Cbrakllr

iTrader: (2)

Ok here is my plan, major power on the strip!!! I dont car if my car has no top end or anything like that. I want to run fast in the 1/4. Im looking in to heads and dont know which ones to go with, as in my sig i have the MS3 (not yet installed) so i need something that works well with that! I was looking at AFR's 225cc but they seem too pricey. but I dont know if their 205cc head would be good enough so i looked into the dart 225's and they are much much cheaper, why? Are they just as good? what head would be good for my application?

Matt D

iTrader: (49)

Why not go with the PRC LS6 heads? They are out flowing the AFRs across the board, are more than $1000 less, and keep your stock PtoV clearance.

30th t/a

iTrader: (51)

afr 205s. do some searching and you'll find these heads are the most proven heads to make killer power ALL THE TIME. thats a fact ....not opinion.

Cbrakllr

iTrader: (2)

Damn both yall kno what ur talkin bout, now im lost id ont know what to do???

Matt from outlaw what are the heads you are talking about? website or anything like that would be kool.

tbojbob

I'm guessing Matt is talkin' bout these from TSP:

http://www.texas-speed.com/shop/item...d=649&catid=40

Dollar wise they are a heck of a bargain, you could get a 90/90 set up with the money you saved! Personally haven't seen anything quantifying the performance of the DARTS, either size. That being said AFR's have been the pinnacle LS1 performance head that have stock valve train geometry (valve angle, rocker arm stand configuration). It's all in how much you want to spend, is 400 rwhp OK? Or, did you have 450+ as your goal.........

bluecamaroz28

Will these PRC LS6 CNC Ported Heads be able to turn 450RWHP with Trex, MS3 or G5X3??? Stock intake and Throttle body off course.

Matt D

iTrader: (49)

I am not trying to start a flame war here as we have seen both heads put out great numbers, both on the dyno and at the strip. I'm am all about making the most power with the least amount of money. The new program that Texas Speed has been using for their heads is awesome. You tell me which is better.

Intake PRCs AFRs
.200" 149 140
.300" 205 200
.400" 255 251
.500" 287 281
.600" 307 298
.625" 310 N/A

mvonada

Matt, thanks for jumping in here. The Texas Speed heads are hard to beat when you are talking $ vs hp! Thats some serious low cost hp!

gollum

iTrader: (1)

The as cast Darts combustion chambers have lots of sharp edges that need to be CNC'd and hand polished before bolting on.

n2o

iTrader: (1)

What about max 346 ci performance? There does not appear to be an "end all" solution to our head dilema. What about a rectangle port (LS7ish) with an intake that will fit the gen III motors?

kp

iTrader: (34)

hmm, mine seem to be OK and seem to run just fine. I didnt see anything worst then OE heads.

Dart331Stroker

IN particular what sharp edges are you refering to? I have been over these heads alot, and dont see any "sharp" edges. If you are refering to the sharp angles and the sharp angle where the seats meet, there is a reason for that. You would have to see how the fuel shears off the seats during the wet flow bench testing to understand.

JC

Tony Mamo @ AFR

iTrader: (13)

Gonna throw in my three cents here...

First penny.....Don't bother comparing advertised flow numbers from different manufacturers (there's about 100 threads about that situation).

Second penny.....There's ALOT more to making power than purely looking at flow data (even if it is off of the same bench and can then be used to compare). Again....many threads touch on this subject...port volume, proper cross-sectional area, and airspeed all pay big dividends in cylinder fill and reversion dampening.

Third penny.....The answer to your question lies in doing some research. Spend the time digging around the dyno section and look to see which independent numbers are always strong (non-shop cars and leg humpers excluded as well).

Then pretend they all cost the same and make a determination based on the research youve acquired. Then consider that cylinder head selection is the most important decision you will make that will effect your end results with the most impact (good or bad). Spending more money for a better head pays for itself in the long run.....Ultimately you will always come back looking for what you left under the table in your first go around. How many threads like THAT have you seen??

BTW....The Dart piece is an excellent head for the money and offers a stronger casting as well, but comparing an as cast head to a fully CNC ported extremely optimized AFR is kind of silly if your looking for ALL the money out of a particular combo.

Feel free to contact me at AFR if you have any questions....

Thanks,
Tony Mamo
(818)890-0616 Ext. 109

gollum

iTrader: (1)

What about hot spots in the combustion chamber? Wouldn't the sharp area between the seats lead to detonation/pre ignition? When your CNC versions are released will this area will be deburred and smoothed?

I also noticed with the 205 versions that the intake valve seats appeared to be cut deaper than the exhaust seats and intake valves are shorter that the exhaust valves. Was this done to allow more valve free drop @ TDC?

What is the free drop ( 205 vs. 225 using OEM gasket)?

Dart331Stroker

The area between the seats or where they meet dont get hot, the fuel cools the intake seat as it enters the chamber. Again we spent alot of time developing the valve job, and doing extensive wet flow testing, if you look on here you will see a post refering to wet flow testing at ReherMorrison. We showed Darrin Morgan alot of the information regarding wet flow testing, he has been here and worked with Tony McAfee, this would be our Tony. LOL. Anyways the sharper angle helps the fuel to shear of the seat, if you were to round it the fuel would follow that radius and seperate from the air, this obviously would be bad. We have tried to show this on high speed equipment, but do to the dye that is used in the wet flow process we havent found a way to show this on video. We have some people here now from some of the magazines who are very intrigued with the information they are learning and look forward to releasing this data in the upcoming months in several magazines. Other then the seat there are no sharp edges, we even deburr the chamber edges leading to the quench areas.

Thanks
JC

kp

iTrader: (34)

Good post Tony but lets look at the other side of the third coin for a second

Fist off, as you said, comparing a 'budget' as-cast head to fully CNC head really isnt fair - cant argue that.

But lets say someone was doing a budget nitrous build, they might be inclined to think that the 1000.00 or so difference can pay for a cam and nitrous kit. Or a 'budget' turbo guy can spend the extra 1000.00 on an BOV and an intercooler. While its true the as-cast dart would most likely fall short of the AFR n/a, with nitrous or a turbo that 10-20rwhp difference might not mean so much anymore if one can achieve their HP goals overall.

Biggest mistake is simply assuming just because you use an AFR, ET or any other 'top shelf' cylinder head you are guaranteed big power without the proper supporting pieces, thats a bigger mistake then choosing the wrong head over others. There is a big enough market where no one should be complaining, since supply is always a probelm it appears that all aftermarket LSx heads are selling well.

FWIW I picked the Darts because they were cheap, I am cheap - I'll admit it. But I also have had good luck with Dart products over the years and just assumed they wouldnt turn out a piece of junk. I paid for them just like anyone else (actually I paid more) and they suit my needs just fine. If I had an unlimited budget I would have a set of AFR 225s or ETs on the car, but then again if I had an unlimited budget I would have a 402 and twin T67s instead of a 346 and a D1SC also

Patrick G

iTrader: (14)

Even though this is a Dart vs. AFR thread, I'll engage this comment. First off, 243 casting LS6 heads have been available to head porters since late 2000. Many, many competant head porters have modified them for the past 5-6 years. And during that time, there have been many a 243 head that produced flow numbers in the range of the PRC CNC'd 243 heads. That said, how come you RARELY saw stock diplacement dynos above 430 rwhp before the AFR 205s came out? The flow numbers were there. Hmmm....maybe the flow numbers don't tell the whole story.

If you recall, the AFR 205s were met with a lot of skepticism because their numbers were on average 15-20 rwhp than other popular heads on the market...even after you sifted out the shop cars and leg humpers. The reasons the AFRs exceeded the norm went way beyond the flow numbers alone. The port velocity (gives more power under the curve), the combustion chamber shape (gives a more efficient burn) and complete execution of the parts could have only been accomplished with a clean sheet design. Porting a factory 243 casting has limitations in overall power and strength.

These are areas where the Dart and AFR castings are worth their extra entry fee. You get what you pay for. Now as far as Darts vs. AFRs go, I would have to say that until Dart brings their fully CNC'd casting to the marketplace, they will not have a product that is ready to beat AFR.

n20_kid

go darts all the way i have seen both the heads and i got the dart and the darts flowed 315 out of the box on a low reading bench. (225) Richard maskins (the owner of dart) said he has got people pulling off ls6 ported heads and 5.3 ported heads and putting his unported heads on out of the box and going quicker.

Tony Mamo @ AFR

iTrader: (13)

I hear you loud and clear....Thankfully this is America and there are many products to choose from. Some have a better fit than others and what's "right" for one guy might be "wrong" for the next. You knew you would make so much power with that combo, the money saved on heads could be used for something else. A guy trying to make big numbers N/A might not have that luxury and knowing his goals would have to purchase what he felt was the "best" for his application.

It's all good....there is plenty of market share to go around and more than enough Gen III business to keep all the quality cylinder head companies thriving.

Tony M.

Matt D

iTrader: (49)

Like Kevin said, I guess I am just cheap. For the extra $1000 or so I saved from going with the Darts or PRCs I could do something else to make up for the 15-20 hp gain. AFR makes a great clyinder head, but there are better options out there for the budget friendly racer. That is all I was trying to say. Good luck with whatever head company you decide to go with.