K24 Headers & exhaust - Dyno tested k24 pt3 

The extremely telling part of it is road speed vs output. Also 100hp/L /at the wheels/. In a car. Without going 100% motorbike on revs.

Super like bro👍👍👍💯

Would like to know what software you use or how you're calculating runner lengths and diameters for the headers you make. You seem to be spot on straight away...unless there's lots of behind the scenes trial and error we don't see!

@@danielmalone3463 These ones where just based on what works on my 4age stuff. the diameter is bigger for extra capacity/power. probably more in it with a bunch of testing. big exhaust and primary diameter not being to big is key to the bottom end gains

Just done larger throttle and ported intake on a friends car, would be cool to see the difference.

Nice. are you building the setup from scratch or adapting something?

Try virtual Dyno if you can get or convert to megasquirt logs

@@ReubenHorner I did something similar in excel. I calculated the torque and power required to accelerate at that rate, assuming the weight of rider+bike, using gearing/tire diameter from manufacturer specs. Disregards rolling resistance, aero drag etc, just the remaining force available to accelerate. Gives a graph similar to dyno, good enough for comparison of runs. It's the differences that interest me, not the absolute numbers.

Yeah big difference.

Also interested in whether the 'megaphone' conical expanding collector thing you've used before would have any benefit here?

I'll write that down. Any lengths?

unsure of brand. but the ones on there weren't stock. assuming you're talking about the headers

@@Garage4age that was PLM the DTR replica header.

Bit of everything. assume your have watched the 2 previous videos? I did try the old header dropped off after the de-cat pipe, which was bigger than rest of exhaust. it picked up some bottom end. so they would have worked better with the bigger exhaust yes. but maybe not as well as the new headers. the 4 section on the old headers step up to a bigger diameter. which usually hurts the bottom end.

​@@Garage4age Exactly. Big tube headers will lose mid all of the time. It just sounds cool and builders can sell them at high price to uneducated.

@@Garage4age yepp, I watch every video you upload despite being a Honda B series NA guy only making 250hp from ~2liter. With your dyno trial approach it would be 300 I bet. Unless being a high end engineer with good simulation SW your way is the one to follow.

The change from a 60mm rear exhaust section (Mugen) to what looks like 76mm would have made a huge difference too! It's a little hard to separate the performance of the (exceptionally designed and made) header from the general improvement from increasing the rear exhaust diameter. Edit -- Actually, it's really frustrating that nobody ever seems to test 70mm v 76mm rear exhausts on these cars. I'm so curious if 70mm already gets most (or all) of the benefit.

I've got some factory injectors from a bike that has them mounted both down by the port, and waaaayyy up above end of the trumpets in the airbox (BMW S1000RR) The upper injectors have a wide foggy spray pattern, not a narrow cone like I would have expected. Seems almost like they aim to fog up the entire airbox. Interestingly, trying injectors in different locations on a car engine. Resulted in zero power difference but considerably worse wall wetting issues on transients when the injectors were mounted further out. My theory is that outer injectors are only needed on super short stroke motors where the piston draw does not mix air/fuel well in the cylinder. In combination with rpm that car motors dont reach (10k+)

Haha, it sure does.

Rpm is on the top

@@CL9k24a3 I don’t see it Unfortunately I can’t attach screen shot form 3:46 How about the lengths and tube diameter

@@steveyoutube1709 RPM is in the big graphs. Dyno wont show it in the small raw/real time graph. the new headers are 44.5 od. the old ones start same size then step up bigger half way before the 4-2 merge.

Hey. They are a one off sorry. material cost is almost as much as the mass produced items. and they are labor intensive, as make my own collectors and everything.

😂 too easy

pretty sure they are just stuffed. maybe the owner will buy some more..

Just looked them up, and yeah seems they are those headers. yep good part of its the exhaust. I didn't back to back test them as was over crawling under car and the old ones dont compute with new exhaust. I did try the old ones dropped off at the decat/test pipe at one stage and it gained down low, but didn't seem as much as new setup. wasn't apples to apples test, so no point showing it. Makes sense as the old ones step up to a bigger primary size and the new ones have a better cone section after them, which will both gain off the bottom. could argue cone section is part of the exhaust though.

Maybe doing some intake stuff next. It already has an aftermarket 70mm throttle. assuming " s90 70 " is a 70mm throttle.

The Gruppe M / Tegiwa intake has the filter in the same spot, but enclosed and actually ducts in cold air from the windscreen scuttle panel high pressure zone!

rpm is at the top on big graphs. i cant change the other one

big exhaust after the headers and collector will help off the bottom/mid on an engine with decent sized cams. hence why i was able to switch to the big cam profile earlier. if ran the big profile down there on the old setup would make even less power. less pressure in the exhaust helps with reversion at low air speeds. but doesn't work if header primary's are too big. The old headers had bigger stepped primarys. they possibly would have gained a touch of top end combined with the bigger exhaust. but wouldn't have gained anywhere near as much in the middle

@@Garage4age dude, thanks for your comprehensive reply, you are a true source of knowledge. I was suprised in a first moment that a K24 comes with a standard 2 Inches pipe, such pipe diameter in a 2.4 liter definitely sounds weird not to say ridiculous, but when I saw the big pipe one thinks 'definitely this will make the scavenging worse and only will gain in the top end, losing lots of midrange/low end' How deluded I was lol. Thanks for these videos!!!

The exhaust has a weird tingle noise to it, unsure why haha. no knock, I always check with headphones

unsure, engine was already in car when i got it. known spec's in description

headers 44.5mm od. from memory the choke point was 2.25" or 2.5" , double cone to 3.5" then back to 3" inside first muffler

Yeah was stock engine with bc stage 2 cams. test engine specs are in description of all my videos

good part of it, but it also doesn't work if the primary's are too big.

@@Garage4age would be nice if you can test direct comparison header vs header with same exhaust. Maybe just sick megaphone on it and test them that way?

aem , known specs are in description of my videos