Fox T-Bird/Cougar Forums

Technical => Engine Swapping => Topic started by: Chooglin on September 15, 2007, 11:24:12 AM

Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on September 15, 2007, 11:24:12 AM
Let me start by telling you what car this 302 will being going in.

Its a 1983 T-Bird with a carbed 3.8 engine and a c5 tranny.

I would like to know what some of the [COLOR="Red"]major problems[/COLOR] I should expect to run into, while doing this swap.

these are the things I can think of that would be a problem and I need the solution to them.

1) moving the motor mounts

2) using the wire harness that is currently in the car.

3) will the k-member work with this swap?

4) drive shaft length after swap.

5) header clearance issues?

6) hood clearance issues ?

These are the things that I am aware of that need done.

1) oil pan needs changed

2) c5 tranny will not handle abuse (will be changed in the future)

3) 7.5 rear end will not handle abuse (will change in the future)

4) radiator swap

this will not be a high HP engine (220 to 250 HP) so I am not to concerned about the rear end or tranny rite now.

I would really like to hear from the ones that have done this type of swap or that are really knowledgable about this. (not the ones that
"THINK" they know what needs to be done.

I have the will and capability to do this, but I dont want to get to deep into it, if it is going to be more headaches than its worth.

Thanks for the input.
Title: carbed 3.8 to carbed 302 swap
Post by: 84 Fila on September 15, 2007, 12:02:59 PM
Going down your list of things I know:
#2. If you go a simple duraspark box, you can use the stock harness. You have to do alittle splicing but it's not bad. Me and Carl have both done this.
 
#5. It depends on the headers. I have a wild set of Mac equal legnth shorties and they clear, but bearly. If your going stock stang shorties or the like you will have no problems but you MUST use an H pipe
 
#6. Depends on the intake and carb combo. With you HP level you want, I don't see any reason for a huge intake and a 2" spacer. You'll be fine
 
For the stuff I'm not %100 on,
 
#1. I don't think you have to move the motormounts, but just buy the V8 ones.
 
#3. A big I duno
 
#4. I'd assume you just get one from a V8 car
 
Hope I helped in some way
Title: carbed 3.8 to carbed 302 swap
Post by: 88turbo on September 15, 2007, 12:14:55 PM
what model of car are you getting the 302 from?  if you find a bird that originally had a 302 you should be able to use its driveshaft.  I'd think that you would be swapping engine and tranny at once or during the swap k-member should be the same for the 302.
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on September 15, 2007, 12:30:32 PM
Quote from: 88turbo;176435
what model of car are you getting the 302 from?  if you find a bird that originally had a 302 you should be able to use its driveshaft.  I'd think that you would be swapping engine and tranny at once or during the swap k-member should be the same for the 302.


the motor originally came out of a 1969. when I purchased the motor,it was pulled out of a 1977 car.
Title: carbed 3.8 to carbed 302 swap
Post by: dudeman351 on September 16, 2007, 05:39:42 AM
v-6 v-8 i 4 k member are the same. i-6 k member is a beast all to its own. the driveshaft should work the trans doesn't move at all from the swap. if you have your orignal k-member in the car and not an 85-88 use mustang motor mounts. in all actuality this swap is on the easy side of the scale. if you already have a duraspark ignition in the car use your box and coil and hook it up to the v-8 distributor. good luck dude.
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on September 16, 2007, 07:43:56 PM
Thanks Dude,this may not be as bad as I thought.

One more ? .is it possible to use the alternator,power steering pump and the pulleys with the swap?
Title: carbed 3.8 to carbed 302 swap
Post by: 84 Fila on September 16, 2007, 07:46:39 PM
If not, I have an alternater bracket, power sterring pump, water pump pulley and I think an AC compresser for ya if you want.
Title: carbed 3.8 to carbed 302 swap
Post by: thunderjet302 on September 17, 2007, 02:17:46 PM
Quote from: Chooglin;176433
Let me start by telling you what car this 302 will being going in.

Its a 1983 T-Bird with a carbed 3.8 engine and a c5 tranny.

I would like to know what some of the [COLOR="Red"]major problems[/COLOR] I should expect to run into, while doing this swap.

these are the things I can think of that would be a problem and I need the solution to them.

1) moving the motor mounts

2) using the wire harness that is currently in the car.

3) will the k-member work with this swap?

4) drive shaft length after swap.

5) header clearance issues?

6) hood clearance issues ?

These are the things that I am aware of that need done.

1) oil pan needs changed

2) c5 tranny will not handle abuse (will be changed in the future)

3) 7.5 rear end will not handle abuse (will change in the future)

4) radiator swap

this will not be a high HP engine (220 to 250 HP) so I am not to concerned about the rear end or tranny rite now.

I would really like to hear from the ones that have done this type of swap or that are really knowledgable about this. (not the ones that
"THINK" they know what needs to be done.

I have the will and capability to do this, but I dont want to get to deep into it, if it is going to be more headaches than its worth.

Thanks for the input.


Even though I have a V8 car I can answer a few things.

You should be able to use mounts for a Fox Mustang that has a 302. The K members in the Birds were the same as the Mustang up to 85.

Headers will be a beast all their own. Most of them should clear the Mustang style mounts. The problem will be you shifter. If you have a column shift it could get trickey. I have FMS stainless shorties and a Summit 2.5" H-pipe and they barely fit around the column shift linkage. You can pretty much get anything to fit as long as you're willing to play with it a little bit.

You should have no hood clearance issues as long as you don't use a huge tunnel ram intake or something similar:hick: .

Just wondering but what are your plans for the engine? What heads/cam are you planning on using? If you don't plan on going crazy the 7.5 might hold up fine for awhile. Me and V8Demon (who runs a TrickFlow top end kit) are running 3.73 Traction-Lok 7.5s behind our engines with no problems (so far:hick: ). If you're going to use slicks on the 7.5 you more than likely will break it but for street driving you should be ok.
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on September 17, 2007, 04:14:12 PM
Thanks for the info Thunder !!!!!

the engine will be pretty close to stock.I would like to have a cam with a slight lope (nothing crazy).

I really appreciate the help guys. As I get closer to doing this, I will have plenty more questions.just trying to get a idea what is going to be involved in this swap.
Title: carbed 3.8 to carbed 302 swap
Post by: dudeman351 on September 17, 2007, 09:24:41 PM
all you need to to is ask. remember the only dumb question is the one that isn't asked.
Title: here you go...i just finished my exact swap
Post by: screaming306 on September 28, 2007, 08:43:40 AM
i got an 84 t-bird that was t.b.i. v-6 with a.o.d.  i bought for $40.00 a parts car from local junk yard. and rewired from bumper to bumper with an 83 wiring harness that was carb. v-6 and c-5.  i put in my t-bird a 302 (0.30 over) and a c-4 trans. holley 600 , -8 fuel line from tank to reg, then carb. take a look at cardomain look for an 1984 thunderbird with about 70 pics or so from grand bay alabama. i would be more than happy to help you with whatever info you need. :birdsmily: :birdsmily:
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on September 30, 2007, 02:43:43 PM
Quote from: screaming306;179360
i got an 84 t-bird that was t.b.i. v-6 with a.o.d.  i bought for $40.00 a parts car from local junk yard. and rewired from bumper to bumper with an 83 wiring harness that was carb. v-6 and c-5.  i put in my t-bird a 302 (0.30 over) and a c-4 trans. holley 600 , -8 fuel line from tank to reg, then carb. take a look at cardomain look for an 1984 thunderbird with about 70 pics or so from grand bay alabama. i would be more than happy to help you with whatever info you need. :birdsmily: :birdsmily:



Thanks for the Info Scream..........PM sent
Title: carbed 3.8 to carbed 302 swap
Post by: thunderjet302 on October 01, 2007, 11:13:35 PM
Just wondering but what do you plan as far as H/C/I? I'm just currious that's all:D
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on October 02, 2007, 04:08:34 PM
H/C/I?.................. Head/cam/intake?

If this is what your asking.It will pretty much be stock.I will change the intake (four barrel carb).stock heads,mild cam.

I talked to a guy that I know, who has a shop down in Tennessee.I will be taking the motor down there on October 28.

these guys know alot more about what I want and need,more than I do,so I will let them handle it.I will bring it back to Ohio and finish it up here.
Title: carbed 3.8 to carbed 302 swap
Post by: thunderjet302 on October 02, 2007, 10:20:10 PM
Quote from: Chooglin;180292
H/C/I?.................. Head/cam/intake?

If this is what your asking.It will pretty much be stock.I will change the intake (four barrel carb).stock heads,mild cam.

I talked to a guy that I know, who has a shop down in Tennessee.I will be taking the motor down there on October 28.

these guys know alot more about what I want and need,more than I do,so I will let them handle it.I will bring it back to Ohio and finish it up here.


Yep H/C/I = heads/cam/intake :D

Sounds like a plan. It should be reliable with stockish parts. Probably run much better than the 3.8 it has now:D
Title: carbed 3.8 to carbed 302 swap
Post by: jcassity on October 05, 2007, 11:32:58 PM
Quote from: screaming306;179360
i got an 84 t-bird that was t.b.i. :


ford did not make tbi systems :hick:  perhaps your bow tie 2.8 has you confussed.
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on November 10, 2007, 07:01:41 PM
little update on this

I took the motor down to Tennessee and they are ready to machine it.

I need a answer to a few questions about the c5 tranny.

*will the bell housing from my 3.8 bolt up to the 302 and if it wont,wich bell housing do I need to look for that will bolt up to the c5 and the 302?

*will the flex plate from the 3.8 bolt up to the 302 and if it wont,wich flex plate do I need to get to work with the 302 and the c5 tranny?

thanks for any help
Title: carbed 3.8 to carbed 302 swap
Post by: blu84302 on November 11, 2007, 04:52:46 AM
I know the bellhousing for a 3.8 and 302 are the same.  However someone else will have to help with the flexplate.
Title: carbed 3.8 to carbed 302 swap
Post by: screaming306 on November 11, 2007, 11:23:31 AM
no..no... the flex plate WILL NOT work. i used a flexplate from a 1990's lincoln town car, actually, any car with a 302 and the early stlye a.o.d. transmission will work. I installed mine, and the holes matched the torque converter on my C-4 . then went to junky yard and bought the nice SMALL starter that comes on the V-6 mustangs anything after 1994. and it also fit the teeth and the block and the bellhousing. i was actually quite surprised.
Title: carbed 3.8 to carbed 302 swap
Post by: screaming306 on November 11, 2007, 11:27:04 AM
jcassity, is the 1984 -1986 V-6 t-birds and cats not throttle bodied injected with to fuel injectors sitting on top of the throttle body????? c.f.i. yes.......t.b.i. just describing the style of injection. or maybe i'm wrong. but when you look in manuals, and try to buy one from the parts house they call it t.b.i. ?????  who knows???? great now i'm lost...
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on November 11, 2007, 11:29:39 AM
thanks guys

Scream,would the starter off of my 3.8 work,if I get the flex plate that you mention?
Title: carbed 3.8 to carbed 302 swap
Post by: thunderjet302 on November 12, 2007, 11:35:04 PM
IIRC pre 83 302s used a flex plate that has a 28.8 oz imbalance. 83 and up 302s used a 50 oz imbalance flex plate.
Title: carbed 3.8 to carbed 302 swap
Post by: screaming306 on November 13, 2007, 12:00:04 AM
get a flexplate and balancer for a 1985 and up block. better get the block too. NO the 3.8 old style won't work. but the 3.8 starter for the 3.8 1994 and up mustangs will. the newer style starter is alot smaller and lighter, plus it is a permanant magnet type of starter. i have no problem cranking my bird with it. oh yeah also get the starter wires too for the mustang. as you will see the you will end up with a solinoid on the starter and one on the wall. i will take some pictures of mine tomorrow and post them for you...did you look on my cardomain. i think there are some pictures there of the pieces too. :D
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on April 06, 2008, 03:17:52 PM
Engine is out
Title: carbed 3.8 to carbed 302 swap
Post by: Chuck W on April 06, 2008, 05:16:57 PM
Quote from: thunderjet302;187353
IIRC pre 81 302s used a flex plate that has a 28.8 oz imbalance. 81 and up 302s used a 50 oz imbalance flex plate.


Fixed
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on April 11, 2008, 08:34:58 PM
engine is pretty much ready to go in.now I need to clean up the engine bay and paint it.
Title: carbed 3.8 to carbed 302 swap
Post by: thunderjet302 on April 12, 2008, 08:09:14 PM
Looks good :D

Where's the Ford blue block and heads? ;)
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on April 12, 2008, 09:39:38 PM
Quote from: thunderjet302;213734
Looks good :D

Where's the Ford blue block and heads? ;)


well,I almost went with blue, but decided to keep everything black,white and chrome.
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on April 20, 2008, 07:27:43 PM
engine bay is almost ready.I hope to be dropping the motor in next weekend.
Title: carbed 3.8 to carbed 302 swap
Post by: thunderjet302 on April 21, 2008, 11:51:56 AM
Looking good :D
Title: carbed 3.8 to carbed 302 swap
Post by: blu84302 on April 22, 2008, 12:52:12 AM
looks good!  Keep the progress going!
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on April 26, 2008, 11:41:44 PM
engine is in...............man I am glad that it done.
I have most everything hooked up and hope to fire it up next weekend.
Title: carbed 3.8 to carbed 302 swap
Post by: daboss351 on April 26, 2008, 11:54:39 PM
looks good!!
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on April 27, 2008, 09:48:54 PM
fired up the engine today

http://www.youtube.com/watch?v=Wl_7zjPFF6s
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on April 29, 2008, 08:27:44 PM
Guys,I need help badly.I am ready to throw a wrench at this car.

I bought a summit h pipe http://store.summitracing.com/partdetail.asp?autofilter=1&part=SUM%2D640725&N=700+0&autoview=sku

this thing comes no where close to fitting.it is way to long,the hangers are about 6 inches to far back.

wich one will bolt up to this properly?I am running shorty headers on a 302 in a 1983 thunderbird

A summit link would be nice.I want to return this one tomorrow and get the rite one.

thanks for any help
Title: carbed 3.8 to carbed 302 swap
Post by: TurboCoupe50 on April 29, 2008, 08:39:46 PM
That pipe should be the correct one... What headers are you using???
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on April 29, 2008, 08:45:50 PM
http://store.summitracing.com/partdetail.asp?part=HED%2D88380&view=1&N=700+150+4294839039+4294908331+4294840126+4294925044+
Title: carbed 3.8 to carbed 302 swap
Post by: TurboCoupe50 on April 29, 2008, 10:33:41 PM
I dunno for sure, but I don't believe there is a off the shelf pipe that fits your headers...

That H pipe fits shortie headers like the BBK 1515 that I have, as does every other '86-93 H or X pipe......

(http://www.jegs.com/images/photos/100/129/129-1515.jpg)

Quite a difference from your headers

(http://static.summitracing.com/global/images/prod/large/hed-88380_w.jpg)
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on April 30, 2008, 12:22:14 PM
thanks a ton Turbo

now that you have posted those pics,I see why the h pipe doesnt work.now I need to figure out what to do about it............lol
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on May 02, 2008, 09:22:46 PM
well I went ahead and bought the BBK shorty headers and they have a much better fit.I now have plenty of clearance and the h pipe fits much better (thanks turbo) but I still have a issue with the hangers.
they are still coming up short.they are hanging by about a 1/4 inch.I decided that I am going to have them moved ,to solve that problem.

another issue ,is the cross pipe ishiznitting the counter weight on the tranny.what is the purpose of this big ugly thing and can it be removed,without it causing a problem?
Title: carbed 3.8 to carbed 302 swap
Post by: TurboCoupe50 on May 03, 2008, 12:48:37 AM
Glad things are working out, that's going to be a nice ride...

Toss the counter weight...

Are you using a hanger for '86-'93 Stang??? If so it's off set and can be made longer by turning it 180*... If not you need one... I bought mine from one of the Stang suppliers...
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on May 03, 2008, 08:17:30 AM
the hanger is on the cross member for the tranny.this is where the old exhaust was hanging,so i figured that is where this one should hang from? is there another way I should be doing this?
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on May 03, 2008, 08:21:52 AM
the area circled in red,is the hanger I am talking about.
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on May 03, 2008, 10:44:20 AM
ok I solved the hanger problem.I removed the hanger from the tranny and made up two exstensins..........fits perfect now.


now I need to know the thread size of the two O2 sensor bungs?
Title: carbed 3.8 to carbed 302 swap
Post by: TurboCoupe50 on May 03, 2008, 11:18:29 AM
Quote from: Chooglin;216967

now I need to know the thread size of the two O2 sensor bungs?


I'm 99% sure they are 18mm, same as the old Ford spark plugs of the 60s(what my Cobra Jet uses)...
Title: carbed 3.8 to carbed 302 swap
Post by: Chooglin on May 03, 2008, 12:15:35 PM
Quote from: TurboCoupe50;216977
I'm 99% sure they are 18mm, same as the old Ford spark plugs of the 60s(what my Cobra Jet uses)...


ok,thats what I thought to,but wanted to double check with someone............thanks again Turbo,for the help.