StraubTech

This is a drag engine so it is a stout cam

.700/640
26X/27X
109 Sep

StraubTech

The company they have contracted I must say, it is the nicest offshore casting I have ever seen.

63mako

NO. Reread my post. I have recommended other heads for budget builds. For some builds vortec heads are fine. If you get a great deal on a set of used heads you can retrofit for your needs and save some money that is great. I bet this was the case with the 225 PRO MAXX heads. That said the best flow and smallest port that works for your specific application will provide the best streetability, results, throttle response and power per cc of port size. A bigger I/E ratio will also allow a smaller duration exhaust lobe and less overlap further increasing streetability, bottom end and vacuum. If that cost an extra $3-400 you have to weigh if that is acceptable for your needs and budget. I recently CC'd a set of Dart 180 heads because of a gasket, intake mismatch. They had 193 CC intake ports out of the box and a 10 CC (65 vs 75) bigger exhaust port that flows less than the AFR port.

augiedoggy

here's a thread from a machine shop who was not impressed with a customers new AFR heads...
http://speedtalk.com/forum/viewtopic.php?f=1&t=31802

and another that had an expensive failure twice.
http://speedtalk.com/forum/viewtopic...28650&start=15

again point is depending on how many were sold you can find cases of unsatisfied customers and defects everywhere... I do agree that AFR heads are some of the best.... just trying to point out you cant stereotype all promaxx or economy cost heads by the experiences of a few.

augiedoggy

That I do believe about dart heads. Ive read of many finding variances from spec on them... Mine were close even though I was hoping the 64cc chambers would error on the larger side to lower my compression.

As I've stated before I think people are overly influenced and persuaded that they need to spend more than some have for top dollar parts. I Don't care for the fact that the benefit of the doubt is never given it seems... someone will bring up a question about a champion radiator or summit cam and all the responses come back suggesting they should be using dewitts or roller cams... It just gets old watching people being discouraged into buying a crate engine. and the same components always being suggested regardless of application or budget. even when a vortec head gets brought up there is often someone who chimes in and seems to get enjoyment out of discouraging the idea and scaring an uneducated consumer with things like lift limitations and special intakes when its likely they will be replacing the intake and going with a mild cam anyway..

bluedawg

it's personal preference that leads me to suggest the part or combo and that preference is derived from experience from using said parts. I always ask what the budget is and intended use and make my suggestions off of that. I've suggested import heads that have been gone through and as was stated that's $1k add port work to make them competitive if not better and your looking at $1800 or better. If a guy has enough experience to port his own heads he's not likely going to be asking for head recommendations on the forum, so telling him to port them with limited knowledge and no flow bench is wrong, he might get lucky but I doubt it. There's only two real things I don't like about vortec and that's the manifold and lift issues. To say you never get a bargin is a blanket statement, you can find good deals every now and then, but in my case every time I skimp on parts to save money I usually get what I pay for.

oops!

MotorHead

Promaxx heads ???, that's an all out race effort, running mixed race gas, why try and save a few bucks, my T&D shaft rocker were $1300. By the time you pay for the heads and pay for the porting you can get CNC'ed AFR heads

Solid LT1

My guess on the Pro Maxx heads? They wont go over 10K miles without some kind of failure due to low quality parts or machining unless the major parts like valve guides and seats are replaced by a competant machinist with some appreciation for the fit/finish required for a quality part. Who cares how much HP they make if they wont go the distance same can be said for many other brands of cylinder heads including AFR in my expiriences

StraubTech

The combination based on ones budget and power expectations. Don't expect to put a $1K set of heads on a 440 CID engine and make 700HP, but don't think you have to spend $3500 on heads to do it either.

63mako

If they go 10,000 miles they are awesome. This is not a street engine, Drag only.
There is always someone faster.
406 Callies bottom end, 14.8 to 1 compression, Brodix 10X 23 degree heads, Cam is Solid roller 288 and 294 duration @ .50, 740 Gross lift, 111 LSA. Final Dyno # was 715 Max HP and 654 Max torque.
https://www.corvetteforum.com/forums...q-406-a-2.html

cv67

Been doing that forever
Mine were advertised at 200 they poured damn near 220.
Always wondered why the 350 never really "hit". At the time I was too young and didnt know any better to ck things. Had guide issues also right off the bat. Poured thousands into them making them "right"...soon as the Elims came out these became dinosaurs lol. Cars strong but bet when I get a few dollars to blow there will be some AFRs on there.

jb78L-82

I have actually thought about the longevity issue when I read about budget this or budget that part that is just as good as so and so well known part. I always wonder "but how long will that budget part last before something lets go?"

68post

Problem is .. you don't know when the "quality" suppliers have also went to the dark side.
Everything is now suspect, or should be, because of greed - competition or "profits for investors " ,( ie.. the constant need for more profit within corporations ).

I trust less and require proof of quality more often. As time passes you'd best educate yourself to make any purchase. "Caveat emptor".

68post

Forgot to mention .. nice engine..

augiedoggy

Exactly!

jb78L-82

Let's put it another way, I am less likely to trust and push my luck with a set of $700 chinese heads than with a company like AFR. Everything is suspect today but it is all about taking calculated risks….

It also depends heavily on the part, ease of replacement if ti fails, and the dollars involved. For example, when I was just doing 6 month ago the Hemi V8 Chrysler Front brake system upgrade (dual piston versus single piston, 14 inch rotors versus 12 inch rotors) on my 300 Limited 3.5 V6, I left the rear brakes stock 12 inch solid rotors but changed the 12 inch rotors to drilled/slotted ones (china) with new PF pads-cost $80 for both. Mistake! The new pads were dragging since they fit too tight in the caliper bracket and cracked the chinese rotors after 7,000 miles. Granted the pad was dragging but other chinese rotors I have used on other cars warp after about 30,000 miles on the front brakes. I replaced the rear rotors on the the chrysler with American made high carbon steel rotors from Centric-2X the price of the chinese rotors- $80 each and glad to use them. I avoid China products at all costs now if I can which is sometimes impossible.

augiedoggy

I was pushing my luck when I decided to buy a 40 year old car made during one of GM's worse "quality control" decades.... But the way I figure is you cant get very far by never taking chances...

MotorHead

Fast, Reliable and Cheap, pick two

Little Mouse

What was the quality of a china car 40 yrs ago ? They won't even make a drill bit today without it being crap.

Next door neighbor bought a set of pro/crap head oval port the valve covers would not even bolt on without him doing some grinding. He called Skip White Gipper. They told him a $250.00 restocking fee on the $900.00 set of heads he bought, he's stuck with the crap.

tt 383

The turbo world has seen an influx of offshore units and they seem to working very well, the head casters seem to be on the same learning curve and some reputable names offer their own "label" cheap ported head based off those.