What exactly are the specs of an L82 head? I've tried to research with no luck. All I really know about them is that they are 2.02/1.60 heads with screw in studs and come with a combustion chamber ranging from 74-76cc. Does anyone know the size of the intake and exhaust runners?

I was getting ready to purchase Dart Iron Eagle to help increase the flow and bump the compression on L82. I was talking to the previous owner yesterday and he says he installed dome top TRWs when he had the engine bored and the compression was 10:1. I was thinking about maybe going with 180cc runner darts. Now, that the previous owner tells me that the compression is 10:1. Which puts the 64cc out of the picture and kind of makes me feel like im wasting my money with the 72cc's. Especially, if the L82 runners are around 175-180cc - I don't know if that is the actual size.

I know my dad sure put alot of money and time in his original L82 heads and based on the performance of the car, they flow quite well. Another reason for going to dart was to avoid the excessive amounts of time my dad put in his heads to achieve the flow characteristics it possesses. However, I will put that extra time if it will save me a lot more money!

I wont make any final decision until after I have the engine apart because I'm doubting the 10:1 compression. My dad's car is 10.26:1 and if you stand behind the car right by the exhaust, it feels like someone is gently slapping your leg. This doesn't really seem to be the case for my engine.

 

I just found a website... Still no answer, but my guess is the intake runners are anywhere from 160 - 170. My guess is closer to 160? Seems like LT-1's and DZ302's had 160cc? The 461 and 461X castings, I believe had 165cc and 170cc runners, but had no accessory bolt holes. Since the L82's were the high performance smog head, does that mean the are 160cc?

 

MY 79's were 2.02/1.60 76 cc and 165 cc intake. Pull you heads and look at the pistons.

200 cc run nice on 350 ci

 

That was my initial plan. A couple of people told me the 200's work great on a 350. Then I went to compare my planned set up vs. Trick Flow's top end kits. I plan on using the Performer RPM cam which is kind of similar to the cam used in the 490 HP kit and this kit uses 195's. The only difference is the performer RPM cam has only 2 degrees more duration on the exhaust and the duration at .050 is a little less than the TFS cam. So, my thoughts were that the kit is only engineered for top end power where as the edelbrocks is more mid range to top end power. Then I look at TFS's 420HP kit and they also use the 195's on a decent sized cam but obviously smaller than the Performer RPM.

Then I start thinking about people who say the Performer RPM is a dog until 3000. Through my experience that has not been the case. My dad's running the Performer RPM top end kit on his L82 with the original but reworked heads and 10.26:1 comp. and the engine runs like a champ. Low-end, mid-range, and top-end, the car is pretty responsive no matter the RPM. So, then I start thinking: well, if I use the 200's maybe I will experience the doginess of this cam at the lower RPM's. I know I would get the extra HP my dad lacks at the top, but then I start thinking: how often do I rev the crap out of my engine? (not very much)

I try asking my dad for his opinion since he's was an engine builder and has built tons of BBC's for a lot of locals, but he doesn't want to give me a straight answer. I know there is a huge difference in building a BBC and building a SBC, but I think he doesn't want to tell me to go with a 200cc because he is not as familiar with SB's as he is with the BB's.

George, I know you built many strong small blocks, and I think you might be able to give me a better answer. On a street driven 355, with that much cam, would you go with 180cc's or the 200cc's? FYI, this engine will be backed by a T56 and a 3.55 rear end. Even though 6th is a highway gear, I think it maybe useless until I swap for something like a 4:11. However, I want to run it first with a 3.55 and see how it does.
The first the 3 gears are approx. 2.64, 1.74, and 1.25 (9.37, 6.18, 4.44). I would really appreciate your thoughts!

 

Youngster....I am pretty sure that the stock heads are 165cc.I have a set of 64cc 461 heads,and picked up a solid lifter 310 cam,and lifters earlier,and some Harland Sharps,but the rockers are for my car.
You better come get this L82 over here.I'm having "thoughts"!

 

Dart heads will answer your questions on runner size ph # 248-362-1188, my guess with a hydraulic flat tappit cam in a 355 they will most likely say 180 runner.

You can get into the iron eagle platinum with a 200 runner.

 

Rid yourself of those thoughts!! I'm very seriously thinking about using that engine and setting mine to the side.

Thanks for the number. I tried calling them on tuesday, but got no answer (holidays i imagine). I'll try again.

 

The head port cc is only a small part of the whole equasion. The total whole dead air space from the back of the valve to the end of the runner determines how soon you get port velocity when the intake valve opens.

The cam overlap determines how much reversion is caused to impead the initial flow of air when the intake opens.

So smarter engine builders figured out that big CFM flowing heads and a smaller cam duration were far superior to to some numb nuts hot cam and small head build up.

The numb nuts build up has that bad *** lumpy sounding cam when he pulls in the parking lot. But it is all show an no go.


The fastest cars are always the well planned out machines with the highest power average over the widest RPM. Shifting takes time. Like building a very peaky TQ courve with 110 or less LCA. You don't want a motor that you have to down shift to pass somebody. You want a wide TQ courve, like 3000 - 3500 rpm wide.

I used the Crane power max 278 cam with good heads and 1.6 rockers for about 10 years. It was about the best all around cam for my 3.55 geared auto tranny.

If you want iron heads, the Dart platinum 200 cc from jegs are a good buy. Then for a cam I would use the Crane 278 in either h-flat or s-flat. For the intake manifold I would get the Weiand Stealth and a 600 -650 carb for instant on power