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I'd imagine it probably feels pretty good without all of that weight and the extra power you gained (pretty cool engine you built BTW).
Out of curiosity, did you ever drive the car with the stock suspension after you took out all weight?
Hi,
I drove it daily for 6 months all in standard form, then took off approx. 140kg from the 1260kg stock weight and drove it for a few months before it was off the road for 2.5 years! where another 110kg was shed.
I had fitted gas rear Spax dampers but stock fronts and it drove ok, felt lighter and more nimble but the ride height had risen by 30mm! so it was sitting well high and had lots of "Rock and roll".
The Engine, Box, Rear axle and fuel tank all came out and the lump was replaced with the 2.7 Lindsey Racing Engine and the box rebuilt, LSD installed and all the rear axle and fuel tank restored and painted etc....
They when it was all Re installed the Race team Set the Ride heights and corner weights just over (250kg each corner) and it's good but a tad too stiff and lacks movement on rough roads and lumps and bumps....
I've got some Bilstein B6 dampers and Hyperco 160Lbs springs to try on the front, but before this R&D I'm gonna try it on track as it is just to see
if I feel it has potential to take it off road (Again!!) and Race it properly...
Go on Ecomodder.com and bone up on undertrays, especially Coroplast.
The Porsche 944 is an ideal candidate for a Coroplast undertray, a very inexpensive, durable, light, and efficient means of improving higher speed fuel economy while substantially reducing road noise. It would also lend itself admirably to making a diffuser at the rear, which would further reduce drag while increasing downforce. The rough and irregular bottom of a car is typicaly about ~1/3 of total aero drag, so this is a target-rich environment with much potential to inexpensively reduce drag, while protecting the car bottom from salt spray and crud in Rust Belt areas. Smoother airflow makes the car a lot quieter, as the Coroplast reflects tire noise away, while giving a bit of sound proofing.
Mirrors may be ~6% of total aero drag, and the stock flag mirrors are not good, as their frontal area is not nearly as small as the actual glass mirrors, and the flag shape is poor, the strut shape is terrible. Porsche aero teardrop mirrors would be better, but are unduly expensive. A better aero choice would be modified motorcycle mirrors of better (teardrop) shape and significantly smaller size, for reduced frontal area), as well as an airfoil-shaped mount.
Wheels are another big deal, aerodynamically. Sewer lid or Design 90 wheels are about the best Porsche OEM types, because their outer face is smooth and not cupped. Cookie cutter wheels or other irregular-shaped spokes with deep dish are about the worst...
The lower front fairing shown on the 928 picture above deflects air out and around the very draggy leading edge of the front tires, which themselves are a major drag source.
The entire nose of a 944 could be redesigned for major drag reduction, made to look more like a typical NASCAR nose, with smooth radiused curves fairing the front wheels, plus a chin splitter to keep air from building up under the nose.
Merely speculation, but I suspect a hood vent is probably in the top list of improvements to do on our cars, though made inherently difficult because of the backbone of the hood. Air comes in and out of the rad and over the car adding to down force. Absolutely BRILLIANT. Another problem for the central hood vent design is the distributor is in the way on our 8 valve engine. What is involved in order to "flip" the cam shaft around? Or is the best answer wasted spark?
Mirrors may be ~6% of total aero drag, and the stock flag mirrors are not good, as their frontal area is not nearly as small as the actual glass mirrors, and the flag shape is poor, the strut shape is terrible.
Wheels are another big deal, aerodynamically. Sewer lid or Design 90 wheels are about the best Porsche OEM types, because their outer face is smooth and not cupped. Cookie cutter wheels or other irregular-shaped spokes with deep dish are about the worst...
Wow 6% !
I binned the draggy heavy Flags, and the 500gram Saloon Racecar Replacements must be better then, even though I've had negative comments of a cosmetic nature they function well! and are much smaller and don't have the a slabby flat back.
My wheels have got a flat centre (after machining) but the 5 spoke design probably cuts up the air and causes drag right?
My wheels have got a flat centre (after machining) but the 5 spoke design probably cuts up the air and causes drag right?
R
But you probably get a good amount of brake cooling from them anyways and they probably don't weight very much. I'm no expert but I'd be willing to bet the brake cooling alone makes a larger difference in performance than the turbulence they create. You'd obviously have to test that out but that's just my 2 cents. Even then, brake cooling ducts are pretty cheap. Other things like a front splitter or a larger rear wing like yours or venting of the wheel wells probably make a bigger difference. If you are worried about that though, pick up a set of BBS Turbo Fans
Merely speculation, but I suspect a hood vent is probably in the top list of improvements to do on our cars, though made inherently difficult because of the backbone of the hood. Air comes in and out of the rad and over the car adding to down force. Absolutely BRILLIANT. Another problem for the central hood vent design is the distributor is in the way on our 8 valve engine. What is involved in order to "flip" the cam shaft around? Or is the best answer wasted spark?
See above post with the 924 in Hugo Boss livery. Venting off of the stock one is still possible. Not sure if he's moved anything underneath but doesn't seem like it.
But you probably get a good amount of brake cooling from them anyways and they probably don't weight very much. I'm no expert but I'd be willing to bet the brake cooling alone makes a larger difference in performance than the turbulence they create.
Brake Cooling is not something I've done anything with (or considered) as the build was for a road car and the 20 Piston Wilwood Servoed (Non ABS) Brake System is immensely powerful with a car 500Lbs less than stock.
In reality after 2000 Miles I can safely say my choice to fit the Softest Pad compound was correct, as the amount of extra power and less pedal effort required compared to the stock iron calipers is so much less they do not get into any State of getting Too Hot and requiring any Cooling requirements.
However next Friday's track day may be different? but I don't think they will be an issue. The Knife Edged Crank slows the car when the throttle is lifted quite dramatically, the loss of Inertia is so great the brakes are not required as much as a standard car which of course also requires more effort to stop it due to the extra 500 Lbs+ and the original Iron stoppers are "Pants" in Comparison to 6 & 4 Pots as you'd expect!
change out your 944 stock upper rad hose for the 944T setup (hard pipe and short hose out of the way...
there will be a fair amount of space between the engine and radiator/fans now visible...build a duct/channel up to the hood, cut your hood-hole there...
Originally Posted by Noahs944
Merely speculation, but I suspect a hood vent is probably in the top list of improvements to do on our cars, though made inherently difficult because of the backbone of the hood. Air comes in and out of the rad and over the car adding to down force. Absolutely BRILLIANT. Another problem for the central hood vent design is the distributor is in the way on our 8 valve engine. What is involved in order to "flip" the cam shaft around? Or is the best answer wasted spark?
A hood vent is probably in the top list of improvements to do on our cars,
Air comes in and out of the rad and over the car adding to down force.
You forgot to mention why or how it adds downforce, because less air is travelling underneath the car after the vent.
Without a vent for the air to exit the radiator air once through the rad has nowhere to go and dissipates through the engine Bay and underneath adding to what's gone under the airdam already and increasing rear lift (Drag)
Just like the Wheel Arch vents where air that goes under the front airdam is released up through these vents, and not underneath.
Unyet I see a trend now in (F1 & Le Mans WEC) where air is encouraged to go underneath.
we've reported, discussed, and talked it over dozens of times on these forums over the years....... the oem 924/944 aero is very suspect at high speeds. the 944 suffers from significant front end float after 115mph. the front end of the 944 'get's very light' past 130mph. it is what it is. ....drastic measures, including complete aftermarket noses and splitters are required, and regularly done to add downforce up front.
the 968 was designed in a wind tunnel, and is more stable. at top speed, the cars are a bit 'light.' front downforce can be improved with splitters. ....it can be improved even further with other nose designs. there was a Hungarian aftermarket company some time ago that came up with a few new, interesting front end designs for the 968 inspired from the 996 era that will add more downforce. ...and there have been others. the 968 can be made to produce downforce by somewhat less drastic means than the 944.
the rear ends of both of the cars are very similar. the 968 Turbo S/RS wings are the best solution for the street.
the necessary aero upgrades result in slower cars (requiring big power upgrades).
10-26-2016, 06:16 AM
