83 LTD Questions

[Anonymous]

I have an 83 LTD I-6 with the stock carb , no mods at all. Will the weber/holley Pinto carb be better than the stock carb as far as performance? Also , since I can't afford headers, will an earlier model exhaust manifold bolt up to my block as the stock manifold has a huge emmisions cannister on it. Will the older manifold flow better ? just trying to coax a little more HP on a budget. Thanks.

 

[CZLN6]

Howdy Bob:

We recently had a chance to drive an '81 Mustang coupe with a 3.3 and a 4spd OD, and we were more than a little shocked at how gutless it was. It had a factory tach in the dash. It had a very hard time getting up to four grand. It was so different from my stock '65 200, 3spd Ranchero that it was shocking.

I have no idea on it's state of tune, but it had been sitting for quite some time. In trying to figure out the differences we came up with several limiting factors; 3.08:1 rear gear, stiffling exhaust, 8.6:1 compression ratio, EPA feed back Holley #1946 carb, retarded cam timing, possibly a Calif only distributor module.

I listed this items only because I'm guessing that your LTD is encumbered in the same fashion. Yes, the earlier exhaust manifold will fit. I would use a '67 to 69 vintage to avoid the EPA bungs cast onto later exhaust manifolds. It will have a 2" outlet, so build the rest of the exhaust system to match. Check your state laws and EPA requirements on cats, but on a vehicle this old you may be able to get by with an internally clean system.

The Holley/Weber is a nice upgrade, or possibly consider a Carter YF in the 195 CFM model. Check Dougs site for details. The YF will be more of a direct bolt on.

These two changes should make a nice improvement.

Then I'd be looking for a rearend swap to get a better gear. You didn't say what tranny you have, but a 7.5 or 8.8 rearend in a 3.27:1 ratio should be a bunch better. You will likely have a 2.79 or 3.08:1 ratio.

But start right now by increasing your initial advance setting to about 12 to 14 degrees.

Improving the head, and getting a cam timing gear in a straight up position are more involved, but that's where the real power is.

Keep it straight!

Adios, David

 

[Anonymous]

Thanks David,
I have all the problems related to the 80's smog bound engines you mentioned with the exception of the Ca ignition . The car was sold new in FLA. I'm pretty sure the rear gears are 2:79. The tranny is a C-5. I plan to strip all the smog stuff off as we have no smog police here. I am not sure how to go about it so any advice would be appreciated. I get only 18MPG now so would a 3:20 or so rear gear be worth the loss in mileage as far as improving my acceleration ? One more question. Back in the day the inline six guys used to split the manifold to add dual exhaust. The manifold would have another hole torched in it and a pipe welded in place for another exhaust pipe. Could I use this technique with a port divider and get any gain ? I'm also looking for a nice tone with dual turbos. Can't afford headersat this time. Thanks for all your help.
Bob

 

[rbohm]

8) swaping to the stiffer gears, as long as you dont go too stiff, may actually improve fuel economy as your ltd is a bit heavy for the stock 6. if you do lose mileage it will likely be no more than 2mpg. as for the exhaust, you will need to close off the stock outlet and set the new ones about 1/4 of the way in from each end. for the money you will spend though, you might want to shop around for a header instead. however improving the exhaust flow will always improve the hp and torque.

 

[CZLN6]

Howdy Back Bob and All:

I think rbohm is right on. I'd be very surprised if you lost any mileage and not very surprised if you gained some. It will sure be more fun to drive- which may be a factor toward lower mileage.

The C5 should still work better for you. The big difference between a C5 and the traditional C4 is that the C5 has a lock up torque converter and different internal valveing.

As for splitting the exhaust manifold, the middle two ports are siamized together and it is very difficult to split in the traditional 123/456 fashion. Some have split the exhaust in a 1234/56, with mixed results- mostly sound. From a practical stand point a modified 2" outlet manifold with a matching 2" system and a good quality turbo muffler may be simplier, cheaper, lighter and a better performer.

EPA laws are Federal Laws, emforcement is a state issue. You can ask for information and permission now or forgiveness later. Your choice.

Adios, David

 

[BKNLINE]

Another option you might look into later is to change to a manual trans. Although if the '81 Mustang with the SROD was a slug, this may not be too great of an idea.

If you do decide to do this you know the '83 LTD is basically a Fairmont (like the '79-'04 Mustangs) so you can grab the pedals and supports from a '83-'93 Mustangs (I'm sure these fit) and use an aftermarket clutch quadrant.

Bell housing is a prob right now but basically involves modifying an I6 SROD bell to fit a T-5.

With 3.55 rear gears and a V8 T-5 2.97 1st gear (I think), acceleration should be a bit better.

Something to look forward to,

Dean T

 

[Anonymous]

A tT-5 would be cool but I wasn't thinking when I dropped a bundle on a reman C-5 last year. This is my actual car not a project so I went with the quickest solution . I think my first move will be the rear gear probably a 3:27 8.8 or 7.5. Most bang for the buck. Next, get another late head and work it over , so I can keep the car on the road. Ditto with an earlier exhaust manifold 67 or so as suggested. BTW, if anyone has such a manifold let me know and if the price is right I'll buy it. YF carb , single turbo dual outlet. All smog stuff disappears. My tranny man says he can work on the shift points to hold 1st a little longer and give me a firmer shift. Nobody makes a shift kit for a C-5 as far as I know. I had a guy tell me " Why don't you just get another car?" I love my old wagon that's why!
Thanks for all the support . keep it coming.

 

[63comet]

Heh ltdbob, I too run a BB200 out of an 83 ltd, the only difference is I installed it in a 63 comet, I also went with a rebuilt C5, and I don't like the shift points at all, these can be adjusted using your modulator, in the end of your modulator, there is a small slot for small screwdriver, pull off the hose and turn it clockwise to increase the shift points. I am changing to a C4 this winter. They do make a shift kit for the C5, I installed one last winter, but the trouble with the C5 is that the only torque converter you can use is the one that came with it or direct replacement, they don't make a high stall speed TC for it. The problem with the BB200 block is that the C5 is the only tranny you can hook to it without modifying the bell to block mounting as well as fabricating the flexplate. There is an article on how to do this in the tech section. They only made the BB200 from 1980 to 1983 when they discontinued the 200, and the only tranny hooked to it was the C5.

 

[Anonymous]

Would 3:45 gears be considered too stiff? In comparing RPM at 55mph with my tire size, the results are 3:45- 2550rpm, 3:27-2400rpm. My present 2:79-2050rpm. Will I stress my engine too much with these changes ? I have found a 7.5 with 3:45s cheap so therin lies my dilemma.
Thanks for all your help.

 

[CZLN6]

howdy bob:

"Cheap" is always a factor in my decision making process. another question. Do you do most of yur driving around town, stop-and-go, or freeway comutes? If the answer is the 1st go with the 3.45 and juggle tire diameter if you're laking a long road trip.

Your rpm at 55 mph is one thing, but what will it be a 65 or 70 mph. 3.25 is a better all-around compromise with a non-OD tranny. 3.45:1 would be my 2nd choice.

Fortunately, swapping rear ends on these Fox based rigs is relatively easy, so, if it's cheap enough, try the 3.45 and judge for yourself.

Let us know how it works out.

Adios, David

 

[rbohm]

8) i agree, if you are not going to use an o/d trans, and the car will be used on the highway alot, then stick with the 3.27 gears, otherwise the 3.45's would work nicely.

 

[Anonymous]

Thanks All,
The 3:45 rear is $100.00 , 7.5. I found an 8.8, 3:27, $250.00.
BTW 3:45 at 65 3000rpm, 3.27 ,2850
I don't think the 3:27 is common in a 7.5 . Any ideas about that?

 

[Anonymous]

Update: I called the Mustang parts dealer about the 3:45 raer end and he jacked up the price to 150.00. His web site said 99.00 . Old price he said.

Mustang Parts Specialists
Winder , Ga
This sucks!

 

[LEROY POLL]

HELLO LTDBOB

....YOU CAN LOOK IN THE JUNKYARDS. THE AOD V-6'S MOSTLY HAD THE 3.27'S AND 3.45'S. I'VE SEEN THE 3.45'S IN THE STATIONWAGGONS. I'VE FOUND THAT MOSTLY THE MERCURY MARQ. STATIONWAGGON HAVE HAD THIS REAR END. GOOD LUCK HUNTING AND LOOKING.

....I DRIVE A 1983 LTD BB200, W/C-5, 2.73, W/920,000 MILES. I WENT TO LA. CALIF THIS LAST WEEKEND AND GOT 24.3 MPH.

LIVE IN GRACE

LEROY POLL

 

[Anonymous]

920,000 miles!!! SAY WHAT??

 

[LEROY POLL]

THANKS BOB


I DIDN'T CATCH THAT. NO IT'S 92,000 MILES. I HAVEN'T TRUNED OVER YET.

LIVE IN GRACE

LEROY POLL