Diff B/T the motor fr M1 & 88 M6? I want 470 HP !

[M6SCOTT]

What are the major differences between the motor in an M1 which produces 470 hp in racing form, or so the article I read said, and my motor. Asked this before. What is the most HP and torque I can achieve NA?

[tschultz]

For the group 5 series, Jochen Neerpasch wanted a mid engined racing car. The development of the E26 ///M1 started in 1976. The idea was to develop a racecar first and a road car second. Since BMW did not have the capacity or the expertise to build a tube framed car, BMW Motorsport contacted Lamborghini to help with the development and the production of the chassis. But Lamborghini came into financial troubles and was not able to fulfill its commitments to BMW. This delayed the production of the E26 ///M1 with more than a year and by the time the production of the ///M1 started, the rules for the group 5 touring car championship where changed and ruled out mid engined sports cars. At that time, Jochen Neerpasch had his new racecar, but could not use it. Max Mosley of the FIA came up with a brilliant idea. A new race class was established specially for the ///M1. This new race class, the Group 4 Pro Car series was scheduled to take place before a Formula 1 race with a few formula 1 drivers and privateers.

The engine for the ///M1 was an evolution of the M49 engine of which the development stopped in 1977. However the new M88 had significant changes to allow it to be used as a production engine for road cars. The same changes were made when building the E26 ///M1 for sale as a road car, a requirement for the group 4 regulations. The Group 4 rules required that 400 units of that same car would be made within one year. The direct drive of the camshafts by a gear train was abandoned for a direct chain drive to reduce the interior noise. Like the M49, the M88 engine also used a Kugelfisher mechanical fuel injection system. The cylinder head of the M88 consisted of two pieces. The lower piece contained the intake and exhaust ports, the valves and the spark plugs. The upper piece contains the buckets, shims, camshafts and bearings
Compared to the M49/3, the M88 had a slightly smaller displacement (3453cc). This was achieved by reducing the bore slightly to 93.4mm. However the stroke of the engine remained the same (84,0mm). To test if the M88 engine would be reliable for a production engine, BMW placed the existing SOHC drive train on the M88 cylinder block. This engine, called M90 used a regular Bosch L-Jetronic (predecessor of the Motronic) fuel injection system and yielded 218hp.

The road going ///M1 used the M88 engine. The M88 yields 277hp @ 6500RPM and 330nm @ 5500RPM. This was more then enough to propel the 1418kg sports car in a little more than 20sec to the 200km/h mark.

Since the E26 ///M1 was designed for racing first, the M88 engine was heavily modified. For road use, the M88 is tuned to offer a good compromise between tractability, engine longevity and performance. Engine longevity is not that important for racing and for group 4 and 5 Procar races a lot more than 277hp was required. New camshafts, larger valves, reshaped ports, throttle slides instead of butterflies, forged pistons and a completely different exhaust system helped to increase the power to almost 500bhp. For Group 5 purposes, two turbo chargers where added. This version is known as the M88/2. Depending on the boost pressure, the power output was between 850bhp and 950bhp.

Despite that BMW already switched to a new engine codex in 1983, the new 24-valve engine kept the family code M88. It was not before 1986 when the S38 designation was used for the catalyst version of the M88/3. The S38 stands for, 'S' means that the engine is originated by BMW Motorsport, the '3' means that it is derived from the M30 engine family and last but not least, the '8' is chosen to make a reference to the legendary M88.

To meet US exhaust emission regulations of that time, the catalyst equipped S38B35 replaced the M88/3. The S38B35 kept the M88/3s bore, stroke and cylinder head, but to install a catalytic converter, the compression ratio decreased from 10.5:1 to 9.8:1. The equally tuned exhaust headers of the M88/3 where replaced by log headers. Al these changes decreased the engine performance. The S38B35 delivered 260hp and a torque of 330nm (243lb/ft) at 4500RPM. The US E28 ///M5 and E24 ///M6 also had more options fitted, many of which in Europe could only be bought by special order. As a result, the US cars where noticeable heavier than the European cars and this had an impact to the cars performance. The European E28 ///M5 can do the 0-100km/h (0-62mp/h) sprint in just 6.5sec, while the US version needs 0.3sec more.

There are large differences: wet sump vs dry sump, l-jetronic vs motronic fuel injection, cat vs no cat.
I think what they share sort of stops at the block and crank.

Technical specs:







More about the history of the engine and how it impacted many generations of BMW's:

http://drive4corners.com/beginning-l...tor-evolution/

[M6SCOTT]

Who could build me this engine at 470 HP for my M6 ? Would the frame handle the power ?

[tschultz]

Your best bet is Paul Burke, but beware it will cost $$$$.

I refer to my friend Ken H who I saw recently and his car Lucifer's Hammer: http://www.mye28.com/viewtopic.php?t=26880

[Shipper]

You can get 490hp from a turbo M30 at 30% of the cost. Or, turbo your M88 for 500hp with little work needed. The problem with 490hp in an NA M88/3 is that, unless you take it out to 4 litres (think $4k for the new crank alone) it will be spinning up well past 8500rpm to get there and, would be a fragile engine needing a refresh once a year if driven hard. Anyone can get hp. It's really torque multiplied by revolutions.

There is an endurance racer in Norway running 360hp (S38B38) and it runs 0-62 in 4.5s and onto 305kmh. You would be better off going for a complete package. Build the M88 to 370hp, get the right diff ratio and right gearbox and you'll mirror the above. A 490hp M88 would be track only idling at 1500rpm and as rough as guts down low.

[TJC1]

You can get 490hp from a turbo M30 at 30% of the cost. Or, turbo your M88 for 500hp with little work needed. The problem with 490hp in an NA M88/3 is that, unless you take it out to 4 litres (think $4k for the new crank alone) it will be spinning up well past 8500rpm to get there and, would be a fragile engine needing a refresh once a year if driven hard. Anyone can get hp. It's really torque multiplied by revolutions.

There is an endurance racer in Norway running 360hp (S38B38) and it runs 0-62 in 4.5s and onto 305kmh. You would be better off going for a complete package. Build the M88 to 370hp, get the right diff ratio and right gearbox and you'll mirror the above. A 490hp M88 would be track only idling at 1500rpm and as rough as guts down low.

Sage advice, Shipper. It should also be noted that 400 to 500 horsepower in today's cars is not the same as getting that same number out of old tech like the M88/S38 because the new engines and the systems designed for them are simply that "Designed" with that much horsepower in the first place and not "Modified".

[GazM3]

To build a high hp m88/s38 is not that difficult. Bring te engine to Melbourne and get Matt you build it. I'm having 450-470 bhp done in a street driven engine. U don't need 4ltr crank tye m30b35 86mm crank will be fine. The difference between building a 400 bhp and a 450+ is only bigger lift cams higher compression and larger valves. You would need to rev to high 7's. What was thought impossible 10yr ago is now totally plausible. U can tame a grumpy camshaft somewhat with sequential injection and individual coils. I'm sure u coils go well into the 500bhp zone if using e85 fuel and 14:1 compression but as shipper 01 stated you would need to rev it up pretty hard which would need periodic engine refreshing

as as for the diff the large case std diff is pretty strong. So is the gearbox the only real issue is ripping te subframe away from the body Sheetmetal.

[Shipper]

e85 fuel, 14:1 compression, bigger valves. Yep Gaz, it can be done but $$$$ and you would be driving constantly between 5500rpm and 8500rpm to keep the car on the boil. I'm sure Matt can do it. I have absolutely no doubt Matt can do it. But unless it is a track only car I'd go turbo.

Edit: Here's the link I mentioned earlier to the M5 racer e34 with the S38B38 in stock format. http://www.vds-racing.com/cars_fr.htm

So; 345hp, 410nm of torque (stock),1450kg (close to a 6'er and easy to get a 6'er to this), 285mm rear tyres obviously for grip and quick acceleration. 4.5s 0-62 and 302km max vel.

Given this, either turbo what you have or take it to 350hp to 390hp as an NA engine, put bigger tyres on the rear, increase displacement to 3.8 litres plus (for torque from an NA engine. Torque generally equals displacement multiplied by 107. i.e. 3.8x107 = 410nm), and you should be able to mirror the above all without an engine that is as fragile as eggshells.

If I were you, I'd get Todd to design a 400hp turbo kit for me with no internal changes. Will (Todd can confirm here) get you 400hp plus and 500nm plus. A rocket, on low boost and not too stressed.

[e24mpwr]

Frank Fahey can build you a motor too (also big $$$)

Not sure you'll like how "streetable" something like that is...

[brickwhite]

It would probably be cheaper to put a GM LS3 or LS7 to get that kind of HP out of your e24

M88/S38 are not cheap to add power or just keep running.

Just like Frank did.

http://www.frankfaheymotorsports.com.../flash/M6.html

[GazM3]

e85 fuel, 14:1 compression, bigger valves. Yep Gaz, it can be done but $$$$ and you would be driving constantly between 5500rpm and 8500rpm to keep the car on the boil. I'm sure Matt can do it. I have absolutely no doubt Matt can do it. But unless it is a track only car I'd go turbo.

d.

No disagree. The high compression smooths out the effect of the big cam. You would have idle around 1000 and good drivability from 2500rpm.

I cant work out what all the fuss is about building a worked over s38/m88. They are basically an m30 engine with 4 valves. They were designed as a 470bhp race engine initially designed to rev to mid 9's and would make that power on products available in the late 70's.

I cant also see why the costs are so high to upgrade it. The only real big $$ items are the timing chain/guides (which u have to replace in most cases with std spec), engine management system, and if u want more capacity the longer stroke cranks can be pretty pricey. In most cases with the s38b35 u have to upgrade cams so costs are similar if going 1 size up on std or 3 sizes up. Although you don't have to change pistons to rebuild it's often a good idea to use more compression and having them with the valve recesses allows to optimise the cam timing to get te best power and driviabllity out of the engine.

So going from a totally stock rebuild with pistons, u are only say 2.5k more for cams and probably about 3k more for a good engine management system up and running. So the difference from a 300bhp rebuild to a 400bhp one should be about 5-6k. Going to 450bhp prob have to spend another 3k to upgrade the valve size and some head porting. If match the ports on the s38b38 head they flow an amazing 309cfm at 12.7mm lift which equates to 480bhp of flow.

[Shipper]

Gaz,

Add up all of those costs. By time you include braided lines, 2 performance cams, high compression pistons, crank balancing, flywheel lightening and balancing, head porting, bigger valves, gaskets, engine management................ you are looking at $20k plus. You and I are blessed with Matt and decent mechanic rates. I believe that to do it right, excluding your mechanics labour rates, $20k in parts and equipment then add labour.

An LS3 is cheaper and can come with a 6 speed gearbox. I would simply not do a non BMW transplant and had the opportunity. I went the S38B38 route but, all up, noting that the engine came with $5k of head work and completely rebuilt with zero miles, by time it's all finished, I'm still up for $20k!

[1SIKSIX]

Why not turbo the m motor and make 600 at the wheels? Me thinks this can be done for 10k and a stock block.

[GazM3]

Hey josh, it's only money.


The ls3 no doubt has the power but is not a very exciting engine to use in anger. I have one and it's my least favorate car to drive even though it has around 450hp. The engine is too linear and feels the same whether u rev it to 3000 or 6500. As a transplant I'd much prefer the m60b40 even though it makes 150bhp less. It's a much more enjoyable engine to use in anger.

[tschultz]

Why not turbo the m motor and make 600 at the wheels? Me thinks this can be done for 10k and a stock block.

Unfortunately not reliably.

[M6SCOTT]

Does anyone have the number for Paul Burke ? I have tried several times to call the number I found on another forum but no answer or return call.

- - - Updated - - -

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[Mike WW]

Does anyone have the number for Paul Burke ? I have tried several times to call the number I found on another forum but no answer or return call.

- - - Updated - - -

?

I think he had some health issues but is doing ok now. And he is noted for being difficult to reach, though I hear phone is best.

I remember back in the day Dinan built some S38s to around 400HP. I think they were even Calif legal. That was with deep pockets to engineer.

[youngbimmer]

Screw it and swap a S54 in there

I had no idea S38s could be built to get 470HP naturally aspirated. That is totally nuts. Probably would have to be flogging the motor very hard to get that kinda juice out of it.

[DaHose]

Take a listen to an M1 Procar on the track. They wind those suckers upwards of 8000.

Korman lists a stage II stroker build for the S38 at 365HP/322 tq. That would be a damned fine, streetable engine.

Jose

[youngbimmer]

Metricmechanic also sells a modified S38 motor that supposedly produced 370bhp for 13K: http://www.metricmechanic.com/product-prices/engines/m5-m6-s38-s88/

or a kit if you want to do it yourself and save some money: http://www.metricmechanic.com/produc...ly-engine-kit/

[FlyOverCountry]

Engine Series
Price
Core Deposit

3700 Sport Engine - 310 HP
$10,995
Your Core

3700 Rally Engine - 370 HP
$12,495
Your Core

3600 Turbo Engine - 390 to 550 HP
$12,995


WoW!

[GazM3]

The metric mechanic seem to do a good base kit and make good power 370bhp in a fairly conservative state of tune using just a chip with the std air flap. They use the m30 86mm stroke crank. Their upgraded intake cam seems to be a regrind so it would only have standard valve lift. Their "kit" with adjustable slotted cam wheels, bigger cams, and a standalone ecu would easily make 420+bhp. The engine would spin to 8k and it would last easy 60-100000miles as long as u kept up the oil changes and maintainance.

The m88 used to rev to mid 9's back in the day. Also in the late 70's pistons were heavy and wouldn't tolerate te speeds they do now. I'm sure if you built a big compression 550bhp m88 spinning it to over 9k regularly I rekon u would still get reasonable engine life but u would need to periodically refresh it perhaps at 10-15000miles or so. I guess here we ain't talking those sort of power levels.

[Shipper]

So Gaz, should I get Matt to build me a 550hp S38B38 race engine for my E3 racer?????

[GazM3]

Why not. If u have the funds to build it then do it.
The e3 chassis may grumble a little.

He was 1/2 way through building a 14:1 comp s38b38 but the client has either run out of funds or hot sidetracked as it's been dormant for over 12months.

[Shipper]

Hmmmmmmmm. A half built 14:1 comp S38B38. Interesting.