Head Choices - With Domed Pistons

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billsdartgt

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Since I have had to dig in a little deeper with my current block I have been doing more reading and looking at what potential I could get from my current setup, the one choke point is my stock heads, which could end up being ok for me, but who wants ok. So I starting looking at the different head options, the one thing I haven't found is what might be available to bolt on with these TRW domed pistons. Anybody know of something that I have overlooked? Obviously I could go and have the stockers worked on but thought if Im gonna keep going might as well see what may be available, need to stay with LA style so I don't have to get another intake manifold Dang Blueprint keeps looking better all the time
 
Depends on what you want for compression. I start with that piston, set the chamber size, determine head gasket thickness I can get and then see how far out of the deck the piston deck needs to be. That’s usually ~.040-.050 out of the hole.

Once you do all that, you mock up the number one cylinder and do you half inch down fill. Calculate what you have for compression ratio and if it’s higher than you want you mill the dome down to get what you want.

Sounds difficult but it’s pretty simple really. The less dome you need to use the better. The piston is lighter. Dome height isn’t really an issue with the plug location where it is, but less dome is always better.
 
Ok, so I read the OP wrong.

Any LA non magnum head.
W2 heads
Closed chamber W2 and W5 heads IF you have zero deck with the Pistons you have, or you run a thicker head gasket or you mill the decks down on the piston to get to zero deck.
 
w 2 has a different intake bolt spacing. the old trw dome can be cut down , my old superstock 340 had that = 610 grams and 1/16" rings. aim for some quench!
 
I don’t have the number with me but they are the 11.5.1 piston. 4007042? maybe, a pict is in my valve seal thread

I guess to clarify a little more, the 915 J heads I have would seemingly work well with some port work and the actual flow numbers look good and depending on how many more setbacks I encounter this may be a path I choose. While I have gone a lot further with this engine than planned I realistically will have to draw the line at doing anything with the block or pistons, Thanks to the info here on Fabio I at least have a better setup that should work ok than where I was at and where I was going. Assessing what more I could possibly financially do the heads are a possibility, much more and the car will get pushed to the corner and covered, it’s turned into a pain in my *** right now. Most all of the heads I see have the smaller combustion chambers, which is detrimental to my engine/piston setup, so perhaps just the work on my current heads, if there is even some place still open might just be best. Thanks for the reply’s.
 
billsdartgt said:
I don’t have the number with me but they are the 11.5.1 piston. 4007042? maybe, a pict is in my valve seal thread

I guess to clarify a little more, the 915 J heads I have would seemingly work well with some port work and the actual flow numbers look good and depending on how many more setbacks I encounter this may be a path I choose. While I have gone a lot further with this engine than planned I realistically will have to draw the line at doing anything with the block or pistons, Thanks to the info here on Fabio I at least have a better setup that should work ok than where I was at and where I was going. Assessing what more I could possibly financially do the heads are a possibility, much more and the car will get pushed to the corner and covered, it’s turned into a pain in my *** right now. Most all of the heads I see have the smaller combustion chambers, which is detrimental to my engine/piston setup, so perhaps just the work on my current heads, if there is even some place still open might just be best. Thanks for the reply’s.
Click to expand...

Work on your heads. They ain’t the power killers everyone likes to claim.

The biggest issue is they 50 years old, core shift will bite you in the arse (BTDT many, too many times) and the exhaust port is wonky.

Other than that, which all can be worked around there is little wrong with them. I can pick apart the Edelbrock heads or any other equally. The exception is the Trick Flow head. For a head with OE architecture it’s the best I’ve seen but the chambers won’t work with your Pistons.

A quality valve job (with a 45* seat I used 4 angles on the intake and a radius on the exhaust) and the widest top cut you can get, blend the bowls, radius the short turns and if you are feeling froggy, reduce the size of the guide in the intake port and you’ll be happy.

My junk has to come out so before it goes back in it’s going on the dyno and we'll see what kind of a roach it is. I’ll post the results and some video here. Hopefully that will happen in June but with the country losing its mind it could be August or early 2021.
 
I run 11 s with 3418915 J heads , street car, 2.055 1.625 11/32 manley valves, chambers diameter enlarged to 4.060" with custom J E pistons and quench! big cam, 11.5 : 1 , 15* initial and 37* total , 3040 lbs. 92 octane
racecar rear.JPG
 
Thanks for the replies, in a recent thread I saw some numbers on ported 915 J heads, I think if I could get from the roughly 200ish baseline up to at least 250 or more it would give my engine quite a kick from what it will be and I still end up with an overall economical rework of an engine I was gonna throw out, financially this would make me happy, especially my wallet. Im still learning what is out there and available to work through getting this Dart together, every time I think I have gained a bit of knowledge I find even more, that is why I asked about the heads, wanted to see if I overlooked something just because I haven't found or read about it yet. Im gonna do some checking around and see if there is anybody still working with this virus thing going on that could do something for me in a quick turnaround, I have nearly lost my patience with little issues, don't want to get into another issue waiting on a pipe dream.

Here's the link I came across, thought it was some good info, my heads already have the 2.02 intakes, pretty good numbers at .50 and .60, of course that may or may not be totally accurate, 250-260ish would help me out.

Mopar LA Cylinder Head Comparison

again, thanks all for the replies.
 
Work with YR he has made high compression worked where possible and will tell you where it is not possible
you can get 5 cc out of your chambers if that helps- helps flow too
yr do you ever use two different top cut angles on the intakes
I did a set that way but the customer did not flow them

billsdart if guides are not in the budget at least knurl the stock ones
did you say if those heads had hard seats
if you keep the spring pressure down exhausts an last
but you do not want to run with recisioned seats
cheers
 
Wyrmrider said:
Work with YR he has made high compression worked where possible and will tell you where it is not possible
you can get 5 cc out of your chambers if that helps- helps flow too
yr do you ever use two different top cut angles on the intakes
I did a set that way but the customer did not flow them

billsdart if guides are not in the budget at least knurl the stock ones
did you say if those heads had hard seats
if you keep the spring pressure down exhausts an last
but you do not want to run with recisioned seats
cheers
Click to expand...

Just one top cut angle but I get it as wide as I can.
 
I won't be doing any work myself, no setup, called around this afternoon, 1 shop working, only does import stuff, another no answer, may be a bust on work for now.


@ wyrmrider, YR has already helped me some

Thanks for the info
 
so the link I posted (posting again) doesn't have values for the fully ported X head, I have done some searching but can't seem to find numbers, found plenty of references to the comparisons of the j heads though. Am I missing a thread? Anybody have the X numbers? Playing around with some theorectical numbers what ballpark my engine may produce in horsepower, one of the cool things you can see is what some of the differences do for the overall impact, head CFM really kicks it. While I may not ever build another engine its been good looking at some of these things again and some for the first time with more thought. I am going to take a look at my 351 in my Mustang when I get done messing around with this 360.

Mopar LA Cylinder Head Comparison
 
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stock X heads = flow stalls @ .500" lift with 198 cfm in / 126 ex. , very similar to J heads with 2.02. Ported 360 = .650" 253 in / 180 ex. 1977-80 40279596 360 head .500" 197 in. / 130 ex
 
Wyrmrider said:
use the ported j numbers
you will be close
Click to expand...


Thanks, I did read there wasn't a noticeable difference between the two, mostly a cost difference due to the X being more sought after. I just figured that someone here may have actually had a set checked at some point and I was not being able to find it. My quest continues.
 
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