First off, I am looking for recommendations on good books with cyl. head/cam/intake stuff. I know that a lot of new heads have come out lately and was just wondering if any new books have been published recently.

So here is the other question. What exactly would these flow numbers get me? Intake is going to remain ported TPI with stock base and runners for at least 6 months, but manifold change will be taking place after that. Also, what type of cam (non-roller hydraulic) recommendations would be made? Car is automatic, will keep stock rear gears until manifold change (if I go with the miniram or similar).

220cc Pro Action

Intake @28” of water
.100” 71.82
.200” 148.21
.300” 203.58
.400” 248.86
.500” 264.71
.600” 273.38
.700” 284.11

Exhaust @28” of water

.100” 56.70
.200” 101.13
.300” 158.54
.400” 177.30
.500” 185.66
.600” 192.10
.700” 195.76

200cc Pro Action
Intake:

.100 68.5
.200 134.32
.300 191.63
.400 235.96
.500 260.98
.600 268.51
.700 278.41

Exhaust:

.100 56.9
.200 100.99
.300 156.94
.400 176.85
.500 186.34
.600 190.13
.700 194.87

Assuming identical castings of Al and CI, the cast iron should produce more HP (with weight being the expense) as far as I can tell. If I were going to shoot for mid 12's in the future using these heads, would iron be beneficial over the Al?

These heads are about as cheap/good(?) as I can find right now. Haven't seen many posts around here about them though.

Thanks! -Matt-

 

What size engine are you building?

Either one of those cylinder heads has the potential to get you in the 500-540 hp range. The 200cc heads look to be more efficient since their flow numbers are very close to that of the 220cc heads. Dart heads are are not ported out of the box, unless you get them CNC ported, they are intended to be ported by the end user or engine builder. A little bowl work and a cleanup would net you some good gains.

 

I forget the exact number but I believe it is CFM x .257 x 8 cylinders = potential power. So say 275 Cfm flow. 275 x .257 x 8 = 565 Horsepower. This is theory but now we add a intake and that can reduce flow in the heads by 20 percent if you are lucky. If you exceed 25% you need to replace the intake. I know flow numbers are not everything but any engine builder can build a block the power is in the heads. The intake just takes away from them.
This is just rough but without the head flow the rest will not follow.

 

Thanks for the response Monty. The final combo will be a 383 with a miniram or stealthram (if I can get some more info on interference problems with the stealth ram by Holley).

The main problem I see so far is that the 383 engine will not be built until after Christmas time. I am doing a quick rebuild now and am in the market for a set of heads in the first place. After I got set on polishing my iron L98 castings I read that they were too thin to do portwork. Then I was going to go with Al L98 castings but found out that the World Products SportsmanII were pretty good for the price. Then after that, it just started to snowball and I ran across these.

Car is a daily driver and is going to be apart mainly because of the bottom end scrapping itself. The only details on it are KB hypereutectics with 2 valve relief, stock bottom end besides that, and a cam of advertised duration: 272 intake/282 exhaust, Duration at .050 in. cam lift: 214 intake/224 exhaust' Gross valve lift: .442 in. intake/.465 in. exhaust, Lobe separation: 112 degrees. I know this is nowhere near what the cam should be for those heads. 1.6 RRs are being used.

However I don't mind limping around in the car til December. The TPI is going to be the first restriction, then the cam if I went with these heads. I guess the main thing is: I need new heads. I can only buy one set now--not one set now and another set 7 months from now. Manifold will also remain nothing but ported until I swap with a high-rpm style.

Future goals are most definitely for a 12 second car, getting there N/A. -Matt-

 

Norval, I guess that kind of goes along with my needs for a new intake (I guess I posted a response at the same time you were writing out one). If it were feasible, I would limp around with these heads for a while, because down the road, I could reap the rewards of them.

Decesions, decesions. :confused:

 

What tranny (stall if an automatic) and gears are you running?

That 214/224 cam is obviously a good cam for a daily driver, but it's pretty small for a 383 with those heads and a Miniram or Stealthram. Something in the low 230's would probably be more appropriate without hurting drivability much if you've got the gears for it, which I hope you do considering your intake choices.

 

Sorry for the delay. I tore my engine down to the short block yesterday due to what I thought was a broken wristpin, skirt or something else noise. I found my #8 exhaust lifter 1/16th of an inch shorter than the others and concave about 1/4 of an inch. That lobe is gone, my magnetic drain plug couldn't hold any more filings, so I tore the mains and rods out today.

Rear main bearing is totally shot. All the finish has worn and only copper remains. That bearing was also heavily scored in about 5 places. The second main from the rear was no better. I skipped the third (engine still in car--didn't want crank on face) and the bearings started to get "better". Rod bearings were no better. Same deal--terrible towards the rear and they got better as you got closer to the front.

Oil pump got hungry too and ate some metal for dinner, although I bought another Melling pump because for what it must have gone through, I would have thought it would have been shrapnel. It faired pretty darn well.

So what does that mean? No money left over for heads, and probably not until mid November. Now the rock and the hard place. I have a set of the original heads, '85 circa and they are 462624's or something like that. The numbers are dancing around in my head right now. At the very least, they need to be milled because one of the chambers had a 1/4-20 screw slam into it. The valve seat also needs work. Other than that the heads are bone stock. I was going to at least get the Standard Abrasives kit and do some light port-work but even the small amount of cost of the kit is stretching my budget right now. I realize they will need to be cut for springs and have a new valve-seat. After that work is done, I don't know what the price will end up being. Only other work I will be able/have time to do now will be intake port matching.

Option B is to match up one of my 882 heads with another one that a buddy of mine has. They will both need to be cut for new springs. I dunno if people even reuse valves these days or not, so I might have to add the cost of valves too.

Option C is to sell the Vette.

Would you chose option A or B?

Also, it has been recommended to a friend of mine that knows a guy who has been racing C4s ever since they came out that with iron heads, my stock gears, stall maybe 400RPM over stock, and retaining the TPI that a good cam of choice would be the Comp Cams 280H. The specs are adv duration 280/280, at 0.050 is 230/230, valve lift with 1.6RRs (what I have) .512/.512 and LSA 110. That LSA isn't a prob with my ECM as I am running speed density and burn my own chips, but I guess it is considered one grind up from my current 214/224 grind. I think it may be too much, but like I said, this is coming from a guy who has been racing (both autoX and drag) for quite a few years.

I dunno. Confusion sets in and all the sudden everything I learned in Kindergarden suddenly got lost. Advice??? Thanks, -Matt-