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Discussion Starter · #1 · (Edited)
hello, i have one of 'those' questions. i want to do a 4 cylinder n/a or turbo engine/trans swap from a more modern car into my 71 gt.

i have a full machine shop, and am an experienced welder/fabricator, so getting it to 'fit' won't be a problem.

i need some advice on what car to use as a donor. i think it needs to be a front engine/rear drive car. and i would like to keep it german. BMW 6's too big...Mercedes, too heavy and expensive...AUDI/VW 1.8T, maybe, the exhaust and intake are on the same sides as the gt, the size looks good, but audi/vw doesn't make a rear drive trans, only fwd or awd, any body know how to fix that? is the rotation of the engine correct? but with 150hp stock and tuneable up to +225hp, it would quick.

there are alot of japanese options out there. the mazda miata 1.8 looks really good, 130hp stock, tuneable, rwd setup, etc...but the exhaust/intake are on opposite sides as th gt's. do you think there is room? i could modify the pedal housing some...

other ideas were a nissan 240sx (150-180hp) the exhaust/intake are correct, but the engine seems awfully big for the gt's engine bay. honda s2000 would be perfect, but too much $$$$. any mitsu ideas? maybe some domestic ideas?

anyway i would like everyones input on the siduation...

thanks,

Jon

(i tried to attach a photo of the audi 1.8T , and the miata 1.8)
 

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crazy opeler
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Wow I wish I had a full machine shop.......

The audi sounds cool, car companies tend to stick with one bolt pattern so maybe they make a euro only car that is RWD?

I like the honda Idea, plenty of options for hop up, the crossflow heads are only an advantage, I believe that the Itake would be on the correct side and the exhaust on the other, you would need a custom exhaust anyway so that option would really create no extra work.

There was a guy on here recently who was starting a Miata engine swap but I believe that he never finished it. He did say that it was an easy fit. You can find wrecked miatas on ebay for under a grand, so this might be a cost effective alternitive.

Also you might try the RX7 rotory motor, less weight, more power, and plenty of room for hop-ups, the only downside is that they arent rebuildable.

HTH

Chris
 

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Jon,

I am in the midst of swapping a GM 60 degree V6 into my Opel GT, but I had seriously considered a 1.8 from a Miata.

The Miata has a superb gearbox, and makes decent power right out of the box, but what really made me consider the Miata swap was the availability of supercharger and turbo kits right off the shelf. From what I have read, these kits allow the 1.8 to make an easy 200 hp.

Plus, the Miata engines are still in production making for great parts availablility and aftermarket suppport.

Nathan Acree
Albuquerque New Mexico
 

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Hey Nathan...

We are practically neighbors (Colorado/New Mexico). I am leaning towards doing a GM 3.4 in my GT next year. I would love to talk with you and get info and pictures of your project... I too am considering the 1.8. What made you finally choose the V6?

Drop me a line sometime if you would... [email protected]

1. What production year is your engine? Is is a 3.1 or 3.4?
2. Where did you get it? What did it come out of? and what did you pay?
3. Are you fabing a new engine cross member?
4. How are you integrating the wireing harnass?

Info please!
 

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boomerang opeler
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hi, why not stick with gm. In europe we have what i think gm in the us call a "j" car we call it an opel vectra. the 2 litre twin cam efi puts out 150 ponys &can chip to 220 with no problems. as a plus it will also go on to the manta 5 speed box with just the prop to shorten. over the winter im putting V12 from my dead jag in to my gt ,i'll post some pics soon (you should see how much metal needs to be ripped out its almost enough to offset the block)
 

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I don't have a lot of time at the moment but I can give some brief answers ;)

1. The 3.4 I am using is a from a '93 F-body (ie camaro or firebird)

Camaros/Firebirds came with 2.8

2. The engine was acquired at a junk yard for $400- I got a really good deal

The trans I am using is a T-5 from an '87 S-10 with the 2.8 v6.

3. Yes, I have made a new cross member, see pictures at:

http://mywebpages.comcast.net/nacree/images

4. Wiring has not yet begun.

I am sort of in limbo on this project for while I sort a few things out, but the engine and trans have been mounted and connected via a custom (very short) driveshaft.

Basically I am integrating aftermarket AC into a custom dash and I have not had the time or workspace to get these things finalized yet.

Stay tuned I have a web page in the works and as soon as I have more content I will publish it.

Nathan Acree
Albuquerque New Mexico
 

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Sorry, in the above post I wrote

"camaros/firebirds came with 2.8" and I was interupted while I was writing that message and did not finish that thought.

What I meant to say was that camaros/firebirds came with the 2.8 V6 and then the 3.1 in the late 80s to early 90s, and then they went to the 3.4. Either the 2.8 or the 3.1 would also be good in an engine swap, but the 3.4 has more torque and also has a lower profile intake manifold that is only two pieces as opposed to the three piece intakes of the lower displacement varieties.

Nathan Acree
Albuquerque New Mexico
 

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Here's the GM 4.3 that I was going to stuff in a GT. I bought the headers just for the flanges. Then I picked up the '51 Olympia and that killed that project.

BTW, Nathan, you can edit your posts by clicking on the "Edit" button at the bottom of the post.

<Speaking of editing, I'll lighten up the picture tonight.>
 

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Opeler
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Miata 1.8L swap?

I have been pondering an engine swap for a while: rebuild a stock 1.9L, another opel from ogts, mazda 13b, even the gm 60 deg v6. But i think i've settled on teh mazda miata 1.8L. Makes about 140 hp (as i recall), and has a 5 speed.

Has anyone ever done this? Is there any problem w/the gt's backend with this amount of hp, or can i leave it stock for teh time being? Hopefully i'll eventually upgrade the rear end and upgrade all the brakes to vented.

Any info would help.

Steve
70 gt
 

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Miata Transplant Thread Merge

I have merged these two threads. Could I ask that posters take a moment to search the forum before they start a new thread? But then, ask away!
 

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Actually it depends more on the driver. I've broken three rear axles with automatic trannys and Opel engines under 150 hp. And with a manual tranny and sticky tires, it'll fail regularly with as little as 120 hp if you drive it hard. At 200 hp, even with a limited slip, it won't last long.

When Opel went rallying with the Ascona 400, they installed a reworked rear axle with the guts from an Opel Commodore, and eliminated the torque tube altogether. This was with 240 hp initially, with phase 2 engines making 255 hp and phase 3 making 275. At 275, even the bigger Commodore axles began failing regularly.
 

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Yes. But then again, with moderate hp/torque going through a transmission's gear ratios, the torque multiplication is substantial.
 

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Discussion Starter · #15 ·
turbo engine swap

well guys, thank for the advice...i have decided on which engine to swap into my opel. I am purchasing a 87 ford thunderbird turbo coupe. (in complete running condition, from a ford mechanic, with a brand new factory turbo for $750.00) it has a inline-4 2.3 OHC turbo intercooled 190 HP engine...stock! you can easily ungrade this engine to 250 HP plus!!

i am doing all of this so i can enter the GRM $2003 challenge(http://www.grassrootsmotorsports.com), 250hp in a 1900 lb car should be a very hard car to beat!!

the thunderbird is also a rear drive car with a 5spd maunal. parts are cheap, and interchangable with the merkur xr4ti, mustang svo, and any 2.3 ford engine. these engines can survive upto 400 hp without any bottom end modificationsbecause of a forged crank, rods, and pistons.

the layout looks correct, the exhaust is on the pass. side where there is room. the intake is high on the driver side, i will mount a bigger intercooler in my OGTS air dam up front. http://www.35pickup.com/SVOengine2.jpg

check out these sites for ford turbo info

http://www.key-ideas.com/MerkurPage.htm

http://www.key-ideas.com/DG_KurTwo62502Update.html

i will update as i proceed...

Jon

attached is a picture of a very nice 2.3 turbo
 

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Discussion Starter · #16 ·
supra rear end?

i was also looking at using a indepentant rear from a supra, my buddy has a 84 for parts, it looks like it could work...will it hold the power? (250 hp/tq)

Jon
 

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Yea, no sweat. I know of one person locally who drag races a 1985 Supra and he's turning low 12's with it.

Oh, BTW, there's a group of about 4 of us who are going to try to assemble a Manta for the 2004 (not 2003) GRM Challenge. Should be fun, we're gonna try to keep it all Opel however (I know, we're asking for trouble). The Manta should do VERY well on the autocross however, and with about 220 hp will run fast enough to keep up with the big boys. The tough part is keeping the engine together with that budget
 

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Miata motor

I owned a 95 miata for awhile with the 1.8 and 5 speed. This motor is really going to need the supercharger or turbocharger to make you happy you went through the trouble of conversion. It is a blast on the highway, but in town and starting from a stop, you really see it's lack of torque. A Jackson supercharger is just barely longer than the GM A6 A/C compressor and would fit about the same area, just closer to the engine than the A/C did on the 1.9 Gt's. The other problem is the miata tranny is pretty long. Total distance from pulley to shifter is 52 inches.
It is a very compact motor and from my eyeball measurements might be able to work with the stock engine crossmember if modified. I like it's potential over the 3.4 GM, but I like the torque a whole lot better on the v6 is both are in stock fashion.
Oh, the other big plus for the Miata, is that the accessories are configured in such a fashion that the Air Conditioning Compressor will fit, I'm not sure that this is the case with the GM 3.4
-Bret

If anyone gets started on the Miata swap, let me know and We'll do it at the same time and converse to help each other along.
 

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crazy opeler
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This is in reply to Jon.hass comment on buying the turbo motor.

I seem to remember a few years back there was a thread about this motor on the classicopels list and I think that motor was found to be excessivly tall. You may have a problem fitting it into the gt engine bay. I could be wrong but the manifold does look tall.

Chris
 

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jon.haas - I too think that the engine in its stock form will require you to make custom engine mounts to have it sit lower. This really isnt a big deal... Many engine swaps require new engine mounts. Other than that have you measured the shifter linkage? Will it poke throught the stock GT console correctly? Sounds like a nice idea.
 
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