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Schrick cams with a charger


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  • 1 month later...

well 248s are known as the charged cam.. I dont know why. I just remember that they are what people tend to use.

I think it had something to do with the ignition ppoint and retard levels giving torque...

Read in to that what you will. It was a long time ago.....

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well 248s are known as the charged cam.. I dont know why. I just remember that they are what people tend to use.

I think it had something to do with the ignition ppoint and retard levels giving torque...

Read in to that what you will. It was a long time ago.....

cheers mate will do some more reading then about 248's as well :) cheers

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Nope' date=' Schimmel 263'S would be better, 268's are abit lairy for F/I

[/quote']

how about 260's or are they not lairy enough !! :)

I bought my DR268's with the intension of fitting a schrick, but the decided to charge it instead so sold the cams, I seem to remember the problem was somethig to do with the cam overlap, dont know what it means but took their advise as they know alot more than me about that sort of thing, I think its basically a leak in the boost pressure as both the inlet and exhaust cams are open slightly at the same time?? If anyone know for definate what it is post up as in quite interested

Ive since seen a few time that schimmel 263 will see fairly impressive gain with a charger, IIRC it was something like 30ftlb and have an impressive track record from what ive seen, considering their price, id have them over schricks any day

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I bought my DR268's with the intension of fitting a schrick' date=' but the decided to charge it instead so sold the cams, I seem to remember the problem was somethig to do with the cam overlap, dont know what it means but took their advise as they know alot more than me about that sort of thing, I think its basically a leak in the boost pressure as both the inlet and exhaust cams are open slightly at the same time?? If anyone know for definate what it is post up as in quite interested

Ive since seen a few time that schimmel 263 will see fairly impressive gain with a charger, IIRC it was something like 30ftlb and have an impressive track record from what ive seen, considering their price, id have them over schricks any day

[/quote']

cheers mate was hoping you would turn up and post :) right then will go searching for some schimmel 263's - cheers mate :)

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Nope' date=' Schimmel 263'S would be better, 268's are abit lairy for F/I

[/quote']

how about 260's or are they not lairy enough !! :)

I seem to remember the problem was somethig to do with the cam overlap, dont know what it means but took their advise as they know alot more than me about that sort of thing, I think its basically a leak in the boost pressure as both the inlet and exhaust cams are open slightly at the same time?? If anyone know for definate what it is post up as in quite interested

This i do know about - In a few words rather than a book full of words.... you're not far off the mark at all!

As you can appreciate the extra heat in the chamber from the charger means the chamber stays hotter for longer. Therefore as the point over TDC passes and valves etc open and close in simplistic terms. The hot gas escapes and the cylinder doesn't cool down enough to draw the air/fuel mix in and sufficiently mix thus making less efficient. (yes it still draws in and also hot gas is not as dense as cold gas -less bang)

In addition you can preignite a lesser mix due to latent heat in the cylinder or even valve heads.. So an amount of time is needed for this "crossover". You shouldn't/wont have them both open at the same time but is almost like that effect..

As you can then appreciate you retard the timing and you pass the point of benfit and end up with an 8 stroke engine misfiring LOL I

There is a lot more to it but you get the gist... ( I hope)

If you want to read may I suggest this bible http://www.amazon.co.uk/Forced-Induction-Performance-Tuning-H691/dp/1859606911/ref=sr_1_1?ie=UTF8&s=books&qid=1236108297&sr=8-1

Cheers

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