Intercooler Packaging

[jimk]

Has the fuel pump been sized for max boost?  Take 5 minutes for 

 

[Dudeland]

5 hours ago, jimk said:

Has the fuel pump been sized for max boost?  Take 5 minutes for 

 

Yes the pump will support upto 600 HP.  Dash 6 from front to back, with a high capacity canister filter used for offshore race boats. 

 

[Dudeland]

On 12/23/2022 at 9:08 PM, jimk said:

Not much pump is needed in that circuit.

It isn't so much about volume, rather it is more about longevity.  "Good" pumps that I see are $150 ish. 

 

[jimk]

Will the fuel pump handle the required flow AT the max boost pressure?  That's what the video brings out.  600hp from a boosted engine has different pump requirements than a 600hp NA engine

[Dudeland]

2 hours ago, jimk said:

Will the fuel pump handle the required flow AT the max boost pressure?  That's what the video brings out.  600hp from a boosted engine has different pump requirements than a 600hp NA engine

I see what you mean. Is it able to flow at say 1 bar the same way it would flow at baseline atmospheric, and I would double check, but I think yes. I see the same pumps being used for Turbo LS's sans surge tank.  

[flagoworld]

Do you even need intercooler at 6 psi?

 

I’ve been looking into air to water as well the last few months. Watching this thread now.

 

My biggest challenge right now is due to the choice of radiator I had to use a pusher fan. So intercooler can’t easily sit against rad. Have been considering options. Slotting the lower air dam thing was one thing that ran through my head. But I think sway bar is in the way. Split smaller ones on either side of rad also came to mind. ain both cases air to water seems ideal given the lack of space and not wanting to cut things up.

 

Anyways, for 6psi if you even need an IC, pretty sure it can be very small. Water should be more efficient heat transfer than air I read, so the potentially the front mount could be smaller than if going air to air? But not really sure about that, just some stuff i have read in passing.

[jimk]

Consider this:

Is the 6 psi boost when the car is moving or at a standstill?  Fans aren't needed much even for engine cooling when the car is in motion.  Auto-crossing with a turbo isn't too enjoyable.

 

Engineering deals in mass rate of flow first to do the thermal calculations, then the results are converted to volume rate of flow.  And water heat capacity per unit of mass is 4 times that of air.  So with short bursts of boost, the heat up time for the water is longer than the boost.  The water to air cooler then has time to get rid of the heat when the boost drops off.

 

I wouldn't sweat the "no fan" issue.

Edited December 31, 2022 by jimk

[TobyB]

Quote

Do you even need intercooler at 6 psi?

I remember Corky Bell saying 'no, not really'.  But it's been a loooongggg time 

since I read his book.

 

I do remember lots of efficiency discussion- as in, 6 psi done efficiently won't heat the air

enough to matter, but 6 psi done by a shop air compressor needs to be cooled and de- watered!

(but that might have been a different book)

 

The follow- on question being 'how long are you going to be satisfied with 6 psi?'

of course.

The one I never finished had a hard cut- off at 1 bar.  Because without that, I was pretty

sure I'd end up in the 20's, where piston lifespan was agreed to be measured in minutes

on that engine.

 

t

 

[Dudeland]

On 12/31/2022 at 10:03 AM, jimk said:

Consider this:

Is the 6 psi boost when the car is moving or at a standstill?  Fans aren't needed much even for engine cooling when the car is in motion.  Auto-crossing with a turbo isn't too enjoyable.

 

Engineering deals in mass rate of flow first to do the thermal calculations, then the results are converted to volume rate of flow.  And water heat capacity per unit of mass is 4 times that of air.  So with short bursts of boost, the heat up time for the water is longer than the boost.  The water to air cooler then has time to get rid of the heat when the boost drops off.

 

I wouldn't sweat the "no fan" issue.

I get your question, and the short answer is I don't know.  The 6 PSI would be moving, I suspect that it will build boost by about 3- 3.5K. So first gear at about 20 MPH.

 

From what I can glean is that the fans are used to eliminate heat soak in stop and go traffic.  I live in the heart of the city, so that is a big issue, so fans are likely. 

 

In terms of location, I am eyeballing the opening in the front spoiler of my turbo style spoiler.   The radiator is 7" so perhaps I will have to lay it back to get decent clearance. 

 

It is interesting that the "pulse" of heat for lack of a better term can be accommodated with the water intercooler due to the mass of the water being more efficient to absorb heat. 

 

On 12/31/2022 at 12:30 PM, TobyB said:

The follow- on question being 'how long are you going to be satisfied with 6 psi?'

of course.

The one I never finished had a hard cut- off at 1 bar.  Because without that, I was pretty

sure I'd end up in the 20's, where piston lifespan was agreed to be measured in minutes

on that engine.

 

 

 

The answer to your question is 6PSI.. not long.  But I want to ease into it.  I am in completely untested and unknown territory.  If I run the MS system, then I can monitor exhaust gas temps of each cyl through via a canbus temp sensor array.  Also I can run multiple knock sensors, I can put some safeguards in place.  

 

Using the Sniper EFI  by the time something gets hot, it is too late.  There are zero safeguards.  The only thing I have is a MAP sensor to cut spark if the boost gets too high, but it is likely that it won't react fast enough in an overboost situation. 

 

I would like to run it to make sure that the header, exhaust, oiling and heat management work before I go and build an engine and invest 60-70 hrs in installing and tuning the MS system. 

 

In addition I would like to have time to get the bugs worked out with the RX8 Transmission as well. 

 

In about a week or so I will get wrenching on it.  It has been so long since I turned a wrench, I am unable to really tell how long it will take to do the fenders and upgrades to the fuel system.   The stretch is to get the transmission swapped out and the newly redone sport seats in it. 

 

I am toying with shooting some videos, but I am a noob when it comes to that. 

 

P.S sorry for the late reply.