I am putting together a good, solid 350 for my '71 Roadster. It's going to be a very healthy street engine with a goal of good low end torque. I have forged pistons, a roller cam, 4 bolt mains, mated to a 4-speed. Now I am ready to purchase heads and am trying to decide between AFR 180 or 195. I am leaning heavily toward the 180s, but before I plunk down my $1,500, I wanted to run it by the C3 tech crowd to see if there is a viable dissenting opinion.

What do you think? 195 or 180?

 

Post your cam specs. A better decision between the two then can be made.
Eddie

 

we need to see your cam specs....Gordonm and I both have the AFR heads, I have the 180's and he has 190's, there's not much flow difference between the two so either heads can be a good choice....

 

All my searching has determined that the 180 is appropriate for a street 350, the 195's 200's are for serious race motors. The 180 provides better numbers for low end torque

 

It's a pretty mild cam, should be good for the street though.

http://cranecams.com/index.php?show=...21&lvl=2&prt=5

 

What rear gear and tranny?

The cam seems too small for anything but a tow-truck. I'd at least go with something in the 220* at .50 range. Also, if you're running headers, good exhaust and some AFR's, ditch the dual pattern.

 

go 180 with that cam.

 

3.36 rear end, wide ratio Muncie 4-speed.

 

It is 214/220 @ .050. A mild performance cam for a 350. The 180 heads will be very good with that cam on a 350.

 

You have a nice bottom end and plan on spending serious coin for heads but that cam isn't even close to complimenting the rest of your engine build. What is your computed static compression? That cam is less than the L-79 327 cam or the 350 L-82 cam and the popular Summit 1103 and 1104. If you are shooting for 10:1 with the aluminum heads I would consider using the LT-1 solid lifter cam or at least the stock L-82 cam and advance it 4 degrees for some more bottom end.
If not going for the higher compression why not use the Dart Platinum heads?

 

I can return the cam for something else, that's not a problem. It's still in the box. My other choice was this one (234°/242°).

http://cranecams.com/?show=browsePar...tType=camshaft

 

What did you think of the HR-284? It looks like a nice street performance cam with duration numbers of 222/230.

 

Yeah, I'd at least go 222* at .50 on the intake side (which is about what the old Chevy "151" cam was (used in 350 HP 327's).

But with good exhaust and heads, dual pattern will cost you ponies.

Here's a good link from the First Gen Camaro page:

http://www.camaros.net/forums/showth...+pattern+smith

 

Pretty radical extremes on the camshaft.

What the fast majority of people do not understand is there is a balance between duration and intake cc of the heads. A lower duration camshaft with larger volume cc heads can make the exact same power and powerband as a longer duration camshaft with smaller cc heads.

At one time I was sponsored by a dyno shop so I literally have dozens upon dozens of dyno sheets of different combinations. By happenstance a friend was over this weekend trying to figure out what he wants to do with his 96 CE LT4 so we went through quiet a few difference combinations

Strangely enough one of the sheets that caught my eye compares my LT4 when all I did was modified air intake with K+N filter, adjustable fuel pressure gauge, long tube headers, very good dual 3” exhaust, ported LT4 intake and GTP ported heads. STOCK CAM…… It made 360 rwhp.

On the same sheet was my old 97 SS Camaro with LPE 211/219 cam, shorty headers, LT1 ported intake and GTP ported LT1 heads. Obviously more cam but smaller heads. The two dyno runs were virtually identical to each other.

The general trend these days is shorter duration cams and larger cc volume in the heads. I realize this goes against what John Lingenfelter wrote in his book, but his book is getting dated and we all are learning more all the time.

Really depends upon intended application but I’d do the larger heads in a heartbeat and try a moderate cam. Cams are somewhat cheap in the big picture and not that hard to change. Another important thing is having a combo with good intake and good exhaust to take advantage of the increased air flow.

Whatever you do, put some money aside for tuning and debugging. The vast majority of people are making way less that what they should be making because they didn’t take the time to dot the I’s and cross the T’s.

Anyone can slop parts together; making them work is another story.

 

check with AFR and see what they recommend, they have released a better flowing version of there 195, it's called the "Eliminator" I believe. Not sure if they improved upon the 180. Make sure whatever you get is the latest from AFR, don't get stuck with an older version that's sat on a shelf somewhere, probably won't since AFR is always back-ordered.
Just my 02
Good Luck

 

What do you think? 195 or 180?

I've been considering upgrading my heads and intake, see my sig for my current set up.

 

I'd go with the 195's,..which is a 'medium' sized head these days.

 

Will make a ton of torque for a 350.

 

For your 383 run the new 195s. These new ones flow better tha n a lot ofthe 210s on the market. I make over 500 HP with a set of 195s on my 383 with a big solid flat tappet cam

 

180 on the 350 street engine. 195 on the 383