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Contemplating motor build

Well guys I recently sold a John Deere tractor project of mine and am contemplating using the proceeds to finally build the motor for my T-bird.  My 302 is getting really tired with nearly 200k on the bottom end.  Over the last year it has started using oil and seems to really be down on power.  I also sold my '07 Mustang GT so this and my junky '87 f-250 are my only real hobby now, lol.

What I'm looking for is something that will run on 93 octane pump gas, be reliable enough to take on road trips (power tour, etc), and put a smile on my face when I stab the gas.  I've been hoping to do this someday and have modified the car over the last 10+ years building it up in preparation of throwing more power at it (8.8 swap, control arms, sub frames, exhaust, etc.).

I know there are other forums that might focus more on engine builds, but I thought I'd start here as this is the first forum I ever really joined and have stayed active with through the years, so I feel like I can trust your opinions.

From what I've researched so far I'm thinking: 331 stroker with AFR 165 heads.  No idea on induction.  I'm thinking I could use my current BBK shorty headers and be OK.  I have no idea what to plan for on ignition stuff (do you really need MSD type stuff?) or fuel (I believe my fuel pump is 190lph, no idea if that's enough and what I'd need for injectors).  I'm still speed density as well so I'd have to figure going to MAF.

 Basically I want to get a game plan but really don't know where to even start as I've never done this before!

As far as the machine work, can anyone recommend someone in my area (southern IN)?  Overall budget would be max of $6k, as that's what I sold my other project for but I'd be happy with less. 

Thanks for any suggestions you all may have!
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Contemplating motor build

Reply #1
Honestly if you are building a 331 skip the 165/170cc heads. They are too small for a 331. My buddy has a 331 in his Mustang. He has the following combo. Makes power across the board. I think you'd like it.

331
Trick Flow 190R heads
Holley Systemax intake
Ed Curtis cam
30lb injectors
75mm throttle body
80mm MAF
2.5 inch exhaust

That combo would put a big smile on your face :)
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Contemplating motor build

Reply #2
^^That sounds pretty solid to me. You can only get so much bottom end torque out of 302 CI. Stroker is definitely solid.

I will say, either the blower car or the stick car (or both LOL) is going to have a 351W for its next motor. I need to gather more info but it sounds like with some creative tricks and K-member spacers, one can be made to fit under the stock hood. Which is a requirement for me. But for  cheap you get all that extra displacement and a block that can handle 700-800 hp.
1987 20th Anniversary Cougar, 302 "5.0" GT-40 heads (F3ZE '93 Cobra) and TMoss Ported H.O. intake, H.O. camshaft
2.5" Duals, no cats, Flowmaster 40s, Richmond 3.73s w/ Trac-Lok, maxed out Baumann shift kit, 3000 RPM Dirty Dog non-lock TC
Aside from the Mustang crinkle headers, still looks like it's only 150 HP...
1988 Black XR7 Trick Flow top end, Tremec 3550
1988 Black XR7 Procharger P600B intercooled, Edelbrock Performer non-RPM heads, GT40 intake AOD, 13 PSI @5000 RPM. 93 octane

Contemplating motor build

Reply #3
Quote from: ZondaC12;455043
I will say, either the blower car or the stick car (or both LOL) is going to have a 351W for its next motor. I need to gather more info but it sounds like with some creative tricks and K-member spacers, one can be made to fit under the stock hood. Which is a requirement for me. But for  cheap you get all that extra displacement and a block that can handle 700-800 hp.

The only issue with the 351W is you need a different front accessory dress. Other than that 408W FTMFW!

If I has $$$ I would do a Dart 363 build. It's just so  expensive and not in any way "budget", unless your budget is ~$11k. That's just the engine. Fortunately the transmission/driveline/rear axle/chassis/suspension on my Thunderbird could take it. Otherwise that figure would be more....
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Contemplating motor build

Reply #4
Anyone have suggestions as far as rotating assembly?  I don't think I need forged.  Do most people piece them together or just buy a "stroker kit" from eagle or scat or something?
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Contemplating motor build

Reply #5
I've heard that scat cranks balance a lot cheaper and need less machine work then eagle.

If it were me, I'd go 347 all the way. It costs the same, you can get the same rod ratio and you will make power at lower rpm's.

I'd also skip the afr165's unless you need emissions. Trickflow FAC are the same price or slightly cheaper, have more ptv clearance for a more radical can and can be cnc'd larger if you feel the need to upgrade in the future.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Contemplating motor build

Reply #6
im doing a budget build, found a 81,000 mile motor, replacing all bearings and using arp bottom end bolts, gear drive, gt40 heads and intake, not sure what cam yet, just a cheap daily driver build lol.

Contemplating motor build

Reply #7
With your motor being worn out an well built 302 will put a smile on our face.  Find a 5.0 Ford Explorer or Mercury Mountaineer motor (96 through early 2001) and start with that.  Typically about $500 to $1,000 and it should have GT40 iron heads on the 96 and the early 97 models from there they are GT40P heads.  Pull the motor apart and inspect the bearings, rings, and replace if necessary.  Re-ring the pistons, have a valve job done on the heads and replace the valve springs with the TFS kit (https://lmr.com/item/TFS-2500100/Trick-Flow-50l-302-Mustang-Valve-Springs-Upgrade-Kit).  Replace the oil pump, oil pump shaft, and timing chain for insurance reasons.  I would choose a good cam for the combo like the TFS Stage One or if you can swing it get an Ed Curtis setup (cam, springs, and timing chain).  So now you have a long block for about $2,000 if you bought the motor on the lower end of the scale and no machine work was needed.  Reused the upper and lower intakes and do the aire temp sensor relocation.  Again if you have the $$$ send the lower to TMoss (search the Corral for him) and have him port it to match the heads.  I think he used to charge $100 pluss shipping using your intake.  Reuse the Explorer 70mm thorttle body with the throttle linkage mod the has been dospoogeented all over the place.  So if all goes well you are into this motor for about $3,000 if you do most of the work yourself (no machine work like the heads) and you have about $3,500 left over to find a Mass Air harness, MAF, A9L, associated ducting, injectors (highly recommend 30lb/hr or 36lb/hr as my 306 hit a wall with my 24's), headers (BBK's will work), your accessory brackets and accessories, and maybe some elbow grease and paint.

I am sure I missed a few things but this has been done 100's of times on Mustangs so do a little research and you should have a good game plan.

I would definitely get a custom tune so plan on $500 for the chip and dyno time.  I have seen this combo hit well over 280 rwhp and if tuned right almost 300 rwhp.  My guess is your worn out motor is under 200 rwhp so this would be huge grin factor and it fits the budget.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Contemplating motor build

Reply #8
Quote from: Haystack;455055
I've heard that scat cranks balance a lot cheaper and need less machine work then eagle.

If it were me, I'd go 347 all the way. It costs the same, you can get the same rod ratio and you will make power at lower rpm's.

I'd also skip the afr165's unless you need emissions. Trickflow FAC are the same price or slightly cheaper, have more ptv clearance for a more radical can and can be cnc'd larger if you feel the need to upgrade in the future.

I've always heard of oil consumption issues with a 347?  Not sure if that's 100% always the case though.  Would there be any more costs machine shop wise with the 347 vs 331?
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Contemplating motor build

Reply #9
Quote from: Aerocoupe;455062
With your motor being worn out an well built 302 will put a smile on our face.  Find a 5.0 Ford Explorer or Mercury Mountaineer motor (96 through early 2001) and start with that.  Typically about $500 to $1,000 and it should have GT40 iron heads on the 96 and the early 97 models from there they are GT40P heads.  Pull the motor apart and inspect the bearings, rings, and replace if necessary.  Re-ring the pistons, have a valve job done on the heads and replace the valve springs with the TFS kit (https://lmr.com/item/TFS-2500100/Trick-Flow-50l-302-Mustang-Valve-Springs-Upgrade-Kit).  Replace the oil pump, oil pump shaft, and timing chain for insurance reasons.  I would choose a good cam for the combo like the TFS Stage One or if you can swing it get an Ed Curtis setup (cam, springs, and timing chain).  So now you have a long block for about $2,000 if you bought the motor on the lower end of the scale and no machine work was needed.  Reused the upper and lower intakes and do the aire temp sensor relocation.  Again if you have the $$$ send the lower to TMoss (search the Corral for him) and have him port it to match the heads.  I think he used to charge $100 pluss shipping using your intake.  Reuse the Explorer 70mm thorttle body with the throttle linkage mod the has been dospoogeented all over the place.  So if all goes well you are into this motor for about $3,000 if you do most of the work yourself (no machine work like the heads) and you have about $3,500 left over to find a Mass Air harness, MAF, A9L, associated ducting, injectors (highly recommend 30lb/hr or 36lb/hr as my 306 hit a wall with my 24's), headers (BBK's will work), your accessory brackets and accessories, and maybe some elbow grease and paint.

I am sure I missed a few things but this has been done 100's of times on Mustangs so do a little research and you should have a good game plan.

I would definitely get a custom tune so plan on $500 for the chip and dyno time.  I have seen this combo hit well over 280 rwhp and if tuned right almost 300 rwhp.  My guess is your worn out motor is under 200 rwhp so this would be huge grin factor and it fits the budget.

Sounds like a very affordable way to go.  I'm just afraid that if I don't go ahead with a stroker and aluminum heads etc, I'll regret it down the road.  I'm not going to change things up every few years, this motor would be powering my car for many years (decades even) to come.

So is it unreasonable to think I can be in the $6k range for an aluminum headed 331?  Thanks for the insight fellas.
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Contemplating motor build

Reply #10
I built my 331 on what I called a budget and spent right at $10K.

The oil consumption issue with the 347 was due to the wrist pin location on the pistons being in the oil ring groove.  Most companies have since addressed that issue to that is something of the past.  There are still some that complain of piston slap when the motor gets some miles on it so that is why I chose the 331.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Contemplating motor build

Reply #11
Ok thanks.
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Contemplating motor build

Reply #12
What ever you decide to do I would skip the iron GT40/GT40P heads and GT40 intake. I went that route and replaced both those pieces within a few years as it just wasn't enough. The Edelbrock Performer heads and Edelbrock Performer RPM intake are so much better it's like night and day. Based on track testing the engine gained around 50hp over the GT40P heads and GT40 intake that were on the car previously. Plus driveability is vastly improved. I can tell you from experience that you will not be happy with the iron GT40 heads and GT40 intake.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Contemplating motor build

Reply #13
Ok good to know.  I am kind of overwhelmed right now as I read online about all the different combos out there.
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Contemplating motor build

Reply #14
My old 351W DOZZ headed and Cobra intaked 306 with a TMoss port job but down 289 rwhp. Being that an Explorer motor or Mountaineer motor would come with them it would be hard to justify buying a set of heads and intakes to gain any possible hp gain. I can tell you I had a very nice cam in that motor and it would pull the 6,000 rpm chip through the gears in a very hasty manner. So I finally decided to up the combo and went to a set of Edelbrock Performer heads and Edelbrock Performer RPM II upper and lower and gained a whopping 19 hp with the 306.  Now this was done as I knew I was going to a stroker down the road.  I have not dyno'd the 331 but let's just say there is simply no replacement for cubic displacement.

Everyone wants to know if the 331 was worth the additional $$$ over a built 306. Kind of a loaded question but for me it comes down to cubic dollars. If you have a limited budge then the answer is no being that there are still Explorer motors out there that make a built 302 just too  economical. If I was starting from scratch with a bare 302W block and the funds were there for a stroker then I would build a 331 or 347 hands down. I built the 331 for longevity as it has a better rod angle than the 347 but if your not going to drive a car much build a 347.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp