Aftermarket heads on stock pistons?

speedfreek · Aug 19, 2008

I have a stock 454 that I was wondering if I could put on a good set of heads (Brodix,Edel,Dart,etc.) on with the stock pistons? My plans are to buy a solid roller, heads and intake and put on my engine.

Would this be ok?

camaroman7d · Aug 19, 2008

Changing the heads won't cause an issue at all. Just check to see what combustion chamber size you need to put your compression where you want it and go for it. The same goes for the cam and intake, these items are the basics for building power and these changes are made every day.

speedfreek · Aug 19, 2008

camaroman7d said:
Check to see what combustion chamber size you need to put your compression where you want it and go for it. The same goes for the cam and intake, these items are the basics for building power and these changes are made every day.

I think this truck engine has 7.5:1comp. Ugh, I've been doing alot of research. thanks

pdq67 · Aug 19, 2008

Small dish Flat-tops, eh??

7.9 to 1..

pdq67

speedfreek · Aug 19, 2008

pdq67 said:
Small dish Flat-tops, eh??

7.9 to 1..

pdq67

I have not tore into the engine yet. I hope it's at least 7.9:1

btw: I have read many times about your "tow truck" big block engine that makes over 500hp easily. My goal is 650fwhp.

77wolf10.85 · Aug 19, 2008

Good heads is the #1 power maker. The heads don't care what the pistons may be. Go for it guy, just do like Royce said and buy the cc chamber you need.

speedfreek · Aug 19, 2008

77wolf10.85 said:
Good heads is the #1 power maker. The heads don't care what the pistons may be. Go for it guy, just do like Royce said and buy the cc chamber you need.

Rekon what cc I would need if this engine has stock pistons?

I know where a pair of 781's are. But I don't know the comb chamber size. Also I'm not sure if I should get them (781's) or aftrmrkt ones. Wanting 650+hp.

Casey Kilfoyle · Aug 20, 2008

Buy the 781's and spary it! Then you can get a good rotating assy and heads down the road and get your 650hp naturally aspirated.

speedfreek · Aug 20, 2008

Casey Kilfoyle said:
Buy the 781's and spary it! Then you can get a good rotating assy and heads down the road and get your 650hp naturally aspirated.

The stock pistons won't hold spray. I got the money now to get a good top end kit.

speedshifter · Aug 20, 2008

I have a couple sets of 049s, it is said they can be made to flow enough air to make 650hp. Big chambers though, so they need to be milled, maybe even angle milled, to make adequate compression with flat tops. It's really hard to make a good CR on a big block with stock pistons and factory open chamber heads. Pretty much have to mill the snot out of them or get dome pistons, or both.

speedshifter · Aug 20, 2008

Got the coin for a new top end kit? Brodix has some nice stuff...

http://www.brodix.com/heads/topendcombos.html

(I've drooled there.)

speedfreek · Aug 20, 2008

speedshifter said:
Big chambers though, so they need to be milled, maybe even angle milled, to make adequate compression with flat tops. It's really hard to make a good CR on a big block with stock pistons and factory open chamber heads. Pretty much have to mill the snot out of them or get dome pistons, or both.

This is where I thought I would have problems with my stock pistons.

speedshifter said:
Got the coin for a new top end kit? Brodix has some nice stuff...

http://www.brodix.com/heads/topendcombos.html

(I've drooled there.)

http://store.summitracing.com/partdetail.asp?part=BRO-9992000-3&autoview=sku
Yep, this would be a great price. Just looking for someone that knows OR a proven combo with cam that will produce 650hp.

I wish brodix, merlin, world and others advertised combos like Edelbrock does with their dyno proven combos so you'll know what you can achieve with their heads.

speedshifter · Aug 20, 2008

speedfreek said:
I wish brodix, merlin, world and others advertised combos like Edelbrock does with their dyno proven combos so you'll know what you can achieve with their heads.

Both good and bad on the "proven combos." Most engine builders like to run their own cam, pistons, etc. I personally don't care to run the same combo as everyone else. JMHO.

Also, some have found it difficult to duplicate the "proven combo" horsepower on their real-life engines at home.

To an extent, intake flow numbers @ 28" water drop can give you a fairly accurate clue as to horsepower potential of a cylinder head. Multiply cfm @ your max valve lift by 2.06 and you'll be in the ballpark.

Casey Kilfoyle · Aug 20, 2008

Choose heads with the long term goal in mind. The stock pistons are going to hold you back from making any decent hp. I used the DART PRO ONE 335 cnc heads on a 496 and made 730 hp on pump gas. The combo is a little bit on the radical side though. Brodix has a good head that would work with milling until you get decent pistons. For a 468 down the road, the BB-2 Plus is good with 110-114cc chambers, or the STS BB-2 Plus on a 496 with same chambers. Buy a good head with the overall goal in mind (good pistons). Pistons are cheaper than heads. Then spray it!

phel69 · Aug 20, 2008

If you are starting with flat tops then you don't want or need 781's or 049's. They are 116-122cc's stock and would cost you more than a set of new aftermarket small chamber heads to get to a usable size for you. Waste of time and money due to the fact that you would need extensive milling, porting, bigger valves etc...
They can be great heads for a higher compression engine, I ran 781's with 540+ hp, but they like compression.
You probably need a head closer to the 100cc range. Heads, cam and good smaller tube headers will get you over 500 hp done right but 650 hp on flat tops will take some work with a BIG solid roller cam, great heads, bigger headers, 3 in. exhaust and probably soft until 3500 rpm.
I personally think if you get over 500hp and can use it to hook you will be more than happy. This is if you are using your car on the street of course. Track is a different story.

speedshifter · Aug 20, 2008

Casey Kilfoyle said:
Pistons are cheaper than heads.

phel69 said:
If you are starting with flat tops then you don't want or need 781's or 049's.

Yes, maybe your plan to put a fancy top end on a stock short block is a bit backwards. One of my plans is to build a fordged long rod 468 with my 049s for an easy 650 hp. I have a 4" steel crank, a few cylinder blocks to try, a Team G intake, and the heads. Just need to put this all together with some good machine work, a big solid cam and go. If I ever want more I can go with nice heads or feed it a bottle.

Aftermarket heads on stock pistons?

speedfreek

camaroman7d

speedfreek

pdq67

speedfreek

77wolf10.85

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Casey Kilfoyle

speedfreek

speedshifter

speedshifter

speedfreek

speedshifter

Casey Kilfoyle

phel69

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