• Welcome to For Trucks Only !

    We are a community of American Brand Pickup Truck and SUV owners. Join now! Its Free!

First project

jcord77

New Member
Joined
Jun 27, 2021
Messages
1
Reaction score
0
Location
alabama
Ok so I just bought my first project truck and it’s a 84 d150 with the /6 and a833 and I’m wanting to put a v8 in it I have a 5.9 magnum and I know where I can get a 383 or a 440 I want to cam whatever it is I end up with if it’s the big block probably a Hughes whiplash and the 360 probably a big mutha thumpr from comp anyway what all do I need for the swap (bellhousing clutch etc.
 

MoparsOnly

The snozberries taste like snozberries.
Joined
Sep 24, 2015
Messages
270
Reaction score
75
Location
South Carolina
you'll get better performance with a Lunati voodoo then any of the thumper cams. I'd be looking at front suspension since the weight of the magnum, BB or RB. Probably new crossmemeber.
 

vern14

Member
Joined
Nov 16, 2020
Messages
6
Reaction score
0
Location
Loxahatchee
Oil pan and pickup,transmission mount, shift linkage, throttle linkage, driveshaft, radiator. To name a few.
 

AJ.

Active Member
Joined
Mar 16, 2020
Messages
52
Reaction score
23
Location
manitoba Canada
Putting one of those cams in, works with an automatic, and a modest stall at least. But don't try it with the 3+1 Mopar A833.
Assuming that A833 is an overdrive box; the ratios are 3.09-1.67-1.00-.73od.
You will have very little torque from idle to about 1800rpm or a tad higher. If you have 235/75-15 tires and 3.23s, then 1800 does not occur until 16mph. With that super wide-ratio trans you will find yourself in that gutter in both second and third as well. And your cruise rpm will be, 65=1780 with the engine still in reversion, read; very poor fuel economy.. Those cams demand some rpm to get out of that reversion zone.
But a regular type big-cam has a similar problem. Again with a manual trans, the low-rpm will be soft. The only way around that is with more cylinder pressure.
I hate to rain on your parade, but that's just the way it is.

Install an automatic and at least a 2800 stall, and all this sorta goes away.
The Magnum is a good starter because it already has a tad more than 9/1 Compression ratio. but I still woudn't waste my time with one of those cams, unless all I wanted was the sound, with nothing to back it up.
The 383 is a hi-rpm engine not well suited to running this type of cam.
The 440 would seem to be the engine of choice, because they already have a lot of torque.
Finally, the overdrive gear in that box is fine for the slanty, but IMO, is rather weak for anything over a 318. I blew three of them up, all in the same summer, one with a lo-compression smoggerteen.

Now; if that A833 is a regular 2.66-1.92-1.40-1.00 box, then fine, carry on.
 
Last edited:

AJ.

Active Member
Joined
Mar 16, 2020
Messages
52
Reaction score
23
Location
manitoba Canada
Just to add;
IMO, the 5.9M is the engine I would chose, but, if you intend to stick with a manual trans, then;
because it has already a 9.2 or so Compression ratio, you are limited in how SMALL a cam you can run, before the high cylinder pressure runs you into detonation. And
You are limited in how BIG a cam you can run, before the bottom-end goes soft.
Actually, with the engine stock, there is a very specific small-range of intake valve closing angles, that will get you optimum pressure to run the grade of gas you choose. You can run less pressure. but running more can get you into trouble.
Assuming the 5.9M is at a true 9.2Scr, and that your local elevation is 500ft;
Your optimum pressures are about;
165 with 91 grade gas, 160 with 89 grade and 155 with 87.
to run 155, your Ica needs to be about 57*
to run 160, your Ica needs to be ~53*
to run 165, your Ica needs to be ~48*
As you can see, the later the intake valve closes, the lower goes the pressure
the Big Mutha Thumpr SBM has an Ica of ~72* way off the chart. and so the pressure is predicted to be 132psi; extremely low. Now remember, with a clutch, the tires are married to the engine; you cannot be at 2800 and zero mph unless you are slipping the clutch. That means a soft bottom-end is a big fat disappointment.
With that 3+1 transmission, you will have to rev First gear to 4400, to drop into Second at 2400, to find some torque to continue accelerating NORMALLY, never mind briskly. 4400 in First with 235/75-15s and 3.23s is 38mph. Can you see the problem there? Do you want to do that nearly every single time you take off in traffic?
Typically I shift my 367 at no more than 2800 when just tooling around. My manual trans has ratios of
3.09-1.92-1.40-1.00-.78od, and I have 3.55s with 27" tall tires; so 2800 in First is 20mph. On the shift into Second, the rpm drops to 1740. But my 367 has so much torque that if I mash the gas, the tires will spin. I built this combo to do that. The current cam has an Ica of 66*. The previous was 61* and it had even more low-end grunt. Neither of these cams has a noticible idle-lope at 700/750 rpm. These are small cams that make tremendous low-rpm torque, when coupled with optimum pressures, tremendous for a 360, lol.
To continue;
The operating range of the Big-M cam is listed as 2500 to 6200. The .050s of this cam are 243/257/107+5; no, 257* is not a typo; this is a very big cam. If it's your first time in this arena, I can tell you that it will NOT be an easy tune for you. The lifts are advertised at .568/.554 at 1.6 rocker ratio, so that will not even work on the stock heads.
There is not a snowball's chance in hell that I would run that Big Mutha in a 360, period. Not street/not race.
BTW
the pressure with an Ica of 72*, in a 9.2Scr/5.9Magnum, is predicted to be just 132psi as stated above. Car for car, at low rpms, this will feel like a lo-compression and tired, 273 2bbl. By 1800 it's picking up. By 2400 it should be out of reversion. The power might start around 4000 and peak around 5500, and with Magnum heads, your shift-rpm might be at around 5800, but you'll have to get your guides modified to run the lifts.
5800 in first with 3.23s and a 90.7" roll-out, is 50mph. In Second it is 92mph. And you'll never hit 5800 in Third/Direct on account of it's 154 mph.
So it should be obvious to you by now, that if nothing else, the 3.23s are ALL wrong. And so is the cam.

Ok so I can hear the gears in your head working; What is the right rear gear to run with that Big-M cam? Well it really doesn't matter because it's the combination that is all wrong. Starting with the 3+1 transmission. The gears are just too far apart for a hi-rpm cam. It doesn't matter what rear gear you run, THAT wide-ratio trans is still the biggest problem.
The ratios are 3.09-1.67-1.00-.73od. and
the splits are; .54.-60-.73, but you have to be gentle going into od else you will blow it up. What these numbers mean is that at the 1-2 shift, the Rs will fall to 54% of what you outshifted at. And at the 2-3 shift, the Rs will fall to 60%. This is not a big deal with a stock slanty because shifting at 3200 say, the Rs will fall to 1730 and 1920, and the slanty has enough power at those rpms because it is a low-rpm engine running a low-rpm camshaft.
Not so with a Big-M cam in a 5.9M
The point I'm leading up to is that, in the end, the Big-M camshaft will cost you a whole different transmission, and possibly a whole different rear end, and for sure an engine rebuild to a higher Scr; not to forget that the heads will have to be modified to accept the hi-lift specs.
IMO, I would leave that cam on the shelf.

Instead;
I would figure out what transmission and gears you currently have, what tires you want to run, and your budget; and then either select parts to work with what you have, or get a bigger budget.
 
Last edited:

MoparsOnly

The snozberries taste like snozberries.
Joined
Sep 24, 2015
Messages
270
Reaction score
75
Location
South Carolina
Well stated AJ. I'm In the midst of restoring my truck top to bottom. It's a 90 ram so It came with the roller cam and LA head. I ported the runners a decent amount and polished the chambers. I also swirl polished the valves and back cut them. They were cut .030 to tighten the chambers there at 66cc's. I figured I'll be about 10:1. I'll be running a Edelbrock AG. The cam I'll be running Is a Comp Cams Xtreme Energy™ 218/224 Retro-Fit Hydraulic Roller Cam for Chrysler 273-360. Street Machine. 3.23-3.91 gears, stock converter in 340 & 360, mild converter in 318, 9:1 Compression. The lift will be 535/531@ 1.5 or 6 doesn't have It listed. The rockers I have are 1.6. It has the power range 1400-5500 this Is where I need It since I'll be towing a camper most of the time. My gearing will be 3.55 and a tire that Is about 31-32. I've always found that Mopars respond well to 4 pattern cams. I usually stick with Lunati Voodoo series but this build called for something a little more tame. Mopars a different breed when It comes to building them up. I've been doing It since 16 and I'm 54. I learned a lot from trial and error. If you have the time and patience also a place to work you can back cut valves, swirl polish the back of the valve etc.. watch some video's like Uncle Tonys Garage. He's a great guy and really knows his shit. I know him personally from when I was growing up In NY. Lots of luck In your build and enjoy It.
 

AJ.

Active Member
Joined
Mar 16, 2020
Messages
52
Reaction score
23
Location
manitoba Canada
Comp Cams Xtreme Energy™ 218/224 Retro-Fit
In a 10/1 iron headed combo, that will, IMO, make, too much pressure to run pumpgas.
I hope that you have done your homework...
31.5 tires will change your effective gearing from 3.55 x24/27=3.155 with 27" tires to ;
3.55 x24/31.5= the equivalent of 2.70s, with 31.5s.
The difference being about 2.70/3.155= .856 or about 14%.
At 65 mph your rpm is looking like 2460@ zero-slip.
Depending on; the shape, size, and weight of the camper, your slip could be as high as 8 or even 10% .. Lets say it's just 5%; that would then tach at 2580. 8% would tach at 2660.
But while taking off, those 3.55s will feel like 2.70s, so you're gonna need a lot of cylinder pressure and/or a good amount of stall.

The problem is that the higher stall is gonna generate heat in slippage, and cost you mpg.
But
Your engine will make a lotta pressure. The Scr with flat top pistons yes may come in at 10.0 .. The Wallace calculator predicts 168psi at 350 ft elevation with an Ica of 60*. I have not heard of anybody on FABO, with the exception of @Yellowrose, who has run that on the street, with iron heads,
much less towing with the equivalent of 2.70 rear gears and at around 2600rpm. The 2600 might be doable, but you still gotta go thru the gears to get there.......
I mean if you can do it, I would applaud you as a pioneer. And I really want to see you succeed. But I myself am not that brave.
 
Last edited:

MoparsOnly

The snozberries taste like snozberries.
Joined
Sep 24, 2015
Messages
270
Reaction score
75
Location
South Carolina
First my ram Is 4 wheel drive. I was thinking 31-32 because that Is just about stock size. I will be using the stock rim so, I'm not setting everything In stone. The only thing that Is, Is the engine already done. The next thing Is that the tranny Is changing to a 47rh that will be rebuilt with a PATC level 3 kit which comes with a new TQ I'm leaving stock as far as stall. The diff's haven't been touched yet so I can change my R&P ratio. I live In SC by the beach so I'm pretty sure I'm at sea level. I don't care what anybody says when It comes calculator's. Not all engines are machined perfectly. Mine was machined at a local guy that doesn't do race car motors. Brand new my motor will have some blow by. I also know plenty of good ole country boys that run up In the 180's for daily drivers. I think to many people complicate this stuff. I say keep It simple shithead (meaning me). When I first got Into hotrods there was no such thing as the internet or calculator's of any kind. We picked our parts carefully and, let the chips fall where they may. Thanks for the info It Is appreciated.
 

AJ.

Active Member
Joined
Mar 16, 2020
Messages
52
Reaction score
23
Location
manitoba Canada
Excellent choice on the transmission; it should give you many years of trouble-free service. The .69 overdrive is enviable, and allows almost any rear gear to be used. For example; targeting 65=2200 in overdrive with 31.5s , allows a rear gear of 4.56s. That will liven up the take-off immensely, as the starter gear is now 4.56 x2.45=11.17, and will feel like 3.91s with a 27" tire.

When I first got Into hotrods there was no such thing as the internet or calculator's of any kind.
That may be, but 20years ago the general consensus was that 9.5 Scr was the highest we could run on the street, and I was told it was the same for alloy heads.
Butum; I did have a calculator and I knew a little trigonometry/geometry, so I figured out longhand in 1998/99 how calculate Dynamic Compression Ratios; which builders around here had never even heard of. So I built my 367LA to 11.3Scr for alloy heads, to run the Mopar 292/292/108 cam; targeting 8.5Dcr/185 psi. It came in at 8.6Dcr and 177 psi of cranking cylinder pressure at an elevation of 930 ft, and it ran full timing on 87E10, which I had not expected. ........... and was a pretty hot combo.
Had I listened to the local builders, and set it up at 9.5Scr, that engine would have been a complete dog at low-speed/low rpm, with way less performance below about 3000 rpm, than a tired lo-compression 318LA.
I eventually freshened that engine with a plasma-Moly, file-fit ring kit, and the LeakDown was so low I could hardly read it on my 2"- ish gauge. And I test at 80psi.

I get what you are saying,
but IMO, that's no way to recommend something to a novice for a first project,
and especially not for a use with a manual trans where the engine is married to the rear tires, with no convertor to help cover a poor choice of parts, and most especially not for street use where something like 95% of the engine's life will be spent below say 3500rpm. You cannot run around town slipping the clutch all the time; the engine has to make decent torque down there; and the more the better.
I use the Wallace Calculator because it works; and works well. It only asks for Seven inputs, so it's not real complicated.
 

MoparsOnly

The snozberries taste like snozberries.
Joined
Sep 24, 2015
Messages
270
Reaction score
75
Location
South Carolina
IMO, that's no way to recommend something to a novice for a first project,
I get It I was just using It as an example. I wasn't expecting jcord to use It as a blueprint.

I to use wallace for tire sizing and gear ratio stuff.

Well there were some sharp minds where I originated from and 10-10.5 comp ratio's where the limit of a street machine. Being on LI and having access to marine and aviation fuel pretty much everywhere made It easy to run that kind of set up. Guys would mix there own fuel. Then it would travel through all the circles. The premium mix got finalized to a 80/20. That Is 80 pump 20 aviation.

Today some of the good ole boys down have some homemade 190 proof and mix It In with 87 and It works like a charm. It makes for a really cheap high octane gas.
 
Top