They are more likely to crack if modified, but on a large displacement build they will probably crack either way.
Dave
Cast iron intake/exhaust manifold porting??
- Thread starter Turboomni
- Start date
They are more likely to crack if modified, but on a large displacement build they will probably crack either way.
Dave
67Monaco
Old Man with a Hat
67Monaco
Old Man with a Hat
They are going to crack either way, it's inherent in their design. Mine were on a bone stock 440 and they cracked.
65Fury440
Senior Member
Those FAST guys are amazing.
One of the members here has a Fury in a series like that, can't remember who.
One of the members here has a Fury in a series like that, can't remember who.
70bigblockdodge
Old Man with a Hat
Those are some well scienced cars. I thought about aiming my Challenger for the pure stock series but I don't think I have that much patience.
moper
Well-Known Member
- Joined
- Nov 15, 2010
- Messages
- 814
- Reaction score
- 448
Personally, I like the look of manifolds, but if there's a need to make some power, it has to be headers. There is litte return on investment in modifying factory iron anything. It is much more rewarding (read that as power-producing) to modify aftermarket parts to look stock. Obviously that means exhaust manifolds are a hinderance, but to be honest - exhaust manifolds can be dealt with by camshaft design, in order to minimize their "negatives" to power. That's how a 500" B wedge makes 580+hp (based on weight and mph - not dyno magic), and wins its factory stock appearance at Carlisle. The FAST class is put together by those with the means to not worry about cost, and rules are in place to maintain an atmosphere where those guys will always win. So return on investment, or "Value" is very different there.
That is my main concern now and is why I am considering a roller cam . What are your thoughts and or experiences on this concerning exhaust manifolds?
Last edited:
Were your stock logs or HP's ?? So it is correct to assume any cast iron exhaust manifolds ,stock type or HP manifolds will crack?
Hey I understand your frustration with us exhaust manifold weirdos lol. If I could do a back to back on exhaust manifolds and headers I'm sure my buttometer would pick the headers for sure and my Depends would verify it. Headers [nice ones cost some dough] is rather major expense plus the exhaust work involved. So my plan is this since I have extorted only so much to build my engine. Gonna build the bottom end right as well as good heads and an attempt at a good cam [maybe roller]. Tidy up the stock intake and exhaust manifolds and slap on a bigger carb. I may even opt for a wide band exhaust sensor [maybe stereo,one on each pipe] so I can tune it well.. If happy I am done,if not I can easily go to a better intake and or headers later. What ya think 70bigblockdodge?
70bigblockdodge
Old Man with a Hat
I would definitely do some grinding.
All in good fun. I understand I had manifolds on my Challenger for the longest time, they worked. They and the original 383 are tucked away and a abusable 400 and headers in place.
All in good fun. I understand I had manifolds on my Challenger for the longest time, they worked. They and the original 383 are tucked away and a abusable 400 and headers in place.
bajajoaquin
Senior Member
Let me just highlight this part again: "Headers [nice ones cost some dough] is rather major expense plus the exhaust work involved."
Yes. A set of TTI headers, if you get them coated, and figure other associated costs are $1000 or close to it.
This is the "marginal $1000" that I've talked about elsewhere, and it's totally maddening to figure out!
If you're building an engine, and you're determined to do it nicely, but not extravagantly, there are certain things you're going to do: pistons, pins, rings, bearings. Probably some rod/machine work to make sure its nice. Bore your engine, probably. Rebuild your heads with hardened seats, new valves, springs, etc. Machine work. New quality cam and lifters. Dual exhaust. Maybe HP manifolds (if you can get them inexpensively, like I did).
I've decided that 440-Source heads are better than stock, and not much more than getting a good head rebuild, that I'm going to add those in.
So that's my baseline. A hydraulic cam is a hydraulic cam, cost-wise. There are some additional costs to non-stock, but not much. So cam selection is a place where you can make another difference without spending a bunch of money.
But what if you want to have a bit more? That's the "marginal $1000." For about $1000, you can have one of the following: Headers ($800 or so), Roller cam ($1000 or so), stroker kit ($1500 or so). Again, these aren't the prices of these items, these are the costs over choosing a more stock-like option.
Which of those three is the best bet? I just don't know, and it's why I keep driving all of you guys crazy talking about it. I don't have unlimited funds to make my dream engine, but I do have about a thousand bucks over a good quality rebuild to make more power. What would make better power in my idle-5000 RPM range, a 440 with good flat-tappet with headers? Roller , 440, with manifolds? Flat-tappet, manifolds, 505"?
They're all pretty similar in cost, and I don't know how to figure which one is better in the real world for that cost.
67Monaco
Old Man with a Hat
Mine were factory to the car, yes HP. I'll see if I can find the old pics of them but they both cracked in pretty much the same spot on bot sides.
67Monaco
Old Man with a Hat
If you're spending the money on a roller setup or stroker kit, may as well do headers at the same time. Why pay for it, just to have the potential of having horsepower that you paid for robbed by poor flowing logs?
Last edited:
bajajoaquin
Senior Member
Because you’re spending money I don’t have.
If the budget covered just spending $2000 rather than $1000, that would solve it!
If the budget covered just spending $2000 rather than $1000, that would solve it!
You have to consider what the builder is trying to accomplish, if top performance is the goal then a roller cam and headers are a must. Stock appearance means manifolds at the cost of some power. Is it worth building a stroker with HP manifolds vs a standard 440? I think the gains in HP and torque are worth it.
bajajoaquin
Senior Member
Appearance is a minor concern. It's mostly about cost, noise, durability.
I am going to do the bottom end and heads right. Intake and exhaust manifolds and cam are easy access later for improvements compared to engine removal. First things first getting the block to my machinist next week to see if all is well with the block.
It seems to me if you take a stock 440 in this case and do nothing else but stroke it ,the engine will make more torque at a lower rpm than the stock motor. The stock heads and manifold and carb will choke it sooner in rpms because of the bigger displacement. Fine ,if the after market aluminum heads flow more than stock then all I have to do is either upgrade the intake or go to headers or both at a later time to satisfy me. If a different cam so be it. But the bottom end at least is ready to do what I want. I have planned to start with stock rockers.
Last edited:
