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-   -   We hurt the 496.... (https://www.offshoreonly.com/forums/general-q/383381-we-hurt-496-a.html)

underpsi68 09-04-2024 05:45 AM


Originally Posted by Ryanw10 (Post 4907802)
Shouldn't the return line be sized bigger than the feed line?

It doesn't need to be bigger. I usually run it 1 size smaller. Nothing wrong running the same size though.

Brad Christy 09-09-2024 08:52 AM


Originally Posted by Ryanw10 (Post 4907802)
Shouldn't the return line be sized bigger than the feed line?

Ryan,

Just thinking logically (as opposed to empirically), I'd have to think there is less fuel flowing through the return line than the feed line. This would indicate to my layman's lizard brain that the return line wouldn't have to be as big as the feed line.

But this is why I'm here asking questions. I don't want my lizard brain to farq this thing up.

Thanks. Brad.

Brad Christy 09-09-2024 09:05 AM


Originally Posted by Rookie (Post 4907762)
There was a lot of discussion in my EFI thread about Y's and T's and they talked me out of them. This is what I ended up with. Probably wont work for your application.
I'd stick with -8.
https://cimg7.ibsrv.net/gimg/www.off...d75c6d4f90.jpg

Rookie,

I'm not sure why the Ys and Ts would be an issue, but I certainly don't want to build in any inherent problems. I'm going to be meeting the builder that is doing the work this afternoon to discuss details of the build, and this is among the topics we will cover. He is aware of my interest in building this fuel rail.

I could potentially configure my rail something similar to yours, but flipped front to back, with the feed and return lines coming in from the front of the engine instead of the back; feed on the port side, return on the starboard (reasons) and the connector on the back of the engine. It would actually mean shorter lines from the pump to the cooler/tank. Any issue with doing that?

Thanks. Brad.

Wildman_grafix 09-09-2024 09:50 AM

I am trying to think also why would the return be larger?


Originally Posted by Brad Christy (Post 4908268)
Ryan,

Just thinking logically (as opposed to empirically), I'd have to think there is less fuel flowing through the return line than the feed line. This would indicate to my layman's lizard brain that the return line wouldn't have to be as big as the feed line.

But this is why I'm here asking questions. I don't want my lizard brain to farq this thing up.

Thanks. Brad.


Brad Christy 09-09-2024 10:54 AM


Originally Posted by compedgemarine (Post 4907799)
would probably be better to cut them for an O-ring fitting as the pipe thread could split the aluminum rail as the ends would not be very thick. I am not a machinest so that is just a guess.

CompedEdge,

You are very likely correct.

I will be welding AN male fittings to the ends of each of the two rails. The entire construction is going to be stainless; 316 seamless tubing and 304 fittings. Rigging fittings will have to be female.

Trying to develop as much of a "drop-in" replacement as I can from my wheelhouse, the two separate rails will be different, having to deal with the coolant reservoir tank and the offset of the cylinders. One will be a bit longer than the other, and have an angled end to accommodate the coolant reservoir. I'll post an AutoCad screen grab of the basic idea shortly.

Thanks. Brad.

Wildman_grafix 09-09-2024 11:05 AM

Hey Brad as a salt water boater just to let you know 304 will rust in salt air. Just in case you want a larger customer base.


Originally Posted by Brad Christy (Post 4908280)
CompedEdge,

You are very likely correct.

I will be welding AN male fittings to the ends of each of the two rails. The entire construction is going to be stainless; 316 seamless tubing and 304 fittings. Rigging fittings will have to be female.

Trying to develop as much of a "drop-in" replacement as I can from my wheelhouse, the two separate rails will be different, having to deal with the coolant reservoir tank and the offset of the cylinders. One will be a bit longer than the other, and have an angled end to accommodate the coolant reservoir. I'll post an AutoCad screen grab of the basic idea shortly.

Thanks. Brad.

Thanks. Brad.


Tartilla 09-09-2024 11:16 AM


Originally Posted by Wildman_grafix (Post 4908277)
I am trying to think also why would the return be larger?

Just a factor: the return line is unpressureized after the regulator.

Similar to the concept of a remote fuel pump feed hose needs to be larger than what the pressurized fluid post pump would require. Unless there is an in tank lift pump to feed the main pump.
​​​


DRAG 09-09-2024 11:37 AM

Only commenting on the rods because I don't know much about the rest of these particular engines, but I know a lot about rods.

Most H-beam rods of all brands are Chinese rods that are pretty inexpensive, and I could tell you the factory that most come out of. They are fine, they work, they are entry level and prices as such. I'm not sure why they have been such a staple and go to in the V8 world for so long, but I think they hold up well in lower rpm NA applications....low boost applications, etc.. In higher end motorsports engines, we don't use H-beam rods. They simply won't last, even in something like 300m we will see the H start to twist and eventually fail, so we run I-beam rods of higher in various materials and we can put them through a LOT more abuse.

Here is one of the strongest steel rods that you can put into an engine. Relatively Inexpensive, and yes also made overseas. I put 300-400hp per cylinder through these things and its hard to hurt one. This is what I'll rebuild my engines with when the time comes. I've put them in hundreds of engines.
Home | Boostline Connecting Rods (boostlineproducts.com)

Brad Christy 09-09-2024 12:50 PM


Originally Posted by Wildman_grafix (Post 4908282)
Hey Brad as a salt water boater just to let you know 304 will rust in salt air. Just in case you want a larger customer base.

Wildman,

I’m aware that 304 is less corrosion resistant than 316, but I have yet to find 316 AN weld-on fittings. I could make them, but that’s a PITA. Something to chew on.

Thanks. Brad.

Brad Christy 09-09-2024 03:17 PM


Originally Posted by DRAG (Post 4908287)
Only commenting on the rods because I don't know much about the rest of these particular engines, but I know a lot about rods.

Most H-beam rods of all brands are Chinese rods that are pretty inexpensive, and I could tell you the factory that most come out of. They are fine, they work, they are entry level and prices as such. I'm not sure why they have been such a staple and go to in the V8 world for so long, but I think they hold up well in lower rpm NA applications....low boost applications, etc.. In higher end motorsports engines, we don't use H-beam rods. They simply won't last, even in something like 300m we will see the H start to twist and eventually fail, so we run I-beam rods of higher in various materials and we can put them through a LOT more abuse.

Here is one of the strongest steel rods that you can put into an engine. Relatively Inexpensive, and yes also made overseas. I put 300-400hp per cylinder through these things and its hard to hurt one. This is what I'll rebuild my engines with when the time comes. I've put them in hundreds of engines.
Home | Boostline Connecting Rods (boostlineproducts.com)

Drag,

At more than double the cost of Molnar, and more expensive than Oliver, these rods are anything by “inexpensive”. If I were going to blow my budget, I’d just go ahead and get the Olivers. Molnar rods, while indeed forged in China, are not coming out of the same foundry as other rods. Tom uses a specific foundry that follows his exact specs for both metallurgy and tempering (Tom Molnar was the chief metallurgical engineer at Oliver before starting his own company), and are then finished in Michigan. I really like what I’ve read from the various forums I’ve stumbled across (mostly street/drag), and I’m reassured by the builder that they are more than adequate for my application. The Molnar-specific ARP bolts, and the engineering behind them, are just icing on the cake.

Thanks. Brad.


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