JPS Subaru Coupe Available Soon

IaM-Ray posted:

Nardi is nice, but I prefer the thin wheeled model.  

Hey Troy I have never heard of a N/A subie doing more than around 220hp with a DOHC are those numbers correct? 

One of our builders who races here says the SOHC give max 185-200hp any thing more is inflated but DOHC gives more.  Just saying 

I think I said estimated 200 to 250hp.  It hasn't been on the dyno so I'm just going by what I've been reading.  I'll tone it down to estimated 200 to 225hp. 

Troy Sloan posted:
IaM-Ray posted:

Nardi is nice, but I prefer the thin wheeled model.  

Hey Troy I have never heard of a N/A subie doing more than around 220hp with a DOHC are those numbers correct? 

One of our builders who races here says the SOHC give max 185-200hp any thing more is inflated but DOHC gives more.  Just saying 

I think I said estimated 200 to 250hp.  It hasn't been on the dyno so I'm just going by what I've been reading.  I'll tone it down to estimated 200 to 225hp. 

FYI, I called Outback's owner and my guy nearby when I was considering creating a more powerful N/A car and both of them were on that page so your new numbers appear more in line I think,   but what do I know  

David Stroud posted:

It would be nice to see how the rad is situated under the front if you care to share.

I would like to see this, only because I have to figure out how I am going to mount the radiator in my coupe.  Speaking of, if anybody has any photos of the radiator mounted in their 356, I would like very much to see those photos.  If the later request is too off topic, please feel free to post any comment or photos in the, "Newbie with a Lot of Questions", thread.

Todd M posted:
David Stroud posted:

It would be nice to see how the rad is situated under the front if you care to share.

I would like to see this, only because I have to figure out how I am going to mount the radiator in my coupe.  Speaking of, if anybody has any photos of the radiator mounted in their 356, I would like very much to see those photos.  If the later request is too off topic, please feel free to post any comment or photos in the, "Newbie with a Lot of Questions", thread.

I'll see what I can do, but it may not happen today, because it's raining.

Troy Sloan posted:
Todd M posted:
David Stroud posted:

It would be nice to see how the rad is situated under the front if you care to share.

I would like to see this, only because I have to figure out how I am going to mount the radiator in my coupe.  Speaking of, if anybody has any photos of the radiator mounted in their 356, I would like very much to see those photos.  If the later request is too off topic, please feel free to post any comment or photos in the, "Newbie with a Lot of Questions", thread.

I'll see what I can do, but it may not happen today, because it's raining.

Yeah, it is.  I have lived in So Cal my whole life, and this is about as much rain I have ever seen in one year.

Troy Sloan posted:

Actually, the AC condenser is what you see in the pictures from underneath, it's attached directly to the radiator and you can see the fans on top of the radiator in the side picture. 

Thanks for those excellent pics, Troy !  They confirm my thoughts that an almost horizontal rad in the front is a very viable way to go and preserves some valuable trunk space that otherwise gets compromised with a vertical rad. Even the hose configuration shown here is similar to mine in the Speedster. 

I put a "shroud/scoop" underneath mine to feed air to the rad and perhaps that wasn't even necessary but it did also keep road debris ( and I've hit lots of it ) away from the rad. I've contended that a horizontal rad will always radiate heat into "clean air" ( cool air ) whereas a vertical rad radiates heat straight up into more radiated hot air to some extent while the car is standing still and the fan has not yet switched on. 

If I do another Soob conversion...and it's likely, my rad will again be horizontal. 

IaM-Ray posted:

you could add another auxiliary pump in line that could boost the flow and even keep it running after you stop which I think Jim and others did 

I haven't found an aux pump necessary. Flow doesn't stop when the car does. Ed Ericson pointed out once that pumping water uphill takes some effort but to push it in a more horizontal direction not so much . 

I may be misinterpreting David's post above, and, if so, my apologies.  If not, I disagree that water keeps moving after engine shutdown.

Automotive water pumps are almost always centrifugal pumps, which take water in at the center of a vane element and fling the water to the outside of the pump housing by centrifugal force as the vanes spin.  Subaru water pumps can put out as much as 52 gpm at 6000 rpm.  However, at idle, the output can drop as low as 2-3 gpm.  They need to be variable, since the cooling requirements at idle differ markedly from WOT, so the design is a compromise between efficient cooling at high speed and not overcooling at startup and idle.  American muscle cars frequently change the pulley size on the water pump to gain rpm if the engine application is hard to cool.

When the vanes stop turning at shutoff, water movement effectively stops.  Bernoulli principle, as I understand it, does allow for pressure differentials in closed systems, which may mandate a slight flow, but those differentials quickly equalize with the pump off.  Within a few seconds, the system has equalized.

The pressure differential required to pump water uphill can be significant, but only for substantial height differences.  In our replicas, we are only talking 1 foot maximum between pump height and the highest point of water circulation, or .43 psi difference, a minor factor.  You lose more pressure with hard plumbing bends than height difference.

I may have misunderstood the above post, or I may learn something new if folks chime in, but the above is standard hydraulics as I learned it 50 years ago.

Jim Kelly posted:

I may be misinterpreting David's post above, and, if so, my apologies.  If not, I disagree that water keeps moving after engine shutdown.

Automotive water pumps are almost always centrifugal pumps, which take water in at the center of a vane element and fling the water to the outside of the pump housing by centrifugal force as the vanes spin.  Subaru water pumps can put out as much as 52 gpm at 6000 rpm.  However, at idle, the output can drop as low as 2-3 gpm.  They need to be variable, since the cooling requirements at idle differ markedly from WOT, so the design is a compromise between efficient cooling at high speed and not overcooling at startup and idle.  American muscle cars frequently change the pulley size on the water pump to gain rpm if the engine application is hard to cool.

When the vanes stop turning at shutoff, water movement effectively stops.  Bernoulli principle, as I understand it, does allow for pressure differentials in closed systems, which may mandate a slight flow, but those differentials quickly equalize with the pump off.  Within a few seconds, the system has equalized.

The pressure differential required to pump water uphill can be significant, but only for substantial height differences.  In our replicas, we are only talking 1 foot maximum between pump height and the highest point of water circulation, or .43 psi difference, a minor factor.  You lose more pressure with hard plumbing bends than height difference.

I may have misunderstood the above post, or I may learn something new if folks chime in, but the above is standard hydraulics as I learned it 50 years ago.

Excellent info as usual, Jim. I was just following Ray's statement but could have said it more clearly. My second sentence above should have said " flow doesn't stop when the car does ....like at idle at a red light " . I didn't mean to infer after engine shutdown but I can see that it may have read like that. In fact, now that I re-read Ray's post, maybe he did mean after engine shutdown. 

When your doing 75mph usually the wind keeps it cool and if not the fans and the water pump circulation keeps it in the operating range.  

The key IMO is what is the plumbing, pump and fans doing to the temperature of the coolant especially when your at idle in extreme heat.  I believe that was the initial issues in a lot of builds and where some builders added auxiliary pumps. 

FYI, I have one that kicks in at idle but I may have one of the more complex systems with dual rads.  It does give me an advantage of a huge gas tanks and trunk... just saying. 

 

Jimmy V. posted:

Where is the radiator mounted on the JPS Coup? Is the roll bar attached to the pan and frame? If I could figure a way to buy the car I would. Guess I will have to be happy with my Suby powered  Speedster. 

 

The roll bar is not attached to the frame, so it would not be race approved, but I believe that it would provide at least some additional protection over none at all and it sure looks COOL! 

IaM-Ray posted:

When your doing 75mph usually the wind keeps it cool and if not the fans and the water pump circulation keeps it in the operating range.  

The key IMO is what is the plumbing, pump and fans doing to the temperature of the coolant especially when your at idle in extreme heat.  I believe that was the initial issues in a lot of builds and where some builders added auxiliary pumps. 

FYI, I have one that kicks in at idle but I may have one of the more complex systems with dual rads.  It does give me an advantage of a huge gas tanks and trunk... just saying. 

 

You have dual radiators?  Why?  And where are they located?

Bill Prout posted:

Better than a Ghia!

Well, i had one and I like them a lot but if you don't have one or the other and you can get a 356 fiberglass body you could save big time on the body work portion of the restoration. That and the no rust in the future is a big plus.  

Did I mention that the 356 shape is time less and the Ghia is ... well a Ghia.  No offence to the rice cooker owner who is redoing a Ghia  

It does not look like P copyrighted the shape of the car hence they have not yet stopped any manu from building any cars only badging.  There must be something out there protecting the manu from getting pursued or is it simply moral or reasonableness that is prevading.  You don't see any 190SL or 300Sl being produced any longer as replicas. 

Just saying.   Anyone know any more?

Troy Sloan posted:

Kirk told me that the Porsche suits visited him in his shop and said he could produce the cars, but could not put any of the Porsche trademarked emblems on them.

And that's fair right?

But if there's no copyrighted logos on the car and no Porsche name in the descriptions (even Porsche replica) than I don't see why ebay is so compliant in cases where there are no infringements.

@WNGD

WNGD posted:
Troy Sloan posted:

Kirk told me that the Porsche suits visited him in his shop and said he could produce the cars, but could not put any of the Porsche trademarked emblems on them.

And that's fair right?

But if there's no copyrighted logos on the car and no Porsche name in the descriptions (even Porsche replica) than I don't see why ebay is so compliant in cases where there are no infringements.

thatโ€™s what I thought. Troy post should not have been taken down. 

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