Another Rear End Set Up Question/Advise

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Now the issue of vacuum has come up. Does anyone know, or had problems with vacuum for the power brakes after a big block swap.
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It isn't an issue which is particular to big blocks. It's about the cam needed to achieve 550 hp from 460 Cubic inches. If the assumption in my previous post about your cam is correct, you will probably need a vacuum can to run power brakes. Rhodes lifters might be another option to explore but again, without specifics I am just guessing.

 
I was wondering about the "twist" from a convertible so I will look into the sub frame connectors. May do the springs anyway while we are in there. Will look at traction bars as well. Thanks for the suggestions.
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Aside from what I mentioned earlier about the "package" working together, I will recommend subframe connectors for ANY engine in any Mustang.

Even the non-ragtop cars are more flexible than you'd imagine.

When I tied my '90 Fox body convertible with subframes and front strut tower brace, the difference was absolutely night and day. And that car has a stock drivetrain.

Welcome to the Mustang "cash fuse"... it'll keep burning and burning if you let it... LOL!
Click to expand...
Ordered subframe connectors today from Global West! Will weld them in as soon as it warms up a bit.


Here is my set up based on jbojo setup. Any thoughts?

* Rear Gear Ratio = 3.50

* Rear Tire Size = 26.2" dia

* Overall Weight of the Car = 3000lbs???

* Engine’s Cam Specs: Lift, Duration and Centerline = .560/.560 lift, 292* duration, 244/244* @.50 and 106* lobe center.

* Cubic Inches of Engine = 460 bored .030 over=466ci

* Operating RPM Range of the cam = 2500 to 6500 rpm (in operating band on the freeway)

* I am estimating low 500 hp with my setup but I don't have actual numbers.

* Stall speed 3000

* C6 tranny

* RPM @ 70 is 3142


 
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I was wondering about the "twist" from a convertible so I will look into the sub frame connectors. May do the springs anyway while we are in there. Will look at traction bars as well. Thanks for the suggestions.
Click to expand...
Aside from what I mentioned earlier about the "package" working together, I will recommend subframe connectors for ANY engine in any Mustang.

Even the non-ragtop cars are more flexible than you'd imagine.

When I tied my '90 Fox body convertible with subframes and front strut tower brace, the difference was absolutely night and day. And that car has a stock drivetrain.

Welcome to the Mustang "cash fuse"... it'll keep burning and burning if you let it... LOL!
Click to expand...
Ordered subframe connectors today from Global West! Will weld them in as soon as it warms up a bit.


Here is my set up based on jbojo setup. Any thoughts?

* Rear Gear Ratio = 3.50

* Rear Tire Size = 26.2" dia

* Overall Weight of the Car = 3000lbs???

* Engine’s Cam Specs: Lift, Duration and Centerline = .560/.560 lift, 292* duration, 244/244* @.50 and 106* lobe center.

* Cubic Inches of Engine = 460 bored .030 over=466ci

* Operating RPM Range of the cam = 2500 to 6500 rpm (in operating band on the freeway)

* I am estimating low 500 hp with my setup but I don't have actual numbers.

* Stall speed 3000

* C6 tranny

* RPM @ 70 is 3142
Click to expand...
Actually finally decided on my rear end gears. Going with Richmond 3.70, Traction-Loc in a standard case. (have a WAR case but not sure if its better or not, anyone know??) 28 spline in a Ford 9"

Haven't pulled the trigger on a lot of stuff, like the carburetor and torque converter and ANY info or recommendations will be appreciated! Also ordered the sub-frame connectors from Global West and they are in process at the powder coaters!

 
Here is my basic set up based on jbojo setup. Any thoughts?

* Rear Gear Ratio = 3.50

* Rear Tire Size = 26.2" dia

* Overall Weight of the Car = 3000lbs???

* Engine’s Cam Specs: Lift, Duration and Centerline = .560/.560 lift, 292* duration, 244/244* @.50 and 106* lobe center.

* Cubic Inches of Engine = 460 bored .030 over=466ci

* Operating RPM Range of the cam = 2500 to 6500 rpm (in operating band on the freeway)

* I am estimating low 500 hp with my setup but I don't have actual numbers.

* Stall speed 3000

* C6 tranny

* RPM @ 70 is 3142

Actually finally decided on my rear end gears. Going with Richmond 3.70, Traction-Loc in a standard case. (have a WAR case but not sure if its better or not, anyone know??) 28 spline in a Ford 9"

Haven't pulled the trigger on a lot of stuff, like the carburetor and torque converter and ANY info or recommendations will be appreciated! Also ordered the sub-frame connectors from Global West and they are in process at the powder coaters!
Click to expand...
not enough info to pin a carb size down but it better be at least a 750 and more like a 780 - 850.

if you need a choke, i would buy a quick fuel ss style carb .

3000 stall will work but it will suck in stop and go traffic . . you can call tci or b and m for a part number that will work.

3.70 is WAY better than 3.50 but an overdrive would be nice if you drive 70 mph often.

.

 
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Here is my basic set up based on jbojo setup. Any thoughts?

* Rear Gear Ratio = 3.50

* Rear Tire Size = 26.2" dia

* Overall Weight of the Car = 3000lbs???

* Engine’s Cam Specs: Lift, Duration and Centerline = .560/.560 lift, 292* duration, 244/244* @.50 and 106* lobe center.

* Cubic Inches of Engine = 460 bored .030 over=466ci

* Operating RPM Range of the cam = 2500 to 6500 rpm (in operating band on the freeway)

* I am estimating low 500 hp with my setup but I don't have actual numbers.

* Stall speed 3000

* C6 tranny

* RPM @ 70 is 3142

Actually finally decided on my rear end gears. Going with Richmond 3.70, Traction-Loc in a standard case. (have a WAR case but not sure if its better or not, anyone know??) 28 spline in a Ford 9"

Haven't pulled the trigger on a lot of stuff, like the carburetor and torque converter and ANY info or recommendations will be appreciated! Also ordered the sub-frame connectors from Global West and they are in process at the powder coaters!
Click to expand...
not enough info to pin a carb size down but it better be at least a 750 and more like a 780 - 850.

if you need a choke, i would buy a quick fuel ss style carb .

3000 stall will work but it will suck in stop and go traffic . . you can call tci or b and m for a part number that will work.

3.70 is WAY better than 3.50 but an overdrive would be nice if you drive 70 mph often.

.
Click to expand...
+1

At 70 with those gears you would turn around 3324 rpm so with freeway driving mpg would be bad as well as driving comfort. With OD rpm will be around 2593 for a GV set up or 2260 with AOD. If little freeway driving then you could live with that.

Cam will have some lope to it. I believe that in big block it won't be as pronounced as with a small block. Carb minimum would be a 750, the TB I am using flows up to 970cfm. I used Rhodes lifters to help with vacuum so that may be a consideration for you.

As for stall I think that 2800 is what you would want but I would talk to TCI about it.

 
Whats a 3000 stall vs 2800 stall affect on driving? I mostly am going to be cruising locally with a little highway driving. Someone suggested a shift kit. What does that do for me? Thanks for all the help.
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the converter will be fully locked up at less than the stall speed under steady throttle but if you are cruising at 2000 rpm and step on the gas to pass someone etc, it will rev to the stall speed before it accelerates . . the higher the stall, the sooner it goes into neutral after you let off the gas.

 
If you haven't purchased the cam yet (and frankly even if you have) I would urge you to reconsider your choice.

Its going to sound great at idle but it is going to be miserable to drive on the street.

Does the car have power brakes?

 
If you haven't purchased the cam yet (and frankly even if you have) I would urge you to reconsider your choice.

Its going to sound great at idle but it is going to be miserable to drive on the street.

Does the car have power brakes?
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Yes, I have power brakes. The shop building my engine is not going to change the cam, said he has used this cam (and its similar grind) on many applications and his reputation is on the line-even though its my money.

What can I expect when driving on the street?


Another thing...right now I have an Edelbrock RPM Air Gap Intake Manifold. I want to run the standard hood, non NASA style. Concerned about clearance issues. What should I expect? Also, what headers should I look at to pair with my Trick Flow heads?

 
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If you haven't purchased the cam yet (and frankly even if you have) I would urge you to reconsider your choice.

Its going to sound great at idle but it is going to be miserable to drive on the street.

Does the car have power brakes?
Click to expand...
Yes, I have power brakes. The shop building my engine is not going to change the cam, said he has used this cam (and its similar grind) on many applications and his reputation is on the line-even though its my money.

What can I expect when driving on the street?


Another thing...right now I have an Edelbrock RPM Air Gap Intake Manifold. I want to run the standard hood, non NASA style. Concerned about clearance issues. What should I expect? Also, what headers should I look at to pair with my Trick Flow heads?
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The air gap will not fit under a standard hood without a hood scoop. I know this because an RPM wouldn't fit and it is shorter than the air gap I believe. A regular performer will fit but it is not the appropriate choice for your combo. The only manifold that will work with a standard hood and be somewhat of a match to your combo is an Eddy Torquer II. It is a small runner low rise single plane. The cobra guys often run this manifold due to hood clearance constraints.

I don't think the 292H cam will make enough vacuum to run power brakes.

The cam will idle roughly and be soft on the bottom end. It will scream above 4000 rpm or so though. I don't think you will want to use anything less than the recommended 3000 rpm stall converter. If you are committed to this combo then I recommend you get a custom torque converter from a reputable converter manufacturer. IMO the converter will make or break the street driving experience with this cam. The 3.70 gear sounds good.

The Q 850 you mentioned earlier in this post isn't a bad choice for a carb.

Not trying to rain on your parade. It just seemed to me that your build and how I perceived you intended to use the car were a little at odds.

I would certainly encourage you to listen to your builder if he has experience with BBF's.

Post a burnout video when its up and running.:D

 
RE: transmission and rear end question

Hey everyone, I was looking for some advise on my new set up I have planned for my 73. The new motor is at the machine shop and will be a 466ci with 550 hp and

545ft/lbs of torque at 4800 rpm.

I found a 9" rear end that is about 3/4" shorter width than my stock 8" rear. I assume the 3/8" (each side) difference wont matter and allow me to tuck some wider/bigger tires underneath. The Third Member has 2.69 gears. Looks like it will be a smooth ride on the highway, but allow me to light em up from a stop if I feel like it. Problem is the gears are open and not posi. I am spending so much on the motor...I need to keep the costs down a little on the drivetrain.

ANY info will help...thanks in advance. I look forward to hearing from you!
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Don't get hung up looking for the 9" Traction Loc in just a Mustang or Cougar. The center section is same in most of the F-150 pick ups and E100 vans. Go to a decoder site and get the decode info for what to look for. Take your binoculars and flash light and go junk yard and crusher yard hunting. It is easier to see the tag on the rear without crawling under if it is not covered in grease. You will need a different drive shaft due to larger U-joint from 8 to 9". Print up what you are looking for and take to the crusher yard. Here they will let you get stuff off before the smash them at great prices. I have seen N cases in 6 cylinder vans before.

David

 
This is all great help!!

Found a traction Loc complete third member from a 76 Lincoln. Should be in good shape. The car only had 33,000 miles. Received my Richmond 3.70 gears and will be swapping them out soon.

I looked at the Torker II and it is quite a bit shorter than the RPM-Air-Gap. Looks like I will be doing an exchange at Summit! Any thoughts on headers?

 
This is all great help!!

Found a traction Loc complete third member from a 76 Lincoln. Should be in good shape. The car only had 33,000 miles. Received my Richmond 3.70 gears and will be swapping them out soon.

I looked at the Torker II and it is quite a bit shorter than the RPM-Air-Gap. Looks like I will be doing an exchange at Summit! Any thoughts on headers?
Click to expand...
For your build the Hooker Super Comps with 2" primaries would work well.

Edit: The TFS heads have a raised exhaust port and utilize a CJ flange. I am not sure how the super comps will fit with the raised exhaust port.

You might consider PM'ing BT (member Cobra3073) He will be running the same heads and perhaps he will have some insight on header fitment.

 
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Thanks! Decided to stay with the air gap. I have an extra hood to play with. Anyone have hood scoop recommendations? Cowl induction mihht be cool, i also like the,wide and low scoop from the 70 Stang.

Any thoughts?
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not sure what you are looking to do . . you could modify a boss 429 scoop or 69 - 70 mach 1 scoop to fit.

do you want a weld on scoop?

71 - 73 factory cougar scoop copy

http://www2.cougarpartscatalog.com/71gtscoop.html

ring brothers scoop

http://ringbrothers.com/body-kits/ford-australia/falcon/1967-1971-falcon/universal-carbon-fiber-hood-scoop.html

a mach 1 hood will give you around 1" more clearance.

http://www.mustangandfords.com/featured-vehicles/mump-1101-ford-1971-mustang-429-cj/






.

 
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I was wondering about the "twist" from a convertible so I will look into the sub frame connectors. May do the springs anyway while we are in there. Will look at traction bars as well. Thanks for the suggestions.
Click to expand...
your current springs are useless because they are for a 302 engine so i would definitely change them . . unless you want a pretty stiff ride, i would not run front springs stiffer than around 400 - 500 lbs . . the ones below are 418 . . call to see if they are lowering springs which is what i would use.

https://www.npdlink.com/store/?p=catalog&mode=newsearch&search_str=coil+springs%2C+front&parent=1&year=1971

i would also run stiffer rear springs around 135 lbs if you want just a moderate increase in firmness.

look at caltracks bars if you don't buy anti wrap springs.

yes you need sub frame connectors and an export brace and rallye bar.

i would also run global west or maier racing strut rod bushings and a 7/8 - 15/16 sway bar with urethane bushings.

kyb gas adjust shocks or maier racing bilsteins.

small diameter rear sway bar.


.

.

Yes, I have power brakes. The shop building my engine is not going to change the cam, said he has used this cam (and its similar grind) on many applications and his reputation is on the line-even though its my money.

What can I expect when driving on the street?
Click to expand...
combined with your gears and torque converter, it will feel like a slipping clutch until it gets rolling and will start to run strong around 2800 rpm.

that comp 292h cam will probably have around 14 hg of vacuum so you will likely need an auxiliary vacuum can if you drive in traffic.

are those A460 heads?

if so why don't you run the A460 intake?

also, that is not a good cam for those heads at all, plus the lsa is 110, not 106 which is ok . . it has 72 degrees of overlap.

this cam will get you over 500 hp and 500 tq and will have a milder idle with more vacuum than your cam . . it will have .609 lift with 1.72 rockers . . i would get it ground on a 112.5 lsa for an 460 eng . . it will cost around $60.00 extra to do that . . the overlap at 112.5 lsa is a moderate 68 degrees.

http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=1068&sb=0

this is also a very good cam for your app imo . . if you want stupid hp just get the next size up comp or lunati in the same model

https://www.lunatipower.com/Product.aspx?id=3198&gid=289

heres a dyno of a moderately built 390 stroked to 445 from survival motorsports . . 450 hp, 500 tq.

http://fefordtech.com/index.php?topic=29.0

IGNITION - I would also run an msd box and msd anti vibration coil and set your plug gap to around .045"

.

 
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Thanks!! Great help. I want my builder to look at a roller cam and rockers. Dont want to wish i did it in the first place. I have the subframe connectors on the way. I will look into the other suspension parts. I figured I needed traction bars.

Any info or suggestions on hood scoops, for some reason, I want to run the standard hood and will need to cut my hood for clearance using the RPM Air Gap. Don't want it to look too obnoxious.

 
Thanks!! Great help. I want my builder to look at a roller cam and rockers. Dont want to wish i did it in the first place. I have the subframe connectors on the way. I will look into the other suspension parts. I figured I needed traction bars.

Any info or suggestions on hood scoops, for some reason, I want to run the standard hood and will need to cut my hood for clearance using the RPM Air Gap. Don't want it to look too obnoxious.
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i posted a few links to some scoops.

i'm familiar with the cams i posted and the one he posted especially since i am also a comp cams dealer.

it would help a little to know more specifically what you are looking for like:

tire burner or tire warmer?

low end power or 7,000 rpm screamer with no low end power?

lite to lite drag car or freeway flier or inbetween.

mild, moderate or obnoxious idle?

what exactly did he say the comp cam would do?

EXACTLY which trick flow heads do you have?

 
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