924Board.org

[dreamgts]

Well noted RC. I will look into that alt. If it fits like I described I guess its ok then. Did you say I need the 931 AC bracket or a fabricated one? What about the remote sensing/ stop charging , does this involve an exterior switch off of some kind being fitted or does the regulator have some kind of setting to cut off charging? I know nothing zip zero about electrics and how alternators work The idea of switching off when not needed to gain a bit of HP makes it a good alternative I guess. Iv tried a lot of searching on the alternator mod but till now nothing came up regarding fitting an alternative alternator.

thanks
dreamgts
_________________
2 PORSCHE 924 (CURRENT PROJECTS)
2 CLASSIC CORTINAS (FINISHED)
1 CLASSIC FIAT(FINISHED)
1 CLASSIC FIAT 132 2000CC(JUST PURCHASED)
4 SUV'S
2 SEDANS
1 OPEL PANEL VAN
WIFES SUZUKI ALTO

[dreamgts]

This morning I managed to talk to my exhaust guy regarding the exhaust fabrication. After showing him some pics of some exhausts sent on this thread and telling him that other mods will have to be done to make it fit, he wanted to see the space available on the car itself.

During his visit he told me that the header can be done, but he told me that he might have another solution and avoid other alterations and stick with the standard exhaust header. He added that with the mods I have in mind he understands the need for a race exhaust but he also added that the standard exhaust might be modified in a way that it will have minimum affect on loss of BHP and back pressure which seems to be the main concern here.

After inspecting the standard header he told me that it could be partly polished and smoothened from the inside thus in his words making the flow of exhaust better. He also told me that since the distance from the exhaust ports to the first down pipe is short he suggested what he called a 4 to 2 setupusing appropriate sized piping. the downpipe from header to end which will be right up to the right hand side of the car just before the rear wheel( or somewhere close to that) will be totally made of stainless steel. He explained to me that since not much bends are needed to make a short type racing exhaust , this would be possible with stainless steel piping. He told me that I cannot have anything smoother than this material for and exhaust system. He informed me that by using the standard header I might loose some BHP but not that much. He also offered that he might like to experiment on this system for the 924 and was willing to charge me only for the stainless steel piping needed. What do you guys think of this? It kind of made sense to me since it would eliminate much concern although I would still go for the remote oil filter set up and change of alternator to a lighter unit, yet this would be left in its original position in order not to spoil the look of the 45 DCOE as seen on Franks car. This way a sure fit of all units is kind of gauranteed

thanks

dreamgts
dreamgts
_________________
2 PORSCHE 924 (CURRENT PROJECTS)
2 CLASSIC CORTINAS (FINISHED)
1 CLASSIC FIAT(FINISHED)
1 CLASSIC FIAT 132 2000CC(JUST PURCHASED)
4 SUV'S
2 SEDANS
1 OPEL PANEL VAN
WIFES SUZUKI ALTO

[ideola]

Sounds like a reasonable compromise to me.

If you really want to do what Frank did, you could always move the alt to the rear axle...

...here's my solution:
http://www.924board.org/viewtopic.php?t=29518
_________________
erstwhile owner of just about every 924 variant ever made

[dreamgts]

[RC]

[dreamgts]

Thanks RC for this info. I have decided to go for the modified standard header and stainless steel exhaust system, We can always try obtaining any minor loss in BHP by going this way with other mods to the engine.

As for the alternator, I have seen a pic posted by Cedric on my thread regarding 70's style wheels which shows an alternator on a 924 which is fitted very low beneath the throttle bodies, actually it hardly shows,so if I want to change position i am sure that it can be done also.

I like the idea of fitting the CS130D since as you say it can be modified to cut charging. We will have to investigate how we can connect this to a 'cut off' switch , I havnt decided on ignition system yet maybe I could find a system to which the alternator pin can be connected to and as you say cuts off power at a certain rpm. I think that the local GM agent can source this locally.

Basically I am looking for power for tight tracks and hill climb events so whatever is done has to produce power in a short distance. i have had no trouble with other makes of car achieving this since we used low geared gearboxs, and diffs with Limited slip as well as being low geared, smaller diamter tyres also helped to achiev speed in short ditances , but as I said these were other makes and not 924, I am still to experience a modified 924, Im sure I wont be disapointed. I also read on some threads that we 924 people tend to go for cheap stuff or are some sort of bargain hunters, I totally do not agree with this since sourcing parts cheaply if possible in my view means that a person is capable of doing so. For example I cannot source a donor car for lets say $ 1000 here In Malta But if I could I would, I dont think that would make me cheap. I have seen some nice set ups on the forum and all seem to have cost $$$$$. And in any case whats wrong with doing a bargain in these days where cash flow is tight.

Thanks
dreamgts
_________________
2 PORSCHE 924 (CURRENT PROJECTS)
2 CLASSIC CORTINAS (FINISHED)
1 CLASSIC FIAT(FINISHED)
1 CLASSIC FIAT 132 2000CC(JUST PURCHASED)
4 SUV'S
2 SEDANS
1 OPEL PANEL VAN
WIFES SUZUKI ALTO

[Min]

My buddy found this little goodie while looking around on summit. http://www.summitracing.com/parts/CTR-22-595/ can rotate it to any angle and then tighten it back up. A bit more expensive than the transdapt item though.

Min
_________________
Custom means it didn't come from a box.
1980 n/a with EDIS and Megasquirt II Injection. 7 different colors and counting.

[dreamgts]

Min, that adaptor seems to be a good item since it rotates, does it fit the threading of the 924NA? I think I think that the threads mentioned are the same but im not sure. OOOps gave a closer look yes they do 3/4 X 16. nice interesting item.

Thanks
dreamgts
_________________
2 PORSCHE 924 (CURRENT PROJECTS)
2 CLASSIC CORTINAS (FINISHED)
1 CLASSIC FIAT(FINISHED)
1 CLASSIC FIAT 132 2000CC(JUST PURCHASED)
4 SUV'S
2 SEDANS
1 OPEL PANEL VAN
WIFES SUZUKI ALTO

[Min]

The item posted should be the correct item for a 924, the sealing surface is also in the right place. If not they do have a variety of other threads available.

Min
_________________
Custom means it didn't come from a box.
1980 n/a with EDIS and Megasquirt II Injection. 7 different colors and counting.

[924OZY]

If you do go a twin system, the theory is there are two paths and that should halve the restriction.
Its correct if the pipe diameter is the same as the single was.
But there is also a thing called a crossover pipe that balances the pressure of both pipes. These can gain up to 10%+ power at the wheels over a twin system without one.

Going over twin 2and a quarter inch pipes would lose a lot down low.
Its about the same CFM as a single 2.5inch.

With regards to the crossover pipe,
A good length is about 10 inches long.
Basically a the two pipes must be next to eachother and a larger pipe that has been squashed in a vice, to fit over both pipes is welded to the end, a good length for this would be about 10 inches,
longer should work better down low and shorter up top,
like most things to do with pipe length in an exhaust.(they even sell them off the shelf now).

Our Touring cars use them and your Nascars probably do too.
_________________
924 N/A snailshell, superpro linkage bushes, 2.5"exhaust

4.0L ef Fairmont, 3000rpm stall, shift-kit, J3 chip, 3" exhaust, self tuned using tunerpro, soon to be boosted,
expecting 350Kw at wheels at 10psi.