Head flow and power differences question / discussion

-
If it was me I would have them pressure tested, flow tested, vacuum tested and valve job checked out, new valve seals, set up for your cam and go have fun.
 
Well they were supposedly just refreshed by Indy less than 10 passes before being removed.
Should I still have that done? The boxes they are in are from Indy and they look great.
If it was me I would have them pressure tested, flow tested, vacuum tested and valve job checked out, new valve seals, set up for your cam and go have fun.
My builder will set them up for the cam I’m sure. He probably has everything to check them out also as he is a highly experienced builder and well know Mopar racer.
I’ll definitely go whichever route he recommends.
I will update as I talk to him about it more.
Thanks for the suggestions. This is the kind of guidance I’m looking for.
 
“Mail Order HorsePower!” Just a click away!

It’s funny that you mention this. As I’ve been posting here, it made me think.

I’ve purchased probably close to 80% of this project from this forum.

If I were to name my engines like the famous racer I read about the other night, it would have to be the FABO engine.

Thanks again to everyone who chimed in.
 
Even if there's a driveability/street performance issue with the Indy heads, is it worth spending $3000+ on the other heads?, If the Indy ain't gonna cost you to give them a try, don't know why not do that 1st, could always swap heads later or spend that on a gears & gear vendor od or something else more fun.
 
It’s funny that you mention this. As I’ve been posting here, it made me think.

I’ve purchased probably close to 80% of this project from this forum.

If I were to name my engines like the famous racer I read about the other night, it would have to be the FABO engine.

Thanks again to everyone who chimed in.

Funny! I purchase a lot from here as well.

I gotta go with @pittsburghracer & @273. The Indy heads are otherwise ready to rock and roll? They’re just closer to the finish line of having the car ready to run. I’d do it and see how the car is. The worst case scenario is you do a top end head swap next winter?
 
My 360-1 Indy headed engine and my Edelbrock engine have both gone 5.98 with my son driving and 6.0 many times with me driving. The Indy engine had a .650 solid lifter cam and the Edelbrock headed engine has a .650 racer brown roller cam. Both engines have room to grow cam wise. Both engines will have better heads next year. It’s like baking a cake. It’s all about the right ingredients.
 
We've made just under 580HP with them, using a hyd. roller cam! But they need work, they were not ootb heads at all. Compression was 10.7:1.
We made a touch more than that with ootb ports but the heads themselves were not ootb. I had them disassembled and gone through. A few guides were a little tight.
 
Just an example but my 410 with ootb trickflows made 550hp @5800 and 550tq @4500 with a sft cam and ootb rpm air gap. I am very happy with the trickflows and my engine but if I had the heads you have I would have used them.
 
Just an example but my 410 with ootb trickflows made 550hp @5800 and 550tq @4500 with a sft cam and ootb rpm air gap. I am very happy with the trickflows and my engine but if I had the heads you have I would have used them.
I’ve decided to use the Indy heads, the Trick Flows would allow me to use a six pack setup I have or the tunnel ram easily.
I can mod the tunnel ram for the Indy heads fairly easy but don’t really want to do it for the six pack.

The more I think of the work I put into the spare hood, I am sticking with the tunnel ram.

Thanks for the input.

IMG_8669.jpeg


IMG_8914.jpeg


IMG_8935.jpeg


IMG_9150.jpeg
 
Last edited:
I am curious how much difference does let’s say 30-40 cfm of head flow make in HP.

Example: N/A small block 416 cu. 11.5 / 1 +/- compression

With a set of heads that flow 325 +/- compared to heads that flow 293 +/-

Everything else on the engine would be the same,intake,carb(s), cam,headers,ect.

Will the different heads be noticeable driving on the street or on a dyno only?

(edit)
What I am really trying to find out is, is there such a thing as too much flow and after a certain number, does the power curve go flat ? Or, is it always best to have the highest flowing heads available?

Let me know your thoughts and if I forgot mention anything.

Thanks in advance.
Depends on application. Will this be a mostly hot road engine, a more track oriented engine or something along the lines of engine masters where the dyno rules. Track and dyno would be closer as low RPM response is not a factor. With street use in mind throttle response and lower RPM torque are the major concern. In this cituation the smaller heads are probably a better choice.
Max flow is good for street racing bragging rights (basically playing bullshit poker). What matters is port density and port efficiency, which contribute to cylinder filling. A smaller port contributes to higher airflow speed which helps fill the cylinder after the piston starts coming up on the compression stroke, but before IVC. The larger port contributes to lazy airflow and lower swirl. In a race engine at higher RPMs the larger ports should tend to more power.
 
I did watch this last night.



I get that, but doesn't help with your question, 550 hp and less trick flow all the way, 600 hp plus Indy, 550-600 hp you could use either, 550-575 hp I'd lean trick flow 575-600 hp indy but also is a peak hp rpm of 6500-7000 rpm engine streetable to you ? It might be everyone is different, what about if you run 3.23-3.55 gears?

Trick flow the more streetable choice especially since your not overly concerned about the hp goal as long it's 550 hp or better but you could also just cam and gear it for the indys you got.
Is it worth buying a set of heads over ones you got? could always swap down the road if not happy with the indys.

It's all a series of compromises.
 
Are you saying I should watch this video?
I already have.
 
You could probably sell the Sixpack setup, and finance the trick flows, with a buck or two left over......
But if I HAVE the indy's, and I have to buy less-flowing heads?....... I'm running the indy heads, 100%
 
You could probably sell the Sixpack setup, and finance the trick flows, with a buck or two left over......
But if I HAVE the indy's, and I have to buy less-flowing heads?....... I'm running the indy heads, 100%
Yep, that’s the route I’m thinking about going.
It’s hard to beat the tunnel ram for several reasons and I have the Indy heads already.
Thanks for your input.
 
Yes lol but then I’d have to buy another car for the second engine and I’d have to clean out the other side of the garage for the second car and probably Build a bigger doghouse in the backyard. But I’ll keep your suggestion in mind.
Paint both cars the same color, so you can trick people from day to day.
 
Paint both cars the same color, so you can trick people from day to day.
LMAO. There was a fella up north that would loose a race and say “I’ll race you again for more money if I can go home and put on my headers to whoop yar ***.” He would reappear with an identical car with much more power, take the money and run.
 
I just got the results of this build and I am smiling.
I stuck with the Indy heads and went with Holley 550 tunnel ram carbs custom built from Allstate Carburetor.
Molnar 416 stroker kit (418) from @PROSTOCKTOM.

My builder didn’t beat on the engine, just ran it for break in. Nice weather for the dyno.
Looking forward to getting in the car.

IMG_1615.png


IMG_1616.png


IMG_1614.jpeg


IMG_1612.jpeg
 
Last edited:
The BSFC numbers are what I like to see, as it indicates how efficient the engine is. Yours look like it's doing really well and reflects in your output.

Super nice engine, should be a lot of fun banging through the gears.

What altitude are you at?

Tom
 
Camshaft numbers from the above build? Just looking quickly at the numbers it seems under cammed.
 
Camshaft numbers from the above build? Just looking quickly at the numbers it seems under cammed.
I only have some of the numbers so far. I’m at 5000’ and wanted to keep cyl pressure up so the duration is lower. It’s a solid roller for the street so I wanted it to not be tough on the valve train.
The builder’s cam grinder picked the specs from the info I gave him.
It is a smaller cam but I’m not looking for max power.
I’ll post the specs once I get them all.

I was hoping for 550-600 and am happy with these numbers.

Thanks
 
I only have some of the numbers so far. I’m at 5000’ and wanted to keep cyl pressure up so the duration is lower. It’s a solid roller for the street so I wanted it to not be tough on the valve train.
The builder’s cam grinder picked the specs from the info I gave him.
It is a smaller cam but I’m not looking for max power.
I’ll post the specs once I get them all.

I was hoping for 550-600 and am happy with these numbers.

Thanks
I think it made respectable power, and if you gave the builder some parameters to fit and he did, and you’re happy then it’s a win win!
 
He built a stock stroke 340 for me a few years ago. It has Edelbrock closed chamber heads, with a Holley 650 on an airgap intake. It made 400 Hp / 408 TQ.

It runs great with a tunnel ram, or six pack.

When I came across the Indy heads, I just had to have him build something a little more.

This new one should be fun. I found a new Chris Andrews 904 with custom converter, rmvb and low gear set to replace the 727.
 
It seems to be in the range of the trickflow 190 head builds That's a good build.
Tunnel ram is awesome & a Chris Andrews transmission.... Hell that's good stuff
 
Last edited:
-
Back
Top