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R/T Superbee
Dodge Dakota
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12/04/2002
23:17:59
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 Subject: Aluminum or Cast Heads?
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I'm looking for some input from those that know.
What do you all think is better Aluminum or Cast R/T heads? And 1.92 or 2.02?
I'm looking to do this on a 00' R/T with JBA headers & exaust, cold air, chip, 180' therm, MSD6A, and 1.7 RR's.
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Big DAK
Dodge Dakota
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12/05/2002
22:28:59
|  RE: Aluminum or Cast Heads?
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You won't feel the effects of 2.02 heads unless you over 5300 rpms.But if your truck starts breathing at 5000 they would be good.
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POWER HUNGRY
Dodge Dakota
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12/05/2002
22:30:15
|  RE: Aluminum or Cast Heads?
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I've tried getting info on the aluminum heads also without any luck. I like the idea of saving 50+lbs of the front end. I think the real down point I see is the massive price difference about $770 for bare 1.92 R/t vs. $1375 for bare alum. heads(P4876624). There is a large port alum. head out(P4876786) but I can't find any info on it either. I did hear that the iron heads come with rough ports that should be cleaned up, so that might be something to think about when making your choice.
As for 1.92 vs. 2.02. On Krcperformance.com they say that their 2.02 ported head out flowed the ported 1.92 even at low lift, so I'd go with the 2.02.
If you find anything else on the aluminum heads keep us informed.
Good luck
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R/T Superbee
Dodge Dakota
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12/05/2002
23:11:12
| RE: Aluminum or Cast Heads?
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I here you can't use headers with the aluminum heads. If that is true then there is no debate
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HSKR
Dodge Dakota
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12/06/2002
00:12:39
| RE: Aluminum or Cast Heads?
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You can use headers with the aluminum heads, but the ports on the headers are smaller than the output of the heads so you restrict a little of the flow on the exhaust side. There is a new header coming out that will work with the R/T and aluminum heads with no restriction though. If what you said in your other post on the M1 thread is true, then you don't want the 2.02 heads. I would stick with the 1.92 R/T heads. What are your future plans for your truck mod wise?? Aluminum heads increase compression ratio to about 10:1. I've aso heard they stand a better chance of warping if you use nitrous. There are some good message boards that are strictly R/T related. I suggest you check them out and get info from there. Who better to get info about mods from than other R/T owners??
http://forums.delphiforums.com/dakotart
http://groups.yahoo.com/group/dakotart
he delphi forums is really good for info, and has some people with a lot of knowledge about these trucks, especially heads/cam info.
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Shane
Dodge Dakota
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12/06/2002
18:32:40
| RE: Aluminum or Cast Heads?
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The increased comp ratio is because aluminum takes more heat out of the combustion chamber. which is like lowering the ratio, the cast heads stock and r/t cast are both 60cc heads the alum is 53cc altho i have never seen 2.02's either. I have a s/c so the heat loss and weight loss alone are worth the 1,300 to me.
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Lab Rat
GenIII
12/06/2002
20:53:41
| RE: Aluminum or Cast Heads?
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Shane, the material of the heads has nothing to do with C/R. The difference comes from the combustion chamber volume, as you pointed out. Lower volume = higher C/R due to less reexpansion at TDC.
LR
Gibson Dual Sport, AirForce One air intake, Jet II, Jet TBS, 180 stat, IAT, TPS, no viscous fan, Lakewood traction bars, "Wilson" antenna ball...when are we gonna see some real parts??!!
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HSKR
Dodge Dakota
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12/07/2002
00:12:24
| RE: Aluminum or Cast Heads?
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My truck I am picking up next weekend has 2.02 aluminum heads on it. and as pointed out the compression ratio is higher because of the smaller chamber not the masterial, but aluminum heads can get away with higher compression rations because of the better heat dissapation with the aluminum.
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DeepDak
Dodge Dakota
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12/07/2002
00:37:18
| RE: Aluminum or Cast Heads?
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HSKR,
Do you know the stock intake/exhaust port sizes on a stock 5.9 head?
What is included in the $770 R/T heads? Rocker, retainer, springs, etc or are these parts seperate?
Didn't you have IB R/T? Bought a new one?
Eli
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kota on 20s
GenIII
12/07/2002
02:06:29
| RE: Aluminum or Cast Heads?
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he HAD blue truck...untill he wrapped the frontend around a railroad tie...(how high was that thing sticking up by the way?)
he is getting a PIMP white one!!
what other mods does it have dude? sounds like a beast!
~Eric
superdupercharged, M-1, 1.7 RR's, 52mm TB, ceramic headers, 3" carsound cat, and gibson muffler
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HSKR
Dodge Dakota
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12/07/2002
02:35:10
| RE: Aluminum or Cast Heads?
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Stock heads are 1.92 intake valves and 1.6 exhuast I beleive. Same as the low end R/T heads, but the R/T heads have better intake port design and larger combustion chambers. Not asure which heads you are talking about. I got my ported and polished 2.02 R/T heads for $1650 fully assembled ready to bolt on with valve srpings and retainers. Just had to put on rockers and push rods. I had a '99 IB CC R/T, but as Eric said, I got ina fight with a railroad tie protecting a firehydrant and lost the battle. Totaled the blue truck out. I'm buying a '00 BW CC R/T to replace it with. Comes with the aluminum heads mentioned, 4bbl M1, Comp Cams 512 lift cam, ported TB, K&N GenII, Mopar headers, Dynomax cat back, Holley Billet fuel rails, Cervini's SS Ram air hood, CheckMate tonneau, fully rebuilt tranny with kevlar bands and shift kit, Hotchkis Suspension, Chrome R/T wheels, and aftermarket custom stereo with 12" sub. Oh yeah, and has a Viper alarm on it. Probably some other small things I'm forgetting.
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kota on 20s
GenIII
12/07/2002
02:41:35
| RE: Aluminum or Cast Heads?
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oh falk! that sounds like a beast dude!! you going to put it on the bottle, or boost it?
~Eric
superdupercharged, M-1, 1.7 RR's, 52mm TB, ceramic headers, 3" carsound cat, and gibson muffler
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HSKR
Dodge Dakota
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12/07/2002
02:58:05
| RE: Aluminum or Cast Heads?
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Havn't decided yet. The cam was ground for an SC since the truck had an ATI Procharger on it at one time. Talking with Mark Bellisimo(winner of overall sport truck in Tucson) who ran a 12.3 in Tucson on the bottle with a 200shot, and he said the truck was just as fast as his on the bottle when it had the ATI on it.
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kota on 20s
GenIII
12/07/2002
03:04:25
| RE: Aluminum or Cast Heads?
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yeah, marks truck was/is tight.
damn, since it has the cam, go with the SC dude! you dont have to worry about getting popped for having the line hooked up, or bottle pressure and the power will always be on tap. throw in a alky injectoion kit, and knock even more time off.
~Eric
superdupercharged, M-1, 1.7 RR's, 52mm TB, ceramic headers, 3" carsound cat, and gibson muffler
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426hemi
Dodge Dakota
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12/07/2002
03:22:20
| RE: Aluminum or Cast Heads?
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you can forget aluminum heads. only mopar has them, and they have 53cc chambers. they will not run on a magnum engine on pump gas. also 2.02 heads will kill all your low end torque, unless you have alot of cam. stick with the magnum r/t cast iron heads with 1.92/ 1.625 valves (stock). unless you want to knock and ping like hell!
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kota on 20s
GenIII
12/07/2002
03:30:15
| RE: Aluminum or Cast Heads?
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"unless you have a lot of cam"? umm.. wouldnt that take MORE away from the bottom end?
have you ever tried ANY head yourself?
why would a engine "knock and ping like hell" with a set of heads? there are A LOT of people runing the 1.97 and 2.02 heads with no problems.
BTW, i dont know the owner of the truck that HSKR is buying his truck from, but i am 99.99999999999% sure it runs on unleaded just fine
what mods do YOU have on YOUR dakota?
~Eric
superdupercharged, M-1, 1.7 RR's, 52mm TB, ceramic headers, 3" carsound cat, and gibson muffler
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426hemi
Dodge Dakota
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12/07/2002
04:12:13
| RE: Aluminum or Cast Heads?
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my dak is an 01 quad cab 5.9, comp cams cust. grind (similar to r/t cam),mpp mag r/t heads, 1.6 crower's, bilett tb, edelbrock headers, k&n cold air, msd 6al, cats removed, flowmaster, other tweaking. oh, and by the way, tried both sets of heads. 15 years of building race boat motors tells me that when you reduce the size of the combustion chamber, you increase compression and heat build up, which with the wrong fuel mixture (pump gas without at least a serious additive) will cause the motor to knock and ping like hell. one note, my dak is an 01 with no perf. computer available. i have had no luck with flashes. however, you may have possible better results with earlier models that have perf. ecu's available.
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kota on 20s
GenIII
12/07/2002
04:39:33
| RE: Aluminum or Cast Heads?
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well, i dont build race engines, but i know when you up the CR, you will have to run a higher octain fuel. i REALLY doubt that the CR gets raised enough where you have to run 100+ octain.
even if it is, you could always run the felpro gasktes. they are a bit thicker than stock, and that will bring the CR down a tad.
~Eric
superdupercharged, M-1, 1.7 RR's, 52mm TB, ceramic headers, 3" carsound cat, and gibson muffler
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Shane
Dodge Dakota
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12/07/2002
18:51:55
| RE: Aluminum or Cast Heads?
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I think you guys miss understood what i was saying i will explain it better. Aluminum takes more heat out of the combustion chamber than cast iron does. the effect on the engine performance is like lowering the compression ratio. so the heads are designed to have one more point of compression ratio. this is done by making a smaller combustion chamber. The higher mechanical ratio puts more heat into the combustion mixture, balancing due to the loss of heat.
Hope that clears up what i was babbling about.
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silly
Dodge Dakota
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12/07/2002
20:39:25
| RE: Aluminum or Cast Heads?
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bottom line is that aluminum doesn`t get hot spots like cast iron. that causes the det, the high comp will run fine on pump 92-94 gas with no pinging, if it does you have your timing to far advanced. the smaller the cc in the combustion chamber the higher the comp, it doesn`t need the huge cc volume because the intake is limiting breathing, you can deck your heads to raise comp, but once you do it once good luck on doing it again.
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sandman
Dodge Dakota
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12/07/2002
23:52:09
| RE: Aluminum or Cast Heads?
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I like aluminum for the following reasons.
1)You can easily weld them up and resurface if you crack one.
2)They lower octane requirments for any given compression ratio by disapateing heat better.
3) They save you alot of weight 7lbs of weight equals 1 HP.
4) They machine easier and you can get a much smoother surface with them when you are polishing them.
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big_torque
Dodge Dakota
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12/08/2002
10:08:27
| RE: Aluminum or Cast Heads?
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7lbs = 1 HP ? what you mean ?
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HSKR
Dodge Dakota
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12/08/2002
12:19:31
| RE: Aluminum or Cast Heads?
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426hemi:
The aluminum R/T heads run just fine on pump gas. The aluminum dissapates heat afster so the higher compression ratio doesn't affect it on the pump gas. So much for 15 years of engine building experience. If you really had that much experience, you woudl have known that.
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MikeD
*R/T*
12/08/2002
12:35:35
| RE: Aluminum or Cast Heads?
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I've dynoed my truck w/ a set of 1.92 R/T heads when I was shipped the wrong ones from KRC...were supposed to be 2.02 and realized they weren't the right set when I had my truck stripped down...so I put the 1.92 heads on it till I had the right set.
I dynoed at 313rwhp and 338rwtq w/ the set of 1.92's.
Then I got the right set of heads, ported and polished 2.02 R/T heads and dynoed at 309rwhp and 322rwtq. I lost some torque and showed I was leaning out at about 15 A/F ratio on the dyno. I've been trying to figure out how to richen it up so I bought 24# injectors...well that helped a little but not enough. I thought it might be I need a new flash but I called Marty and I'm gonna have to add a high flow fuel pump to get the engine all the fuel it needs.
So keep in mind the 1.92 R/T heads are badass but in order to make the 2.02 heads badass U gotta drown the big heads in fuel so it'll require fuel system modifications to get the full potential out of them.
Oh and that comment about not feeling the heads past 5300...you will need to get a stall in order to get the rpms high enough to feel them. I can feel mine if I punch it in the stall range of 2100-2400, it'll knock you back in your seat.
Hopes this helps your decision!
~Mike~
Get In...Sit Down...Shutup...& Hangon
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sandman
Dodge Dakota
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12/08/2002
13:45:56
| RE: Aluminum or Cast Heads?
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What I mean is that for every 7lbs of weight you vechile loses it is the same as gaining 1 more HP and the wheels interms of performance. If you had two engine with almost identical head designs, power output and compression ration the one with aluminum heads will disapate heat faster. This is a cool feature because the engine becomes is better able to handle lower octane gas with out pinging or detonation. So while it might still be best for you run Sunoco 94 octane in your mean machine you are not going to put a hole in the pston if you have no choice but you run midgrade in it due to shortage of Sunoco 94. This not too big of a problem for us here in the USA but try getting good gas in Mexico on a reliable bases or Africa.......For total durability and cheap initial cost cast iron is hard to beat but I would rather have Aluminum. Some diesel engines have Aluminum heads now so that tells you how much better they are now at being durable!
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sandman
Dodge Dakota
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12/08/2002
13:46:15
| RE: Aluminum or Cast Heads?
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What I mean is that for every 7lbs of weight you vechile loses it is the same as gaining 1 more HP and the wheels interms of performance. If you had two engine with almost identical head designs, power output and compression ration the one with aluminum heads will disapate heat faster. This is a cool feature because the engine becomes is better able to handle lower octane gas with out pinging or detonation. So while it might still be best for you run Sunoco 94 octane in your mean machine you are not going to put a hole in the pston if you have no choice but you run midgrade in it due to shortage of Sunoco 94. This not too big of a problem for us here in the USA but try getting good gas in Mexico on a reliable bases or Africa.......For total durability and cheap initial cost cast iron is hard to beat but I would rather have Aluminum. Some diesel engines have Aluminum heads now so that tells you how much better they are now at being durable!
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big_torque
Dodge Dakota
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12/08/2002
17:25:24
| RE: Aluminum or Cast Heads?
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Dakotas (GenIII) are about 4000 lbs. with about 200 to the wheels. Wouldnt it be 20:1 ? Vipers are about 8.5 : 1........ 7lbs/1 rwhp is an insanely fast car.
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Lab Rat
GenIII
12/08/2002
18:33:26
| RE: Aluminum or Cast Heads?
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WOW! So if you can make your truck weightless, as in put it in orbit, you would instantly gain 571 HP. Add to that the existing 235 and you're over 800 HP.
When is the next Shuttle flight??
LR
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POWER HUNGRY
Dodge Dakota
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12/08/2002
19:37:03
| RE: Aluminum or Cast Heads?
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DeepDak,
The $770 price was out of the mopar catalog for "bare" heads I.E. no valves, springs or retainers.
As for the weight savings to horsepower conversion when it relates to mph is not constant. Its 15lbs=1hp when your running 95mph trap speed. Weight becomes more important the faster you run. By the time you get to a trap speed of 110mph the weight to power conversion drops to 9.6lbs=1hp. The mopar performance street truck book has the easiest charts to understand and even takes into account the trans. your running.
Has anyone seen a site that sells or has more info. on the aluminum heads???
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BIG DAK
Dodge Dakota
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12/09/2002
01:56:32
| RE: Aluminum or Cast Heads?
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Mike d i said you won't feel the effects of 2.02 heads untill you hit 5300 rpms and above.And you would need more than just a stall t.c if your cam isn't any good to 5300 plus it dosen't matter.You may have all that i don't know.
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dodge
Dodge Dakota
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12/10/2002
01:24:14
| RE: Aluminum or Cast Heads?
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You better do alot more to yor truck if you want to run 2.02 heads
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