Thanks for the good information Guy, this is the first time i have ever tuned a turbo engine so all correct information is valuable, i will get the book

regards Mick.

Happy bidding. (note to Guy you will get more hits if you put your name in the listing title)

http://cgi.ebay.co.uk/MODIFYING-AND-TUNI...b#ht_500wt_1156

Guy true or false, a five cylinder engine is more troublesome than a 4 pot or even a 6 cylinder where you can use a twin turbo setup. Because of the closer proximity from seperation of the exhaust valve events ? Even longer primarys than usual needed here ?

Aha, many thanks sir.

I just have to add as an off topic note that I have a sizeable amount of knowledge about engines and tuning, more then many - or so I thought until I got the new GC book. It covers subjects in an approach deviod in the numerous books I already own (streets ahead of the already good Forced induction Tuning by AG Bell).

Just for info Nigel I would say save yourself some fuel use in week and put that money on the book, its a real eye opener, I bet if you pick it up you wont put it down (its not good for marriages).

rich

The five cylinder engine must be a can of worms for exhaust header design engineers. I can only imagine that dealing with the three phenomenas that occur when the primary wave ‘hits’ the collector must be a nightmare due to the extra (odd) cylinder compared to ANY other engine configuration known. Even cylinders can be paired off and the use of twin entry turbos can aid wave attenuation. But a five pot?!?. I have always said that getting the exhaust manifold design correct is key to unlocking this engine. I am yet to see proof of this. (Maybe we should ask Audi Motorsport )

I have read many books including A G Bell but GC's new book is a serious read. It solves my insomnia problem quite well.

But the fifth cylinder isn't an "extra" as such - it doesn't just shove a pulse in at some random time

All that happens is that the normal 90 degrees pulse separation of a four pot is reduced to 72 degrees for the five

Admittedly, it would prove problematic for the implementation of parallel twin turbos, but that's pretty unlikely to be developed for the Coupe. Twin sequential would be interesting, but probably wouldn't provide enough gains for the investment

I'm sure that Audi Motorsport will have some good experience, but IIRC, even the hottest Quattro WRCs were 'only' putting out 500 - 600 bhp - we've already seen the lower end of this range from a 2L Coupe and our budget is rather less that Audi's was at the time, PLUS our engines aren't stripped and rebuilt every weekend

"All that happens is that the normal 90 degrees pulse separation of a four pot is reduced to 72 degrees for the five"

Ooops. On a four stroke unit it takes 720 deg of crank rotation to complete the full cycle on all cylinders; the separation is 180deg and 144 deg resp.

G

Nigel, there are two full revolutions to the 4 stroke cycle hence, a 4 cylinder will fire once every 180 deg.

I knew that.....

TBH, I was trying to remember the info about primary and secondary vibrations - I just didn't bother to think that there's only one firing stroke per two revolutions

Thats what I was saying !

OOPs. I think our posts overlapped!


G

I personally wouldn't spend my money on that, based on the advertisement.

The curves in that manifold are way too sharp and close to the exhaust port. Look at the #5 cylinder. How on earth is any super-hot exhaust gas going to get out of the cylinder there? Sod equal length here, you want equal (and high) flow and these ridiculous bends are not going to help at all. It sure look pretty, but the design has some obvious bottlenecks in it.

They stated that they used CFD design on this manifold, but I think that they merely went for the best possible flow with 36mm pipes and stock dimensions/locations of the flanges, plus equal length. If they would have dropped the equal length from the requirements and replaced it with equal flow, they would probably come up with something entirely different.

I know it's guessing based on just one advertisement, but this is exactly what they want you to do, decide to buy their product based on the ad.

If I'm wrong about this manifold, someone please educate me. I'd love to learn how this setup can work.

Hi, i know something also, but know for sure its not enough, so hope my 100 bid will be enough. And i only have experience with turbocharged engines. But eager to learn ofcourse.

Regarding the orientation of primaries on a 5 cyl the only sane way to to do it is 5-1. Attempts to 'pair' the pipes would only lead to rather bizarre variations in vol effy & firing pressure.


GC

Surely they also work with the room there is, and not like guy likes it to be, or even better how it should be. One way might be an different castversion but this will still be an compromise and nothing more. Who has an spare head

Hi remco, this is what I was saying on delphi the other week if you remember about re-locating closer to, or over the gearbox.

Hi,

Indeed i remember ofcourse .

Did you worked something out already, sizewise or something?

You can always contact me if you want to give it a go.

Regards remco

Not yet, It's a while off (still no engine in the car). I need to think about a lot of other factors first.

Maybe we can come up with something very nice in the future, well for a 16v anyway.

Most likely for your car only then;)

Not especially just for me, the 5 cylinder unit does'nt interest me for starters, I would be more concentrated on a nice manifold for the delta specificaly. Once 1 is made and TESTED who knows what might happen, if there is a demand.

Integrale specific, are you allowed to say that over here;). But no problem, just let me know when you are ready, dont think there will be much interest from others though.

All the luck with your build sir.

regards remco

surely i was not even going to try to pair cilinders with the 5 cil.manifold , but maybe the reply was not ment for me

yes, 5 cyl header - it's my lack of familiarity with the reply procedure, sorry. Some folk no doubt wondering why I appear to be replying to them on er,'unrelated issues'..

G

For sure no need to say sorry, i dont mind at all ofcourse. And i think in the end everybody is more then happy with any reply you will or can make on any forum.

Regards remco

Thanks very much for buying my book Remco, I've emailed you for your address..

GC

Just to add Nigels advice,the only thing i changed from getting near 500bhp was the manifold and now its running just over 400.
So i too will be reverting to the stock manifold with a few machining extras.

Would love to see a tried and tested solution though.

Welcome sir, it will be an interesting read for sure .

Regards remco