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Discussion Starter · #1 ·
I had owned an opel GT once before and wish i never woudl have sold the thing as by far it was teh best car ive very had and that was with all the messed up things and horribble makshift wireing i threw on the poor car.

But it got sold for a profit suprisingly. Bought a mustang and went nutty for 3 months totaled my poor car and lsot my license for years....

However in 4 motnhs im back driving again. By the way i have bene in only one wreck that i have ever caused and im not jsut some crazed guy runnign around.

Anyway so here i am with a completely destoryed body of a ** mustang GT. a built motor and trans and all the wiring.

Ive decided opels are the way to go. Who knwos why but they are just great cars. However 102 horses aint gonan cut it anymore.

ive breifly looked into v-6 conversions and althoguh they look interesting and may make neoguh power(althoguht that is debatable) I allready own i belvei nearly evreythign i need to put the motor and trans in.

I read on a huge big blcok chevy being put in opels but this is not nearly taht big of an ordeal i woudlnt think. I knwo the driveshaft will need ot be cut and ill probalyl replace to rear end. The bigger problem i can see if more whre the engine and trans will line up once installed and will i have to move the engine too far up to have the trans in a decent position to use.

More then likely i will use space saving compnents as much as possible. such as thinner radiotor and electric fan and more then likely some block hugger headers but thatll only do so much.

I woudl love any thoughts on this and ways to go abotu finding the correct dimensions and locations i woudl need. I no longer have my opel to measure so im kinda guessing.

Also a possible cost estimate if allt eh work was done myself or for very cheap. Remember i have the engine tranny and all wiring.
I am goign to aim for around 350 horses at the rear wheels.
 

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First off, plan on a completely different rear-end, my V-6/T-5 may tax it more than it can handle and a 5.0 will surely rip it apart. Don't go to a thinner radiator, thicker is much better, even a 4-row if you can find one. The radiator measures about 14-15" of core, not counting the upper and lower tanks. You may want to opt for an S-10 tailshaft on your tranny, if you have the T-5, it will put the shifter almost centered in the hole, using the rear auto tranny mounting holes, But you will have to relocate the subframe pad to the tranny mount back 2 1/2 inches. The footwell and wiper well will have to be cut for sure, I'm not sure about the heater box on the other side of the car. Because the car is a unibody, it may not be able to withstand the torque of a built 5.0 and may require an extensive amount of re-enforcing to keep the twisting action on the body to a minimum. I'm not saying it can't be done, but it will take a whole lot of work. Just my $.02.

Ron
 

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I agree with what namba says

You can also have the car frame wrapped / strengthened the same way people do that to cadilacs to have hydrolics on them

V-6 with large pistons and super charger is the way to go.

Save space. Much more than v8 also check this out

A 3.8 chevy v6 cranks out 200 hp stock 98 camaro
A v8 chevy 5.0 cranks roughly 170 off a 91 camaro.

figure weight distribution it would be like 70/ 30 with the v8 dont sound to good.

I may be wrong but these are the first things that come into mind
 

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Discussion Starter · #4 ·
And some more questions

Allright here is the plan.... Tell me estimated cost and time if work is performed by myself. Thanks

I find a narrow framed car cut and weld it to what would be more or less the original dimensions. Install a fairly lame 4 point roll cage. attach my 88 mustang front end pieces and read end to the frame. Now i know the width will be to much so it comes to i will actually widen the oepl fenders 2 inches on both sides. I understand they have flares for sale. This will also allow a easier fit for the engine as well.

Now here is the problem

Maybe
in reality due to the fact the tranny will be in the middle the real weight effect wouldnt be that much diffrent would it?

ALso remember aluminum heads and intake and no air conditioning. Thats over 100 pounds of weight there. the rear end will be heavier as well putting more weight back there?

In reality i only think that it may add anotehr 100 -150 pounds max up front???? Also the roll bar will be in the center and back.

Now i havent measured the width of an opel or the width of my stang but i wouldnt think it would be 4 inches wider.

What do you guys think or if you have numbers that would be great to. Any thoughts are appreciated.

If all that will fit would that realyl be fairly cheap but tiem consuming as no parts or machining woudl be needed besides a driveshaft?
 

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dont be discouraged

Sounds like it will work and i ope it will for you.

Let me use me as an example
I tried to follow nambas way on the v6 conversion too costly for me being that im young and have liitle mechanical skill however if i could i would go exactly the way he did. I just about gave up hope and was gonna trash my car when

I found a guy who was shopping at walmart told me he owned a race shop and said yeah i can make custome stuff well he is in the process of making my tranny mo unt which is good news

then ill have him make motor mounts similiar to the opel originals then ill be set.


So keep trying ask around check shops pitch your idea they may say it will work.

Its not like people havnt done it before.

I have heard of a guy around my area who put a vett engine in his opel a lot of work but the point is he did it.



:D
 

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In the past 6 months I remember seeing maybe 3 opels that had roll cages and some what reinforced frames sell on ebay for next to nothing. and the engine and transmission will weigh quite a bit more than your thinking you can pick up an opel transmission with one hand easily. I think a 305 block weighs close to double what an opel block weighs. the front end will have to be beefed up to compensate for the extra weight. since your trading out frames the geometry and measurements will have to be dead on or else the car will ride funny at high speeds or track to one side at slower speeds, thats if the wheels ever stop spinning. the car only weighs a little over 2100 lbs there just simply isnt enough weight for it to get some traction with all that touque. speaking of torque if there isnt enough flex in the frame stress cracks will evolve and eventually something will break. also with the extra torque and the same rack and pinion steering system It will handle terribly..can you say torque steer? I'd say if your not happy with the 1.9 the better solution would be is the v6 conversion...much easier all you have to do for mounting is alter the engine cross member! that will have tons of torque and hp and will be much cheaper any way you look at it. a v-8 in an opel is like a GE CF34 turbine jet engine on the wright brother's plane.
 

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v8 in an opel??

i believe that the only really good way to put a v8 in an opel is to build up a tube frame, complete with engine and trans mounted, then lower a gt body onto the frame. of course, this isn't really an opel anymore, but...

the only v8 conversions i've heard of are drag cars, built especially fr drag racing. a stock body will not stand up to the abuse of a v8. stick with the v6 that namba talked about. it is proven, and will work. it will take some doing, but you will be quite satisfied with its' performance. the car only weighs 50 pounds anyway, so 200 hp will be quite sufficient.

good luck either way.

mike
 

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maybe just not on a GT

I know the GT is "sexy" looking and all that, but the Manta actually has enough room between the frame rails to install a 5.0 Ford without any cutting. It also handles much better and tends to be a cheaper car to find, both of which are good things. Food for thought.......

Several companies make complete 12 point roll cages for the GT, some kits being less than $400. Add a set of rails underneath to connect the "subframes" and you might have a solid enough car to handle the 5.0 for a while. Since the weight balance will be all off and the handling terrible anyway, might as well just put any old axle in with a ladder bar set-up. You might also consider just cutting the entire front of the car off, adding a whole new front suspension and a 1-piece fiberglass front-end.

It's not that it hasn't been done, or that we all hate the idea, the issue is that that radical a surgury makes the GT impossible to return back to stock. Add to that that 95% of these things tend to not get finished, and all most guys end-up doing is destroying another perfectly good GT. I've even driven a 327 Chevy equipped GT convertible once, with the stock rear-end even. It was fun, but unfortunatly the car was probably bound for the scrapper 'cause he couldn't even get the money he had into welding rod back out of it.
 

· Old Opeler
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Too Narrow

The only V8 that goes anywhere near fitting the GT engine bay is the Buick/Rover alloy engine. It is close to the same weight as the Opel Cast Iron Lump and quite narrow by design. It fitted into the engine bay of the Rover P6 Sedan which originally had a 2litre four cylinder engine when all said and done!

The Rover V8 can be punched out to around five litres too. With the Buick 300 CID engine crankshaft fitted and using bigger cylinder sleeves with 305 Chevy pistons.

I have both Rover P6s' and a GT and looked long and hard before deciding to retain the Opel four cylinder motor upgraded to 2.2 litres - with 305 Chevy pistons (half a set!).

I'll keep the 5 litre V8 for the Rover so it will be able to keep up with the 2.2 litre GT:D
 

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don't destroy a gt!!

i agree with oldopelguy...most radical conversions probably don't get finished. another gt bites the dust.

this site is about preserving the breed so that it will be around for another geberation or two. i would like to think that my kids could be driving a gt if they wanted to, and this site and others like it are a good way to help that happen.

do what you must with the 5.0, but try to leave the car as stock as you can so that you or your kids can have an original car if they want to.
 

· boomerang opeler
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jaguar V12 and running gear , tube chassis, roll cage, tubed rear to take jag axle and fuel cell (poss rear hatch to fit fuel cell)

this winter project only way to go with a big engine (only 28 inches wide)

and if you use the buick/rover engine you need a trolly jack to change the spark plugs as they are too far round the heads to reach unless you put 8 holes in the inner wings if memory serves me rightly
 

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Discussion Starter · #12 ·
As for my whole idea in reality what one of teh previous psot said was build a race frame with engine and tranny and all installed then lower the body. In all reality that i basically what would be done. the increased width of teh possible engine bay woudl be another 4-? wider remember as i will use my mustang rear end and all teh suspension and steering components.Naturally i will have to cut out some metel but rememrb all the suspension compnents are beign moved outward as well. Also i didn trealize it but a 2 inch flare istn really much and i could have more flare if i needed.

More or less the car will have a narrower frame then the msutang but will be wider due to teh tires sticking out wrapped by flares.
Hell i have subframe connectors on teh mustang now anyway and wouldnt be suprisedif i could damn near build a whole frame outta the car now. although it would be narrowed.

So Im basically hearing it will work ????
I dont see the huge amount of money sunk into this really. ALthough i do see large amounts of time. Also by using the comppents i allredy have that are all tehre and work little bits and pieces shoudlnt be a problem should they?

More then likely i woudl liek to have a fiberglass front end but not sure as to if i coudl afford it. So i am consdiering welding the hood and fenders all together and brace it and make it tilt forward so i can access teh engien easier.

All thoughts are appreciated.
 

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Discussion Starter · #13 ·
Also everyone has been referencing the 305 GM motor. This is a ford 302 block with aluminum intake and no AC and other weight saving here and there. Anyone realyl have any numbers ont eh weight of the opels tranny and engine or the mustangs?

Oh yeah and as for the front being to heavy for the suspension the point is its not the opel suspension its the mustangs....


Easily said ..... basically a mustang with a little more support(roll bar) with an opel GT body
 

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Ford 302 weighs about 425# with AL intake.
Chevy 305 weights about 550# with AL intake.
T-5 tranny weighs about 70# (by itself).
AOD tranny, with TC and fluid, about 190# (ouch).

302 is longer than 305, but much narrower. You'll need to move the radiator. Otherwise, it's a much easier fit. 302 has coil in front, a good thing.

People make assumptions based on displacement. A turbo V-6 may punish a car much more than a 302. Torque and HP control. You'll need a different rearend. Otherwise, you can't use the HP, what a waste that'd be. You also don't want to pop out all the glass and twist the body. A cage and careful reinforcement should work. Tube chassis is available under $1800, but you gotta install it.
 

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Discussion Starter · #16 ·
Wow thanks for the info on the weight diffrence also you save osmethign liek 50 pounds on swaping to aluminum heads as well. So thatlly brign the total down to 375. I mean i dont knwo but how much diffrence could that make compared to an opel engine? Also no air so remove some more weight. Also I have the T-5 tranny as well to clear that up. I dont knwo how much teh ol opel egnien weighs but i woudlnt be suprised it it was 250ish so how much can 100 pounds really make?
As for the rear end im using the 8.8 rear-end outta my mustang that has been beefed up as well.

Okay now that i belvei basicalyl the weight diffrence has been more or less overcome does anyone see other problems?

Does anyone know if the 4 inch wideining of the enigne bay will accept the Ford 5.0? or how much i need to clear out?
 

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sure, why not

Sure, if you open the engine bay by 4" or so a 5.0 should fit. The only problem with that is that the edges of the engine bay are what passes for a frame in the front of the car. If you try to make the engine bay any wider you WILL HAVE TO FABRICATE AN ENTIRLY NEW FRONT HALF OF THE CAR.

There is also nothing forward of the firewall strong enough to mount the top of the Mustang's front struts to (and I think they would be too tall anyway) or the lower "A" arms, or even the motor. No way struts are going to be easy to work with in the front.

In short, if the motor won't fit between the Opel's stock "frame" rails, which define the bottom edge of the engine bay, you will have to build a completely new chassis to put the Opel body on. It would probably be easier to get a Pantera transaxle and make it mid-engined. Then you only have to fabricate one new suspension.

Just another guy's 2 copper coins.
 

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Re: Too Narrow

GTJIM said:
The only V8 that goes anywhere near fitting the GT engine bay is the Buick/Rover alloy engine. It is close to the same weight as the Opel Cast Iron Lump and quite narrow by design.
Just to amplify this a bit, there was an article in Sport & Classic Car (UK publication) a while back that profiled a GT that had this swap done. Had some photos of the engine bay as well. Seemed like a very good fit, no major cutting was evident. Also, the claim was made that the Aluminum 215/3.5 V8 was actually LIGHTER than the CIH that was removed, and suspension adjustments were made to lower the front end back to orginal ride height. Seems like the best candidate IMHO for anyone dead-set on a V-8 swap

-Stephen M
 

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A small block Chevy is much wider and fits widthwise using rams horns exhaust manifolds. A Ford 302 (about 1.5" narrower) with narrow street rod headers should fit, EXCEPT, the heater must go and you'll need to modify the footwells (as required on all V engines). You'll also need a rear sump pan. Don't get me wrong - You'll be doing a lot of fabricating, pounding and welding.

You'll also need to finagle extra joints in the steering column shaft, and rethink the master cylinder and pedal locations.

It will weigh more and be more nose heavy. The 302 flywheel/clutch/bellhousing weighs as much as an Opel 4 speed, the T-5 is extra weight. Adding the extra reinforcing steel, you're about 300# more than stock on the nose. Reinforcing the existing steel is the heaviest solution but the easiest (compared to all new steel).

The bellhousing and T-5 are a bunch wider and taller. There goes the tranny tunnel. And the Mustang T-5 has a tail shifter, which is several inches back of the stock shifter. You'll probably want a truck-style tranny with the shifter on top.

8.8 rear-end outta your mustang must be narrowed close to a foot. I'd get new axles for $50 more. Mustangs and Opels have really different rear suspensions. You'll have about $2000 in the axle.
 
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