M-II weak components for drag racing?

stock50LX

Curmudgeon
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Oct 2, 2001
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University Place, WA
I am accustomed to Fox bodies so this is new territory for me. I know the II uses C-4's (good). Are there anyproblems with the smaller bellhousing regarding parts availability and strengthening the C4 for track use?

1. Are parts (especially posi units and varied gear ratios) available for the 8 inch rear? Can it be made to take the power needed to run 12's or 11's?

1a. Are there any 8.8's or 9 inch rears that are bolt ins?

2. What do you guys do about subframe connectors (I assume the frame must be made more rigid)?

3. Anything else I should know about the unique attributes of the II?

4. What does the coupe actually weigh on the scales? (Curb weight is listed at 2640 but I think that is without fluids and some other essential items).

I haven't bought the car yet, but I intend to, at this point; so, answers to these questions are important

Thanks in advance.
 
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1- The 8" is a good strong rear for basic racing. There aren't a lot of options as far as diffs for it, but you CAN get them. There is no bolt in 8.8. Some say a 9" from an early Mustang will bolt in, others claim some slight modification. Do a search on this forum, it's been discussed many times.

2- There's a guy on ebay who makes a nice set of II subframes, in both weld on and bolt on. I have the weld on's on my one car. Just do a search under mustang ii and they'll come up.

3- The II is a good solid car. Much stronger than the fox body, contrary to what people think. There are lots of front brake options out there, due to the II front end being very popular in the street rod scene.

4- As mentioned, these cars are solid for thier size. A typlical V8 car is in the 3k-3200 range. However adding some lightwieght parts like rims and aluminum heads and intakes helps shed a few pounds. Some guys on this forum have reported their V8 cars being under 3k on scales however.

It's a good car, and very popular for bracket racing. The biggest challenge with the cars is the small engine bay size. Headers and bigger engines and different transmissions and such are tricky. But stick with this forum and you'll learn how to get around all the obsticles.

Oh, and here's a shot of our II "race car" :D...

roller1.jpg
 
Posi units are available,so are aftermarket units for the 8in.
Subframe connectors are available,and get them if your gonna run 12's.
8.8 does not swap in. you have to change the whole rear for that,likewise the 9in.
I believe the Lincoln Versailles is a direct whole rear 9in swap.
C4's can be shift kitted also.and hold up surprisingly well.
I would also stiffen up the rear springs too,extra leaf,traction bars,whatever else.
The weight is usually around the 2800lb mark.

RATS, Power beat me to the punch by one minute!
 
Thanks for the info. I was planning on Southside Traction bars already. I knew the stock springs wouldn't get it done. I have a 351W ready-to-go, in my garage, but I don't want to make a car that is miserable to work on (My EFI Fox is bad enough), so I'll probably stick with the 302. It's going to be so nice not to worry about all the EFI sensors, etc.

Are the fuel lines in the II big enough? I assume I need an electric fuel pump.

It will be a bracket car. I assume that Summit will be a good source for parts. Are there any other specialty sites or retailers I should know about? I have lots of experience with Windsor family engines. I need Mustang II and C4 information from you guys. Any problem areas I should focus on when I look at the car one-more-time before buying?

Tell me about your white car. I cannot even discern what's on top of your engine -super charger??
 
stock50LX said:
Thanks for the info. I was planning on Southside Traction bars already. I knew the stock springs wouldn't get it done. I have a 351W ready-to-go, in my garage, but I don't want to make a car that is miserable to work on (My EFI Fox is bad enough), so I'll probably stick with the 302. It's going to be so nice not to worry about all the EFI sensors, etc.

Are the fuel lines in the II big enough? I assume I need an electric fuel pump.

It will be a bracket car. I assume that Summit will be a good source for parts. Are there any other specialty sites or retailers I should know about? I have lots of experience with Windsor family engines. I need Mustang II and C4 information from you guys. Any problem areas I should focus on when I look at the car one-more-time before buying?

Tell me about your white car. I cannot even discern what's on top of your engine -super charger??

SSM doesn't exist anymore, so good luck trying to find those traction bars. The same guy on ebay that makes the subframe connectors also makes tractions bars, but they are a slapper style bar, as opposed to how the SSMs were.

A 351W is a really nice setup in a II. It's no harder to work on than a 302. The exhaust becomes a challenge, but it's not too bad. Heck, I just extrude honed a set of stock II manifolds and used them on my 351 powered II years ago.

Fuel lines should be ok, but because of the age I'd replace them. No need for an electric pump, a nice performance mechanical should do fine. Doesn't sound like you are looking to build a 600hp motor anyway.

Our white car has a supercharged 5.4 Gen2 Lightning motor in ;).
 
Hi!,about the 8.8 rear,it`s not that bad,if you want to do a fast job,just swap the spring perch from the 8 inch to the 8.8...the axle tube is actually 3inch compared to 2.5 for the II (talking about a 74 rear) it must be the same for all the years,just enlarge it and weld them in place with the correct pinion angle.as far as the u bolt,you`ll need longer 3 inch ones and i wouldn`t re-use old ones anyway...the width is different,it`s an inch wider and it just corrects the ugly gap of the II .The wheels originaly are way too set back in the wheel opening... add some custom weld racing of just fox wheels and your all set! 5 bolt 4 bolt ...it`s up to you,posi units in 8 inch units are $$$ and not that many gears choices.The 8.8 is centered differently than the II diff and if you hear that it will give you bad vibrations,it`s bull sh%$/ Mine runs great with it, use a fox driveshaft with spicer joints and get your shaft balanced by a pro don`t assume it`s ok.I got a new unit from Jeg`s ,the ford motorsport alu drive shaft for the fox.Emergency cable fits right in ,you just need to relocate the bracket of the cable.And finally use a fox flexible line from the car to the diff.....That`s it! It seems like a lot of trouble but it`s actually very easy to do. :D
 

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Power Surge said:
SSM doesn't exist anymore, so good luck trying to find those traction bars. The same guy on ebay that makes the subframe connectors also makes tractions bars, but they are a slapper style bar, as opposed to how the SSMs were.

A 351W is a really nice setup in a II. It's no harder to work on than a 302. The exhaust becomes a challenge, but it's not too bad. Heck, I just extrude honed a set of stock II manifolds and used them on my 351 powered II years ago.

Fuel lines should be ok, but because of the age I'd replace them. No need for an electric pump, a nice performance mechanical should do fine. Doesn't sound like you are looking to build a 600hp motor anyway.

Our white car has a supercharged 5.4 Gen2 Lightning motor in ;).

How did your 351 car run? What was the combo?
 
stock50LX said:
How did your 351 car run? What was the combo?

Now you are making me have to think, was a long time ago. :)

It was a stock 77 351W from an LTD. I had the extrude honed II exhaust manifolds, with true dual exhaust. I put on an Edlebrock Performer intake with a Holley 650 carb. I am pretty sure it was a double pumper. I had a built C4 with a manual valve body. The car ran a best of 12.9 on slicks.

This was the car (motor out in this pic)..

351ghia.jpg
 
Power Surge said:
Now you are making me have to think, was a long time ago. :)

It was a stock 77 351W from an LTD. I had the extrude honed II exhaust manifolds, with true dual exhaust. I put on an Edlebrock Performer intake with a Holley 650 carb. I am pretty sure it was a double pumper. I had a built C4 with a manual valve body. The car ran a best of 12.9 on slicks.

This was the car (motor out in this pic)..

351ghia.jpg

You must have had a decent stall converter and some gears too. Were you running stock heads???? Those are terrible heads on a '77, 351.
 
stock50LX said:
You must have had a decent stall converter and some gears too. Were you running stock heads???? Those are terrible heads on a '77, 351.

Motor was as I pulled it from the LTD, aside from the carb and intake. Converter was stock II, but rebuilt. I think I was able to launch at close to 2k if I recall.

Nothing fancy, was just a hard running car with great hook. The thing left the light like no tommorow. The ETs were all in the 60fts.
 
stock50LX said:
Any problem areas I should focus on when I look at the car one-more-time before buying?


Can't believe no one has told you to check the floors for pin hole, or straight out, rust. Specially the passenger side if the car came with air conditioning.

These cars also rust in places you don't think they would rot.

The 8" is a good rear, overall. However I believe the II housing is weak, and sufferes other problems. The only reason I have a II 8" housing and related paraphernalia laying around here is someday I may want to return the car to stock. No rear I've installed was a direct bolt in.

I hear fitting a 351 is relatively easy if done by the torch and hammer method. I installed a W in one II, I didn't cut or beat under the hood. Either way it's not a drop in.

About Drop/ Bolt in pieces parts - You wouldn't be in the land of FoxStangs anymore. Aftermarkets scarce.
 
My II was a V6 car, so it had 5/16" fuel lines from the factory, I'm not sure if the V8 II came with larger 3/8" lines or not.
I upgraded to a summit 1/2" aluminum fuel line, and routed it exactly where the factory line was. The stock sending unit assembly also had 5/16" outlet, so I modified it with a section of 1/2" stainless tubing and brazed it into the factory unit. I wouldnt run the stock 5/16" fuel line with anything over 300hp.

My coupe weighed about 2700-2800 stock, though it's currently closer to 2500. (Just the bumpers/brackets weigh 85 pounds each) The big 17" Cobra R wheels and tires I recently installed added a lot of weight to my car, unfortunately.
You can easily make your car lighter with fiberglass doors(the stock doors weigh about 100 pounds each) install front and rear fiberglass bumpers, race seats(stock front seats weigh 38 pounds each, though the rear seat weighs almost nothing) And remove all the sound deadening material under the carpet. Install a fiberglass hood, but the stock trunk lid is very light already.
Use all available aluminum parts under the hood; radiator, water pump, heads, intake, etc. Get rid of the power steering and install a manual rack(that's another 35 pound reduction) And throw the battery in the trunk to help improve the car's balance.
The II is one of the lightest cars ever to be produced with a V8 engine, so once you learn their particular quirks, the cars are perfect for performance enhancements.
 
If you have $$$ Curry makes an alluminum case has a pretty good selection of ratios and is rumored to be in the prcess of making a 31 spline axle for the 8". They have more ratios listed than JEGS or Summit for reference.
 
What I would recomend for an 12-11 second Mustang II:

1.Have new rear springs made with an extra leaf. My car hooks really well with no axle hop now. (I actually scaped the rear bumper with the stock springs) :D

2.Frame connectors. (I modified the Comp engineering Pinto frame connectors). It would have been easier to make them from scatch!

3.You will need some kind locking rear axle. I have an inexpensive stock car mini spool. So-far so-good. I have never had rear axle issues in a II. The engine and transmission tend to blow-up first when playing weakest link :D

If you were looking to run faster then 11's or 12's I would change the rear-end to a race prepped 8.8 with c-clip eliminators and 31 spline axles. Or you could put in a trusty 9" Ford but, they are old school and there added strength is tarnished by increased rotating mass and friction.