I feel it's time to do something to my 85 gt t top , need suggestion please

[Sinister]

Hi every body , I am getting bored to keep my 85 gt top stock form , I want some POWER !! I want it to have power and drive on street or track when ever I feel like it . Like some day I can just put in a drag tires and go track , or put back my 10 hole for stock form look .

1: full 5.0 coyote swap ( automatic )
2: build my stock 5.0 up with automatic with a beefy rear end . Beef up the suspension .

Those are 2 idea I have . I kinda like #2 . If I want build up my 5.0 . What size I should stroke to without making the wall to thin and still on safe side . My goal around 400-500whp on pump gas . I want automatic , which automatic transmission should I use . Also rear end I want keep it 4 lugs . Which years of rear end 8.8 should I use ?

My goal plan in life is keep my 85 gt and build it up and buy a 2017 mustang gt 5.0 black to match my 85 gt . That pretty much it in my life . Imma keep this combo til I dead . With 2 door garage I want put a lift on it . And keep my 85 on top and my 2017 on bottom . Other side on gargebis my wife car.

Any suggestion is welcome . Thank you and have a wonderful day -Sinister-

[erratic50]

The swap to more modern engines is quite overpriced when you look at power output and weight vs dollars spent.

What has always been so appealing about the foxbody is how well they take to basic and simple mods.

Personally I'd start with tubular upper and lower control arms and some rear gears. 4.10's or 3.90's if you run an automatic, 3.73:1 with a factory 3.35:1 T5.

Next, get more RPM out of your engine. That stock intake belongs on a shelf. An intake and headers and open exhaust will add fun initially, but may leave you hungry for more power. There is power to be had in stock heads by raising the compression via planing as well as in porting. But aftermarket heads have more to offer.

If the stock bottom end is in decent shape consider adding some trick flow twisted wedge heads, a wisely selected cam, and a good 4 barrel intake. This would really wake it up. Don't go cam crazy - many builds prove a degreed in stock cam with a decent intake and 1.7:1 rockers and headers will reward you with quite a bit of performance. An area under the curve motor will give the best overall performance and be the most fun to drive too.

You could Find a reputable shop or do a lot of reading and build what is essentially a known performer so you don't waste time and money.

If it's well worn then bore it 0.030 over otherwise leave it at standard bore. Add some stroke. 4.030 x 3.25" stroke is a 331.

If you do stroke it, here is how you can get displacment:
BoreXBoreXStrokeX.7854XNo. of Cyclinders
4X4X3X.7854X8= 301.5936

If you search the net you can find day by day run by run details of guys who bought their fox new and raced them starting with a stock unmolested car and going after ETs.

those articles will tell you stuff like this:Disconnect front sway bar before runs
Relocate battery
(Good) 26x8 slicks or (better) 28x94" Skinnies up front
Tubular upper and lower control arms
Loosen bar and jack Rear sway bar- biased to passenger rear
Subframe connectors
Performance dual plane or EFI intake
upgraded air filter
cold air kit
(EFI cars - 65MM throttle body & spacer, 70 MM MAF meter, remove silencer)
RAM air setup
Underdrive pulleys
Short belt
Electric fan
New plugs
Timing advance to 14 degrees
4 cyl rear springs
3.90 gears
T5Z transmission
RAM clutch
Equal short headers
Exhaust dumps before cats
Ice intake before runs
Hurst shifter
Upgraded cam such as Comp cams 270HR

All this stuff is straight like performance oriented. If you want a road course car you need to go towards proven mods in that space. Gears and control arms are still where to start but get adjustable rears.
Stock motor is plenty until chassis is addressed
Strut tower brace
lower K member brace
panhard bar or watts link
Ackerman corrected spindles such as SN95
double adjustable sn95 shocks, removed stock fox bumpstops
double adjustable foxbody struts
rear disc brakes
better front brakes
performance friction brake pads
larger diameter wheels such as 17x8 or 17x9.
corner carver tires
torque arm rear suspension
lower center of gravity with better suited springs or coil overs
more power under the hood

Etc

enjoy building your dream car!

[Sinister]

I really want get rid of the t5. I want a automatic .

[wraithracing]

I have to disagree with the tubular upper and lower rear control arms. If you are going to drag race the car only, then it might be ok. For a car that will be street driven you need the stock upper arms with good rubber bushings to prevent the rear suspension from binding up while cornering, etc. Unless you are going to a full Torque Arm setup, but then you ditch the upper control arms anyway. Keep the stock uppers, replace all the upper bushings with NEW RUBBER bushings. Buy a set of Maximum Motorsports rear lower control arms (chose your arms based upon your power output) and that will make a huge improvement both at the track and on the street. A panhard rod would be another excellent addition to the rear suspension.

400-500 RWHP will be tough without a power adder such as a Turbo or Supercharger. If staying with the SBF, then I would most likely recommend a 347 stroker as there is no replacement for displacement. You can also go to a 351W or even a 460 based swap, but your costs and time will generally go up due to the additional parts needed for the swap. Not saying they aren't a great option, but you will need to buy things for either swap that you don't have to when keeping your 5.0 based engine.

As for an automatic, most likely a well built AOD with the right convertor will do what you want and essentially be a bolt in. If you don't need/want an overdrive then you can always use a C4 or C6. A 4R70W is another option as basically a computer controlled AOD, but that will add costs and parts to the build. I am a stick shift kind of guy, so none of my Foxes run an automatic so that is about all the help I can be.

IMHO you are going to have a hard time getting to your power desires and keeping the car streetable/cruiser like without going to EFI. Yes, you can get tons of power out of a carb and often a bit more than EFI, but EFI generally rules on the street when it comes to driveability. Especially when you are trying to pull 400-500 RWHP out of a SBF. With that considered the swap to the Coyote 5.0 might not be a bad idea.

If you can find a relatively inexpensive Coyote and do most of the work yourself, then the overall cost may be very similar to building up a 347 EFI engine. You are going to need to be frugal, but in some ways that might be the better option. I would recommend doing your research and a lot of planning before making any decisions. The Coyote is an awesome engine and has some huge benefits, but there are some headaches to a swap such as that too. Good Luck!

[Fastlane]

I would do what others have suggested, start with mods that you won't have to "redo later", like lower gears in the rear-end, rear lower controls such as the MM adjustable's, but like Wraithracing mentioned, use the stock upper control arms in the rear-end unless you plan on drag racing. I once installed upper and lower boxed control arms for the rear-end and had a bad binding problem. At first I thought maybe I had torqued the bolts too tight, but it didn't matter what I did it continued to bind. Worked fine going in a straight direction, but once you went into a turn you could feel the rear end binding up.
Once the upper control arms were replaced with stock ones, no further binding and lower boxed arms still worked much better then the flimsy stock arms.

[Sinister]

the rear end have to go. I dont want put moneys on the weak 7.5 ( even though nothing is wrong with it, its perfect condition ). I would like do the 8.8 swap but keep the 4 lug style.

[4eyedfoxdriver]

Maybe I missed it, but first what is the budget?

Second realistically how fast do you want it to go?


Third how important is the driveability?

[82GTforME]

Any suggestion is welcome . Thank you and have a wonderful day -Sinister-

If you remove the headlight louvers and sell them to me, you will go faster with less drag and weight

Thanks for popping in again!

[wraithracing]

the rear end have to go. I dont want put moneys on the weak 7.5 ( even though nothing is wrong with it, its perfect condition ). I would like do the 8.8 swap but keep the 4 lug style.

Any Mustang V8 8.8 rearend from 86-93 will bolt right in. You could also use the 94-98 8.8 rearend and just swap all your 4 lug axles, etc. over.

[Supersonic G.T.350]

I'm really interested in the budget myself. Suggestions and opinions are free but if we have no budget to work with them it becomes difficult to make reasonable suggestions. I could easily say order a Dart based 363 with huge heads, custom cam and what the hell, let's throw some turbos at it too and we could make some HUGE power but we'd also spend over $10,000 to do JUST that.

[Sinister]

If you remove the headlight louvers and sell them to me, you will go faster with less drag and weight

Thanks for popping in again!

Lol some day , you looking one now too ? My next person on the list is the dude with the red Saleen ( forgot his name , it's been a while )

[Sinister]

I also think build up and use what I already have now . Pull the motor and rebuild it to 306 mabe 300-320hp ? Keeps the t5 and rear end . Put in an c4 or over drive transmission . Replace the 7.5 with the 8.8 when it break . Beef up the suspension , upgrade as I go . For now my budget on the motor is 5k. Wonder how much to stroke my 5.0 to 306 , some day I also want add a super charge too .

[4eyedfoxdriver]

You don't need to stroke it to 306, it just needs a bore. I would think 1500-2000 on the shortblock rebuild.

5k should get you a nice 306. I would do pistons for Twisted Wedge heads and the 170's. A custom cam, RPM intake , 600 mechanical secondary carb, headers and exhaust.

[Sinister]

Any Mustang V8 8.8 rearend from 86-93 will bolt right in. You could also use the 94-98 8.8 rearend and just swap all your 4 lug axles, etc. over.

How much them 87-93 v8 8.8 usually cost. Anyway you can tell its from a v8 ?

[Supersonic G.T.350]

All 86-93 5.0 cars had an 8.8. it's easy to identify, basically it looks just like your 7.5 just bigger, lol! When you look at the diff pan you should know immediately that it's no Mickey Mouse 7.5.

[Sinister]

All 86-93 5.0 cars had an 8.8. it's easy to identify, basically it looks just like your 7.5 just bigger, lol! When you look at the diff pan you should know immediately that it's no Mickey Mouse 7.5.

then what those 4 cylinder 87+ having ? I have my 98 GT out side, I look at the rear diff, they both does look different .

Edit : I forgot to add, a while back I came across this 1 OWNER 98 GT pure white Stock complete ( 6 cats ), run perfect, everything work, no check engine light. pure white, its remind me alot of my very first mustang is black 98 gt, I been looking for my old 98 gt for few years now, but no luck, this is perfectly replace that. That pretty much reason why I bought it, even though I have NO ROOM. I just have to fit this one in. My daughter grew up in my black 98 gt , from prenancy to first day of school..., I had a pix of her when she 1 years old sitting on top of the trunk, now she grown, imma take another pix of her on the trunk of this mustang lol. anyway....

[erratic50]

A key point about what I said above - pay attention to the comments from others on bushing types on upgraded control arms. You can decrease bind with a panhard or eliminate that problem with a watts link. If you don't pay attention you will ruin your torque boxes.

Battle Box reinforcements or aftermarket boxes have some advantages but they get expensive really quickly.

I am a huge fan of torque arms in both road race and 1/4 mile applications up to the point that they no longer provide the desired results. The chassis setup is very different when going torque arm vs control arms because the weight transfer characteristics and braking characteristics are so very different.

They are are an awesome setup when done right.

If you want an automatic I would go period correct AOD from a 1987-1993 V8 Mustang. Then beef it as you build it how you want it.

I agree - EFI is a very wise investment. Do your homework first.

Sometimes people get sick of pedal effort associated with a clutch. That can be fixed with more modern clutch setups and hydraulics, etc, if that's your reason for ditching the stick.

[Supersonic G.T.350]

then what those 4 cylinder 87+ having ? I have my 98 GT out side, I look at the rear diff, they both does look different .

Edit : I forgot to add, a while back I came across this 1 OWNER 98 GT pure white Stock complete ( 6 cats ), run perfect, everything work, no check engine light. pure white, its remind me alot of my very first mustang is black 98 gt, I been looking for my old 98 gt for few years now, but no luck, this is perfectly replace that. That pretty much reason why I bought it, even though I have NO ROOM. I just have to fit this one in. My daughter grew up in my black 98 gt , from prenancy to first day of school..., I had a pix of her when she 1 years old sitting on top of the trunk, now she grown, imma take another pix of her on the trunk of this mustang lol. anyway....

Notice I said all the 5.0 cars from 86-93. The 4cyl cars have a 7.5 just like your 85. The 98 GT that you're talking about will have an 8.8 from the factory. It's pretty much a bolt in for your car minus the brake lines being different because of the rear discs. Your axles will slip right in so you can swap over your backing plates, use your brakes and axles and if your careful swap your brake lines over. Hope that helps.

[Supersonic G.T.350]

Also, like everyone else has mentioned concerning suspension and upper control arms. You want something that is able to articulate. I chose these and they seem to be very well constructed.
http://www.jegs.com/i/JEGS-Performan...64508/10002/-1

[Sinister]

The aod from 87-93 will bolt right up to my 85 gt .

[erratic50]

Supersonic- those are sweet! Adjustable for an actual 4 wheel alignment and setting correct pinion angle in lowered cars too.

im still trying to talk myself out of a beefy torque arm setup instead. Well - I don't think I will. It's hard to argue with no more brake dive and better weight transfer, etc.

I still love watts links although I bought a MM panhard bar because they are simpler and 99.9% as effective.

Better gears, longer A arms or wider K member, X2 ball joints and SN95 spindles and 99+ GT or 2003-2004 cobra front brakes, SN95 rear diff and brakes, adjustable proportioning valve caster/camber plates, tubular lower control arms, and a torque arm plus panhard would give an outstanding transformation for the money. Add double adjustable SN95 rear shocks with fox bump stop deletes and 93 LX rear springs, and adjustable struts. All together that would make one hell of a fun driver!