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Spacenut
07-12-2010, 10:30 PM
Hi guys - some opinions please.

After a lot of deliberation (and the onset of cold weather!) I have decided not to install A/C in the Green Machine. My reasoning is that my new (old) Mk1 sunroof canopy has a sunroof (duh), and air extractor vents for when its raining and the sunroof is closed.

However, this still leaves the question of how to get airflow into the cockpit, as the sunroof and vents merely allow the air out.

I currently have fresh air intakes either side of the radiator grille. These don't provide a lot of airflow with my current (sealed) canopy. I was thinking of foregoing my glass side windows in favour of tinted Lexan, so I can use those natty little aircraft vents, similar to the ones Jim fitted to Nena. How did these work out for you Jim?

The Ford GT40 had three NACA ducts on the nose - two small ones inboard of the headlights for the dashboard face vents and a single, larger NACA duct in the middle just in front of the windscreen to feed the fresh-air demister plenum.

Green Machine uses an offset windscreen wiper spindle, so I could fit a NACA intake into the canopy moulding just below the windscreen to feed the heater/fresh-air system instead of the nose intakes. The latter can then be turned over to brake cooling.

What do you think? Is the NACA duct worth a shot? Or will I be so pleased with an opening sunroof and aircraft vents that the NACA duct would be an expensive (and aesthetically fussy) mistake? I know it won't work as well as the GT40 for a start - the latter has a more pronounced break between the body and the windscreen line, which results in a high pressure area. I wouldn't be surprised if the airflow over the top of the Nova stays largely laminar all the way...

Anyway, let me know what you think.

Lauren

Big Birds Car
07-12-2010, 11:10 PM
I currently have fresh air intakes either side of the radiator grille. These don't provide a lot of airflow with my current (sealed) canopy.
Shouldn't you wait to see if with the sunroof these provide air flow? Could you not use inline fan units (one in each duct) to help flow when the sunroof is open?

bushboy
08-12-2010, 12:03 AM
Lauren,
Summer time for me is T Tops out along with the side perspex. I really want removable glass & hopefully 2011 will see that come to fruition. However, on the few occasions that I had to endure motoring with the tops in I did get hot, esp when stopped in traffic. I intend (When clam shells permit) to fit inline blowers (boat bilge extractors) in the side pods, to provide cabin ventilation, & a cool breeze. Despite fitting blanking panels behind the front wheels there is still a lot of air pumped into the cabin when the reek is on the move. My side "pockets" have vent holes in them and provide some fresh air once on the move. Due to current poor sealing I am guessing that the cabin air has some where to escape.

I know this does not answer your question, but I think a move from glass to perspex side windows will be a step backwards. I had always intended to use the bonnet nostrils to provide cabin air, but that is still a pipe dream.

Good luck with what ever path you choose to take.

Bushboy

Spacenut
08-12-2010, 12:35 PM
Thanks guys. I would like to wait until I have the sunroof fitted before I make a decision about the nose intakes, but the problem with that is the new canopy will be painted, glass fitted etc. by then, so I wouldn't be inclined to start cutting into the bodywork adding NACA ducts!

Martin, I hear what you say. I would like to keep the side windows glass as well. I just saw some pictures of the Vector W2 in one of its intermediate forms, and the side windows, as well as having removable sections (later converted to sliding windowlettes like the BMW 2002 Turbo) had two pop-out vents on each window as well. Unless anyone else has experience of these, I guess I am waiting for Jim to tell me how well they worked for him in Nena.

There were a couple of advantages to using Lexan - a sheet of bronze tint Lexan it cheaper than the price I was quoted for glass (although that was toughened 5mm bronze tint with obscuration banding), and I would have enough surplus to experiment with windowlettes or removable sections. The downsides were figuring out how to apply obscuration banding to Lexan and suitable bonding techniques (I don't want to use fixing screws).

So its still up in the air at the moment!

(but my stainless canopy hinges are off for modification now, so there is a bit of progress...)

Lauren

hildi25
08-12-2010, 08:31 PM
Hi Lauren, I ran a duct for cockpit air to the depression below the nostril intakes this previous year. I didn't even feel any flow at all (:no fan to create any flow:) , but figured that this would do something. NOPE. Personally I don't use AC like others do. But I have diven with the convertible top on and off. with it off I have always felt comfortable, with it on I want to get out asap. I also made the rear window removable to improve airflow, but never felt this to be necessary. I dropped the rear window tunnel and extended the interior to wherethe gas tank was. I dont know if this helped or was even on subject, but I hope it helped. \

ROB

Big Birds Car
08-12-2010, 10:55 PM
The downsides were figuring out how to apply obscuration banding to Lexan and suitable bonding techniques (I don't want to use fixing screws).


Would the stuff I and Jemp have used for glass not be applicable to lexan? The obscuration looks very clean and tidy and the glass adhesive certainly sticks like the proverbial to a blanket, however I have no experience with lexan.

Dirk
08-12-2010, 11:02 PM
Opening the back window for ventilation air flow is worth a thought, the wife drives an L200 that has a electric back window into the back load space. Mmm but then there is the fuel tank! Or an engine Lauren :wink:

Dirk

Spacenut
09-12-2010, 01:04 PM
Hi Lauren, I ran a duct for cockpit air to the depression below the nostril intakes this previous year. I didn't even feel any flow at all (:no fan to create any flow:) , but figured that this would do something. NOPE. Personally I don't use AC like others do. But I have diven with the convertible top on and off. with it off I have always felt comfortable, with it on I want to get out asap. I also made the rear window removable to improve airflow, but never felt this to be necessary. I dropped the rear window tunnel and extended the interior to wherethe gas tank was. I dont know if this helped or was even on subject, but I hope it helped. \

ROB

Hi Rob - no, that is useful information, thanks for sharing! Your experience tends to confirm that (at the mid-bonnet point at any rate) there is very little positive pressure differential compared to the cockpit, which suggests the flow is laminar at that point. There might be a little bit of positive differential at the base of the windscreen, but the body contours blend so well that I can't imagine there would be any significant disruption to the airflow, which would be required to create a high pressure area. Obviously the windscreen wiper messes things up, but probably not enough.

I took my rear window out completely and drove around for a bit. Lets just say my industrial ear defenders came in handy :D

I was expecting great things, but there was b*gger-all difference in the airflow through the face vents (connected to the nose intakes), although some of the draughts around the canopy sealing line were more apparent, suggesting that if I got my outside air from somewhere else, maybe things would be better.

I may well consider using individual line booster fans for ventilation, as BBC suggested - but first I need to re-design my entire heating/demisting system so that I can isolate the matrix completely from the fresh-air circuit. That's what you get for using an aftermarket heater box I suppose :annoyed:

Lexan seems to be funny stuff - it evolves gas when heated (even in the sun), which causes tinting film to bubble, and presumably reduces the adhesion of certain bonding agents. And any kind of painted banding as well, I assume. So unless those pop-out aircraft vents are really really good (Jim?), I think I am going to stick with glass...

Thanks for all of your thoughts and recommendations so far.

Lauren

PS - rear bearings now replaced, modified stainless canopy hinges due by the end of the week. All being well I will be able to go to the AROC Christmas dinner on Sunday in the Green Machine!

jimcub
09-12-2010, 07:36 PM
I had tinted side windows until they crazed and fell out, I replaced with clear perspex and wow they can be hot in summer. With the sun roof out the sun burns your head, if like me your protection has thinned out with age.
The only through air flow in the cab is when the sunroof is open, this even hepls with demisting but in rain it causes problems even with stock beetle heaters.
Independant air exit in the cab would be good, air in is not a problem due to the number of open spaces around the bodywork; but when the sunroof is shut all air in stops due to restricted means of air getting out.

CyCo
10-12-2010, 01:23 AM
Don't forget fluid dynamics (again, it keeps coming up, doesn't it?). If it comes in, it must be able to go out. If you've got a vent into the cabin from ducting at the front, and the cabin is sealed (ie, no operable windows, sunroof, targa panel, ect), then your air flow is going to be minimal.

Most of the 'reeks here in Oz have removable windows (there are one or two with fixed windows!), plus vents/ducting. A couple are now sporting a/c.

Now my current set up in unique, but should give some food for thought. When Ron was rewiring my car, he made a fiberglass panel that goes over my radiator up front.

Before:

http://i4.photobucket.com/albums/y105/cycoholic/My%20Eureka%20F4/RadiatorBatterySetup.jpg

After:

http://i4.photobucket.com/albums/y105/cycoholic/My%20Eureka%20F4/Eureka013.jpg

He also added ducting to my car, as it didn't have any! But as my car was practically open top, the vents weren't really used anyway. So three vents no work via ducting, the 4th is there for looks. :tongue: He just ran out of ducting.

Now running around with Ron's 'standard' roof, I've noticed if I have the vents open, and one of the windows popped open, I get better air flow than with just the vents open (fluid dynamics). However, I usually don't run with the windows in unless I have too, gets quite warm otherwise.

Now here's the thing. When Ron made that fiberglass panel to go over my radiator, he made a positive pressure area up front. Wether by design or accident, I have no idea, probably the latter. My car has a couple of ashtrays that were there when I bought the car, a couple of those 'D' shaped concealable ones, I have a feeling they came from a Chrysler/Valiant. These just sit snug in their holes, just above where people tent to stick speakers up near their knees in the sides. Also, there are two small squares cut into the side pods on the inside, up near the top. These would have been for the rubber hold downs used to 'lock' the roof in place when the roof was manual however many years ago. They've never been filled in.

But after the addition of the fiberglass panel, when driving at speed I've noticed a fair amount of air being forced out of those tiny square holes. And at freeway speeds, those ashtrays get blown out onto the floor, often ending up some 6" - 8" away from the sidepod!

Obviously some form of air in/out system is needed. Now your system already has extractor vents, you're looking for a better intake system. Hmm, what about an airbox up front, but instead of feeding the engine air, it's feeding the cabin. Would an airbox make a positive pressure area? The airbox gets fed air from the front, and then up to your vents in the cabin. Of course I know you have a custom tank up front, but also you're running a spaceframe, so really only you know if that's an option.

At the very least, try experimenting with some perspex windows. Most of us over here in Oz run removable windows with latches from the rear quarter windows from old Colts/Mazdas. Similar latches can be had of current extended cab utes (Toyota Hilux). The windows normally screw in, and the latch opens the windows several inches for air flow.

http://i4.photobucket.com/albums/y105/cycoholic/My%20Eureka%20F4/20092008004.jpg

http://i4.photobucket.com/albums/y105/cycoholic/My%20Eureka%20F4/20092008005.jpg

Try the windows first, before taking to the fiberglass.

:wink:

islandman
10-12-2010, 03:37 AM
I agree, my opening side windows also really make a big difference to airflow and the level of comfort

*edit - Post moved to this topic by admin*

Spacenut
10-12-2010, 10:23 PM
Thanks Cyco, that's very interesting. Like you, I have paid attention to air extraction, although I have been reluctant to take a holesaw to my canopy. What I did instead was fit a pair of spare cheesegrater vents (Escort Mk1) in the rear bulkhead either side of the seats. They vent into the rear wheelarch area, but have never been that effective - perhaps there is too much positive pressure in the wheelarches.

The nose intakes connect to a pair of 2" squeegy pipes which run along the inside of the front wheelarches before running inboard under the fuel tank and connect to a pair of ports in the centre of the front bulkhead. There is an airbox behind the bulkhead, which is actually a partitioned-off part of the centre tunnel. Its done with cardboard and gaffer tape so I think I am losing a lot of airflow to leaks. The heater box fan is boxed-in over the top of the airbox. There are two outlet ports in front of the heater matrix, and two behind. The two in front are connected to the face vents through some more squeegy pipe. The two outlets behind the matrix produce heated air, and are ducted up to the demister vents.

My face vents are therefore connected, in a convoluted way, directly to the nose intakes, so I was expecting better "ram-air" effect than I currently get. But I suppose it is all down to how I am extracting the air from the cabin.

Nova Nigel had a Mk1 sunroof canopy like the one I have for the Green Machine (not fitted yet), and that had functioning extractor vents in the canopy roof, either side of the T-handle depression. Nigel reports that they helped with side window demisting even though he did not have a functioning heater (no heat exchangers on his Vo-Po engine). So I am hoping that the extractor vents on top of the canopy will work better than my bulkhead items. And obviously when it isn't raining I can remove the sunroof panel altogether (or maybe even fit a tilt mechanism, like Alex has).

I wasn't sold on the idea of a NACA duct, so you've convinced me not to go down that route now.

Lauren

Vasco Da Gamer
11-12-2010, 11:13 AM
I am glad you are not going down the extra NACA duct rout, I think it would have been very difficult to come up with something that looked right where you were considering - although you have proved you can do it with the bonnet nostril conversion.

My reason for posting is to ask how effective people have found the leak-proofing on "catched" glass side windows, I was hoping to go that way myself but have seen several posts mentioning the difficulty of getting flat glass to fit MK1 canopies (maybe all canopies). It seems to me the most effective and least style-b*gger*ng route is indeed opening side windows and sunroof (neither of which I have yet), but all of us living in the UK have to pay careful attention to the rain problem of course.

I liked the idea of vents into the back wheelarches - pity that didn't work, perhaps yet more ducting from them to the rear of the car would make a difference.

Regards from Steve

Alzax3
11-12-2010, 06:22 PM
Even with my patent drip-chanel canopy restyling, the seals aren't one hundred percent, they always get tested coming home from Stones as it always p****s down then for some reason......Mind, saying that, the Corsa doesn't always seal perfectly either........

Vasco Da Gamer
12-12-2010, 01:22 AM
:D That's what I thought..... Must be subtle restyling, I haven't noticed it in the pictures of your car.

Really must get to more shows next year; working car or not - so I can look at this kind of detailing.

CyCo
12-12-2010, 02:31 AM
The side windows on my 'reek are 3mm perspex, fitted with a piece of 's' profile extruded rubber that goes along the leading edge and top of the window opening. First this rubber strip is fitted, then fit the window in place with a couple of screws (or bolts if that's your fancy). Don't tighten the screws up, as you have to get the perspex into the groove in the rubber strip. A standard screwdriver helps. A combination of pushing the window up and the screwdriver will get the window fitted, and then tighten off those two screws. Then screw the latch in place on the inside of the rood and your done. Takes way too long at around 20-30 minutes.

However, on the way back from our meet this year (I'll get around to uploading photos one day, lol), it was raining fairly hard for most of the first half of of the trip. And it was really the first time the side windows had been used in heavy rain. And I was most pleased with their performance! It did leak, but only at the very front and rear of the windows. The leak at the front didn't bother us, as it just leaked onto the sidepod and out of the car, and the rear leak was very minor. We use electrical tape to help with leaking windows over here, but I think that I could have used much less than what I'd 'normally' use.

In short, despite some heavy rain, we were warm and dry.

:)

Spacenut
12-12-2010, 08:21 PM
:D That's what I thought..... Must be subtle restyling, I haven't noticed it in the pictures of your car.

Really must get to more shows next year; working car or not - so I can look at this kind of detailing.

Hi Steve - yes, Alex's modification is subtle. I'm surprised to hear it is not 100% effective, but there again, its subtlety lies in the fact that it is more of a drip deflector than a drip channel. But it did get me thinking about one aspect of Nova styling that trumpets the fact that the side windows don't open - they are flush with the sides of the canopy.

Now, this is clearly good from an aerodynamic standpoint, and explains why there is no wind noise (that I can hear above the sound of the engine that is) on the move, but it confirms to all the windows cannot open, and also demands the use of flat glass/plastic.

I was thinking about the Lamborghini Miura, which has a side windown profile not dissimilar to the Nova. But in the case of the Miura, the side window is curved, and fits in the aperture because it is recessed into it, so that it doesn't have to follow the line of the windscreen A-pillar, which is straight, not curved. It got me wondering if a recessed side glass with some curvature would look better, even if it doesn't open. The early Countach replicas used flat side glass, which was such a giveaway (and that's before you saw how the Brightwheel side windows worked - like a 2CV!!!).

Of course, windows like that would attract wind noise and might not be so effective at "self-clearing" in wet weather.

With Alex's canopy mods, his side windows have that "recessed" look, shared with Eagles I've noticed. To my eyes they somehow say "proper car", probably because the only cars that share the Nova styling are (a) the 1979 Aston Martin Bulldog, and (b) the 1980 Citroen Karin. The latter didn't even have an engine!

Lauren

Big Birds Car
12-12-2010, 08:49 PM
Not sure what has happened as I have already replied to this after Vassco as he has a point, but it hasn't showed up.
Anyway my answer was that if you already have vents in the rear bulkhead but going to the wheel wells why not connect them to the two "air intake vents" on top of the rear wings. I'm sure that in the past someone did a bit of research and found rather than supplying air to the engine area they infact sucked air out when travelling. When the vehicle is stopped they would still help remove air from the cabin area if a fan was forcing air into it.

JemP
13-12-2010, 08:44 AM
Although air con would be nice, we sometimes forget that you didnt get air con in the confined cockpits of GT6's or TR7's or MGBGT's and we survived. I ran a TR7 for two years as a daily driver, and it had no sunroof either, it did have windows, fans and vents, and driving along it kept me reasonably cool. The problem is always sitting in traffic on hot days, when the fans just blow warm sticky air in and out of the cockpit.
Of course, the Avante has proper wind down windows, and you can also take the whole window out of the door for a full opening. I was toying with the idea of fitting a wind down rear window like the Honda CRX, but its a tad complex.

Vasco Da Gamer
13-12-2010, 05:07 PM
I looked at the November calendar shot of Alex's Nova and indeed the "drip deflector" is beautifully subtle, what a shame it is not completely effective.

Personally I think that kind of subtlety is an integral requirement - otherwise the essential "aircraft canopy" look is lost - along with part of the Nova/Reek/Sterling's unique appeal (for me anyway). Wind noise-wise I can't hear anything above the engine and carbs either.

Perhaps Jim had the right idea all along and we should be looking at these kinds of things:

http://shop1.actinicexpress.co.uk/shops ... nd_Comfort (http://shop1.actinicexpress.co.uk/shops/partsforaircraft/index.php?cat=Convenience_and_Comfort)

We still get to keep the "bonded one piece" look whilst having some sort of air local to our heads when it is raining. Of course placement would have to be carefully considered.

I had never noticed that the Miura has curved windows, or that slight recess at the top either; looks great, and definitely a "proper car" look, but who wants one of those ! :wink: ... other than for every day practicality, winter driving, reliability, visibility, safety.... um....

Mind you I also hadn't noticed the clever way the Miura door handle blends into the fins at the back of the side windows until I looked closely - very pretty. The Karin was always one of my favourite concept cars (not that I would have remembered what it was called) - because of the driving position and general wedgyness of it. The Bulldog I am less keen on, too many poor Countach references. I hadn't realised there was such a dearth of flush windowed cars around....

On your Reek Cyco, I think I follow the description - I remember seing a post with a link to a load of piccies of your car - I will take a look (at work right now). The solution sounds "simple" - which is what I always hope to aim for.

I sincerely hope BBC's possible forum post suggesting the upper rear air intakes might not work is not true - cos that's exactly where my engine gets its air from via big round ducts !

I always liked the Avante precisely because it has Miura-esque doors by the way.

Oh I don't know, roll on Star Trek style force fields for instant on/off windows.

Steve

Spacenut
13-12-2010, 09:15 PM
Snap vents, those are what I was on about. I see I can get them from Demon Tweeks too, in a choice of sizes. But I would need plastic windows to fit them into.

I hear what you say regarding the "normalness" of non-flush fitting side glass. I guess its one of those features that help to make the Nova special. But just imagine if, for example, those side glasses were recessed into the canopy by say 10mm - the whole window could be fitted into proper sealing channels and retained with beading strips from inside, even engineered to slide backwards into the B-pillar (although this would only allow a narrow slot of clear air along the A-pillar, it would still be a relatively large area). There may even be enough room for the window to retract down into the canopy sides, but the tumblehome would restrict the opening. Perhaps curved glass would help there...

My existing canopy is rather hacked-about anyway, perhaps I can use it to prototype the necessary changes... its already been the test-bed for the offset wiper (I've transferred all the dimensions to the new canopy, so the pantograph geometry can be retained).

Lots to think about, that's for sure...

Lauren

Dirk
13-12-2010, 11:20 PM
I have thought about even sliding them back into the body / rear wings and having a micro switch infrared sensor set up so you could not open the canopy until the windows were closed.

Dirk

CyCo
14-12-2010, 01:54 AM
On your Reek Cyco, I think I follow the description - I remember seing a post with a link to a load of piccies of your car - I will take a look (at work right now). The solution sounds "simple" - which is what I always hope to aim for.

The photo of my 'reek in my sig in every post is a link to my PhotoBucket account (http://s4.photobucket.com/albums/y105/cycoholic/). ;)

Peter
14-12-2010, 05:04 PM
On the SS we have reart opening side windows with the over centre catch at the rear, with good air input from the front into the cabin and the windows 'opened' there is quite a good air flow, I still fancy air con though, maybe an electric motor driven compressor unir from a small car.

Spacenut
14-12-2010, 07:24 PM
I dare say you need A/C in the summer months over there. Are there electric motor driven compressors available? I did wonder what little stuff like the Smart uses for A/C.

I've really gone off the idea of engine driven compressors - I wasn't awash with power to start with, and throwing away another 8% or whatever just doesn't appeal :nonono:

bushboy
15-12-2010, 12:20 AM
I dare say you need A/C in the summer months over there. Are there electric motor driven compressors available? I did wonder what little stuff like the Smart uses for A/C.

I've really gone off the idea of engine driven compressors - I wasn't awash with power to start with, and throwing away another 8% or whatever just doesn't appeal :nonono:


Ah yes Lauren, but is that 8% not well spent when you are stationary, in traffic, on one of the UK's finest Motor (parking) ways?

When you want the extra 8% back, for your favorite twisty bit, turn it off.

And with your access to aero-space technology, I'm sure you could rustle up a Full throttle over ride that will turn the compressor off when your are over taking?

Just some food for thought.

Bushboy

letterman7
15-12-2010, 12:58 AM
Seems we've covered A/C systems before, but to Lauren's concerns for airflow: I ducted to two vents embedded in the sides of the cockpit from each of the nostrils on my old Sterling, and left the fan driven center vent in place. With the pop/tilt windows it wasn't too bad except on really hot days (say... 85 degrees or better) when nothing helped at all. The "nostril vents" were wonderful up until about 40mph when the flow seemed to even out - that was either due to the laminar flow or the lack of air transfer/evacuation as that had never even occured to me.
One option for the embedded window NASCAR style vents would be to have a set of window glass waterjet cut then tempered, if you can find the right folks to do that. Tinting would certainly help - I had mine tinted (non-professionally by me) to 60% and it did make a difference. A white or silver dash cover for when the car is parked makes life even better when getting in after a long day.
As for electric driven A/C... search some previous posts about my testing RV and marine refrigerator/freezer self-contained systems. Definately worth a look-see if you know someone in the HVAC business that can help set up the tubing and charging of the systems.

Spacenut
16-12-2010, 06:31 PM
Thanks Rick, that is very useful advice. Hopefully my local glazing people will have forgotten I messed them about 3 years ago! Perhaps this time I will finally get as far as placing an order for a set of side glass. Whatever I use, it will be tinted to at least the same degree as the windscreen.

Martin, I know you are right about A/C compressors and they cause minimal load on the engine when disengaged. The other aspect is just the weight of the system; Green Machine is overweight as it is, adding the compressor, evaporator/drier, heat exchanger, plumbing and refridgerant will only make things worse...

Still pondering...

Lauren

islandman
17-12-2010, 12:38 AM
Green Machine is overweight as it is, adding the compressor, evaporator/drier, heat exchanger, plumbing and refridgerant will only make things worse.

Lauren, Simple fix! Fit the compressor, evaporator/drier, heat exchanger, plumbing and refridgerant then go on a diet to compensate for the weight added, problem solved! :tongue:

essexdave
17-12-2010, 02:46 PM
:crylol: ...... islandman i hope your life insurance is up to date.

bushboy
17-12-2010, 11:01 PM
HELL has no fury like a woman scorned :@ :@ :@

Island man your a braver man than I

:twisted: bushboy :twisted:

Dirk
17-12-2010, 11:45 PM
Island man I take some of your heat. :whip:

Lauren you could always put in a better engine perhaps a Subaru and not worry about the 8% :munky:

Dirk

islandman
18-12-2010, 01:13 AM
Luckily I'm hoping the fact I have known lauren for what must be more than 15 years may save me :crossfinger: :oops2: and the fact she isn't overweight so will know its a joke! :sorry:

Spacenut
18-12-2010, 05:27 PM
Today I'm in a good mood, so I think you'll survive :D

I still think I would have to shed quite a few pounds to counter the weight of the A/C. Engine power will be increasing to around 140-160 bhp (eventually), but I'd like to increase the power-to-weight ratio, not keep it the same!!!

Lauren

islandman
19-12-2010, 02:24 AM
Engine power will be increasing to around 140-160 bhp (eventually),
Lauren

So are we talking a new engine or turbo charging? :whistling:

Spacenut
20-12-2010, 07:24 AM
Hi Dave - I'm not a big fan of forced induction (more from the inevitable complexity point of view than anything else), the engine will be normally aspirated and running on carbs. I have had a kit of parts to make a 1.6 litre stroker engine for some years now, I just need to get the gearbox angle and exhaust system sorted before putting it in. Its a 1.5 litre Alfa block with the 1.7 litre crank in it. With special Cosworth pistons it displaces 1600cc, but keeps the strength of the block because the bore size stays the same. Its got special gas-flowed heads, stainless steel valves and inlet manifolds designed for 44mm IDFs or 45 DRLA Dellortos. I've got an old 1.5QV engine which I have stripped for the remaining parts needed to complete the build, but I would have to source the cams and carbs.

Alternatively, I have been offered a similar specification engine already built (by Alfatune), with 45 DRLAs and 2D mapped electronic ignition, which might save me a bit of work!

Either engine is good for between 140 and 160 bhp, depending on cams mainly. The Alfa boxer is a torquey engine and I wouldn't want to lose too much tractibility on the street just so I can boast about my bhp :D

Lauren

jim73vw
24-12-2010, 01:27 PM
Hi Lauren,

Just read this thread and reminds me of the debates I had re Nena's side windows.

Harry's Gizmo also had reprofiled sides to the canopy to allow for glass windows and he did try to persuade me to go this route when building Nena, but I was close to paint and couldn't face more bodywork!

In the end I used http://www.plastics4performance.com/, and sent them templates of my windows and headlight covers.

They cut to template, and leave a really nice edge, and then put a black factory finish looking band around the edges to the thickness you specify, which is designed to take adhesive for bonding, and helps finish the look and hide the glue and bodywork behind. I had a local windscreen fitter bond them in form me for 30 cash! He made it look easy, and had previously done losts of TVR bonded screens so had the knack !

Plastics for performance also cut the holes for the pop it vents I had, and supplied them. You can spin them around when fitted to either blow air onto you or even back to the screen a little, and when snapped shut they are water tight. I found them to really help air flow through the canopy, and would often run with the sunroof open a crack even when wet to keep air moving.

You can see the banding and pop it vents here:

http://farm4.static.flickr.com/3268/2574510363_5372da40bd.jpg

I cannot recall exactly as some time ago but the windows and two headlamp covers were in the 200 region delivered with vents etc which I thought was good, as the risk of cutting yourself can be expensive ! They also do various forms of perspex and films etc

Hope this helps

Spacenut
24-12-2010, 06:46 PM
Thanks Jim, that's just the kind of feedback I was after. I didn't realise P4P did the banding for you as well, that will certainly be something worth considering, even if I stick with glass windows and just get headlamp covers done.

Nice picture as well - I've not seen that one before :D

Lauren

jim73vw
25-12-2010, 08:31 AM
Nice picture as well - I've not seen that one before


An arty one by Ian Stent for CKC, we were doing 5mph!