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Opeler
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Discussion Starter · #1 ·
V6 conversion subframe clarification

OK - I'm learning as I go. The way I understand it, the reason some of these guys are fabricating new engine subframe connectors rather than mod'ing the old GT subframe connecter is because the connector needs to be lower and a little wider, further forward than the GT engine subframe, to make room for the fuel injection and big intake on the camaro motor. I was considering following Ron DeLozier's article for the subframe (an article that was a huge help, by the way, thanks Ron). But I think Ron is a more skilled welder than I am. There's got to be 30 welds on that thing! I took the lazy man approach, just bending a single piece of 1X2 tubing. see attached.

See any problems with this approach? There are some tiny dents where the bar didn't bend so good, but I've still got to put the engine mount towers on it and thought I would gusset over then dent and fill it with weld anyway.

Thoughts?
 

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what a nice clean tranny and block looks shiny. wow :D

Looks like it would work. I really like your aproach very easy and my style lol.
 

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Sporqster's subframe question...

Sporqster,
The bar going across with the green spot on it ...Is that part of the device ? Does the bent portion face downward ? I am in the process of building a V6 subframe, and I am open for any thoughts as to simplification. Next question for anyone listening. Has anyone done side exhaust pipes on a G T ? Any advice....comments.....pictures ?
 

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Sporqster's project

Forgot to mention that I really like the Chevy Orange valve covers.....COOL . Why not do the whole engine, it would look like a small block in a Vete.
 

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How are you planninig to attach your frame? To the bottom w/ tabs out or to the inside of the unibody? My plan is to use flat 1/8 steel cut at a semi-local metal fab shop. Depends on the angle of the mounts, I guess. If I'm not misstaken, that's the same exhaust setup the 2.8 uses. You can get a oil filter mount that points down instead of back which may make things easier for you later on.
Just my 2c's.
 

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Opeler
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Discussion Starter · #7 ·
The bar is not part of the device sorry for the confusion - which isn't done yet (still got to weld the mount towers to it - working on it this weekend.)

as for mounting it to the car, I was planning on just drilling holes and using the same bolts that held up the stock connector. I wasn't going to do this, however until the last second - that is, after the engine is suspended in the air inside the car. That way I can so some minor alignment of the motor by where I drill my holes.

Obviously a work in progress.

Hey- I just got a new mig welder from Harbor Freight (all I had before was a crappy inherited stick welder.) maybe I can get this thing put together if I can figure out how to use it!
 

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MIG - Metal Inert Gas . . . GAS being the operative word here

Sporqster said:
The bar is not part of the device sorry for the confusion - which isn't done yet (still got to weld the mount towers to it - working on it this weekend.)

as for mounting it to the car, I was planning on just drilling holes and using the same bolts that held up the stock connector. I wasn't going to do this, however until the last second - that is, after the engine is suspended in the air inside the car. That way I can so some minor alignment of the motor by where I drill my holes.

Obviously a work in progress.

Hey- I just got a new mig welder from Harbor Freight (all I had before was a crappy inherited stick welder.) maybe I can get this thing put together if I can figure out how to use it!
Save yourself some trouble, go buy the gas kit for it right away . . . I waited WAAAAAAAY TOO LONG to do that. You'll NEVER lay a bead with flux wire like you will with solid wire and gas! Makes you a MUCH better welder IMMEDIATELY!
 

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Just a thought. You can make a "pattern" using 1/8" ply-panel as the Opel frame. Then set it on your bench, w/ 1x2's holding them apart. Lot safer for you and the engine, plus you have the walk-around view which may help in your setup. You know, like how deep to set the motor, angle of mounts, etc... Keep us posted because it's good for the rest of use who haven't started our own project yet. (I got two GT's to do. 1 stock and 1 modified).
 

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I missed this thread, when it first came up, I was at a dog show out of town. Anyway, a couple of things, first those are Fiero type manifolds and you need to check inside the ports and clean out the inside of them where one pipe slides over the other and it creates a lot of flow restriction. Also chek them real close for cracks around the flanges. I got a pair off e-bay that were cracked almost in half. The welding done on my subframe was done by a pro, not me, that I contracted to have the work done. He brought his portable rig to the house and after I had cut and installed all the pieces for the subframe, he tacked them in place, I took out the frame work and he welded it all into one solid piece, three times. Same for the tranny subframe. As I said in Phase II, I screwed up and had to redo the whole mess and used all the pieces I could that we already had done. It can be made a lot cleaner looking. The oil filter has to be left as is, if you try to mount it hanging vertically, the engine plates will be in the way, and the engine plates will have to be played with to clear the oil filter adapter on one side and the engine knock sensor on the other. If the foot well and wiper well have not been trimmed yet, you will not be able to get the engine/tranny assembly in to bolt up the subframe, even with the exhaust removed from the engine. I've got pics of what I had to take out on mine, if needed I can post them, but so far I may have to take out more, I'm still waiting on a custom exhaust to finish Phase III that documents what I did to get the engine finally installed. HTH.

Ron
 

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namba209 project

Hey namba, I asked the board once before, but no one responded, about using side exhaust on a G.T. Have you ever done it , or seen it done ?
 

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yup

It's been done before, and I might even do it with my GT is I do keep it long enough to need a new exhaust. I half-heartedly plan on running a Corvette muffler in the stock muffler location, as they have the "in" and the "out" on the same side of the muffler, then running back up to the front to split off and go to both sides. That way the exhaust would be decently quiet even if I just ran straight pipes down both sides instead of mufflers for ground clearance.
 

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I haven't seen it done, but Jim Marchitto of USA Opel has or had a GT with a 3.8 Buick V-6 on consignment and it has side exhaust. I believe it was on e-bay also. The description in the e-bay add said the exhaust got very hot after the engine had run for a while and that you had been warned. The original plan, for me, was to have my V-6 exhaust exit just in front of the rear tires, but after looking at the rear end, where the exhaust cut-outs are, I decided to go with the stock looking exhaust with chrome tips at the rear of the car. From the front of my engine all the way back it will be 2 1/2" pipe. I'll have to get mandrel bent tubing to go over the axle. That will mimic the original V-6 exhaust as far as the pipe size goes. I had side pipes on my van many years ago, but didn't like the flow restriction caused by the two 90 degree bends required for the application of side pipes. JMTCW.

Ron
 

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Side Exhaust

What about some of those small diameter motor cycle mufflers. Wouldn't they be sufficient for side mounting ? Some off of one of the 750 or larger engines ? Back in the 70s Mopors ran the exhause back to the rearend housing, and then turned them back to exit at the front of the rear wheels.
 

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Motorcycle mufflers won't flow anywhere near the CFM that even a box stock 1.9 needs from about 1/2 throttle and up. That would be great for night cruisin' down Main street USA, but impractible for the road.

Ron
 

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Opeler
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Discussion Starter · #17 ·
I've got updates & OFF TOPIC - sorry been out of town

Wow - you go out of town for a weekend, and there's a bazillion replies.

BTW, though OFF TOPIC, thought I'd mention what I went out of town for - the North American Auto Show in Detroit. Wow. What a show. This was my first year to go to the big show, and for the most part I was pretty impressed. Of course, I was a little disappointed by the Subaru display - they weren't even showing an STi there - what gives? I also had some hopes of seeing the Elise that I thought was coming to the states, but not a single Lotus to be seen. I did, however, take a long look at the Pontiac Solstice. That'll be a pretty hot car if they can keep the price 20-ish like they're saying. Got to see the new vette - as with almost every new car design shown this year, everything old is new again. At just the right angle you can't miss the C3, Opel GT inspired heritage of the new Vette. The new headlights, however, look very Ferrari knock-off to me. (I'm really not a big fan of the NSX's new headlights either.) What's happening to hide away headlights? They seem to be a dying breed.

OK - back on topic...

I DID complete my motor subframe - pics to be taken tonight. I went ahead and invested in the gas shielding kit for the mig welder and found that once you've got the equipment set up right, the welding is really a snap. My subframe is probably a little bit over built. I've gusseted the crap out of it as you will see - mostly because I was having so much fun welding I just couldn't stop attaching braces ;-)

I owe you guys pics tonight.
 

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Re: I've got updates & OFF TOPIC - sorry been out of town

Sporqster said:
Wow - you go out of town for a weekend, and there's a bazillion replies.

. . .

OK - back on topic...

. . . I went ahead and invested in the gas shielding kit for the mig welder and found that once you've got the equipment set up right, the welding is really a snap. . . . :)

I owe you guys pics tonight.


Originally posted by tekenaar
Save yourself some trouble, go buy the gas kit for it right away . . . I waited WAAAAAAAY TOO LONG to do that. You'll NEVER lay a bead with flux wire like you will with solid wire and gas! Makes you a MUCH better welder IMMEDIATELY!
Glad to see you took my advice . . . TOLD YA!! :D
 

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Opeler
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Discussion Starter · #19 ·
Pics as promised

As you can see, I decided to catch the bolt up in the engine compartment with the steel plate - my bends were also a little too generous radius - requiring me to weld in spacers so I could get a nice flat surface to torque the bolts down on.
 

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A couple of things here, are you using the original bolts on the subframe or did you get longer ones? I noticed you did not put 1 1/8 holes in the bottom of the crossmember so the bolts are snug against the inside of the member. Second, I'm taking out the driver's side strap that bolts to the inside footwell, it's in the way of the 90 degree fittings needed for the oil pressure transmitter to the gauges. All in all that's a good looking setup, but I see you didn't pick up the two inside bolt holes on the frame. That is where a lot of the engine weight will be transmitted to the body of the car. There may be a fair amount of flex in that area. JMTCW.

Ron
 
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