M Roadster Suspension Swap Text Teaser

[Derek 350i]

Well, after a few months and more money than I care to think about, my final M Roadster suspension conversion pieces are on order, and should be arriving in the next two weeks. I will be taking plenty of pictures of the conversion and will document it and problems encountered along the way.

Here is the list of parts:
M Roadster Front spindles
M Roadster Trailing arms
Powdercoated e30 rear subframe crossmember
e36 M3 Bilstein Front Sport Struts cut for Ground Controls
e30 M3 Bilstein Rear Sport Shocks
Ground Control Springs 450# front 650# rear
Ground Control Camber Plates
Ireland Engineering Urethane Subframe Bushings
E30 M3 Offset Control Arm Bushings
3.73 LSD
e36 Tie Rods
e39 7 spoke wheels + spacers
e32 750il Master Cyl

After I get all of this on, I'll be putting on the Ireland Engineering 25mm front and 22mm rear sways.

[Digitalwave]

Sounds awesome man. But if I recall right you are doing the small block V8 swap to save money right? Well with all that money your dropped on suspension, I'd guess you have plenty for an S50 swap instead

[Derek 350i]

I could have bought an S50 engine and tranny for what I have in my suspension, but I would have blown out my 4 cyl diff, and still had worn out shocks and mounts, brakes that needed replacing etc... Also, I am looking for more than 240 hp. With good intake and exhaust, the LS1 is good for 345 to 350 hp at the crank. You can pick them up all day, with a t56 6 speed for under $4500.

[M-technik-3]

How much extra weight will the Chevy ls1 weigh in comparison between a s50? I know the advantage of HP/Torque that you will gain plus a nice lazy drivetrain ie low rpm for under 70 mph with your combo. Sounds as though you have been thinking this thru for quite some time.

[Derek 350i]

M-technik-3:
It will be "road legal", just not all that road friendly. No A/C, no interior, no radio, but will have cats, and full exhaust. Will be used for some track events.

I wish I had a definitive answer on the weight gain. The engine is 395# without accessories, but I will only be running a starter and alternator. I have been running w/o power steering for a while and aside from parallel parking I like it better. I am going to run a light weight composite hood, fiberglass front bumper cover, and fiberglass fenders if I have to in order to balance it out. Also, I will have a fuel cell mounted above the rear wheels against the back seat braces which will hold 70 extra liters of fuel. This will put some extra weight in the back end, at least when filled. I did a trial fit on it and it was like it was made for it. Oddly enough, it was actually made for a Ferrari 333sp.

Yes, I have been working this through in my head for quite some time. About all I have been sure on is v8 power. I have been (am??)waivering back and forth on which engine / transmission, to make the car behave like I want it to. The LS1/T56 will yield good power, great economy (1600 RPM at 60 mph), and will be low maintenance. An Ford/Tremec 5 speed would be higher strung, not so great on the gas, but a whole lot of fun. Unless a Ford / Tremec gets dumped in my lap cheap, it will be LS1/T56.

My biggest concern was having a suspension to handle the power, which I will soon have, so it is time to rebuild the budget for the engine.

[M-technik-3]

Tthe t56 isn't that a 6 speed unit? Just a t5 unit with another gear grafted on? My friend just put one in his 340 crate motor mustang with trick saleen parts.

[Derek 350i]

Yes, the T56 is a 6 speed. The 5th and 6th gear ratios aren't so favorable, other than for economy out on the highway. The Tremec TKO II 5 speed actually has much more usable ratios. With each shift, you pickup about 500 RPMs higher than you did in the previous gear. ie. the gear ratio drop from one gear to the next is about half of what it was the previous shift. But it would also mean about 2500 RPM at 60, a little bit buzzy for a v8.