This is just a general performance question. I am wondering what performance upgrade i could get for the best bang for my buck. As some of you guys know i have a 72 charger 440 with the good old 727. As the car sits right now it has most of your basic bolt on stuff: it has the performer rpm intake, 800+ cfm Holley double pumper, Pertronix electronic ignition, headman long tubes and 2.5 inch exhaust w/ Flowtech afterburners. The heads and cam are stock 68 Magnum stuff. I have the open diff that came with the 318 from the factory and it is obviously geared pretty wide. i am also running 15x10 steel craigers in the rear with tiger paw gts radials on it. The ugrades i had in mind are one of the following; a small shot of nitrous (100-125 hp.), Welding or replacing the rear diff (but it has to remain street-able) , Cam (although it seams like i have to pull the motor which will be horrid with the headers.), Basic cylinder head work, Or a set of street legal drag radials and aluminum wheels (perhaps w/ the new or welded diff.) I am also open to other suggestions but whatever i choose to do i want to keep it cheap. Any good opinions? any help would be great.

 

Heads, you want something to run better it has to breathe. My 2 cents

 

Tang, Not trying to be a smarta$$ at all but your last sentence says a lot.. "It has to be cheap". My personal experience is that cheap and speed do NOT go together... In raicng we have a saying... "How fast can you afford to go?" This is a VERY true statement in street cars as wellas full race cars......

 

If you want a "seat of the pants" improvement, swap to a lower gear rear. This will not help the quarter mile times (significantly) but it will make the car jump like a frog off the line.

 

gears and a sure grip/limited slip/posi in the rear axle. That is what I would do.

You could also pull the trans and install a 2000-2200RPM stall convertor inplace of your torque convertor and a shift kit, that will really help the car start moving in the RPM range that your motor starts to make some power.

 

Cheap is a relative term. I just mean im not looking for anything exotic. Im willing to spend money to do what i need to do right but im also not looking to spend $1800 bucks on bada$$ heads or anything. Maybe get the stock heads worked over or maybe a set of those 440 source heads. Im very aware that everything costs money. I may only be 21 but i am also completely independent financially.... I know im not building a 10 sec charger, i cant even if i wanted to. But any of the upgrades i am looking into are an improvement and they all are in my opinion "cheap." Just wondering which might help the most, or if there are any others i should consider.

The tranny and stall are a good idea too... any other thoughts?
Thanks guys

 

tang -

What M said. Almost anything you do to increase performance will cut down, sometimes drastically cut down on gas mileage - and that includes taller gears. That's not a problem with a race or show car, but for a daily driver - it can and will add up pretty quickly.

Re: the cam, no you don't have to pull the motor, but you will have to pull the radiator. The trick to an "efficient" set up is to have most of the "stuff" have the same rpm power band.

78D200 -

Do you know what the stall is on a stock torque converter? I have a 3000 rpm in mine and never played with a stock one in the Charger. Tks.

Crazy -

Why won't it help quarter mile times? Assuming, of course, you are not leaving more rubber on the launch and not leaving your rpm power band before going through the traps???

I haven't raced in 20 years, but with highway gears (3.23) I was going through the traps in the low 5000 rpm range with an assumed 6000 redline. Gotta think hitting the traps just before redline has to help???

Not suggesting going from a 2.73 to a 4.88, but calculating the optimal gear ration should help. Tks

Archer

 

Stock stall ratings are usually under 1200 RPM.

 

78 -

OUCH ...

Thanks

Archer

 

When you let your foot off the brake and the vehicle is idling in drive, your vehicle should be moving and that is around what RPM. 600-1200. A lot, if not all, vehicles are like that.

 

For improved "light to light" performance, I would agree with lower rear end gears and posi so you won't have a "one tire fire". Tomorrow, I am raising my gear ratio from 3:91 to 3:55. 3:91 with a 4 speed and a 440 is not a good combination for the freeway. At 70mph on the freeway with 3:91 gears and an A833, the rpm was very close to 4000 If you are just going to bomb aroiund town, 3:91 or lower might be a good choice.

 

Tim -

Here's how I was looking at it. The impeller(s) from the drive (engine) will always be trying to turn the one connected to the trany. The "stall" or lock-up is when the force of the drive impeller has to move it partner or slave, or the car stalls. That's why when idling at 800, and I get off the brake the car does roll forward, but still has slip until the stall speed is reached.

I think that would happen with a 1200 or 4500 stall converter, just at different rates.

Archer

 

Archer - You are correct, it is just stock torque convertors have a lower stall rating. It also depends on when your motor starts to make power/torque. If it is in teh mid to high range, then having a 3000RPM stall convertor is great.

 

Tim -

When we first built the engine (1982 ...) we tried to match everything (cam, intake, headers, TQ converter to "kick-in" around 2500 to 3000 rpm. Think we came close, but who knows, still fun to drive ...

Thanks

Archer

 

That is the right way to do it.

Anyways, back to tang72's topic.

 

Tang, I dont think you have to pull the motor to get to the cam. At least, on mine you dont.

 

i thought they were more like 1500

 

Yea gas millage is not a huge concern because i only drive it about 2k miles a year. I use my girlfriends car any time i have to go somewhere further than a few miles. i work about a mile away from my house and live 15 min from campus for school... i mean im driving a 440 around town and with my foot... i dont think it will get much worse. I just dont want something that is a huge pain to drive those short distances. I was thinking 3.55s or 3.73s for my car to get some pep in it. i can get a good used nitrous kit (100 shot.) for a couple hindered and at least that would be there when i want it and not bother me when i dont. i really want to focus on getting this body work done and paint soon but i want one last go fast goodie before i do because once i jump into body and paint i cant see me coming back to the motor for a while. I also really like the idea of a cam especially knowing that all i have to do is pull the radiator and not the whole motor... any suggestions on a cam? I have been looking at a few Mopar performance purple cams. I dont want anything super radical but a little thump is great. The three i looked at are 1. 284/284duration , .484/.484 lift, 2. 272/272 duration, .455/.455 lift, or 280/280 duration, .474/.474 lift but i have never picked a cam before.

 

Comp cams Camquest program. You can plug in all your stuff and play with alot of what-if stuff. http://www.compcams.com/camquest/

 

I'm not sure about the cool vehicles back in the day but vehicles no a days (90's to no) have a lower rating than that. A lot of the vehicles start to make power (if that is what the manufactures call power) early in the RPM range, not like most of the people on here who have built motors.