4.2L Stroker Build


Well it's been a little while but I got my engine back from the machine shop a few days ago and I'm about to start assembly. I will be posting an update of everything that was done, and the price, of the machine shop work in the next day or so.

I decided not to have the machine shop assemble my engine, I wanted to do it myself. This could prove to be a bad decision, but the whole reason I'm doing this is to have fun. Once I source a few missing parts I will start posting updates of the assembly process.

Does anyone know where I can source the following parts:
  • Alignment dowels - I can't see to find replacements. The ones for the timing cover are in good enough shape to reuse. but the cylinder head dowels are pretty mangled from when they got removed. Can't seem to find them anywhere, and I'm trying to avoid buying more parts from Ford, they are starting to hurt my wallet. (I will go to Ford if no other options present themselves.)
  • Crankshaft end bolt - the one that holds the harmonic balancer on. Mine has disappeared.

Also as a very delayed response to the head porting, I'm running stock heads for now. I want to see what power I'm able to make before messing with the heads.

Another decision I've made, I'm tuning the car myself. (this will probably result in me blowing something up). I'm a computer person, went to college for it ect. so I decided to spend the few hundred buck on the stuff to tune my engine myself. I have all of the hardware, software, licenses to do it now. I will be making a big post on all of that when the time comes. As well as pricing as always.

Well if anyone has any questions let me know, in the meantime I'm just going to keep trudging along with this project.



All machine shop work was done by TEM Performance in Napa California. I highly suggest anyone in the area use them if possible. Rich (the owner) is awesome, and worked with me to fix some of the issue I hadn't thought of.

This is the first time I've done this much to an engine, so if you see something that might be wrong, or out of place, please say something. Better safe than sorry.

The crankshaft I originally bought turned out to be trash. The mains had a taper of about 0.0007", which is no good, decided to get another crank.

Measurements from the shop:
1: 2.5098 on the front of journal 2.5105 on rear of journal .0007 taper
2: 2.5091 on the front of journal 2.5100 on rear .0009 taper
3: 2.5093 on the front of journal 2.510 on rear .0007 taper
4: 2.5097 on the front of journal 2.5104 on rear .0007 taper
allowed taper = .000000000000000000000000000000000000

Connecting rod big ends were ovaled a bit, the shop was able to find some bearings with a 0.002" oversized OD. so the big ends of the con rods were enlarged by 0.002"

The valve springs I originally purchased (based off of information found in multiple places online) were WAY too strong for my heads (without a lot of work to strengthen them). they measured at 208lb of seat pressure (I think that right, I have the numbers in front of me but I'm not super knowledgeable about valve spring rates and stuff). The machine shop ended up finding a different set of springs that worked with a 0.015" valve shim, and different style valve stem seal ( I will get with the shop again to get exact details on this incase anyone wants the info.)

Valve spring info from invoice:
Valve Springs, Single, Beehive, 1.061 in. Outside Diameter, .952 in
.015 valve shim .765 x 1.00

Other work done:

  • Valve job
  • Clean and Magnaflux block
  • Bore and Hone
  • Balance crank
  • Remove and replaced pistons on rods
  • Remove and replace cam bearings
  • Other misc stuff that was included in other services (removal of freeze plugs and stuff like that)
All in all the machine shop cost me $2676.58 after buying a new crank and bearings and all that jazz.

Right now I'm waiting on a few parts:
push rods (getting them from Rock Auto)
Freeze Plugs (getting them from Rock Auto)
Main cap bolts from Ford (should arrive at ford Tuesday)

Not Ordered Yet:
Head alignment dowel pins
Main crankshaft end bolt (for harmonic balancer)
Bolts for flex plate
Woodruff key for crank

I'll likely get most of those parts from Ford, if not I'll go pull some from an F150 and Mustang at the junk yard.

Well I think that about covers it for now. Any questions let me know.

Side note: the container on top of the car is sitting on a sun roof, it's not hurting the paint.

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Quick Update

Found some problems, solved some problems, ordered some parts.

Found that one of my rod bearings was bad, had a dent of sorts in the back.

Solved this by ordering a new bearing, easy, just annoying. Waiting on this part to continue right now.

Another problem I found was that my Camshaft spacer had a chunk missing out of it. This was caused by me hitting it with a hammer while trying to remove the woodruff key from my original cam. Just waiting on ford to get the part in.

New parts acquired:
Cylinder Head Alignment Dowels
Timing Cover Alignment Dowels
Crankshaft End Bolt and Washer (the washer costs more than the bolt...)

Once that rod bearing comes in I'll be able to throw the heads on and do up the valvetrain. I'll likely update again once that is complete.

James Carr

sleep-er noun = fusing speed with secrecy
I've been away for a bit but back now watching this thread very closely I have all of this to do very soon....

6 Shooter

Well-Known Member
Sure hope the machinist balanced the crank against the weights of the rods, pistons, rings, wristpins, and clips. All pistons should weigh within one gram from the heaviest to the lightest. Rods should be weighed separately on both ends and end weights should be the same with all 6 rods. The crank should be balanced to the weights of the reciprocal and rotating parts mentioned to within 2-3 grams in total. The motor will then be super smooth. 2-3 grams is about the weight of 2 one dollar bills.


Quick update:

Yes when the Machinist balanced the crank against everything.

I got the engine together and installed in the car. and IT RUNS!!!

haven't tuned it yet. i was just pushing to get it in car before I had to have carpal tunnel release surgery.

In the next week or so I will be posting a big update on the install, and some picsl, as well as a video of the engine running.

One problem I've noticed:
Car runs nice and smooth (even without a tune), except for one thing. When I'm over say 1750 - 2000 rpm, then I let off the gas, I get a somewhat loud ticking sound. I'm thinking it might be a lifter, or rocker, not sure. It also only really happens under load. This will be the first thing I address when I'm able to get back to working on it.


Possible very big problem.

I changed oil today, engine has about 45-60 minutes of run time on it. There seemed to be a decent amount of bearing material in the filter. (non in the oil that came out of oil pan)

Only magnetic bits I found were very, very, small. I'm 95% sure they came from cutting the filter open with a dremel.

Here's a pic of the biggest flake I found. Pen used for size comparison.


So y'all think I should run the engine a bit more then check again, or go ahead and pull it back out and tear it back down? I really don't want to pull it, but it that's what has to happen...

James Carr

sleep-er noun = fusing speed with secrecy
don't use a dremel buy a filter cutter or make one AND more importantly have this next oil change sampled and sent off for oil analysis this will put you closer to the area that the metal particles are coming from


How long should I run the engine again before changing the oil?

I had another idea for this engine.
Is there any interest in a video series on removing and tearing down the 3.8 split port? I don't work a normal job so it would be doable.


Active Member
Does the engine still make a ticky ticky noise?

It's normal to see (some) metallic material in the first oil change after a rebuild. I forget the name of it and am too lazy to Google on my phone but all of the bearings have a top layer that comes off. Also, the oil passages dont always get 100% cleaned out at the machine shop and metallic dust often gets flushed out into the filter on first startup. The pics u posted look fairly normal to me.

How is the oil pressure cold and warm?


Active Member
The top layer of all bearings is called the babbitt. It's designed to be a self lubricant (more or less) and a cushion for the copper and steel layers when there is a lack of oil. It's not designed to come off under normal conditions but can come off if the engine wasnt primed before initial starting. Did you use a drill to prime the pump to get oil flowing up to the rockers before the initial fire up?


I did prime the engine, but stuff happened and i didn't start it until almost 24 hours after priming. Maybe that was the problem?

I do still have the ticking / knocking sound when decelerating after heavy load (also only happens when engine is fully warmed up). I'm thinking this is a timing issue, I have a new cam and stuff and still running stock tune. I'm still in the process of learning how to tune. haven't gotten to spark tables yet.

I don't have an oil pressure gauge hooked up to the engine (other than stock gauge). I did test the oil pressure with the engine on the stand and was getting like 82psi. I'll see if I can get a real number from my tuner, or obd2. The stock gauge sits right in the middle like normal.


Was able to get a short video of the sound it's been making. Usually only happens when decelerating, but I got it to happen while sitting in the garage.

It's a very short video, and you might need headphones to hear it.

The video may not be any help at all.


I'm stepping away from the Mustang for a week. I just need to take a break and come back at with with fresh eyes. I'll get a better video then.

Thanks for all of the help so far everyone!


Okie Dokie, I'm finally getting back into this.

There are 2 main problems I'm trying to figure out right now.
  1. Engine knocking / ticking sound.
    • While driving I only hear it while decelerating right after acceleration
    • In the video I made it happen while sitting in garage just playing with gas pedal. Seems to happen while engine is reving in video
    • went through engine with a stethoscope while idling, didn't hear anything obvious.
  2. Transmission fluid leak
    • Big enough that after 3 days of sitting no fluid registers on the dip stick.
    • after engine is warmed up I always have some amount of smoke coming from back of engine (by the smell it's obviously trans fluid)

Id be real happy if this knocking sound turns out to be a tuning problem since the engine still hasn't been tuned.

I'll be getting the car up on a lift or jack stands this weekend to address the trans fluid leak.

Well there's not much info here, but does anything pop out to anyone in the video?



Active Member
Oh I definitely hear the knocking on the 2nd video. Doesn't sound good :/ sounds like piston slap or rod knock to me. Does it get any better when the engine gets up to temperature?