also, there is no expansion chamber (read: collector) on a 4-2-1.

In other words. I don't have a good enough understanding of primary/secondary pipe lenghts and diameters to know which ones are better at which range with which engine modifications.

Sorry a long way around to say I dont know.

Paul
 

·
Member 1000 Post Club
Joined
·
1,520 Posts
Discussion Starter · #11 ·
Paint

It is the original color, Jade Mist Green, but not the orginal paint job.

Back in college (1980), the drivers door was scrapped and a week later someone else backed into the spot just behind the drivers door. So I had all the work repaired and paid the body shop extra to shoot the whole car.

The paint is probably not in as good a shape as the picture. You know digital pictures are.

Thanks
 

·
Member 1000 Post Club
Joined
·
1,520 Posts
Discussion Starter · #12 ·
Front Suspension

Here's a couple of pictures showing the polyurethane bushings in the front, with grease fittings, the lower control arm boxed, Coil springs from Coil Specialities 275#, and custom valved Bilstein shocks. I already owned the shocks, since 1978, so it didn't cost much to rebuild them and have them revalved, $55 each.
 

Attachments

·
Member 1000 Post Club
Joined
·
1,520 Posts
Discussion Starter · #13 ·
A few pictures of the rear showing poly trailing arm bushings with grease fittings and an adjustable PanHard bar (thanks Bob).

I took some of these at the muffler shop, so you can see they are just starting the exhaust.
 

Attachments

·
Member 1000 Post Club
Joined
·
1,520 Posts
Discussion Starter · #14 · (Edited)
Exhaust

Took a few pictures this evening after my camera got back from a camping trip with my daughter. Don't count this as the finished system. The guy at the muffler shop agreeed to raise the muffler a tad since is a bit low.

I used a DynoMax Turbo II and a Monza dual tip resonator. You will notice that I used mandrel bends as much as possible for the over-the-axle portion. I know Rally Bob recommends the straight thru type, he also says that 2 are needed on modified engines. I tried to get by with one @ less than $100, instead of 2 @ more than $100 each! The one I bought has internal flow directors, which I thought might keep keep the HP losses to minimum. Also, I thought this muffler would be quiter than the straight thru type.

Well the sound is quality is very good, but its a little louder than I would have liked. Back in my teens or twentys, it would be fine. It has that loud resonance/drone from 2200 to 2500 RPM, that I was dreading. Above that it really quietens down a lot. Cruising at 3000 RPM, you hardly even notice it.

Sounds great at idle and just revving it while sitting still too!

Keep in mind, I've been driving the car with only the carpet and drivers seat in it. I have NO headliner in it, back seat and the rear windshield is out as well. Hopefully, it will quiten down a little more when the interior is installed.
 

Attachments

·
Registered
Joined
·
2,894 Posts
Paul, I really like the addition of grease fittings. I wish I'd thought of them when I started my rebuilding of the front and rear. It looks very good. What type tires are you running on it? I really like the tread pattern. Jarrell
 

·
Member 1000 Post Club
Joined
·
1,520 Posts
Discussion Starter · #16 ·
The tires are Bridgestone RE 950s. They have very good dry traction with little drop off in the wet. The compound is softer near the base of the tread. In hot climates, they seem to wear a little faster than cooler climates.

Check www.tirerack.com for driver feedback on them.
 

·
Member 1000 Post Club
Joined
·
1,520 Posts
Discussion Starter · #17 ·
Grease Fittings

On one of my several purchases from Eastwood, I found some plastic covers for grease fittings. I "thought" I'd put them on ALL of the fittings. I notice from one of the pictures, that I missed the fittings on the lower control arms.

The caps were available in Black or Red. I chose black, therefore the caps make the fittings a little hard to see in some of the pictures.
 

·
Opel Addict Since 73
Joined
·
358 Posts
Inspirational!!

Paul - Your posts have been inspirational. I bought my current 75 Manta from the original owner and your story is almost identical to his. It was his daily driver until about 10 or 12 years ago. He parked it in his basement and intended to restore it eventually. He started it once a week until the battery died and then it just sat until I bought it two years ago. Unlike you...the original owner was an older gentleman and didn't have the time or motivation to restore it so he decided to sell it. (he still comes to see it at Carlisle) Fortunately...he took very good care of the car and the drive train required little work apart from cleaning out all the old fuel and replacing all the rubber. This is the Manta I wanted for years...minus the sunroof (75 with manual and A/C) The paint is original and is in remarkably good condition. The only thing I need to do is repair a small rust spot on each fender. I've been slowly gathering the parts I need to improve performance with the original injection (flat tops, cam, valves, etc.) and I've been planning some of the same upgrades you've done. Sadly...it now looks like I'll be relocated out of the country and I won't be able to bring my Manta with me. So I may have to depend on the enthusiasm of my youngest son to do the work...or sell the car. Either way, I'm grateful to you for posting your labors of love for the rest of us Manta fans.
 

Attachments

·
Senior Contributor
Joined
·
730 Posts
SW75, hopefully your not going to camel-land (Nasty place)? Let your son do what he can and learn the love of Opel! :)
 
1 - 20 of 60 Posts
Top