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LS-1 MGBGT aka PROJECT GINSU

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NOHOME P P
O, Ontario, Canada   CAN
1967 MG MGB GT "Maggie (GT From Hell)"
Just being the devil's advocate here, not beating on your plan, but since you plan to widen the shell anyways, have you given some thought to using the entire BMW donor under the MGB GT shell?

The work saved doing the front and rear suspension mounts not to mention that it would be done to BMW factory standards, would be a huge plus.

The tunnel, firewall, floor, seat mounts, seat-bels and all HVAC and dash controls could be kept as modern BMW stuff.

Here is a guy who is doing the BMW chassis under his Volvo 122. http://forums.turbobricks.com/showthread.php?t=333984

Where I think this guy is smarter than me is that he is keeping the BMW drivetrain. In fact, he made sure that the BMW was driveable right up to the point where he drives it under the Volvo body. At that point, I was still looking at a V8 conversion with the only reassuring bit being that the Miata V8 conversion was well documented.

You would have to figure where to section 17" out of the BMW floorpan so that it matched the MGB wheelbase.





The other reason for doing the BMW chassis swap would be because the road to converting a 325 to LS power is well travelled by Siki and Vorschlag who make well developed kits. Buy or steal the design as you see fit.



OR, recalibrate the project and drop it on a Miata subframe since the wheelbase is the same as the MGB and the LS engine swap is equally well developed by V8 Roadsters. This chunk of Miata would fit right under your MGB GT puzzle piece. You could have the option of leaving the Miata drivetrain in and doing the LS conversion after the rest is done or do it at the same time.



Like I said, just spitballing here, looking forward to seeing where you go with this project.



Pete

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bills Avatar
bills Bill Spohn
W. Vancouver, , BC, Canada   CAN
I like your thinking outside the box, but....the usual BMW chassis have a wheelbase of around 107" while the MGB has one of 91" - that's too much to 'lose' without shortening the tub.

One possibility would be a Z3 with just under 97" That's 3" you need to lose at each wheel opening. Possible.....not sure how to best accommodate that difference, though. Lots of room in the engine bay for whatever you like - this is a Z3 that the factory did as an exercise - BMW V12. Track width is 56-58" vs. around 48" fo MGB but that would be taken care of when widening the MGB body.





Bill Spohn www.rhodo.citymax.com/carstuff.html
Current: 1958 MGA Twincam (race car (170 bhp)),1962 MGA Deluxe Coupe (98 bhp)
1957 Jamaican MGA (200 bhp)1965 1971 Jensen Interceptor (350 bhp)
2009 Pontiac Solstice GXP Coupe (350 bhp)
2007 BMW Z4M coupe (340 bhp)
Recent: 1969 MGC roadster (175 bhp),Jensen CV8 (375 bhp),
1969 Lamborghini Islero S (350 bhp), 1988 Fiero GT turbo (300 bhp)
North Vancouver BC

NOHOME P P
O, Ontario, Canada   CAN
1967 MG MGB GT "Maggie (GT From Hell)"
Bill:

I did mention the 17 inches that needs to come out of the BMW chassis. I would think that a few minutes with a sawzall in the back seat area ( needs to be deternined exactly where to cut cause I got it wrong the first time ) would take care of this. Certainly preferable to the ordeal I went through to make the Miata 7" longer.

The reason I mention it is because he already has the donor. He needs a mounting structure for the front and rear suspension. He needs a transmission tunnel for the T56 and he needs a firewall and seat mounting structure. So he is pretty much going to go to all the work to fab up what BMW has already done. Plus fuel deliver and hydraulic routing is all done. Just splice what you cut!
And we know that LS engines fit in BMW 325s.

Pete

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bills Avatar
bills Bill Spohn
W. Vancouver, , BC, Canada   CAN
If there is an easy way to shorten the BMW, I don't see any downside!



Bill Spohn www.rhodo.citymax.com/carstuff.html
Current: 1958 MGA Twincam (race car (170 bhp)),1962 MGA Deluxe Coupe (98 bhp)
1957 Jamaican MGA (200 bhp)1965 1971 Jensen Interceptor (350 bhp)
2009 Pontiac Solstice GXP Coupe (350 bhp)
2007 BMW Z4M coupe (340 bhp)
Recent: 1969 MGC roadster (175 bhp),Jensen CV8 (375 bhp),
1969 Lamborghini Islero S (350 bhp), 1988 Fiero GT turbo (300 bhp)
North Vancouver BC

NOHOME P P
O, Ontario, Canada   CAN
1967 MG MGB GT "Maggie (GT From Hell)"
The critical measurement that I learned is to measure from the front axle to the middle of the front seats. The donor and recipient should be close if you want the driver ergonomics to all land where they should. Also side to side as you don't want to be sitting behind the a-pillar if the donor is too wide.

And now that you mention it,THAT is where my plan falls off the rails. The OP is NOT going to widen the window aperture and there is a possibility that the drivers seat and pedals are going to be too far outboard for this to work within the MGB GT windshield opening.

Pete

mgbgts Avatar
mgbgts Rob Meier
Johnstown Ohio, USA   USA
After finally deciding exactly how far I can move the sides out ( my original thought before cutting was 1 1/4 inch and that's what it ended up) I tacked in tabs along the cut line and a strip in the heal board to hold everything secure. I decided the edge of the roof and the inner structure around it would likely prove to be a bit of a challenge, so I started there. I tapered the edge of the roofline in above the drip rail, that effectively lowered the edge, meaning I can get a good line without raising the roof any. After a bit of thinking, a little cutting and some tweaking here and there I started filling in the rear upper roof rail and I'm pretty happy with how it's going so far.


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Jim Stabe Avatar
San Diego, California, USA   USA
Seems like a whole lot of work for very little increase in width. If you are going to all the work to widen it you should consider going much wider so you can cover the suspension and drivetrain without ridiculous looking flares.



Jim

"If you want me to agree with you then we would both be wrong"

'66 MGB widened 11" with supercharged LT1 Chevy and 6 speed, C4 Corvette suspension
Pictures here Part 1 http://forum.britishv8.org/read.php?13,7581
Continued in Part 2 http://forum.britishv8.org/read.php?13,22422
Continued in Part 3 http://forum.britishv8.org/read.php?13,33108
Continued in Part 4 http://forum.britishv8.org/read.php?13,40751
Continued in Part 5 http://forum.britishv8.org/read.php?13,48698,48698#msg-48698

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NOHOME P P
O, Ontario, Canada   CAN
1967 MG MGB GT "Maggie (GT From Hell)"
Flares should not be too bad. The new track is 7" wider and that is before you play with wheel backspacing. So after the tinwork, there will be 2.25" per side to cover worst case scenario. We wont be talking box flares here, nothing more than the Omni or Rabbit flares that are customary.

Pete

Mark C Silver Member Mark Cross
Marysville, Ohio, USA   USA
I have a GT shell that is going to go to scrap, wondering if it my be a help to have some roof, pillar pieces that could be grafted in that already have the correct shape? This shell is rusty beyond repair below the belt line. Whatever you can use, is yours for the taking.

Mark..

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mgbgts Avatar
mgbgts Rob Meier
Johnstown Ohio, USA   USA
Heck, the whole inspiration for the project when I dreamed it up 20 yrs ago was to build a GT with ridiculous flares of a specific style that I envisioned and I didn't see anyone else doing grinning smiley

The 2 1/2 " I'm adding to the shell is to the get the rear rails the same width as the BMW rear rails, give me a little extra clearance in the engine compartment, more seat options, make the rollcage a little less intrusive (the front upright bars should now tuck neatly behind the a-pillars too), and of course to do something different than I was seeing others doing (more on that later as the build progresses)

The flares are going to be around 3 1/4" with exact measurement depending on final wheel selection

Mark, I appreciate the offer, but I do have another crappy shell sitting out back for the roof (if I need it)

bills Avatar
bills Bill Spohn
W. Vancouver, , BC, Canada   CAN
In reply to # 3653932 by NOHOME Flares should not be too bad. The new track is 7" wider and that is before you play with wheel backspacing. So after the tinwork, there will be 2.25" per side to cover worst case scenario. We wont be talking box flares here, nothing more than the Omni or Rabbit flares that are customary.

Pete

Assuming for the sake of argument that there is no offset on the wheels, and that half of the wheel will go out and half in, and that you use wheels of similar size to the stock BMW chassis, then the wheesl would stick out 4" on each side on top of the 3.5" that the track adds. So 7.5" less any negative offset the wheels might have (not sure what you assumed in your calculation). Did I do that wrong? Just wondering if your figure was right.

Still, it might not be too bad - this car uses 8" rims, about the same as the BMW and looks pretty good.,





Bill Spohn www.rhodo.citymax.com/carstuff.html
Current: 1958 MGA Twincam (race car (170 bhp)),1962 MGA Deluxe Coupe (98 bhp)
1957 Jamaican MGA (200 bhp)1965 1971 Jensen Interceptor (350 bhp)
2009 Pontiac Solstice GXP Coupe (350 bhp)
2007 BMW Z4M coupe (340 bhp)
Recent: 1969 MGC roadster (175 bhp),Jensen CV8 (375 bhp),
1969 Lamborghini Islero S (350 bhp), 1988 Fiero GT turbo (300 bhp)
North Vancouver BC

Mark C Silver Member Mark Cross
Marysville, Ohio, USA   USA
In reply to # 3654039 by mgbgts Mark, I appreciate the offer, but I do have another crappy shell sitting out back for the roof (if I need it)

I kinda figured you would have one already or access to one.

Mark..

Jim Blackwood Avatar
Jim Blackwood * BlownMGB-V8
Gunpowder Rd., USA   USA
Rob, as far as I can tell from your photos the lines do look good, and the 1-1/4" extra at the A pillar shouldn't get in the way too much. I hear you on the flares, I also developed my own unique style of flares, and in fact so far as I am aware I did it well in advance of the first use of Rabbit flares, back about 1980-81 actually. I used them on my car and later on the MG-Roadmaster, rear only, and also developed a method of widening the front of the car that didn't use flares, by adding a wedge of sheet metal to the top of the fender in the dip adjacent to the hood line. I like a more rounded and contoured appearance that preserves full suspension movement, and that isn't really effective with Rabbit flares if more than minimal width is added to the tires. If someone is even a little competent working with sheet metal and is willing to take a few chances you can get very creative. Having some spare body parts on hand makes a big difference of course, especially when you are not relying on the car for transportation, like I was at the time. 3" of flare at the rear is easily achieved without resorting to a "boxy" appearance.

On both ends I'd recommend you pay very close attention to wheel offset. Not sure what you will have there to work with on the BMW suspension, but I know on the MGB if you go to a larger wheel diameter it opens up more possibilities with moving the tire inwards. In particular I have found a lot more room under the front of the car than I expected to, and I have radically revised my opinion of the need for front flares as a result. I know people think that the flares need to be balanced front and rear, but with suitable rear flares it may not be desirable to flare the front at all in many cases.

The rear is limited to the width between the unibody frame rails, it is difficult to go inboard of those even with alternative suspensions. On the front the limiting factors are more complex but essentially consist of the rub areas between tire and inner fender, usually the bulge above the shocks, though the swaybar also gets in the way a little.

Jim

mgbgts Avatar
mgbgts Rob Meier
Johnstown Ohio, USA   USA
Just a small update this week. I've been out of the shop sick for the better part of 6 days ( I can't remember the last time I was down that long), so all I managed to get done was to finish piecing together the rear inner roof rail



Edited 1 time(s). Last edit at 2018-01-06 03:12 PM by mgbgts.


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mgbgts Avatar
mgbgts Rob Meier
Johnstown Ohio, USA   USA
For the left side, just rinse and repeat what I did on the right side


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