72MachOne99GT

I posted this is classifieds earlier this week by mistake, I was wondering why I only had one post in reply.. *facepalm*


I don't frequent this part of the forums very often as I spend all my time messing with my '99 and cursing my dad for leaving the '72 sitting in the garage ALL the time almost.

I've tried to convince him this year to finally ditch the stock exhaust on the car, and the monstrous mufflers that are obviously choking the sound.

I'm a bit more interested however in knowing what it would take to wake the car up.

It's an automatic '72 Mach with the Q Code 351-4v.

I've heard enough people talk about heads/cam swap on OHV motors doing wonders, and being much simpler than the head swap was on my '99GT.

What do you guys recommend for a car that's never going to be a strip car, but needs some motor work to make it a good bit quicker on the street?

I'm sure I could handle MOST of the labor with the help of my dad or some friends.

Silverblade

my friends boss (local performance dyno tuning shop) speaks down on edelbrock "from experience" while many people on here are quite happy with the results. I am a bit of a newbie myself, but from what i have read the most important thing is flow matching your parts. You need a head cam and intake that all work together with one another.

Edelbrock is just an example. AFR and trickflow make good heads as well, not sure which intakes match up with which heads (AFR 185s for example), and then you can get a cam custom ground to match flow numbers.

Not too much help, but a good way to subscribe as I am interested as well for the 351W i have sitting here.

bump.

1971mach1

What rear end gears do you have? It should be a code on the door data plate.
I bet you have highway gears. Higher numerical gears like 3.55 would wake up that car alot, give it alot more torque (which is what you want for the street).
The stock 4v heads already flow good. A better flowing exhaust would
help alot.
A new Edelbrock carb really helped mine too, better drivability and more power.

67mustang302

Port tongues, intake, exhaust and a hyd roller cam, along with a general rebuild and all the other necessary crap. That way you can reuse the heads you have, but clean them up and make them perform better, but for less money than buying new heads.

THUMPIN455

Dont need to touch the ports, dont need to change the intake. You can swap the cam, springs, and rocker arms add some headers and it will wake up just fine. A cam like the Comp Cams 270H or 280H works well for plenty of bottom end and midrange power. I had the 270H in a 4V some time ago and it would roast the 3.00 gears for a block off idle. The rest of it was stock, they dont need much changed to run a lot harder.

If you were to mess with the ports, filling in the dead spots at the bottom of the ports and recontouring them will improve flow. You actually make them smaller and pick up power. You dont need an aftermarket head unless you cant find any good ones, the stock head can make plenty of power, even the 2V does pretty well with the right cam intake and headers.

The Cleveland was a race engine detuned for the street, not a pedestrian chunk of iron that needed lots of aftermarket help to make decent power. Feel free to waste time and money throwing more parts at it though. All it needs is a cam and headers.

rmodel65

word of advice pull the heads install new valves ask me how i know

72MachOne99GT

So general consensus is work with the parts that are already on the car.

I knew the Cleveland heads were good flowing heads, I just wasn't sure if it was cost effective to look aftermarket. That pretty plainly seems to be a no.

I'd pretty much settled on finally convincing him to do headers back as far as exhaust goes.

Does a cam really wake the car up that much?

I'll check on the gear ratio, but like already said, I'm sure it's limping around on some long legged highway gears.

If it were up to me I'd go with 4.10's like I have in my '99, but since it's my dads car, I doubt he'll want to touch that.

THUMPIN455

They like 3.55 gears with the mild cams I mentioned above. More cam means more gear. Replacing the valves is a good idea, cheap insurance since they are almost 40 years old. A bud of mine had 4.10 gears behind a 4 speed 4V, it ran pretty good but we never got to line them up and he didnt take it to the track. If he drives it on the highway much he wont like the 4.10, even the 3.50 gear spins the engine pretty tight at 60-70mph. unless he wants to put in an overdrive or he wants to go drag racing, stay with the milder gears.

The cam makes a big difference, I'll know how well the XE274 works in a low compression 2V sometime soon. Its the first XE cam I have tried in a Cleveland, but after how the 270H and 280H ran, I can imagine it should thump pretty good. A cam similar in size to any of these should work pretty well, just be sure to change the springs, locks, and retainers, and really you should do the valves too.

72MachOne99GT

How difficult is it to do valvessprings/retainers on a OHV motor like this?

I did a head swap on my '99GT but never had to take the cam off of the head and mess with springs/head assembly.

Obviously everything is right there in your view on a OHV motor. Is it generally something that can be performed with the heads still on the motor?

What's the difference in the 270 and 280 cam? One a bit more drastic than the other?

I'm basically looking for something that'll make the car feel quicker than it does now. Gears are a no brainer obviously. Would any changes need to be made to the carb with a cam swap?

I'm not a carb guy personally. I just know we upgraded to a holley *not sure of the size* when he bought the car since the stocker wasn't really alive anymore.

67mustang302

The valve job will need to be done by a competent machine shop, since the seats will need to be ground, guides replaced, then just get the kit from Comp(SK or K kit I think is cam, lifters, springs, locks, retainers and one even comes with a timing chain set). Definitely just a cam and some bolt ons will really wake it up, if you want more power for little cost then getting the ports reshaped goes a long way. But you don't need aftermarket heads on a Cleveland unless you're trying to build over 450hp from a 351.