Moparts

F or M body with big block?

Posted By: VincentVega

F or M body with big block? - 10/15/13 07:30 PM

Just curious if anyone here is running a big block in something like a Diplomat or Volare, with the stock suspension.

Does it become unsafe to drive with all that extra weight up front?
Posted By: Diplomat360

Re: F or M body with big block? - 10/15/13 08:38 PM

The weak link is the T-bar setup...but if you have the $$$ FirmFeel can set you up with a much stouter replacement piece...having talked to someone who's done this they were much impressed and he loves the new feel of the car.

Now...the real question: why big block? Why not stroker small block? lol...
Posted By: VincentVega

Re: F or M body with big block? - 10/15/13 08:50 PM

curiosity and money.

I know it'd make a good drag setup but that's not how we use our cars. have a volare duster that's in pretty good shape, basically just a rolling chassis with rebuild front end.

also have lots of BB stuff and a very low budget. Would be a nice way to get dad back into the game in his retirement years. but don't want it to be dangerous!

I have an aluminum slant six for my diplomat
Posted By: nomore65BelvJim

Re: F or M body with big block? - 10/15/13 09:20 PM

Either spend the money on the upgraded t-bars or spend it on aluminum everything for the BB to get the weight down closer to the SB weight.
Posted By: 80fbody

Re: F or M body with big block? - 10/15/13 09:48 PM

I say go for it. Will be a cool ride. I own an f body, 4speed car with approx 400hp smallblock. These cars are very stable & have a nice wide stance with a good wheel package. A few front end tweaks, an 8 1/4 posi rear & it will be a cool toy. First thing I'd do would be solid front bushings for the k-member, good kyb shocks, new tires & a good alignment.

The front bumpers & bumper shocks weigh a ton. Certainly a place to lighten up. I've done aluminum bumper brackets in the past.
Posted By: Supercuda

Re: F or M body with big block? - 10/15/13 10:00 PM

Oh good lord.

Yes you can run a BB in an F/J/M body with the stock suspension.
Posted By: racealittle

Re: F or M body with big block? - 10/16/13 12:15 AM

I ran a 440 in an'77 Volare RR for nearly 32 years and it was a blast. Would I recommend it for everyone? Not when you can build a stroker sb.

There were no issues with the front suspension. The rear did not hook until I put a superstock spring suspension under it. There are other choices available for that as well.
Posted By: 440PURSUIT

Re: F or M body with big block? - 10/16/13 03:31 AM

I have a dealer demo kind of loaded 59k 80 Dippy coupe i intend to put a magnum headed early 318 w A500. im wondering what my best rear option is. eliminate iso-ride?
Posted By: dynamite

Re: F or M body with big block? - 10/16/13 12:31 PM

I am running a stock K frame from a 5 th ave with stock t- bars in my 56 Plymouth ...I have am iron head 493 stroked 440 and have run it for 4 years now..I like everything about it...rides well on long trips . (When I change to the 2: 76 rear ).and runs well at 11.6 @ 115 mph .with 3:55 gear.the whole car weighs 3700 lbs.The only problem I had was the headers and the P/S box want to occupy the same space..but with a little heat and bending ,it works

Attached picture 7889424-002.JPG
Posted By: Anonymous

Re: F or M body with big block? - 10/16/13 04:59 PM

Quote:

Oh good lord.

Yes you can run a BB in an F/J/M body with the stock suspension.




I agree. Thats what this Mirada had in it, just a 10 second street car.

Attached picture 7889663-440mirada.jpg
Posted By: 70Cuda383

Re: F or M body with big block? - 10/16/13 05:10 PM

It's just a big block, not a cummins diesel!

Stock for stock a big block is what? 150? 200 lbs heavier than a small block? Aluminum heads, intake, water pump housing, water pump, headers... And that big block weighs the same as an all stock/iron small block.

The front end will be fine.
Posted By: a12rag

Re: F or M body with big block? - 10/16/13 07:23 PM

Have a buddy with a 79 t top Road Runner . . . 440 with 518 auto behind it, stock front suspension. Car works great - perfect for long trips, with the AOD in it !! . . . go for the BB build. You can always change out the T bars once you have seen what it drives like with the BB drive train in it . . .


Cheers,

Mark
Posted By: VincentVega

Re: F or M body with big block? - 10/16/13 07:35 PM

thanks for all the feedback.

and that sounds like a very nice setup, 440 with 518! how was it done? u ultrabell or adapter?
Posted By: Diplomat440

Re: F or M body with big block? - 10/16/13 09:31 PM

i have no issues with mine, handled just fine with an all iron 440.
Posted By: Diplomat360

Re: F or M body with big block? - 10/17/13 01:04 AM

I suppose a follow-up question could be: how well will it handle with the stock T-bars and 440 in there?

All the posters are absolutely right...it sure can be done...but will it handle, will it be a street car that you have to adjust to as you shift between your daily driver and your project car, or are we talking here 1/4 mile cars that go 'straight'????

Put it this way, my coupe is completely re-done, all new parts, including Koni 5-way adjustable shocks (front & rear). They are a day & night difference as compared to a stock or even HD shocks. Yet, there I am with a 360 block up-front (iron heads) and boy, that front-end likes to 'float'. Already have the replacement K-frame biscuits too.

So...I like a car that handles like it's on 'rails'...LOL...and a stock T-bar isn't going to get you moving in that direction!
Posted By: racealittle

Re: F or M body with big block? - 10/17/13 01:17 AM

I had a 1.25 front cop swaybar on the car, no rear swaybar. The dreaded KYB front shocks and cheapie long 25" Monroe Pickup truck shocks on the rear. It took corners pretty good, the ride was great. It was a rougher ride with the small block and KYB's on all 4 corners, (also had the cop rear bar at the time). It really did handle great as a small block, but big torque is more fun sometimes.
Posted By: Supercuda

Re: F or M body with big block? - 10/17/13 04:51 PM

Quote:


So...I like a car that handles like it's on 'rails'...LOL...and a stock T-bar isn't going to get you moving in that direction!




An M body isn't going to get you there either.
Posted By: VincentVega

Re: F or M body with big block? - 10/17/13 05:10 PM

yeah, I know what you mean about the float. My slant six M body with "cop" t-bars (as far as I know they just used higher durometer bushings) and the big swaybars handled very well. Firm suspension at any speed, even at 85 and beyond. however my 79 318 lebaron rode like a cadillac. Not exactly inspiring to drive

I could imagine stepping up once more would make it a bit on the scary side. I like to at least have the ability for evasive maneuvers.

I think I've gotten the impression I need here. thanks for all the information
Posted By: a12rag

Re: F or M body with big block? - 10/17/13 06:46 PM

Quote:

thanks for all the feedback.

and that sounds like a very nice setup, 440 with 518! how was it done? u ultrabell or adapter?




Pretty sure he used an adapter. He has diventa lots of hiway miles on it, and never heard him complain about the handling.

Don't think you are gonna get a canyon carver without heavy $$$$ investment. Am sure it will be acceptable with stock tbars and BB drivetrain.
Posted By: nomore65BelvJim

Re: F or M body with big block? - 10/17/13 09:19 PM

Quote:

Have a buddy with a 79 t top Road Runner . . . 440 with 518 auto behind it, stock front suspension. Car works great - perfect for long trips, with the AOD in it !! . . . go for the BB build. You can always change out the T bars once you have seen what it drives like with the BB drive train in it . . .


Cheers,

Mark




Good point. Its only 4 bolts for each bar, pretty simple swap

Edit: 5 bolts each side...forgot the sway bar end link
Posted By: MarkZ

Re: F or M body with big block? - 10/18/13 02:30 AM

Quote:

Quote:


So...I like a car that handles like it's on 'rails'...LOL...and a stock T-bar isn't going to get you moving in that direction!




An M body isn't going to get you there either.




Why not? You're talking about a platform that weighs similar to that of a B body and has almost the exact same offerings available to it in aftermarket suspension parts. There isn't a part you can't replace now. FF offers big T-bars, sway bars, tubular UCA, etc, etc. Hell, you can even get an Alter-K that will bolt under these things.
Posted By: MarkZ

Re: F or M body with big block? - 10/18/13 02:52 AM

Quote:

I have a dealer demo kind of loaded 59k 80 Dippy coupe i intend to put a magnum headed early 318 w A500. im wondering what my best rear option is. eliminate iso-ride?




Find a fleet model (cop car) and grab the 8.25" rear axle. You can nab the rear sway bar while you are there too. The axles came in two ratios: 2.24 and 2.94. I would stay away from the numerical lower of the two since you need to change the carrier if you want to higher.

Depending on if you want to ditch the ISO setup will determine how the sway bar will attach. The factory method has the end-links mounting to the shock plates. If you replace the plates with B body ones you'll need adapters from Firm Feel.

I ran with the ISO setup for a number of years and finally ditched it a couple seasons ago. It made a pretty noticeable difference with brand new five leaf springs and Edelbrock IAS shocks. I would certainly do it again.
Posted By: Diplomat360

Re: F or M body with big block? - 10/18/13 03:46 AM

Quote:

Quote:


So...I like a car that handles like it's on 'rails'...LOL...and a stock T-bar isn't going to get you moving in that direction!




An M body isn't going to get you there either.




Granted, it would take some good $$$ to make and M-body handle like a modern car...but as Mark pointed out...it's no different for M-body or B-body.

If you like good road manners it's a worthy goal to have. Consider the changes you make to the car, match the parts up correctly and enjoy the results!
Posted By: TC@HP2

Re: F or M body with big block? - 10/18/13 04:18 AM

Quote:

I suppose a follow-up question could be: how well will it handle with the stock T-bars and 440 in there?






It'll handle like a big block A body. They are spendy, but Firm Feel does offer bigger t-bars for the FJM cars.
Posted By: Commando1

Re: F or M body with big block? - 10/18/13 01:39 PM

Quote:

Why not stroker small block? lol...



Because that is just what it is. A small block.
back atcha...
Posted By: buildanother

Re: F or M body with big block? - 10/18/13 05:42 PM

Little off topic, but any input on the header fitment on these "B" engine cars?
Posted By: racealittle

Re: F or M body with big block? - 10/19/13 09:58 PM

Quote:

Little off topic, but any input on the header fitment on these "B" engine cars?




TTI do a fine job with a big block. Very easy Install. The header can easily fall to the ground during installation if you lose your grip on the passenger side. The driver side needs to be jacked up to just about fall into place..
Posted By: Remow2112

Re: F or M body with big block? - 10/20/13 05:11 AM

Been running one for years. Prefer the 383 / 400 B over the RB. If you have an AC car with the bulge on the passenger side firewall it is real tight with a RB block.

This is my write up and parts for a BB Fbody install using stock motor mounts. I have since switched to Schumacher conversion which works great too.

Here is the deal. I did this for a mostly drag race car.
1. I have manual steering (Don't know if PS will clear.)
2. Used factory late model BB spool motor mounts.
3. The tranny mount (not the cross member) needs a little modifications.
4. Hedman Hedders 78030 work great in a Volare.
5. I put in a cheap 26" aluminum radiator with the upper and lower ports matching a BB.
6. Milodon 30931 oil pan
7. I am using manual brakes. You can stick with PB but you will need to find a different power booster that will clear the valve cover. An A-body one might work.

Details:
Using the stock motor mounts will put the engine about a 1/2 further forward then using the Schumacher conversion mounts and a little taller. What I did was got a set of beat BB motor mounts and drilled some 1/4" holes through the rubber on the engine side of each mount. (They sit just a little wide and you need some extra give. I also trimmed the extra rubber and metal off the front and back of the motor mounts making them flush to the spool insert front and back. If you don't do that when you get it in the K frame mounts it tweaks the engine so it sits crooked in the engine bay. You will need to buy a bunch of flat washer and cut slots out of the bottom. When you trim the spool ends it leaves a gap on the K-frame mount and you have to fill the gap before you tighten down or you will never get them tight. I did that with cheap washers.

The only mod I did on my K frame was on the passenger side at the front of the motor mount. There is a long thin v fin towards the front of the car. I took a grinder and cut it off because the engine block hits it.


The tranny mount has 2 slots. You need to cut them open on the end that goes to the front of the car. You will then be able to have enough adjustment to get it connected to the 727 tranny. If you weld you can extend the slots.

I used the headers listed above. There are 2 styles of BB headers (that I have seen) this version will not work, Hooker Headers 5209HKR. It has the 5 tube cross over and the 7 sticks out. The 7 will not clearing the steering.

You cannot use a small starter or modern starter. It will hit the header tube. They sell expensive indexable style starters that will work. I just bought a old style 440 starter (It has a longer motor and a little more torque) For those that will ask. I did try banging some clearance in a headers tube to fit the small style starter. I got the tube to half the original diameter and gave up. Not worth it to loose that much flow in 1 tube. I have not had an issue with heat saturation yet.

For a drive shaft I went and found one out of a 70 station wagon and had it shortened. I would not recommend using the small diameter drive shaft. I have a mild 400 and it feels radically different launch then my 375hp 360.

I also chose to cut part of the fender well out on the passenger side to make it easier to get to the #6 spark plug. All the rest are easy. If you don't want to go that route you can drill a 1.5" hole in front of the #6 and get to it that way. The plug wire will still be a pain.

Oil pans: I started with a 699 (this is a number stamped in to the bottom of the pan ... Follow this link for an oil pan breakdown: http://www.440source.com/oilpans.htm) But the one I had did not have any baffles. After talking to a friend that has been racing BB Mopar for 20 years I switched to the Milodon listed above. He said that with a good launch and no baffles ( i am not exactly clear on what he considers a good launch His cars runs in the mid 10's.) you will starve the bottom bearings. He then warned me that it could still be done with a baffled stock oil pan so I chickened out and ponied up some cash. Back to oil pan options.

Mopar pans 699, 971, and 187 should fit fine. 971 is best just due to the extra room from the front of the pan to where the sump starts and you can still buy one from Mopar 5007807.
These are all 5 quart pans and if you are just street driving. I would just find a used stock pan and go for it. Most generic aftermarket oil pans are elongated 187 pans. Using a 187 or 699 might require a little trimming on the lip on the back of the k frame where the sump sits.

Do not try to put the engine and tranny in together. The engine hits the firewall and prevents the oil pans from clearing the k frame. I tried!

I also chained down the driver side of the engine since I beat up on the motor mounts quite a bit.

There is no reason that this could not be done with a 440 but the extra 1/2" a side is going to make the passenger side even tighter fit.

If you have your act together there is not reason that you couldn't put a BB in your F or a normal weekend. But they will be long days.

Dan...
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