3.8L TO 4.2L SWAP

[Lazerred6]

Does anyone know what goes into it

I have a 1998 sixer and as you all know it lacks when it comes to power. the 4.2 from the f150 makes more power and from what I have heard is very similar to the 3.8. I don't want to swap to the V8 because there is way to much involed in that swap I'm looking at this one due to the possibility that most of what I have may (I don't know) swap over without to much trouble.

If anyone has specifics or can point me to a thread that explains it I would be greatful.

[Steeda21]

i totally know what you mean i want to do a v8 swap but it would be way too much money and it would be very difficult with all the wiring and such. Im assuming it would be a straight swap with minor adjustments like the 4.6 swap to 5.4.

[Lazerred6]

Thats what i'm hopeing

Does anyone know of a thread that explains how to do it or has a parts list?

I mean seriously what v6 owner wouldn't want this if it easy to do and not crazy expensive
the specs on my car stock are 150 hp 200ish ft/lb TQ
and the 4.2 is 1997-2003 - 4.2 L Essex v6 , 202 hp 252 ft/lb TQ

Obviously there is a clear winner.

[Dream]

i was talkin about this with a friend last summer. he says "fuckin do it. i guarentee you wont regret it". i been bustin my ass to find an engine thats in my price range but not so cranked on miles. we started to mess around and he says it you want the best 6er around get a supra engine in there. well....im more of an american lovin person and ide rather crank up on a big engine. makes more sence.

i really hope you do it. all you need accordin to him is basics, just pumps and injectors and stuf like that. the stock plumbing SHOULD hold up he said, but no guarentees far as i know.

[Lazerred6]

Found it!
on another site


I have seen many questions...but few facts. This is what you need. I converted my 99 4 years ago.


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, 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.

Edit by 97Stallion: here's some extra info. 97-98 4.2L engine are directly compatible with 94-98 3.8 crank pulleys. So if you have a 97-98 4.2 crank and balancer, you can use your 3.8 crank pulley/underdrive pulley.


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
- V6 Mustang bellhousing
- 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
- V6 Mustang bellhousing
- 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
- V6 Mustang bellhousing
- 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
- V6 Mustang bellhousing
- 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 stock 01-up 3.8 damper
- 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.