[MUSLCAH]

Looking for a little lumpy idle cam to work in a stock 1964 389 4 bbl ..stock 303 hp motor...it has the stock slim Jim auto...but looking at changing that next winter. Didn't know if the stock tri power cam would fit the bill ? Thanks for any help

[b-man]

Best choice in my opinion would be the tried and true 068 Tri-Power cam.

A mild to moderate factory performance cam is exactly what is needed in an otherwise stock engine that's tugging a heavy full-size car.

[Stuart]

There are probably modern cam grinds that are better for performance, but the 068 is hard to beat. It makes power and has a great idle - lumpy, but not too lumpy. It's just right.

[Greg Reid]

Just for your information...the Melling 068 is listed by most places at around $165 plus shipping. Some of this stuff we use in this hobby is still just considered auto parts by the rest of the world. So...
I checked Autozone...I got it with an online rebate, free shipping to my door, for right at around half that price. Even without the rebate, they beat the average price by $50 or so.
http://www.autozone.com/internal-eng...170511121419:s

[61-63]

You may also want to consider a 744 cam which sits between an 068 and an 041 RAIV cam. It is lumpier than an 068 but still has the low valve lift the 068 has so you shouldn't have to worry about valve springs or pistons hitting valves. Allmost all modern grinds start getting into higher valve lift. As the other posters said an 068 is good but to me it just barely has a hint of lump to it. I have an 068 in a carb flow test engine on an stand and the 744 in a '63 Catalina and you definitely hear more lump from the 744, but it is still very streetable.

[ponyakr]

I had a '69 RA3 4-speed with a 744 cam. It had a definite small lump in the idle you could hear. I liked it. After 60k + street miles I raced it for 2 seasons. With slicks, it ran mid 13's. Only change from original was a replacement timing set.

BUT, when I recommended this cam on another forum, a guy came on saying it was a bad choice, because it required stronger valve springs than the 068, He said that even tho it didn't have more lift, the shape of it's lobes made stronger springs necessary.

So, if the OP wants to make this cam change without changing springs, this MIGHT be a consideration. I can't verify whether the 744 needs more spring pressure or not. Maybe some of you guys know for sure.

Greg is right about Auto Zone. They consistently have the best price on the Melling 068 clone (SPC-7)

http://www.ebay.com/itm/Engine-Camsh...RYlsIl&vxp=mtr

The 744 clone (SPC-3) is usually cheaper from another Ebay seller.

http://www.ebay.com/itm/Engine-Camsh...lYmKMN&vxp=mtr

If the OP don't mind changing springs, he might consider a Lunati 10510312. It has a little more lift than the 068 & 744, but a .050 lift duration somewhere between the two.

221/230 @ .050, .454 lift, 112 LSA

https://www.summitracing.com/parts/lun-10510312

http://www.jegs.com/i/Lunati/638/10510312/10002/-1

I'm not familiar with 389 heads. But, if they have a 1.6 installed spring height, I assume the CC 988-16 springs will work with either the 744 or the small Lunati, since CC recommends them for their XE 262 cam.

http://www.compcams.com/catalog/204_205.html

https://www.ebay.com/p/?iid=13142286...pp=true&chn=ps

[tom s]

You have to remember your heads have pressed in studs.Stay with the 068 as it was used in many engines with those studs.The 744 and 041 only came in engines with screew in studs.Dont look for higher ratio rockers IMO for same reason.Tom

[ponyakr]

This brings up a question. Exactly how much cam & spring pressure is safe with press-in studs ? Anybody know ?

I've read of some guys using bigger than stock cam/springs with press-in studs, with no problems. So, what are safe limits ? Or, really, is anything safe with press-in studs ? Or, is it a gamble, regardless of what cam or springs you have ?

https://www.google.com/search?q=how+...hrome&ie=UTF-8

[tom s]

Crap shoot,the factory had oversize studs avail incase of a pulled one.I would just pound them back down untill they would just not stay .Finally pulled the heads and did it right.In everyday driving they seemed to be fine,with high RPMs and valve float it would pull them. Tom

[61-63]

The '63 engine I have the 744 in has pressed in studs and whatever springs the owner before me had installed when he had the engine rebuilt before I bought the car. The car was an original 2bbl 389 slimjim open rear end car and was that configuration
when I bought it. I have no idea what cam was installed when the previous owner had the engine rebuilt but it was mild and had no lope at all. I changed the car over to a 4 speed 3.23 saf-t-track, tripower car and put the 744 cam in it, without doing anything at all to the lower end or the heads. I do not race it and it does not see high revs consistently, but has done fine as is and runs pretty good and sounds good. If I were going to race it I would go much bigger on the cam than the 744, and would get better heads and put screw in studs in them, but for what I am doing I do not feel that is necessary.

'64 - '66 GTOs all had press in studs as did '61-'64 425a and 421HO big cars and many of them were spun up pretty good many times over without problems. The cams they all had from the factory had valve lift identical to or within a hair of the 744.

MUSLCAH as you describe your car, and if it were me, I wouldn't worry about the studs or the springs unless you install a cam that will open the valves beyond .430 or so. Sounds like you just want some lope and if that is so then the 068 will give you a little and the 744 a little more. Beyond them and you probably do need to start changing stuff in addition to the cam. One of the Summit cams has the same numbers as the 744 but the lift is up around .470 I think it is.

[tom s]

I only say it as a possibility as it did happen to me when I was young and dumb!Tom

[MUSLCAH]

Yup...just want it to sound good at a street light and pulling into a cruise nite.....some low end and mid range power would be nice....just a cruiser....and when I get another tranny in it....maybe a few 4800 rpm shifts...but not many.

[Engine-Ear]

Another vote for the 068 and Walker 17749 mufflers. DONE. (IMO)

[Deadhead]

If you have an auto & AC etc., the 068 might be a better choice. With a 744 you are really at the edge of streetable & vac demands of a big car. Don't get me wrong, I loved a 421 with a 744, but there is a lot of torque there, & in traffic from light to light you sound awesome & run strong, but she is ready to GO not stop. You will NEVER regret an 068/SPC7. It is the most enjoyable all round cam.

[MUSLCAH]

Thanks for all the input....no AC in this car

[carcrazy]

To me it is the 068 cam for this application. I've run a 744 and generally it needs a little more rear gear than you likely have.

[Greg Reid]

IF you decide to run the 068, you should be able to get one at a good price from Melling (SPC-7) through NAPA. I got one for under $100 delivered (Autozone).

[TeeTopZ]

I just ordered from AutoZone. About $100 delivered with the 20% off code MAY20

[Greg Reid]

I post too much. I just realized that I had already posted the 068/Autozone info earlier in this thread. I was thinking about another thread...lol