If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.
Here is a synopsis of the changes made by Ford for the Model year 1989 to make the standard 3.8L Engine into the SC version we all love (and hate at times).
To allow for the additional power generated by the engine there were new designs for reinforcement made on the following components:
Block
Main bearings
Crankshaft Bearing Caps
Crankshaft (Dura-cast initially and forged steel for the majority of the production run)
Steel crankshaft sprocket
Timing Chain
Cylinder head
Head bolts
Rocker arms
The throttle body was designed new for the SC motor.
Water routings in the engine were redesigned for the SC motor.
Intake Manifold:
Of course to accommodate the supercharger the intake manifold was changed to provide a way to mount all the upper engine components such as the SC, air bypass valve, inlet plenum etc.
Exhaust Manifold:
These to were redesigned for the SC version. Each side houses a Heated Exhaust Gas Oxygen sensor (HEGO). The use of the HEGO allows accurate sensing of O2 level in a lower temperature exhaust gas (200C- 392F) when compared to a EGO (unheated) sensor. On the SC the HEGO sensor on the right side is located in the exhaust pipe just downstream from the exhaust manifold for that side. On the left side the HEGO is located in the exhaust manifold itself.
Cylinder Block:
The cylinder block was redesigned and reinforcement was added to increase durability and strength of the block. The water passage opening locations were also moved.
Both the ATX and MTX camshafts (Automatic transmission equipped cars and Manual transmission equipped cars) were redesigned to allow for newly designed roller tappets. Roller tappets have the advantage of reducing sliding friction and improving fuel economy. Because of the choice made to include the roller tappets it was necessary to include guide plates and retainers to secure them.
The main bearing caps were made one inch taller and the cap bolts were increased in length to allow the caps to be secured properly to the block.
Initially Ford planed to use an improved method of manufacturing the crankshaft to add strength to the unit. It was referred to as Dura-cast. Due to production issues with the Dura-cast process, the vast majority of SC cranks were forged steel. Note that if you rebuild your SC Motor?the main journals can only be refinished to 00.25mm (0.010-inch) undersized and the rear main journal can not be refinished since it is already 0.010-inch undersized. The reason for the undersize rear journal was to prohibit any standard cast iron cranks being run down the line in an SC engine which would surely result in a warranty problem. If a standard crank would possibly be tried in a SC short block, the main bearing caps would not bolt down properly.
The balance shaft used on the standard 3.8 L (a feature used to reduce engine vibration) was eliminated and replaced by a spacer in place of the balance shaft drive gear.
A knock sensor was added to increase ignition performance. This is a piezoelectric accelerometer sensor that is designed to vibrate at the same frequency as the engine knock (pre-detonation). The sensor operates in consort with the EEC IV engine control system to retard ignition timing and hopefully eliminate the detonation before real engine damage occurs. If you ever have to replace one make sure you get the correct version since there are sensors made for at least 4 different frequency ranges depending on the application.
The rear main oil seal was modified to improve the sealing characteristics and to provide more durability. Some of you may have experienced rear oil seal failure in other Fords. Before approximately this vintage engine for Ford, the seals were mainly two piece and over time the rubber seal would actually wear a groove in the steel crank. The only true fix was to replace the crank. Now with this redesigned seal it is a one-piece unit which allows the use of a ?sealing ring? which can be installed over the groove and allow a new seal to be installed and the leakage to be stopped.
Cylinder Head:
The cylinder head was redesigned to increase the bolt boss diameter and deck thickness. The water passages (between the cylinder head and block( were revised to improve the sealing between the two components. The valve springs were improved by strengthening and made smaller in diameter. The spring seats were changed to accommodate the new spring design.
The cylinder head bolts are larger and have been made stronger.
Crankshaft Damper Assembly:
The crankshaft damper was changed to a cast aluminum piece to reduce weight.
The rear of the damper was fitted with a cutter for the Distributorless Ignition System (DIS) system. It has three vanes which when passing past the block mounted Profile Ignition Pick-up (PIP) sensor generates a signal to both the DIS Module (mounted on the top of the engine beside the Ignition coil pack) and the Electronic Engine Control Assembly (ECA {EEC IV Module}) and gives the base spark timing.
Camshaft:
There were two different types of camshafts designed. Automatic and manual transmission cars each had their own unique camshafts. They were color coded yellow for the ATX version and pink for the MTX version. The paint was applied to the rear end of the camshaft.
Timing Chain Tensioner:
A tensioner and corresponding snubber were added to the engine.
Pistons:
The piston domes for the pistons were redesigned to increase the performance. The pistons were also constructed of high silicone aluminum (hypereutictic). The compression ratio was 8.2:1.
Oil Pan:
The oil pan was diecast to reduce noise and vibration.
The oil level sensor was modified to also double for an oil temperature sensor.
Oil Cooler:
A Modine oil cooler was added to increase both engine and oil life.
Valve Covers:
The valve covers were diecast from magnesium for weight reduction.
Platinum tipped spark plugs were added for increased life and performance concerns of the engine.
Originally posted by 68GTO
I stand corrected. I was wrong.
:geeza: Member of WCR inc.Member of Crown Vic PI / Marauder Mafia
i think ill buy this as a backup. and 93 sc did you go to supercoupe school or something you seem to know these things inside and out. i think you gave me some info on the 5 speed transmission before. i have an 82 exp that i plan on tube framing and tubbing and was thinking the 92 sc 3.8 and 5 speed and harness that i have would make an interesting combo in a car like this. also is a 4.2 f150 motor the same engine family. would a 4.2 crank work as a stroker for a 3.8?
I've owned a few. They are the same family, and I'm pretty goddamn sure that the 4.2 crank will go into the 3.8 block. If I remember right that's what aloft of the 3.8 guys use as a stroker crank. I'll double check on that and drop you a PM.
Originally posted by 68GTO
I stand corrected. I was wrong.
:geeza: Member of WCR inc.Member of Crown Vic PI / Marauder Mafia
Correct, the 3.8L and 4.2L are the same block, different crank. The truck crank is often used as a 'stroker' for the cars (I'm acutally running a built short block out of a '97 F150). Alot of single port V6 mustangs use the SC set up, but only make minimal power unless upgrading the internals (roughly 200 hp/300tq).
~Matt
1998 Roush M112: Aluminum block 4.6 2V T56 1 of 1 made
1999 SVT: Daily driver, part time track car
1970 Mach 1: Resto-modded 351W
2000 Roush #5004: World's FIRST M112 supercharged V6 Mustang 1 fo 106 made SOLD, but not forgotten.
I called the guy friday said i'd take it, got there sunday there's a note on the door that says he sold it friday to some one else before he talked to me?
any ways is there anything else that would need to be done to a 4.2 crank to make it fit the 3.8 ?(milling oil slingers,rebalance .etc ) or is it a direct bolt in any tips on if anything needs to be notched for clearance or whatever?
and the big question .does anyone have a 4.2 crank available?
The 4.2L crank is cast, same as the mustang 3.8L crank. The Super Coupe had a forged 3.8L crank. We (sixers) have yet to have the crank be the week point.
Here's the info on swapping the 4.2L into the 3.8L Mustang:
Early 97-98 4.2s had a 2-pc main girdle that connected the 1st to the 2nd main cap and the 3rd to the 4th main cap and had larger main bolts. Mid-1998 and up 4.2s used a 1-pc girdle that only connected the rear 3 main caps and had smaller main bolts.
To use the early 4.2 in any Mustang will require replacing the girdle with a newer 3 main style from a 4.2, get a 99-up 3.8 girdle or just delete it. You will also have to cut the girdle studs sticking out of the head of the main bolts on the 1st main bearing. The 99-00 3.8s used a factory windage tray/girdle that is better than nothing but certainly not ideal. The 01-up 3.8s use the same windage tray/girdle as the 4.2.
Late 00 3.8s are actually early 01 spec engines that are internally balanced. If you have one of these.....just use the notes for an 01-up.
94-98 Single port heads
- 4.2 shortblock
- Single port heads/fuel rail/intake
- Mustang 3.8 water pump
- Auto trans = 4.2 or 01-up flexplate
- 5spd = 01-up or rebalanced 3.8 (0 or neutral) flywheel and a pilot bearing
- Re-use your stock cam position sensor
- 01-up 3.8 oil pan
- 01-up 3.8 oil pick-up tube and screen
- 4.2 damper or 01-up 3.8 damper (use the 01 pulley for blower cars)
- Re-use the stock 3.8 oil pressure sender and tube
- Re-use the Mustang headers
- You can use the 4.2 or 3.8 dipstick. Just keep track of where 5 qts puts the mark when refilling with oil.
94-98 Split port heads
*** You will need to perform all the mods required for a split port conversion plus these steps for the 4.2 (see pbmilan or V6sprout for the video) ***
- 4.2 shortblock or longblock
- You can use the 4.2 heads
- Mustang upper and lower intake
- Custom return style fuel rail (VMP has them)
- Mustang 3.8 water pump
- Auto trans = 4.2 or 01-up flexplate
- 5spd = 01-up or rebalanced 3.8 (0 or neutral) flywheel and a pilot bearing
- Re-use your stock cam position sensor
- 01-up 3.8 oil pan
- 01-up 3.8 oil pick-up tube and screen
- 4.2 damper or 01-up 3.8 damper (use the 01 pulley for blower cars)
- Re-use the stock 3.8 oil pressure sender and tube
- Re-use the Mustang headers
- You can use the 4.2 or 3.8 dipstick. Just keep track of where 5 qts puts the mark when refilling with oil.
99-00 split port heads
- 4.2 shortblock or longblock
- You can use the 4.2 heads
- Mustang upper and lower intake and fuel rail
- Mustang 3.8 water pump
- Auto trans = 4.2 or 01-up flexplate
- 5spd = 01-up or rebalanced 3.8 (0 or neutral) flywheel and a pilot bearing
- Re-use your stock cam position sensor
- 01-up 3.8 oil pan
- 01-up 3.8 oil pick-up tube and screen
- 4.2 damper or 01-up 3.8 damper (use the 01 pulley for blower cars)
- Re-use the stock 3.8 oil pressure sender and tube
- Re-use the Mustang headers
- You can use the 4.2 or 3.8 dipstick. Just keep track of where 5 qts puts the mark when refilling with oil.
01-up split port heads
- 4.2 shortblock or longblock
- You can use the 4.2 heads
- Mustang upper and lower intake and fuel rail
- Mustang 3.8 water pump
- Auto trans = your stock flexplate
- 5spd = your stock flywheel and a pilot bearing
- Re-use your stock cam position sensor
- Your 01-up 3.8 oil pan
- Your 01-up 3.8 oil pick-up tube and screen
- Your stcok 01-up 3.8 damper
- Re-use the stock 3.8 oil pressure sender and tube
- Re-use the Mustang headers
~Matt
1998 Roush M112: Aluminum block 4.6 2V T56 1 of 1 made
1999 SVT: Daily driver, part time track car
1970 Mach 1: Resto-modded 351W
2000 Roush #5004: World's FIRST M112 supercharged V6 Mustang 1 fo 106 made SOLD, but not forgotten.
Comment