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Discussion Starter · #1 ·
My '74 Manta needs shocks, so I'd like to go ahead and put something on that will enhance my handling. No plans to race it, but I will be doing suspension upgrades with bushings, etc. on it down the road (doesn't need them yet). Any recommendations? Part numbers would be good.

While on the subject, does anyone have recommendations on springs? It could stand to be lowered a bit for looks.

Thanks,
Todd K.
 

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"Shock"ing info .........

Hi Todd:
Great seeing you at Carlisle !
KYB's for the front: KG-4605A (for Nissan trucks)
I will check on the KYB's for the rear. You can use Rancho #9168 on the rear - 5 position adjustable - which are for Jeeps (front), but they are twice the price of the KYB's that I have on the rear of the Manta.
All of this info is courtesy of Duane Foley.

We'll have to try to arrange a PA, NJ meet this summer.

See ya,
Rick
 

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I have a set of rare Koni Red Shocks for the front ($125), and a set of A/C Delco performance Gas Shocks for the rear ($90).

The KYB gas-a-justs are great for the rear, but no longer available, mostly the Gabriels (I can get at $35 each) and Monroe LE ($90 a set) are whats left if you go with a stock fitment in the rear. Bob Legere has told me there is a optional way to go with the rear, I think its a Ford Thunderbird (2.3L Turbo) but not sure.

As for springs, cut station wagon springs for the front and rear work well. The station wagon springs for the front are the same as the Manta, its only the rear that are different. I have heard cutting the rear Station wagon springs and putting them on the front works well. You can just cut your Manta fronts if they are good.

Thats what I mainly do, I cut the Mantas front springs 1 coil, and put cut station wagon springs on the rear. I have a set of nice Station Wagon Springs for $125.

Charles
 

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Great info.. ! I didn't know of the Nissan one.
 

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DR Kirby,

I bought springs from Coil Spring Specialties, www.coilsprings.com. Before I decided to do this I bought a set of wagon rear springs and planned on cutting them and my front springs down a bit. My 75 Manta is not quiet back together yet, but its close, so I can't give you a picture of the lowered look. I'm told that my rates and drop should be close to the pictures of Samdog's Silver Manta. Once upon a time Rallybob had a picture in the gallery of this car.

If you decide to go the route of purchasing springs will need to get shocks with different compression and rebound rates to match/complement the new spring rates and drop.

If you decide to go the route of cut springs, I still have a set of rear Wagon springs that have not been cut. However, I did clean, prime (with Eastwoods rust block primer), paint (with Eastwoods chassis black) and Clear coat them. I'd be willing to sell them for the amount I have invested plus shipping.

To match my springs, had my old sets of Bilsteins rebuild and custom valved.

HTH
Paul
 

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Discussion Starter · #7 ·
If you go with cut springs, do you need different shocks than those mentioned here?
Also, on the nissan and rancho shocks, are there mods required?
GREAT info here guys...thanks again!
Todd
 

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I second that, also any specs on the custom springs so we can call and order them would be great too. Proves that even old hands at this can learn new things everyday ;)
 

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Charles, look at response #2 in this thread. The link there shows the specs that CoilSpring has on file for Opels.

Duane's Manta uses the 375/180 springs which were made by CoilSpring.

Bob
 

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Discussion Starter · #10 ·
Hey Bob,

Are there any ramifications that we should know about before taking this route? Limitations on wheel/tire combinations, etc.? Also, would the Nissan truck shocks for the front and the Rancho shocks for the rear work with this spring setup? Any modifications for the shocks required?

Thanks again,
Todd K.
 

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There's always an exception. Tell me your specific circumstances, as there's never a 'one shock fits all' application. Ride height, spring rate, wheel offset (it affects the motion ratio and therefore affects the true wheel rate), and usage (race, rally, street, etc.).

This is why I refrain from giving specifics to this list. What I recommended for Duane's Manta were shocks for his Manta, not for everyone's. So if someone trys the same shocks on his stock Opel, he immediately say's 'Bob's recommendation sucks...the ride sucks, handling sucks, they bottom out, etc'.
So I become the bad-guy because someone made an assumption.

However, if you can give me the true numbers I require, I quite possibly have already tried a similar combination before, and can made a recommendation.

Bob
 

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Discussion Starter · #12 ·
Car is a 74 Manta Automatic. I have no plans to change rear end, but may switch over to Getrag at some point since I have access to them. I also might go to a higher performance engine, but my stock engine still seems plenty strong. Bigger brakes are on the horizon ('75 brakes).

Tires will be 205/60/13s on 5" Libre wheels (I've heard this WILL work and I've heard it WON'T work). I'd like the car to handle better than stock but still have a decent ride. I'd also like it lowered a bit. Basically, I want it to be a little more fun to drive, perhaps to the point where it could be occasionally autocrossed. I'm open to suggestions. I don't mind a stiff suspension that allows me to drive it aggressively, but I don't want it so stiff that it's no longer fun to take on a road trip (like Carlisle!).

Since the car needs shocks and suspension, I thought I'd go ahead and get what I need so I don't have to change it later on. The same is true with my exhaust, so I'm going with the sprint manifold and 2" exhaust as a replacement.

Thanks to Bob and everyone else with the replies.
Todd
 

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As a quicker way of finding it (The Coil Springs website I couldnt find a list or anything)

Manta/Ascona
(stock is 135 front and progressive rear: 118-180)

200 front/130 rear - 1" drop front/ .5" rear drop rear
For a slight drop and firmer ride

275 front/170 rear - 2" drop front/ 1.5" drop rear
Most popular set C&R used to sell. Very streetable, big handling improvement.

375 front/180 rear - 3" drop front/ 2.5" drop rear
For street/race dual purpose use. Great handling.

500 front/200 rear - 3" drop front/ 2.5" drop rear
For racing use.

So using those four sets as a basis what shocks best match up for each set.

Personally I am in tune with the 2nd set.

Charles
 

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GoinManta said:
So using those four sets as a basis what shocks best match up for each set.
It only answers the spring rate and ride height question. There are other factors I mentioned, plus another important one, which is driver preference and driving style. And of course there's price....
 

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Discussion Starter · #15 ·
OK...do you have a front and rear spring/shock recommendation for the following:

Driver prefers that it maintain a decent ride but they want a significant improvement in handling over stock. Handling should be AT LEAST on par with a GT fitted with front and rear sway bars and poly bushings. A typical week for the car would be an occasional commute to work on curvy roads that puts a smile on your face. On weekends, he might occasionally enter it in some autocross events just to have fun (no expectations to come home with trophies). No massive suspension mods here, just stock sway bars, poly bushings, and a good spring and shock combo that allows for a more aggressive driving style. Does this give you a feel for what we're looking for? Rick mentioned the adjustable shocks..that would be great! One could dial in a more compliant setting for street use, but make it more aggressive if/when desired. Let's try to keep total cost for springs and shocks to under $500...does that sound reasonable?

Todd K.
 

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neuropel said:
OK...do you have a front and rear spring/shock recommendation for the following:

Driver prefers that it maintain a decent ride but they want a significant improvement in handling over stock. Handling should be AT LEAST on par with a GT fitted with front and rear sway bars and poly bushings. A typical week for the car would be an occasional commute to work on curvy roads that puts a smile on your face. On weekends, he might occasionally enter it in some autocross events just to have fun (no expectations to come home with trophies). No massive suspension mods here, just stock sway bars, poly bushings, and a good spring and shock combo that allows for a more aggressive driving style. Does this give you a feel for what we're looking for? Rick mentioned the adjustable shocks..that would be great! One could dial in a more compliant setting for street use, but make it more aggressive if/when desired. Let's try to keep total cost for springs and shocks to under $500...does that sound reasonable?

Todd K.
Yes, this is doable. I'd go with the 275/170 springs then. No problem outhandling a GT with this combo, even a modified one.....

I will have to look up the part numbers for the shocks for you. You'll also need to cut down the front bump stops BTW. Should cost about $240-$250 for the set of shocks. The springs......I'm not sure about the price.

Bob
 

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Discussion Starter · #17 ·
Awesome...thanks again for all the valuable info! We'll keep an eye out for those part numbers.

Todd K.
 

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Well a Manta already handles better than a GT with sway bars and poly bushings ;)

But lets assume...

#2 springs (275 front/170 rear - 2" drop front/ 1.5" drop rear)

15" tires in the 205/50 range

Rims with 37mm offset and 18-20 lbs.

Aggressive handling, but streetablitily is high on concern list.

That enough info ;)
 

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Todd,

Sounds like you would need to pick between option 2 and 3 in Charles' post above. 275# vs 375# front springs and related drops. I chose the set with 275#, 2" drop front springs. Sure wish I had it running so I could give you my feedback. Its been reported that Samdogs Silver Manta has this set, you might ask him about ride quality. You might ask Duane directly about ride quality of his set-up with the 375# fronts and 3" drop.

If you dig deeper in some of the older threads, you will find some great discussion from the Bobs, L & D. In the discussion, it was mentioned that when the rear suspension is lowered, the Panhard Bar needs to be shortened to prevent the rear axle from being shoved to one side. Bob L gave a description of how to fabricate an adjustable Panhard Bar. Well, when making mine, I ended up with enough parts to make TWO. So I have an extra, complete with a chromoly rod end to the axle mount and polyurethane bushing to the chassis mount. Pictures are available.

Also, if you go with lowered springs, you should reduce the height of your front bump stops. Bob suggested to me to cut them at least in half.

Personally, I'd be very confident that whatever shocks Bob suggests, you'd be happy with.

Paul
 

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Discussion Starter · #20 ·
Paul,
Sounds like a plan. You can email me privately at [email protected] regarding your spare panhard rod...I'm interested. I've read about and heard about this before (even saw the plans once upon a time). I'm sure it would be easier for me to buy your spare setup versus finding and building my own.
I'll also look up Duane (should have talked to him more about this at the show).
By the way, what shocks are you going with on your car?
Todd
 
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