I'm looking for a set of aluminum heads for my 72 z/28. There's so many manufacturers out there now, and they all claim they're the best. Dart,Brodix,Trick Flow,Edelbrock.......has anyone used any of theese or another manufacturer? Besides the 60lbs. less weight difference are they performing better? How much did you pay? and where did you purchase them? Would I be better off with what Dart or Edelbrock sell as a full package or should I get "bare" heads and peice them together with Manley valves, coomp springs etc.etc. Ihaven't seen a cyl. head comparo in any of the magazines(afraid of pissing off advertisers?) or consumer reports. Has anybody seen something like this anywhere? Thanks...:bowtie:

You will usually get what you pay for. What you pay will depend on what horsepower level you are looking for. There are many good manufactures - AFR, Eddy, Trick Flow, Canfield, Brodix, Dart, RHS, and a host of others. Unless you know what you're doing with heads, buy the complete set. My bang for the buck line crossed at Eddy RPM's. For budget builds, it's hard to beat chevy's Vortec unit. Last word - run far and fast from the off shore knock offs. This subject has been hashed over many times in this and the hi-po forums, so use the search feature and you'll gain a wealth of knowledge.

The Dart Pro 1 Platinum and the AFR Eliminator seem to be the hot setup now, with the Dart’s a little cheaper alternative. Other than the weight savings, either cast iron or aluminum can be made to perform as well as the other. I haven’t used either of these, but I have the Dart Iron eagles on the street rod. It runs pretty well, so I can’t complain about the Dart products.

If you choose to get complete heads, make sure the valve springs are compatible with whatever cam you will be using. If you haven’t bought the cam, I would recommend you get the full kit and be sure everything will work together. Good luck.

Isn't a '70 LT-1 head 64/66 cc's and the '72 LT-1 head 76 cc's???

B/c of the drastic drop in compression??

pdq67

Isn't a '70 LT-1 head 64/66 cc's and the '72 LT-1 head 76 cc's???

B/c of the drastic drop in compression??

pdq67

the 70 LT-1's like my engine has these cylinder heads :

3927186....69-70...302/350......Camel hump,64cc chambers,accessory holes

#487 .... 71-72 ......350 LT-1 ...... 75cc chambers

Could I use the 70 heads? Will they bolt up? Would I have to cut reliefs in the pistons or will the valves still clear? Going from 9:1 to 11:1 will I need new rods,crank,bottom end or will what I have(stock) be alright?

Could I use the 70 heads? Will they bolt up? Would I have to cut reliefs in the pistons or will the valves still clear? Going from 9:1 to 11:1 will I need new rods,crank,bottom end or will what I have(stock) be alright?

Yes

They will bolt up

You won't have to cut reliefs unless you go to domed piston.

You won't have to change to bottom end if you keep rpm's in the 5K range.

And lastly - if you increase compression ratio to 11:1, be prepared to deal with detonating on a big scale, nothing race gas won't take care of - at $4.99 per gal. Simply put, you can not feasibly (and I say again feasibly) run a street engine at that CR. IMHO

If the '72 350 Z-28 engine still has a forged crank in it, you will be fine.. (I think it should still be forged??)..

And I do figure that you only have 4-notch flat-top forged pistons so switching to a 64 cc head and using .020" thick shim headgaskets like stock will put you right at 10 to 10.25 to 1 CR. just like the older L-48 350 engine had..

Excellent engine for a 268/270/272/274 or so cam and still burning good pump gas, imho!!

pdq67

Yes

They will bolt up

You won't have to cut reliefs unless you go to domed piston.

You won't have to change to bottom end if you keep rpm's in the 5K range.

And lastly - if you increase compression ratio to 11:1, be prepared to deal with detonating on a big scale, nothing race gas won't take care of - at $4.99 per gal. Simply put, you can not feasibly (and I say again feasibly) run a street engine at that CR. IMHO
FWIW, I run my 69 Z at stock 11:1 CR on the street (have done since '85 when it was rebuilt) w/o problems (and properly tuned) My 69 GTO runs 10.75:1 CR on a 50K mile factory motor w/o problems...so for me at least it has been feasible to run on the street w/ those CRs.

I suppose more to the point, 1972LT1 is not going to achive 11:1 CR just by dropping "186" heads on his '72 motor. A '72 Z should still have 9:1 compression w/ 72cc heads (or am I wrong?) I don't think that dropping the combustion chamber down to 64cc's will yield a 2 point increase in CR. it will go up...just not to 11:1.

I am running Dart Pro 1 200's and love them. I paid $900 new set-up with roller springs, guide plates, studs, and a stud girdle.

I thought it was 11:1 with those 64cc heads... 10:1 will be fine enough. Just exploring options...yes the motor is original #'s matching other than a mild solid cam,headers and a breakerless distributor. Can't get an HEI for mine due to lack of clearance with firewall and aircleaner. So anything I can do to get a little more power out of it. Has anyone installed an air gap style manifold?

I am running Dart Pro 1 200's and love them. I paid $900 new set-up with roller springs, guide plates, studs, and a stud girdle.
Are they aluminum or iron? Are they stock, or is there some porting or valve work done?

They are aluminum. They are the 200's, there are smaller and larger Darts. They came with the Manley severe duty valves which have undercut stems for higher flow. I am also running a blower so no port work on the intake side is neccessary. They flow well enough for my motor. My buddy runs a very small speed shop he deals with a guy who assemblys the castings any way you want. I got them so cheap because they are 72CC which is what I needed to get me compression right for the blower.

I thought it was 11:1 with those 64cc heads... 10:1 will be fine enough. Just exploring options...yes the motor is original #'s matching other than a mild solid cam,headers and a breakerless distributor. Can't get an HEI for mine due to lack of clearance with firewall and aircleaner. So anything I can do to get a little more power out of it. Has anyone installed an air gap style manifold?
You don't have the dome that an LT-1 or DZ302 have to go along with the 64cc chamber. I could be wrong but I thought that the difference between 70 & 72 was the increased combustion chamber & the piston shape. '72 is the last year for mechanical cam isn't it?

Like I said earlier..

4-notch, flat-top pistons, .020" thick shim headgaskets and 64 cc heads will be right at 10 to 10.25 to 1 CR just like a stock L-48 295hp/350 engine back in the old days!!

pdq67

didnt lt-1 & l-82 have forged flat top 2 valve relief pistons?

The 11 to 1 engines had 64 to 66 cc heads, .020" thick shims AND domed pistons.

The lower CR. engines had larger cc chambered heads and flat-tops.

pdq67

Thanks guys.....like I said earlier, just exploring options and trying to find the best deal for the car. There's just so much out there and everyone claims they are the best yet no one has done a cyl head comparo. Guess they're too scared that they'll piss off their advertisers.