The next wind tunnel session- suggestions

[BRAAP]

Hey guys, thought I’d finally chime in, better late than never right? ...............

 

Phil,

VERY nice work. Thank you for the contribution here.

How long have you been running it boxed in like that? Any other aero mods to the car that you'd be willing share

 

BTW, that cylinder head looks familiar. A custom N-42 perhaps?

[preith]

Phil,

VERY nice work. Thank you for the contribution here.

How long have you been running it boxed in like that? Any other aero mods to the car that you'd be willing share

 

BTW, that cylinder head looks familiar. A custom N-42 perhaps?

 

Hey Paul,

 

All the compliments, thanks again! The boxed radiator and "sans braces" fenders are it for the aero mods, honest. I've been running the car "boxed" since day one, but this is the 2nd version; a bit more refined as I'm getting more anal as the years progress. The N42 head is actually Rusch version Mrk1, but no matter, still the fastest Z of the bunch. Due to many reasons I haven't had a chance to run the welded head yet, probably towards the end of this year, possibly at Road America.

[Kennysgreen280zt]

What are the thoughts on running the cowl panel soild, rather than having it vented like stock?

 

The vents here, cowl panel is the best term I could come up with.

 

[BRAAP]

What are the thoughts on running the cowl panel soild, rather than having it vented like stock?

 

The vents here, cowl panel is the best term I could come up with.

 

 

 

 

For a street car, I think that would be bad. That is where the “fresh” cabin air comes from.

 

I’ve often thought about ducting the V-8 intake air into that cowl space as picture below, for a couple reasons. One being it is supposed to be a high pressure region, i.e. natural supercharging at speed. Though I don’t think it will yield much more power, or enough that we’d ever notice, but it would be a source for cleaner air, and for those of us that like the sound of the induction system, we would get that more of that as well.

 

[NuttyforNissan]

Ok what if you plate off the whole under body from the radiator with an inch clearance from the floor pan to allow all the air from under the hood to leave at the rear of the car, this is a low pressure zone, is that legal? didn't realize you had restrictions on you.

[OlderThanMe]

.

 

I’ve often thought about ducting the V-8 intake air into that cowl space as picture below, for a couple reasons. One being it is supposed to be a high pressure region, i.e. natural supercharging at speed. Though I don’t think it will yield much more power, or enough that we’d ever notice, but it would be a source for cleaner air, and for those of us that like the sound of the induction system, we would get that more of that as well.

 

It sounds like a good idea...what about your heating/AC blower fan? I would think that the engine would be pulling such a vacuum that it would make the fan strain(as if it doesn't already). Unless you blocked it off from the most of the cowl vents.

[e_racer1999]

another suggestion: how about rear window louvres?

[JMortensen]

another suggestion: how about rear window louvres?

I don't want to speak for those doing the testing, but it seems that we're after racing modifications, and I don't think louvres would even be allowed in any organized racing class just because of the danger they could pose in an accident.

[e_racer1999]

ahh... makes sense. i had just figured that they would have a similar effect as vortex generators, but with the liability of them in an accident i suppose that counts them out

[DCZ]

I don't want to speak for those doing the testing, but it seems that we're after racing modifications, and I don't think louvres would even be allowed in any organized racing class just because of the danger they could pose in an accident.

 

Properly attached, I don't see how they would be any more dangerous than, say, a rear wing. I think louvers look ugly but I like the way they keep the interior cooler and it would be interesting to see if they have an aerodynamic effect.

[zgeezer]

Test the cowl induction hood if possible. I have a brand new one hangining in my garage but shipping would be a real PITA.

 

I'd like to see the effect of a really big hole in the center of the hood as Datsun did with the '73 competition hood scoop, which we all know to be a cover for a very large rectangle cut into the hood. I have one, I'd lend for a test. You'd need to come up with the hood. I expect to close up the radiator intake and use this hood on my 240.

 

 

g

[preith]

Hey guys, I finally had a chance to fab up the oil cooler vane that I spoke of earlier. I think it will work well.

 

[Guest TeamNissan]

Wow preith that looks pretty good man. I hope when I finish mine it looks that good lol.

 

On a side note. I was thinking of closing off the front like you only butting a somewhat small ic to it, sealing the tiny space off. Then a duct from the back of the ic to the rad. Does anyone think that will cause any air flow probs with the front of the car?

[jknc90]

I'd like to see the effect of a really big hole in the center of the hood as Datsun did with the '73 competition hood scoop, which we all know to be a cover for a very large rectangle cut into the hood. I have one, I'd lend for a test. You'd need to come up with the hood. I expect to close up the radiator intake and use this hood on my 240.

g

 

I have a hood with the competition hood vent fiberglassed and bolted on. I'm cleaning up some of the fg work the PO did and then using it on my car when I'm finished. I'd really like to see it tested next round.

 

Jon

[JMortensen]

Wow preith that looks pretty good man. I hope when I finish mine it looks that good lol.

 

On a side note. I was thinking of closing off the front like you only butting a somewhat small ic to it, sealing the tiny space off. Then a duct from the back of the ic to the rad. Does anyone think that will cause any air flow probs with the front of the car?

Get a bigger intercooler and seal the gap from the intercooler to the radiator. Then seal the openings between the airdam and the core support. You don't want a small intercooler, and I really feel that most guys have them sitting in the fairly stagnant air with little to no flow through the fins. If you butt the two up against each other then the air will flow through both the intercooler and the radiator. Despite the radiator being "hot" the vastly increased airflow should mean lower charge temps, at least that's my theory...

[Guest TeamNissan]

Thank you for the heads up J. Do you think it would be better to duct the small opening to the ic butted and sealed to the rad? Like a reverse funnel or just enclose it all like preith I guess is the question.

[JMortensen]

Either way. IF you did the smaller duct like preith has then the air that gets into that duct HAS to go through the intercooler. If you seal the intercooler to the rad then the air that enters the intercooler HAS to go through the radiator. Probably best would be a combination of both, where the intercooler had its own duct to the front and was also sealed to the radiator.

 

I haven't seen anyone address it yet, but it's also a good idea to put weatherstrips between the core support and the radiator so that the air can't squeeze through that gap either.

[Guest TeamNissan]

Thnx again j.

 

Actually Joe (rags) sealed his rad to the core support. He will have to pics though.

[e_racer1999]

in regards to sealing up the radiator area: would brake ducts (since they would have lower pressure than the dead radiator spot) actually increase the flow of air under the car?

[JMortensen]

in regards to sealing up the radiator area: would brake ducts (since they would have lower pressure than the dead radiator spot) actually increase the flow of air under the car?

Yes an airdam with holes for brake ducts would allow more air under the car. If they were actually ducted to the brakes the idea is that the air would hopefully go through the wheel and out past the side of the car.