New project

[Jonnycoupe]

Its basically the same principals then as polishing and porting the intake and exhaust ports no? To increase the airflow and reduce air turbulence?

Thats focus'ed on getting air out of the engine, the exhaust manifold on a turbo should really be focus'ed on getting more fresh air INTO the engine.

 

[Wayn0r]

Thats focus'ed on getting air out of the engine, the exhaust manifold on a turbo should really be focus'ed on getting more fresh air INTO the engine.

but thats the same, your focusing on getting the exhaust gases into the turbo inlet as quickly as possible thus spooling up faster and pushing the air in?

 

[Simon]

but thats the same, your focusing on getting the exhaust gases into the turbo inlet as quickly as possible thus spooling up faster and pushing the air in?

You could make them hit the turbo really fast at low engine speeds by having small ports and narrow runs, however they could then choke at higher revs. So your lag will reduce but the engine will make less power

Porting and polishing means more cross sectional area in the ports and so for the same airflow you will have lower velocitys. So infact porting increases lag.

Manifold designs that have less backpressure mean that you cylinders have a higher VE so they produce more power as well as throw out more exhaust gases.

Thes comes onto Jonnys point about getting more air into the engine helps with lag.

It's quite complex though and requires more understanding that reading a forum and trying to digest as there are so many factors that effect it. We havent even got onto compressor or turbine maps, nor cam phasing. There are no set rules, a log manifold is generally crap. If you want less volume then you can design a tubular with that in mind.

 

[Jonnycoupe]

but thats the same, your focusing on getting the exhaust gases into the turbo inlet as quickly as possible thus spooling up faster and pushing the air in?

Without creating reversion issues no, your not trying to get the air as fast as possible. The higher restriction at the exhaust port would only serve to drive down cylinder VE. As you have combusted air/fuel not getting out aswell as it should. with no oxygen in it its simply inert gas taking up cylinder volume. You would have to reduce fuel to maintain a good AFR and inherant in reducing fuel is generally less power.

 

[Jonnycoupe]

but thats the same, your focusing on getting the exhaust gases into the turbo inlet as quickly as possible thus spooling up faster and pushing the air in?

Without creating reversion issues no, your not trying to get the air as fast as possible. The higher restriction at the exhaust port would only serve to drive down cylinder VE. As you have combusted air/fuel not getting out aswell as it should. with no oxygen in it its simply inert gas taking up cylinder volume. You would have to reduce fuel to maintain a good AFR and inherant in reducing fuel is generally less power.

 

[penski]

Looks like I need to go back to my books

I was of the understanding that the primary lengths of the example shown combined with the fact that they are right out in the airflow (reducing heat and therefore energy in the exhaust) would not be beneficial and that a 'log' (not just a box with four inlets and an outlet but rather one with divisions for a twin-scroll output) would be the better design. The example shown also looks to be quite convuluted....

*n

 

[Perywinkle]

Engine is in Spent a fun 2 hours driving round the industrial estate trying to find the correct pitch bolts to mate the cradle to the engine block lol

Stainless 4-2-1 manifold

Tank

Nice lightweight calipers

Alloy bodied 13 point protech shocks

Rad and asscociated plumbing tomorrow me thinks.
Torque resilient tube prop oredered.

So chuffed to be making progress after so long without funds

 

[Simon]

You can't devide a log manifold up for twinscroll though.

How do you make 1 and 4 pulse down the same 'scroll path'

 

[DingleBerry]

You swine, how dare you make progress! I've not even managed to get to my garage this week.

I have to say that's a nice looking project though. I intend to build one of these at some point, probably motor bike engined. We shall see.

I'll be watching this one though!

 

[Perywinkle]

Christ didn't realise how long it's been since I did something with the car

Picked it up again a couple of months ago now, after 2+ years of zero progress (lost interest and money lol)

Mechanicly finished, all plumbing and brakes done, wiring run throughout chassis, engine loom stripped back and redundant circuits cut out.

After a few days messing around trying to sort an elctric reverse, I bit the bullet and purchased a MNR reverse box (did nothing for my low cost build budget, but it's a stunning bit of work)

Found a cage going cheap a few weeks back too, so that's another bit that needs welding in now.

Paddle shift system seems to work a treat

It's a mess of wires atm, but as soon as the tank is fixed i'm gonna try and start it up

 

[BigglesPiP]

I like the shifter, will be interesting to see how well that works. Spent ages and 3 different designs before we could change gear in the SAE car.

 

[Perywinkle]

Yeah it's not been tested under load yet, so fingers crossed

 

[Jonny69]

Looks pretty mad!

 

[BigglesPiP]

Yeah it's not been tested under load yet, so fingers crossed

Should be easier with the engine running. SAE car was.

Lift off and smack it up the box clutchless, or are you going to fit a quick shift?
Clutchless downshifts are possible while you're rolling off the throttle, but that's rarely convenient unless you like suddenly pointing the other direction.

 

[Perywinkle]

Well it changes beautifuly atm up on it's stands.
I might invest in a flatshifter at some point for clutchless up and down shifts, ut for now it'll just be the paddles and clutchm (at least for down shifts)

 

[Perywinkle]

Wiring is almost finished
Engine turns over fine, everything fused and relayed up!

Popped a few panels on for fun

Cage getting welded in next week, then proper fitting of panels.

 

[Morba]

Longest project ever! Will be great once done though

 

[Perywinkle]

I dunno, some of the guys on the locost builders forum are 10 years and counting, so 5 aint too bad
It'll be finished by crimbo, as to whether or not it'll be IVA'd by then is another thing, they'll probably find plenty of bit i've forgot about that are non compliant.

Want to try and get it weighed soon to see what it's turned out at, can't be too much over estimates yet as I can still lift either end off the ground.

 

[Fr0dders]

Want to try and get it weighed soon to see what it's turned out at, can't be too much over estimates yet as I can still lift either end off the ground.

lol epic

I'd pay to see peoples faces if you got out of the car in the supermarket and lifted the car about in the parking space to get it straight

 

[Aero]

Not spotted this before but it looks cracking, will be interested to see it when its finished

Cheeky question but what is the rough estimated cost for this build?