Okay, I just ordered a set of 72cc Dart Pro 1 alum heads with the 230cc intake runners. These will be replacing my World Products S/R heads which are Iron of course. anyways I am putting these on a twin turbo engine, and am curious if there are any precautions I should be aware of with aluminum heads. I have heard that they are better than Iron in every aspect, with no drawbacks, But for instance, are they okay to o-ring? if so what kind of wire should be used? copper or steel?
Also I am needing to sell my S/R heads, so I can somewhat pay for my new ones. They are in great condition,2.020 intake, 1.60 exhaust 170cc intake runners, 1.25 comp dual springs, Ported/Polished, fully assembled, but they are O-ringed. can N/A engines perhaps using high compression setup's or nitrous benifit from the o-ring. I am trying to find good selling points for these heads. Anyone want to buy them?
Actually an iron head will make more power vs the EXACT same aluminum head. Iron retains more heat which helps in cumbustion. Aluminum has it's advantages is weight of course, but also dissipate heat faster allowing a higher compression ratio with lower octane. All around aluminum is the way to go. :cheers:
Aluminum dissipates heat faster than iron, which on one hand means that the heat/pressure energy generated by combustion will move away from the combustion chamber/piston, which means less pressure differential above/below piston, which is less force. However, it also has the tendency to reduce local hot spots, which reduces the chances of preignition. This means you can run a higher static compression ratio with aluminum heads, which has the effect of increasing the efficiency of the combustion process.
Increases in dynamic compression ratios do result in more full throttle power, but also an even proportionately greater increase part throttle (low volumetric efficiency) power. That means better gas mileage.
I don't know if a fair test could be done on an iron head vs aluminum head once you compensate for compression. The compression ratios and differences in compression ratios would also depend on valve timing, intake efficiency, etc...
Seems like those in the know usually run aluminum, but there are some die hard iron head fans who have pretty damn fast cars. Personally I'll stick with aluminum though.
Aluminum heads are a good choice and Dart has some of the best. You should use a copper gasket if available as it is softer. No need to O ring these heads unless a supercharger is being used. However if you do require such a modification stainless or copper wire will work. Copper wire may nick and stainless is stronger and takes more abuse in removal and reinstalling heads.lI run A LS 7 with their heads in a 68 Camaro and it required special longer head bolts and longer push rods. In order to get the benefit from these heads as they require higher RPM`s to function, a good solid lifter cam shaft should be used. If a hydraulic is used there will not be much of a noticable improvement as the RPM is limited. I use solid lifer engines almost exclusively in most of my pieces. Avoid roller cams and roller rockers as it`s just more junk to F--- up. Those parts require constant maintenance as most applications are for race cars that are torn down after every run and inspected all the time. Reaching in over fenders to maintaine fancy parts can wreck special paint in a hurry. :chevy
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Okay, I just ordered a set of 72cc Dart Pro 1 alum heads with the 230cc intake runners. These will be replacing my World Products S/R heads which are Iron of course. anyways I am putting these on a twin turbo engine, and am curious if there are any precautions I should be aware of with aluminum heads. I have heard that they are better than Iron in every aspect, with no drawbacks, But for instance, are they okay to o-ring? if so what kind of wire should be used? copper or steel?
Also I am needing to sell my S/R heads, so I can somewhat pay for my new ones. They are in great condition,2.020 intake, 1.60 exhaust 170cc intake runners, 1.25 comp dual springs, Ported/Polished, fully assembled, but they are O-ringed. can N/A engines perhaps using high compression setup's or nitrous benifit from the o-ring. I am trying to find good selling points for these heads. Anyone want to buy them?
If the old heads themselves are o-ringed, and not the block, I wouldn't rush out and o-ring the new heads necessarily. On my twin turbo engine, I'm just running a standard Felpro 1034 composite gasket. With as much as 22 psi of boost on 93 octane, 1200+hp/1000tq, I haven't had any problems. Detontation is what blows heads gaskets, at least at the boost/cylinder pressures we will likely run. If you're running 45 psi of boost like the NMCA/NSCA guys, then that's another story. If you have a good tune and are detonation free, I'd recommend using a conventional gasket. While many people are successful at running copper gaskets on the street without coolant leakage, I prefer to keep the gasket as the weak link. You could think of the gasket as a fuse in the event the engine does detonate for some reason. It's much cheaper and easier to replace a headgasket than a piston.
As for selling your already o-ringed S/R heads, N20 guys can benefit from the o-rings.
Another option which is a nice compromise between a conventional compostie gasket, and a copper/o-ring gasket is Felpro's Wireloc gasket. It has a small wire oring already built into it, but it's a composite gasket which doesn't suffer from the coolant leakage problems of a copper gasket. With the addition of a reciever groove machined in the cylinder head, you get benefit of an o-ring, with out the potential problems of a copper gasket.
Another option which is a nice compromise between a conventional compostie gasket, and a copper/o-ring gasket is Felpro's Wireloc gasket. It has a small wire oring already built into it, but it's a composite gasket which doesn't suffer from the coolant leakage problems of a copper gasket. With the addition of a reciever groove machined in the cylinder head, you get benefit of an o-ring, with out the potential problems of a copper gasket. Monty this is what I used and it has been trouble free for three years.
HMMM.. That is really good to hear, I was told that after 12psi it is good to o-ring, So I did, My previous setup with the heads worked like a charm, I didn't leak. Though I only had the heads o-ringed and the block does not have a reciever groove.
I am also putting in a new cam, Though it is a hyd roller, I was going to go with a solid, but was talked into going the other route cause they stated that it is much less maintance. I don't know these things since I am only 21 and learning along the way:( I hope to be one bad @ss engine builder someday.
I need to get my hands on the DD2000 so I can start playing around with some other issues I have. I began looking into my lower end the other day, But let me fill you all in on where I started. I bought the car from a guy who had a crate engine from Performacnce Products in Texas. The Invoice states Forged flattop pistons, stage 3 rods, stage 1 crankshaft. The later 2 are the ones that I am questioning, since they don't say wether they are cast or forged has really thrown me in a loophole. I was originally going to pull out my pistons to go for a 22cc dished piston but it was rather hard to find a forged set with a 40 over bore. And a guy at a local shop told me it would be just fine to use a spacer "93thousands" copper gasket to get my compression down. So I did that, later I was told that was an extreemly stupid thing to do, and I will detionate all day long. Though I have not detionated yet and was running 14 pounds before I tore it all down. I am now thinking of doing things the right way and first making sure I have a forged crank and rods. second, I am almost certain I am going to replace the pistons finally with some dished and lose this damm 93 thousands gasket.
Anyways no local shop has a dd2000 so do they have a site you can download it? if so how much?
Get some custom made pistons and get rid of that thick gasket. I'm using a .038 head gasket and the D shaped piston is flush with the top of the block but the dish lowers the c/r to 9-1
Also I am needing to sell my S/R heads, so I can somewhat pay for my new ones. They are in great condition,2.020 intake, 1.60 exhaust 170cc intake runners, 1.25 comp dual springs, Ported/Polished, fully assembled, but they are O-ringed. can N/A engines perhaps using high compression setup's or nitrous benifit from the o-ring. I am trying to find good selling points for these heads. Anyone want to buy them?
How much for the iron heads? Who did the port work? Do you have flow #'s for them? :cheers:
I don't know what the flow numbers are now. Oh and I have no idea how much they are worth now, it's basically if and when someone offers me a price that I think is good, otherwise I am just going to give them to my dad to put on his vett, or my ship them to an old friend in cali to put on his vett.
I am going to get my hands on a digital camera this weekend to take some pictures of them, along with some other goodies I have like some carbon fiber valve covers.
I am going to dig into my bottom end tomarrow "today for some of you east coast guys" to determine if I have a forged crank or not. If I remember right, I believe I noticed some machine cut marks on the counter weights making the shape of them. I don't know any other way to determine whether it's forged or not. Anyone have any other suggestions on how to properly identify one?
As for new pistons, I need to find out what my compression is, I have the block decked, so the pistons come flush with the top, 5.7 rods, I don't know the crank, pretty sure what ever the standard throw on them is what I have, 72cc heads, and am currently looking into some 22cc dished pistons. Anyone have any idea what this might caculate to? If so what would the difference be with a .040 copper gasket? or .060?
To determine whether your crank is forged or not, just look at the counter weights. A cast crank will have a wide casting line through the counter weight, while a forged piece will have either a narrow line or no line and will be fully machined.
Well I have not looked at the crank as of yet, though I believe it looked machined when I looked a good while back. But I did get ahold of the shop that originally built the engine, they stated that it is a cast crank. So I am now looking for a complete forged Rotating Assembly, I posted a new topic reagarding this in more detail.
To determine whether your crank is forged or not, just look at the counter weights. A cast crank will have a wide casting line through the counter weight, while a forged piece will have either a narrow line or no line
Ah, Monty? Sure you don't have that explanation turned around? :)
I got my heads today, Just test fitted everything, I guess I always run into problems that most people don't have, For instance, my turbos are placed over the valve covers. These Pro-1's have a raised valve cover rail. So my turbo's would not fit. I ended up putting a dent in the cover on the corner where the turbo was hitting to make the clearance. I hooked up a set of rockers and what not and put some putty on the inside of the cover so see how much clearance I have, Fortunatly they did not touch, Then again I am not sure how hydro lifters really operate. Do they create more lift at high RPM or what? Then again I have another cam comming in on the 15th with even more lift. I hope to god that I will still have clearance if not, then CRAP I might have to find new manifolds for my turbos. :( this is getting out of hand.
Location: down that one road next to that big tree
Re: Iron Vs. Aluminum heads (WashingtonRacer)
i used the wirelock fel-pros on my engine, slightly overkill for a 420hp SBC, maybe, but i couldn't come up with a reason not to. NO coolant leakage and NO problems, very nice gasket.
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Iron Vs. Aluminum heads
