Exhaust design thread...

[wagoon 2,429]

Is it possible to get another cheap set of extractors cut the mounting plate off then make two different sets with a flange at the collector so the can be changed easy?

[matt_lamb_160 252]

PRO, in my opinion Pacemaker know very little about pipe sizing. The 1 5/8" primaries yet small exhaust outlet on their crossy extractors are a perfect example of what they know. Also for most road cars/cars revving less than 5,000 short primaries long secondaries are the go, but Sly's beast is a different animal.

 

Sly, the ones I was going to get were HU252a, but yeah the number you gave look good if you want to go that way.

[ando76 4,354]

Well that's it. Only one way to work this out.  I'm going to back to back these extractors

 

 

with the modified (extended secondaries) pacemaker extractors

 

 

 

I've got on the burnout beast on the dyno.  I'll just modify the collector on the 6-3-1 extractors as it is god ugly.  Anyone want to lay bets????

 

 

[ando76 4,354]

So that's 2 out of 3 that run the 6-3-1, mind you wazzy's numbers are super impressive and his combination in Corty might go number 1 and through a smaller tail pipe is just freaky LOL

 

Hey don't forget Wazzy is running those numbers on a flat tappet camshaft!!!!! AND a car that is heavier (but not by much) than a bloody little corty with a roller cam. 

 

P.S I have met, spoken with and respect both Jason and Ken and their efforts.  One only has to look in street machine to see big dollar, big cube clevo's doing 10.7 to realise how quick these times are.

[matt_lamb_160 252]

And it is not because they have tried a 6-2-1 setup and it didn't work. My bet is if you added up all the fast 6s all over the world there would be more 6-2-1 setups. Both of the mentioned 6-3-1 setups were made by the same person.

 

No bets for me on the test as I recon not everything else will be equal about the two sets. Still be good to see though.

[TF_250 398]

Trust me ando wazzys engine in a cortina would kick all our asses.....LOL

 

Rob just go the custom route mate it would be a shame to put some off the shelf extractors on after all the custom work that has gone into the ute mate

[slydog 7,873]

Well your boy cant make em as he hadnt done em for a falcon and the guys I spoke to prefer and have results with the tri y's...so its looking like modded tri y's bruz.Bigger 2.25 secondarys 3.5 merge into twin 2.5.

 

Bet it will sound like ass but as long as it works.

[matt_lamb_160 252]

Sounds good to me. Twins won't though unless merged back into one after the mufflers, but the HP will be there and you will be making use of what you have.

[Clevo120Y 815]

I'm keen to see the tests also, no bets for me either for the same reason as Matt. I'm not trying to pick a fight or start an argument over the issue I just have my opinion and my reasons for it thats all. For a true comparison you would have to custom make both sets of headers to suit the same engine, you can't compare a generic set of one type to another as one set may suit an engine better than the other and vice versa.

Still keen to see your results Tony.

What are Wazzy's specs as that is flat out amazing, I haven't had the pleasure of reading about his combination.

[slydog 7,873]

Sounds good to me. Twins won't though unless merged back into one after the mufflers, but the HP will be there and you will be making use of what you have.

 

So the plan is the last part of the exhaust is the mufflers more or less that actually have tapered inlet and outlets (so more air speed tweaking) with a couple of 30degree tips that will finish at the rear valance either side of the number plate I'd say,but tucked up so there not visible.No 6cyl xflow sounds good if we are been honest but as long as it works I'll be able to live with it...maybe

[slydog 7,873]

I'm keen to see the tests also, no bets for me either for the same reason as Matt. I'm not trying to pick a fight or start an argument over the issue I just have my opinion and my reasons for it thats all. For a true comparison you would have to custom make both sets of headers to suit the same engine, you can't compare a generic set of one type to another as one set may suit an engine better than the other and vice versa.

Still keen to see your results Tony.

What are Wazzy's specs as that is flat out amazing, I haven't had the pleasure of reading about his combination.

 

Hey it's a forum bro and we will not all agree unless it's a question on how much of a cock XrGlen is...So keep your ideas coming,no one is forcing there views we are all discussing.Just shows how people do things differently to get the same results is all.This thread has opened alot of eyes about what works and what people use which was the hope/intention of the thread too...but it is still open to V8 turbo stuff so lets hope them boys join in too cos my ute is a boring POS to talk about for too long.

 

Wazzy's run a solid cam,don't actually know cam spec's but you would think 600 lift 275 duration atleast,I think it still runs Paceys and a 2.5"race exhaust?,head by Barbagello (yes the guy who doe's Pro Stock engines/cars) 13.5 mechanical injected 6"rod ACL slugs,crank trigger MSD 4600 stall 4.11 geared XE.Correct me if I got anything wrong Glenn.

 

Wazzy supplied my guide plates and tray (till I went custom sump which meant new tray) and a fuck load of knowledge.Very smart articulate man but still a QLDer so I can't rep him too much. 

[matt_lamb_160 252]

Absolutely. You have added heaps to the discussion Clevo.

 

Maybe Wazzy needs a custom set too, haha.

[wagoon 2,429]

A very general rule that I have seen work is longer primaries for hp and longer secondaries for torque, but the diameter of pipe is different for each setup. If you were to build an optimal setup for any crossflow wether it be 631 or 621 the size and lenght of pipe in each section should be different for each design anyway. But the test that Ando proposes would very helpful for someone wanting to buy off the shelf setup for a more mild engine.

As we all know it is what YOUR technical guru is comfortable with will produce the best results instead of mixing and matching different ideas. There is lots of fun ways to skin a cat

[Crazy2287 1,886]

Well that's it. Only one way to work this out.  I'm going to back to back these extractors

 

 

with the modified (extended secondaries) pacemaker extractors

 

 

 

I've got on the burnout beast on the dyno.  I'll just modify the collector on the 6-3-1 extractors as it is god ugly.  Anyone want to lay bets????

 

 

Right, i'm in cnts.

 

I'm putting my bets on the 6-2-1. As long as the pipe lengths evenly space the pulses 120 degrees apart it will offer more depression against the next event due to it being closer to the venturi peak when the next valve opens. and for the second merge as long as the phases are opposite. 

The angle of the merge collectors will also have a big effect on the amount of venturi caused and should not be overlooked, a well designed collector is an important part. Should be able to compare the effectiveness of the atcual merge at pipe sizes "x" and gas velocity "y"with a flow bench and a manometer... =P

[ando76 4,354]

Well I just made 334HP at 6000rpm with my modified set of pacemakers on a flat tappet cam so fuk it I'm not even bothering fitting the others.  LOL 

[slydog 7,873]

BAM...LOL

[ando76 4,354]

No I will do it when I have a little more time.  Essentially they are both off the shelf headers - I just extended the secondaries on the pacey's, I didn't up the size on them  - but I'm sure that there would be a gain there. 

 

The secondaries on the genies look a little under done to me and they are not pipe over cone.  perhaps I will convert them to pipe over cone and extend them to mate up to the existing system so we are comparing apples with apples.

 

But really as has already been pointed out this is only comparing them on my engine combo - not on anyone else's so yeah each to their own I guess. 

[Crazy2287 1,886]

Gimmie 100 of those horses immediately.

[Clevo120Y 815]

Bloody top result there Tony, you must be pumped.

[slydog 7,873]

Gimmie 100 of those horses immediately.

 

You...fuck off.Wouldn't use em anyway cos you have to rev it over 4500.

[ando76 4,354]

Gimmie 100 of those horses immediately.

I'm about to build another x-flow that I am calling 'the mad scientist engine'.  I'm using up some more parts off the bench and a decent engine I was given by Jason as part payment on his new race motor.

 

The bottom end has no-name flat tops at .040 and has a few balancing marks on the 250 rods but not on the crank as best as I can tell - It came with a lightened flywheel as well so I'm going to piece this all together with a crow 619 hydraulic I have here and some clevite anti-pump up lifters.  I'll do one of my sumps, oil pumps and I'll modify my girdle/tray at the front so that it can be used in a street car that runs a sway bar. 

 

Comp will be around 11:1 (I need to cc the head) and I reckon it would be a fun package making power from 2600-5500 so you may have to lift your RPM ceiling LOL. 

 

I'll do a build thread on it and then sell it at the end as I have seriously way too many x-flows here. Maybe I'll chuck it in the ute and run it in on the dyno and do the aforementioned extractor back to back comparison. 

[wagoon 2,429]

I retract my previous comment about Ando's comparison test for a more mild engine. Damn 334hp at 6000rpm is nothing near mild. Well done Ando, would be interesting to see what your serious engine produces.

[ando76 4,354]

yeah mate she is not a bad combination of parts old Bitza.  I'm half way through my serious engine build - my new roller cam speedway engine.  Now it will be something special. 

[ando76 4,354]

Did someone say x-flow with a twin system and x pipe???  Yes I am mad.


 

 

 

[ando76 4,354]

But not if it sounds half as tough as this...