ALFAGTV6.COM

[Jarle]

Hi folks.

I have been watching the discussion about headers for the 3l V6 12 v engines. As the products available are few I decided to build my own manifoil. I considered to buy the CSCs but I can not get any software or calculations to make up for the lenght of the CSCs. They produse good power in low/mid but I can not get the big horsepower with them(simulations).
Any comments/experince?

Thanks
Jarle

[Mats]

Looks very good! Primary length?

[Greg Gordon]

Wow Jarle, those look fantastic.

[Zamani]

WOW! Primary size and length?

And those intake ports look huge!

[tImBoWe]

Very cool! Where would you expect the power/torque peak to be with that length of primary? Any other mods?

[Jarle]

Thanks. Primarys are 28", OD 1 5/8. Have eksperimented with larger OD but it has a bad effect over hte whole powerband exept above 6500rpm.

tImBoWe: other mods are custom intake with larger intake ports and ITBs from Suzuki GSXR, much lift and duration, high compression pistons, pulleys flywheels and camsprockets in very light alloy, and lots of other changes.
Expect peak torque at 5200-5400prm, and peak power at 6400-6600rpm. The power curve should pass the std V6 curve at about 3800-4000rpms.


Jarle

[Zamani]

Jarle,

Didn't you make a set which looked very similar to the CSC except with bigger primaries?


BTW, do you have a jig? How about making a few sets for us here . No real welding needed, I mean just a few tack welds. That's all we need.

[sira]

It look very cool, now you can put two turbo's on that headers

[Zamani]

Is collector shape important?

[TS_turbo]

merge type collector with ventury is best you can have
http://www.burnsstainless.com/MergeColl ... ctors.html

[Zamani]

Yes, I have burnstainless collector where the 2 secondary pipes merge. But I was hoping to avoid it with 2 X 3-into-1 collectors. They'll cost about $500!!!

I found cheaper formed 3-into-1 collectors, but I don't know if it is a smart compromise... the formed collectors are only $8 each

[Jarle]

Zamani: yes i built a copy of the CSCs for another engine setup.
I get the bends from www.stahlheaders.com Got a large package from them weighing just above 30 kilograms, and that is expensive to ship to Norway. Then adding the cost of the bends with the time it takes to build the headers and shipment back to the US it wont be cheap
With these nice bends you can make your own system with just a simple "metall saw" and a welder, no big challenge.

Use the stahlheaders 3-1 collectors. I am not an expert at this, but my oppinion is that it has minor importance weather you use a reasonable designed merge/baffle collector.To put it another way, you will never make big horsepower with badly tuned primarys and a good collector. But there is a good chance of making good power with tuned primarys and a "bad" collector.

[Zamani]

Thanks for the info Jarle. BTW what do you recommend, 18 gauge thick pipes or 16 gauge? I think 16 would be better for heat retention and strength.

[Jarle]

Zamani: Agree, for a daily driven street car 16 guage should be just fine. I use 18 guage only to save weight.
Right now I am designing new ultra light mufflers, with 20 guage inner cores and very thinn alu body. These can be taken apart and overhaul in 2 minutes.

[MD]

Jarle

A big pat on the back for having a go !

One tiny bit of advice to help you along. Using aluminium for exhaust components could be a problem of short life. The reason is that all fuels have some amount of sulphur in them and when the gases reach their "DEW POINT", they will form sulphuric acid. This will strongly react with the aluminium to munch holes in your fabrications.

Try a little experiment. Get some sulphuric acid and introduce some aluminium into it (taking all necessary personal protection first of course). Observe what happens to it. The same will happen to your components but at a slower rate.

Your call..