Hot Rod Forum banner
Status
Not open for further replies.

Best heads for street performance 355

24K views 39 replies 16 participants last post by  4 Jaw Chuck 
#1 ·
I am sure that the topic has been beat to death, but : My buddy has a fresh 355 with flat top pistons and a "Thumpr" cam. The heads are factory smog heads. I am thinking they are 662 heads but it has been several months since I installed the cam and am not sure. So I was wondering what would be the best heads to upgrade this engine for street use. It is going to go in a "67 Camaro which had the factory 250 cu. in. 6 cyl. We will be using the original powerglide trans and rearend with a 2200 rpm stall converter. He is talking "Dart" heads, but aren't there different heads for different applications ? He will be running a 1406 Eddy on a performer intake.
 
#32 ·
Very true. I am running World cast iron heads, 67cc chambers, intake and exhaust runners extensively ported, on a 383 stroker, comp thumpr cam, flat top hyper pistons, scat 9000 crank, Holley single plane intake port matched to the heads, and I am very happy with them. Sure they're not fancy aluminum heads, and I'm sure there are better heads out there, but just for a personal basis, World makes a great head
 
#3 ·
Most would agree the "Best" street heads right now are AFRs if they are selected properly and the rest of the build is a combination of gears, converter, cam, heads, intake and carb that suits the purpose of the car.
That said, many heads available will do the job and unless you are a sharp tuner, you will never notice the difference in most.
 
#4 ·
Yes "most" aftermarket heads fit light to light applications. But good enough has never been in my vocabulary in terms of hot rodding.And these days you can tailor a torque curve with correct matched parts for a desired result for the street.It is the sum total of all the little things added up that makes a big difference.
 
#7 ·
You have no idea how hard I tried to talk him out of the thumpr. He had what I thought was a good cam in it. The engine was a fresh professional rebuild with so few miles on it that the carbon on top of the pistons wiped off with a rag. Don't remember the numbers or make of the cam right now, but when I researched it, it turned out to be a performance cam for a 327. I think it would have worked great. My thoughts, which may well be wrong, would be any performance head with runners no bigger than 180 cc and 72 cc chambers would be a big improvement to go with the flattops and pump gas. Summit Racing has so many different Dart heads listed. I was hoping someone would point me in the right direction for a good street head for pump gas with the flattops and thumpr cam. Still open for suggestions. :D I will tell him about the AFR heads and the shp 180s Thanks :thumbup:
 
#6 ·
brodix they have nice thick decks.. but like said above, the type/size depends on engine and vehicle use..
deck thickness is important if you are going to add boost or happy gas.. and no matter what type of p.i.t.a. it is to remove them in the car. on engine use arp studs leave the head bolts in the coffee can
 
#9 ·
haha, so true, but because there are more cruiser type cars out there than all out power, you have guys that want the wild cam sound without the b/s that goes with them..
can't blame them, if I had a 40's merc that I'd never race or a 34 ford that was just a cruiser,,
they fit the mold great,
they also allow those on a shoestring budget to use heads no one else would and that= cheap..
most of the grinds are just overdone early 80's grinds.. remember when good heads where for the big money crowd..
 
#11 ·
the Summit and Jegs house brand heads are both very good heads, about the best you'll find for the money. some of the chinese heads aren't bad either, but they're chinese so take that for what you want. AFR's are nice, but you're paying a lot more for a cnc ported head- at that price level you're in a whole different market and there are also other very good heads in that market.
 
#12 ·
best heads for street performance 355

consider vortec heads they come stock on chevy and gmc trucks. you have to use vortec intake to match heads the runners out flow most aftermarket heads and are a lot cheaper my son put a set on his project truck. it has 350 bored 30 over flat top pistons and bigger cam gained 50+ hp
 
#14 ·
SOME of the Dart heads are really good, the SHP 180 heads are NOT those heads. I wouldn't even consider using them unless they were given to you.

Brodix, Jegs, Summit, all are at the same price range and much better (Jegs being the best IMO). You can also get cheaper Assault Racing heads which are better than the shp's but are chinese (I have nothing against that but many people do).

AFR's are also pretty good but cost a lot more- you can also go with some RHS heads or go to a custom head guy like Speir or Dr. J for something that is really top notch (but you'll have to pay for it).
 
#16 ·
Not a thing wrong with the SHP 180 heads. As a matter of fact, the SHP 180 was the head they did the development work on for the platinum upgrade on the Pro 1 heads.

People look at the flow numbers and say "blah". What they forget or don't understand is the ports were developed with wetflow tech which is whole nother ballpark. Not uncommon so see dry flow numbers go down but add a gasoline/air mixture and its a different story.
 
#19 ·
And the info regarding the SHP head was smoke and mirrors as well lol, wet flow tech is great, but it means nothing in this instance. Put the SHP180 against an AFR180 or a Profiler180 on a dyno and see where the wetflow testing got you. Technology is only as good as the people wielding it.
 
#23 · (Edited)
Buddy, I'm not getting into a **** measuring contest with you. I can post the results of where the DART SHP 200 head beat your vaunted Profiler heads in a dyno test. You can do the research yourself (hint, nasty z28). I really don't want to hear about CNC ported heads vs as cast heads either from an AFR fan boy. Ahhh, what the heck. You ever hear of a guy named Shariroff? Here's a nice little engine making over 400 hp with 9.2:1 CR running on 87 octane cat pee. 350 RealStreet Small Block Chevrolet Crate Engine Yeah, crappy head. Put any head of the same price and you'll be around the same power give or take 5 hp. At least you know with Dart you're getting a quality head that will just plain work.
 
#25 ·
sorry. but not so new. went away for a while and came back. total posts are probably double yours. I just started looking thru the topics and saw your opinions. You know what they say about those. The Dart SHP 180 head's intake port flows the same as the 200's port because they used that head to develop the platinum design changes. Fantastic head for the money. but that's just a professional head porter and engine builder talking. Where did you say your shop was?

BTW, genius, the thread was active which kind of explains why it was at the top of the engine forum when I logged in. Carry on.
 
#26 ·
Lol....like you said, its just an opinion.... you have yours, then there's the right one. Its no sweat of my balls which head you use or recomend.
The numbers dont lie.... nor do some of the best in the business
Chad Speier - Profiler
Eric Weingartner - Pro filer
Darrin Morgin, I'm fairly certain that ones a no brainer....
Here your numbers, (hint, nastyz28)
Pro filer 185 flow data
185cc with 2.02 Valves
.200 135 110
.300 201 145
.400 245 180
.500 265 206
.600 270 213
Dart SHP 180 flow numbers
180ccLift INT EX
.200 139 114
.300 190 145
.400 218 164
.500 222 172
.600 218 174
Again....a fairly dumb argument....
 
#28 ·
throwing names around,,,Scott and Jeff both use their CNC machines on heads they buy at very good prices(somehow) and sell crate engines that do exactly what they claim. A racer friend from Calgary biught an engine from Scott for a sportsman class and the engine never failed and performed well. When John freshened his race car engine he saw some of the tricks that made the power.I assure you the heads did not come out of a box and get directly bolted to any engines,they get a few minor improvements that work.You cannot duplicate their engines or power levels just by bolting same parts together
 
#33 ·
Let's get something straight. A user asked whats wrong with the Dart SHP castings. I answered and you gave your erroneous opinion. In reply to your latest....yeah, this Eric Weingartner

-16-2013, 12:31 AM #2 Weingartner Racing
Member
Pullin gears



Join Date: May 2009
Posts: 858


Re: dart SHP heads
I have tested both the 180cc and the 200cc heads with the 64cc but not the 180cc with 72cc chamber. The 180cc is better than the 200cc head. It flows almost the same as the larger 200cc head. It has the newer platinum intake port. However both share the same non platinum chamber and exhaust port.
__________________
Eric Weingartner
Weingartner Racing LLC
918-520-3480
weingartner@cox.net
www.wengines.com
 
#35 ·
Let's get something straight. A user asked whats wrong with the Dart SHP castings. I answered and you gave your erroneous opinion. In reply to your latest....yeah, this Eric Weingartner

-16-2013, 12:31 AM #2 Weingartner Racing
Member
Pullin gears



Join Date: May 2009
Posts: 858


Re: dart SHP heads
I have tested both the 180cc and the 200cc heads with the 64cc but not the 180cc with 72cc chamber. The 180cc is better than the 200cc head. It flows almost the same as the larger 200cc head. It has the newer platinum intake port. However both share the same non platinum chamber and exhaust port.
__________________
Eric Weingartner
Weingartner Racing LLC
918-520-3480
weingartner@cox.net
www.wengines.com
OK? So Eric thinks the 180 dart is better then the 200 dart? And this means what exactly? How is this relivant?
My statement was,and still is, for a few dollars LESS then the Darts, you can have a better head in the Profiler 185....
That's it, thats all.... if your a Dart fan, and looking to purchase heads from them and them only, then your argument about which of their SHP castings is better then by all means, argue on McDuck..
Are we good now? Because clearly were talking about 2 different issues.....
 
#37 ·
Lol..... I think it was straightforward. If I have $1100 and you have $1100, and I buy Profiler 185 heads, and you purchase Dart SHP 180 heads, I'm getting a better head for my hard earned dollar.
Its OK tho, the Darts work just fine too......
I'm happy being a LOSER....were a good bunch of lads....anytime you wanna swing by we always have beer in the fridge and something apart in the garage, your more then welcome :D
Have a Merry Christmas!
 
Status
Not open for further replies.
You have insufficient privileges to reply here.
Top