500/560 SEC Project advise.

[Red C220]

I know little about SECs but had no idea the 560 put out as much as 300 bhp in stock form?

The Euro spec 560 motor was rated at 220kw or 295hp stock.

 

[GT500E]

Having owned a 560 sec the 300hp it made standard was quite a handful. It really isn't going to handle much north of 380hp to 400hp without major modification and I'm just not sure it's the right car for so much power. It really is a cruiser and not a sports car.

I hear what you are saying here. I realise the chassis will have limitations but I am not expecting to make something that will handle like a sports car. I want a cruiser that I can have fun with the odd time. The reason i want to do the mods is the satisfy my hunger for a challenging project. A simple engine swap wouldn't be taxing enough. I put 450hp into a 50 year old Mustang after upgrading all components with a good deal of custom work to make brake servos work with steering rack and exhaust manifolds, etc so the thought of some mods does not put me off. Another reason i would like to achieve 500hp+ is for nothing more than a bit of fun. I know some of guys are going to be thinking just buy an E55k/CL55k and drive the thing but my new project needs to built on a chassis 30 years old to avoid €2k in road tax which i wouldn't mind for a daily driver but not for a weekend toy.

Why tinker round with a M119 or M117 to get more power when the M113 5.5 already has 350bhp out of the box? In today's age, I would ditch the 25yr old CIS-E/distributor cap/rotor arm crap and go full standalone - far more tuneable and gives you the perfect foundation of further tuning down the line. Plus, the OP mentioned something modern, not period correctness.

Is there much difference in terms of the M113 and the M113K. The M113k should give me around 500hp out of the box?

let's do some comparisons...

Your going to need £2k+ worth of standalone ecu to get the m113 to run in the sec, your also going to need a transmission controller to run the gearbox, custom propshaft, custom throttle pedal. Then of course £1k+ for buying the m113 and box. So that's £4k gone to get the standard 350hp m113 running.

Whereas you can get a m119.960 for £500, which will work with the original gearbox and mounts, and can be made to run on the 560 management if desired for 325hp. That is a £3.5k saving!

Or throw a £1k standalone ecu on the later m119 to get 350ish hp, that's still 2.5k cheaper than the m113.

Your saying the cis-e and distributor controled ignition are crap, but the m119 didn't gain any hp when it changed to efi and coil on plug technology. So it obviously wasn't holding that engine back.

I can tell you that with the m119, 500hp can be done inside 10k. However I cant see the same happening with the m113.

As for the modern engine comment, the m113 has been around since 1999 so is hardly a modern engine.

You mention about £4.5k to get the M113 running in a SEC for 350bhp but as above would the M113k be a lot different?

I have a rough figure of around £20k-£25k for this project. I am not that worried about resale value or keeping the car period correct.

Using my very complex man maths calculator of only really counting bills above £1k as real money I do not think I am that far off even if i go down the route of an M113/M275

Car purchase - £5k
Engine/Drivetrain- £10-£12k
Suspension/Brakes - £5k
Wide Body conversion and full Repray - £4k

The majority of the work will be carried out by myself except where it is beyond my skills and the equipment in the garage. So bodywork/paint/structural welding and engine tuning/dyno work will all be done by others.

The question is, would you want to drive a 500hp sec without doing something about the brakes and suspension? I would say your looking at 5k to make it handle and stop well enough to use that kind of power.

The m113 with all the parts you need to make 500hp fitted in a sec, is going to cost alot more than 10k. Infact Niks guess of 15k is cutting it fine.

If I was going to spend that sort of money, I think I'd fit an m275 v12 from a cl600 bi turbo for a standard 500+hp without mods. You can always fit larger turbo's and intercoolers if you want more power.

I am prepared to spend a chunk of money on suspension and brakes. The M275 sounds interesting. There is one online for £3k with only 28k on it.

Can anyone confirm if there is any difference in the M119,M275 and M113 in RHD and LHD drive cars. i.e if i buy an engine from a LHD car will it work in a RHD without modification. The old yank V8 was the same except some mods to the exhaust headers.

 

[Red C220]

I hear what you are saying here. I realise the chassis will have limitations but I am not expecting to make something that will handle like a sports car. I want a cruiser that I can have fun with the odd time. The reason i want to do the mods is the satisfy my hunger for a challenging project. A simple engine swap wouldn't be taxing enough. I put 450hp into a 50 year old Mustang after upgrading all components with a good deal of custom work to make brake servos work with steering rack and exhaust manifolds, etc so the thought of some mods does not put me off. Another reason i would like to achieve 500hp+ is for nothing more than a bit of fun. I know some of guys are going to be thinking just buy an E55k/CL55k and drive the thing but my new project needs to built on a chassis 30 years old to avoid €2k in road tax which i wouldn't mind for a daily driver but not for a weekend toy.

I'll expand a little.

It's not just handling, you'll need major structural modifications to handle that power, basically a full roll cage.

The SEC is a pillarless coupe and the standard 560 motor twists the bodyshell as it is. A 500 hp SEC is going to be a bare shell build, effectively a road going racing car.

The lack of B posts on the shell design really does create a structural issue.

 

[John Jones Jr]

Using my very complex man maths calculator....

Oh, this is going to be good...

 

[GT500E]

I'll expand a little.

It's not just handling, you'll need major structural modifications to handle that power, basically a full roll cage.

The SEC is a pillarless coupe and the standard 560 motor twists the bodyshell as it is. A 500 hp SEC is going to be a bare shell build, effectively a road going racing car.

The lack of B posts on the shell design really does create a structural issue.

Interior out and adding a roll cage is still not enough to scare me off. I added a 4 point cage and chassis strengthening on my last build. Am i correct in saying the W124 is a unibody design also? Is there any other way to reinforce the chassis. i had a range of options on the mustang from frame rail connectors, Full frame rail X brace, welded in strengthening plates and obviously a roll bar.

 

[mazza]

I'll expand a little.

It's not just handling, you'll need major structural modifications to handle that power, basically a full roll cage.

T

I agree, 500 (charged horses is a bit too much) for the standard W126 Chassis

but you dont need a full roll cage

the SEC chassis can handle 400 bhp (Koenig specials) back in the day

SEC oem suspension is set for comfortable long cruises, back in the day the SEC was a cross continent mile muncher and probably still is.

the v12 conversion with over 400lbs of torque at your disposal from low revs, sounds very appealing

in any case, you will need stiffer springs, better shocks and address anti roll bars

mazza

 

[Niks]

GT500E - Since you own an a Shelby - you certainly aren't short of a few pennies. If resale value doesn't bother you and the car will be a keeper, to be honest I would actually make something out of it that no one else has, especially if you have 20-25k as a budget.

I personally wouldn't bother with an MB engine, and would seek an LS3 or 454 big block mated to a Tremec and MSD ignition. The tuning possibilities on those engines are endless. If your a purist and want to impress the MB community - by all means you can chose a M119, M117, M113 or a M257 as others have suggested. If this doesn't bother you, well you have many options outside of the MB box.

Whatever route you chose, I wish you success with it and if there is anything I can help with, let me know by dropping me a PM.

 

[carat 3.6]

You mention about £4.5k to get the M113 running in a SEC for 350bhp but as above would the M113k be a lot different?


Can anyone confirm if there is any difference in the M119,M275 and M113 in RHD and LHD drive cars. i.e if i buy an engine from a LHD car will it work in a RHD without modification. The old yank V8 was the same except some mods to the exhaust headers.

The m113k use's a liquid to air chargecooler, so your going to need to build a system for that. You'll want an extra radiator for it, an electric water pump to circulate the coolant, and of course a header tank.

There is nothing extra ecu or electrically speaking you'll need between the m113 and m113k.

There is no difference between rhd and lhd m119's and m113's, I'm 99% the same applies to the m275.

 

[V12]

Gotta be a V12, preferably M275 to be a bit more unique.

The W124 cabrio had extra chassis reinforcement. I've heard of the same strengthening bars being used on track day 190s and 124s.

I'm sure adding a bit of rigidity to the chassis on a 126 won't be the deal breaker for you.

 

[carat 3.6]

Gotta be a V12, preferably M275 to be a bit more unique.

The W124 cabrio had extra chassis reinforcement. I've heard of the same strengthening bars being used on track day 190s and 124s.

I'm sure adding a bit of rigidity to the chassis on a 126 won't be the deal breaker for you.

I think it would be the first m275 in an sec?

 

[jaymanek]

Have to add that a 560 engine is really a good mate to the W126...

If you really do need more power then has to be an early (1990/1991) M119 with the older style fuel injection system.

A crate LS engine sounds like fun and something really custom.

The most difficult part of this is the real metal widebody conversion... I have never seen a metal set of flares anywhere (apart from the ones on mine).

 

[Red C220]

If you really do need more power then has to be an early (1990/1991) M119 with the older style fuel injection system.

That's what I'm interested in your Blue SEC for Jay, when you're ready to let it go.

I'd like to fit an early M119 and gearbox from an SL500 with standalone ECU and modern fuel injection. The aim to run it at 360-380hp without the need to increase capacity.

I think it's a mod that would suit the car very nicely.