John, I've been reading this thread since the start. Just wanted to say you sir are an inspiration to us all, just looking at your accomplishments gives me motivation.

Thank you for your contributions to this forum.

 

Update

Made some progress on the hood vent. Finished reinforcing the hood, and made aluminium ducting between the radiator and the hood.

Me welding some sheets together



After a day of fiddling around it looked like this





All the ducting is bolted on, nothing is welded to the radiator. The hood vent and lower ducting can all be removed in a few minutes without having to remove other stuff.



Looks a bit strange, total stock body with a hood vent. I think the suspension and wheels will make it look more at home

 

It might look wierd, yea, since it's the only thing suggesting there is more than 100 lb/ft of torque under the hood lol

 

i think it looks badass!

 

I'm doing something similar right now on my hood as well. I had a shitty Evo 8 hood vent on mine... awful.

I think, however, you might need to add a lip of some sort to the front of the hole in your hood. Something to create an area of low pressure behind it, sucking air out of the hood. Otherwise, you may be presented with the same problem I was having. It created a high pressure area on both top and underneath, making for no airflow at all.

By the way, what did you use to cut the hole in your hood? I tried using a cutoff wheel on an angle grinder, then tried an air-powered cutoff wheel, then moved on to a reciprocating saw. The latter, I don't recommend

 

this build is amazing, keep up the good work!

 

im with him i like it .. good work man

 

Nice work mate,

not sure if someone mentioned it before, but don't you get trouble with transmission cooling this way?

 

my transmission is also fine.. why shouldn't it be?

 

I used an angle grinder and a holesaw for the corners. Worked fine but make sure you have a disc suitable for cutting aluminium, most aren't. Your idea of the lip makes sense, When figuring out how to do the hood vent I just looked at a lot of pictures of serious racecars and looked at their cooling and venting setups. Not everyone uses a lip, The shape of the hood increases the air velocity which lowers pressure so that should create a pressure difference. I even did some flow analysis. Red is high pressure, blue is low pressure, arrows are the flow direction. Testing speed was 180kmh.


Stock FC




Current situation




With lip




Flow simulation doesn't show a large difference between adding a lip or not, so I'm doubting if I should make one. I'll think about it.


I don't see any problems with transmission temperature. If anything the transmission should see lower temperatures because the temperature underneath the hood is lower. I made 2 openings for cool air to enter the engine bay to supply cool air. If I was the transmission I'd be much more worried about the huge 4-rotor trying to eat me instead of the wimpy piece of aluminium sheet behind it.

 

Hmm... that's interesting. I figured you had done some research. From what I saw, most cars that have functional hood vents actually use one. What happens when you take the speed down to something most people would do on the road. For instance, 100 kph?

Also, keep in mind that the air flow won't just stop right there at the engine.

I think you're right about my cutoff wheel. Works great on steel, chews aluminum up like I was cutting it with my teeth.

 

Eim speitchlis...

 

Did you get any tan for welding without sleeves on your shirt?

Looking good as always!

 

how thick is that aluminum you are using for the hood vent.? I will be doing my shrouds soon but the aluminum i found in my local home depot is super thin.

 

This is awesome, I wish I could do even 1/4 of all the stuff you can do with that shop

 

Man, this looks better every day!

Q: isn't this position of the radiator makes the car light on the nose when putting some kphs on the car?
When you turn the radiator 90 deg. (and the blowers hidden underneath it) it's more in the flow line.
Cuz the blowers don't run that often, they are just an obstruction for the flow now.
But that's just me.
I know it's easy to comment but i don't doubt your skills, that should be clear!

Anyway, I'm just enjoying what you are building mate!
Keep up the good work!

Grtz Dee.

PS note the blue areas become bigger than stock...

 

Wow I'm super exsited to see this done

 

you could do the old school way too, racing beat taped yarn to the car and then turned the camera on and went for a run, it would be fun to do that.

+1 on the trans, my buddy with a 2 rotor PP has gone thru 3 turbo transmissions and a diff... if anything the 4 rotor will be better, less Tq fluctuation and the power band is going to fit the horrid gearing better.

 

Pressures acting on the car are much more equal at lower speeds. Flow direction's don't change a whole lot though. Flow velocity obviously does.

100Km/h:



50Km/h:


I know that the airflow doesn't stop, that wouldn't be good at all, but it can't get into the engine bay, the entire path from where the air enters the holes in the front bumper to the exit point in the front hood is almost completely covered with ducting.


Jup, don't have time for sunbathing because of this build so welding will do


I used 2mm thick 1050A sheet for everything, even the radiator end tanks. Pretty sturdy stuff, lightweight, easy to weld, and conducts heat about 35% better than other aluminium alloys.


Well when looking at the flow simulations you could think that, but in reality I don't think it will do that. Remember that the stock bumper is in front of all that ducting and the radiator, the air inlet holes aren't very huge compared to the entire car. Yes the blue areas are a bit bigger than stock, but I think the blue area above the roof of the car get's a bit smaller. I think turning the radiator 90 degrees will do bad things for cooling temperatures, You want the airflow to be perpendicular to the radiator. Blowers will block some of the air, but that's why I didn't cover the entire radiator with them, the top half of the radiator is unobstructed.


That would be fun!
If I get this engine running the way it should run it will probably eat a transmission or two. I think I'll probably try to figure out a decent transmission for the car when it's up and running. Pneumatically operated close ratio straight cut sequential gearbox would go nice with this engine But that's an entirely different project on it's own.

By the way, quick question for everyone that's reading, I'm figuring out how to do the fuel system on the car, at the moment I'm doubting between a stock fuel tank with a swirl pot in the engine bay (got lot's of room left for one), or a fuel cell in the trunk, any thoughts?

 

Stock tank, you need as much fuel capacity as possible
Especially since its a streetcar.

Colleage of mine built a fiat 600 with gsx-r engine and could not fit anything bigger then a 15liter tank. Driving fun is over real quick..

 

We've got a guy here in the states with a 700 HP 3rotor build. He's running a 3rd gen trans with nitride hardened internals, and it seems to hold up really well... may be able to just get your T2 gears hardened. More likely to chip, but they shouldn't shred as easily... it's hard to say...

 

i would do the stock tank + swirl pot, its less work, less cost, plus its less flammable liquid in the passenger compartment.

 

Or you could just sump your tank and only have 1 fuel pump.

 

I've got the swirl pot in the back with stock tank.

But stock thank is pretty heavy actualy lol.

 

The weight of the tank won't be much of an issue in a streetcar with such a monster under the hood..