M5 & M6 Engines - S38/S88

M5 & M6 ’85-’93 - 6 Cyl DOHC Engines
Engine SeriesHorsepowerPriceCore Deposit
3700 Sport Engine310 HP$11,495Own Core
3700 Rally Engine350 HP$12,995Own Core
3600 Forced Induction Engine12 lbs 550 HP$13,995Own Core

Price Page Booklet

3700 Sport Engine  A factory S38 or S88 engine has a life expectancy of about 175,000-185,000 miles before they go into high oil consumption due to blow-by.This engine offer the M Power owner a decent performance increase, extended Engine life, no lose in fuel economy, at a reasonable price. It’s a great upgrade over a stock M engine. The following is a list of mechanical changes made to this engine;

  1. Increased displacement for more torque by 86 mm forged Chrome Moly steel crankshaft.
    1. 95 mm forged alusil 11.5:1CR pistons with vented skirts.
    2. Increased head flow with 29.5mm intake ports with surface turbulence valves to reduce detonation and increase fuel economy.
  2. Manganese bronze valve guides.
  3. Improved outer valve springs.
  4. New S50 chain tensioner, upper and lower tensioner rails, and plastic guide rail.
  5. New timing and oil pump chains.
  6. MM blueprinted oil pump.
  7. Options commonly purchased with this engine:
    1. B36/38 intake cam.
    2. Ported intake manifold (customer’s manifold).
    3. 240mm light weight flywheel and clutch assembly.
    4. MM EPROM chip.

MM 3700 Rally Engine   Currently, this is the most popular S38 M engine we build. The last 3700 Rally we pulled off the dyno made 373 HP and 318 Ft/Lbs of torque (flywheel). It made within 85% of its full torque from 3500rpm to 7700rpm. That a torque curve about as flat as Kansas! We build a lot of these engines for M5 /M6 owners and they really transform these cars into hot performers. Here is a list of the changes made to the 3700 Rally.

  1. Increased displacement for more torque by;
    1. 86 mm forged Chrome Moly steel crankshaft.
    2. 95 mm forged alusil 11.5:1 CR pistons with vented skirts.
  2. Increased head flo with 31 mm intake ports with surface turbulence valves to reduce detonation and increase fuel economy.
  3. Manganese bronze valve guides.
  4. Improved outer valve springs.
  5. Hotter Rally intake cam.
  6. Premium light weight 4340 Chrome Moly forged “H” beam rods.
  7. S50 chain tensioner, upper and lower tensioner rails, and plastic guide rail.
  8. New timing and oil pump chains.
  9. MM blueprinted oil pump.
  10. Options commonly purchased with this engine:
    1. Ported intake manifold (customer’s manifold).
    2. 240mm light weight flywheel and high torque clutch assembly.
    3. MM EPROM chip.

3600 Force Induction Engine   Specifically designed for boost. The internals of this engine (pistons, pins, rods, and rod bearings) are all engineered much stronger to take higher cylinder pressures. If you are a “boost junkie” who likes scary fast this is your fix!

  1. 86mm forged Chrome Moly steel crankshaft for more torque.
  2. Stronger 144.75mm “H” Beam rods have 4 oil squirter grooves located at the big end to cool off the piston and lubricate the piston skirt.
  3. Special coated tri-metal rod bearings.
  4. Special 94mm Forced Induction Forged Pistons.Increased head flow with 31 mm intake ports with surface turbulence valves to reduce detonation and increase fuel economy.
    1. Lower 8.6:1 CR with a slightly “dished design” for boosting
    2. No valve pockets to burn away.
    3. Piston Crown is 2mm thicker and it has a ceramic thermal barrier allowing it to take temperatures up to 1350 ° F continuously without failure.
    4. High Silicon Content Alloy (13%) for tighter cylinder wall clearance, greater ring and groove life, & to minimize skirt scuffing.
    5. Piston slit just under the oil ring to lower piston expansion.
    6. Lower placement of the top ring groove to protect the ring from combustion.
    7. 4mm Oil Ring for excellent oil control.
    8. Option: for higher boost levels (16 lbs. or more) we use hard anodized pistons
  5. Increased head flow with 31mm intake ports with Surface Turbulence valves to reduce detonation and increase fuel economy.
  6. Manganese bronze valve guides.
  7. Improved outer valve springs.
  8. S50 chain tensioner, upper and lower tensioner rails, and plastic guide rail.
  9. New timing and oil pump chains.
  10. MM Blue Printed Oil Pump – delivers 20% more flow.
  11. Options: commonly purchased with this engine:
    1. Ported intake manifold (customer’s manifold).
    2. 240mm Lightened Flywheel and HiTorque Clutch Assembly

The following upgrades are also included:

  1. MM Blue Printed Oil Pump – delivers 20% more flow.
  2. Stronger 144.75mm “H” Beam rods have 4 oil squirter grooves located at the big end to cool off the piston and lubricate the piston skirt.
  3. Special coated tri-metal rod bearings.
  4. Special 94mm Forced Induction Forged Pistons.
    1. Lower 8.6:1 CR with a slightly “dished design” for boosting
    2. No valve pockets to burn away.
    3. Piston Crown is 2mm thicker and it has a ceramic thermal barrier allowing it to take temperatures up to 1350 ° F continuously without failure.
    4. High Silicon Content Alloy (13%) for tighter cylinder wall clearance, greater ring and groove life, & to minimize skirt scuffing.
    5. Piston slit just under the oil ring to lower piston expansion.
    6. Lower placement of the top ring groove to protect the ring from combustion.
    7. 4mm Oil Ring for excellent oil control.
    8. Option: for higher boost levels (16 lbs. or more) we use hard anodized pistons