2G FWD Aero Questions/Concerns

[orangedsm]

I've been reading through Andrew Brilliant's posts, and there's lots of great info, but most of the pictures are gone. I don't want to go quite as high-end as he did of course, I'm an IT person, not an aerodynamics expert. I'll consider pro CFD eventually, but want to DIY for now.

I'm not going to be RACING in any particular series, this is mostly for fun, open track days around the Pacific Northwest and California.

I have a decent understanding of open-wheel aero from my days many years ago racing Formula Ford and Formula Continental, but closed-wheel aero is a whole new thing to me because of all the limitations.

I would like to emulate the aero build of something like the Spoon FD2 Civic. I'll be running moderate power levels (Evo III 16g), fender flares, 285's currently (will drop to 275's probably next set of tires).

Does anyone have pictures of a full flat floor on a 2g GST?

I'm thinking for the rear to do a partial cutout of the OEM rear bumper, cut out the spare tire well, install a full diffuser, and have the exhaust exit higher up, just above the diffuser, in the center (around where the factory license plate goes). Can anyone see any potential issues with running a setup like that?

I know dumping the exhaust before that would be better, but for the next few years it's not going to be a full track car, will be driven occasionally on the street. So I'd like to keep a muffled exhaust for now. I can't see any routing issues coming up since I'm FWD. Thoughts?

Thanks!

 

[1998_gst]

Found your post, I am also interested in aero on a fwd. Mostly the rear end/ bumper vents or partial cut out. Have you found anything?

I've been reading through Andrew Brilliant's posts, and there's lots of great info, but most of the pictures are gone. I don't want to go quite as high-end as he did of course, I'm an IT person, not an aerodynamics expert. I'll consider pro CFD eventually, but want to DIY for now.

I'm not going to be RACING in any particular series, this is mostly for fun, open track days around the Pacific Northwest and California.

I have a decent understanding of open-wheel aero from my days many years ago racing Formula Ford and Formula Continental, but closed-wheel aero is a whole new thing to me because of all the limitations.

I would like to emulate the aero build of something like the Spoon FD2 Civic. I'll be running moderate power levels (Evo III 16g), fender flares, 285's currently (will drop to 275's probably next set of tires).

Does anyone have pictures of a full flat floor on a 2g GST?

I'm thinking for the rear to do a partial cutout of the OEM rear bumper, cut out the spare tire well, install a full diffuser, and have the exhaust exit higher up, just above the diffuser, in the center (around where the factory license plate goes). Can anyone see any potential issues with running a setup like that?

I know dumping the exhaust before that would be better, but for the next few years it's not going to be a full track car, will be driven occasionally on the street. So I'd like to keep a muffled exhaust for now. I can't see any routing issues coming up since I'm FWD. Thoughts?

Thanks!

I've been reading through Andrew Brilliant's posts, and there's lots of great info, but most of the pictures are gone. I don't want to go quite as high-end as he did of course, I'm an IT person, not an aerodynamics expert. I'll consider pro CFD eventually, but want to DIY for now.

I'm not going to be RACING in any particular series, this is mostly for fun, open track days around the Pacific Northwest and California.

I have a decent understanding of open-wheel aero from my days many years ago racing Formula Ford and Formula Continental, but closed-wheel aero is a whole new thing to me because of all the limitations.

I would like to emulate the aero build of something like the Spoon FD2 Civic. I'll be running moderate power levels (Evo III 16g), fender flares, 285's currently (will drop to 275's probably next set of tires).

Does anyone have pictures of a full flat floor on a 2g GST?

I'm thinking for the rear to do a partial cutout of the OEM rear bumper, cut out the spare tire well, install a full diffuser, and have the exhaust exit higher up, just above the diffuser, in the center (around where the factory license plate goes). Can anyone see any potential issues with running a setup like that?

I know dumping the exhaust before that would be better, but for the next few years it's not going to be a full track car, will be driven occasionally on the street. So I'd like to keep a muffled exhaust for now. I can't see any routing issues coming up since I'm FWD. Thoughts?

Thanks!

 

[EC17PSE]

Well what you describe is pretty much what im doing for Time Attack on my FWD, if you flat floor and join a series they normally put you in the upper most tier or class.

Im making my own aero aswel as its fun to do but also get to follow a huge array of different types of aero.

I re did my exhaust to come out my bumper, i have attached a pic to show its new place,

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[orangedsm]

Well what you describe is pretty much what im doing for Time Attack on my FWD, if you flat floor and join a series they normally put you in the upper most tier or class.

Im making my own aero aswel as its fun to do but also get to follow a huge array of different types of aero.

I re did my exhaust to come out my bumper, i have attached a pic to show its new place,

That looks great!

I've read the different class restrictions for a few different organizations, but I'm not completely concerned with them. I'm doing this more for fun, and won't be actively competing, at least not seriously.

How did you go about doing your exhaust? It appears you cut out the spare tire well, is that true? I'm considering removing the stock fuel tank as well and going to a fuel cell. Would be able to run the exhaust straight back and through.

 

[EC17PSE]

That looks great!

I've read the different class restrictions for a few different organizations, but I'm not completely concerned with them. I'm doing this more for fun, and won't be actively competing, at least not seriously.

How did you go about doing your exhaust? It appears you cut out the spare tire well, is that true? I'm considering removing the stock fuel tank as well and going to a fuel cell. Would be able to run the exhaust straight back and through.

If your not limited by a class because of not competing then your good to do anything. Not having done it before i dont know how bad it is to do on our cars but do know that any work needed to be done takes alot longer because you have to remove everything and can take hours depending on alot of things so i been told by a few teams with flat floors,

Yes my tire well has been removed and my rear bumper bar has gone aswel, my fuel tank is still there currently but thats next to be made as then i can go under the tank add get rid of the couple of bends that go around the stock tank

 

[orangedsm]

If your not limited by a class because of not competing then your good to do anything. Not having done it before i dont know how bad it is to do on our cars but do know that any work needed to be done takes alot longer because you have to remove everything and can take hours depending on alot of things so i been told by a few teams with flat floors,

Yes my tire well has been removed and my rear bumper bar has gone aswel, my fuel tank is still there currently but thats next to be made as then i can go under the tank add get rid of the couple of bends that go around the stock tank

Thanks for the information.

I'm curious, what is the red thing directly below your exhaust, tow strap? What about the two black pieces on either side of the exhaust, tow hooks?

 

[EC17PSE]

Thanks for the information.

I'm curious, what is the red thing directly below your exhaust, tow strap? What about the two black pieces on either side of the exhaust, tow hooks?

so as you know we dont have any tow mounting places so I made a sub brace using the oem rear bumper mounting holes which allow me to have a tow strap and them bits at the side are for my aerofoil mountings, I decided to have the mounts low rather coming from the trunk since i dont want water to get in the holes as it still gets used on the roads and is road legal still, while i was going to use these I have decided to now switch to tube steel instead for strength and more rigidity strength both sideways and vertical force so no bowing of my alloy plate I previously made, pic to show what it looks like mounted

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