Head work/ porting in progress

Should be done Friday hopefully

Pictures to follow

 

Head porting complete, heads re-assembled, new cams are fitted, decided to stay with standard STi V5 valve springs and sit with an 8000 RPM limit. New top hat underbucket shims are in to keep things in one piece. The heads will be on the engine by Friday.

New Baffled sump is also fitted

Things really starting to come together now

I have got pictures but I cant get them off my camera because my laptop has broken

 

A few images of the heads after the work.....



















New headstuds Have been installed and also the water pump.

 

Thats alittle tight

http://images.fotopic.net/?iid=yfpros&outx=500&oq=0

 

That was a just a tester pic, cant seem to link to fotopic images directly????

 

Some info that might be of interest....

4 parts to it links below...

http://mototuneusa.com/think_fast_intake_porting.htm

http://mototuneusa.com/homework.htm

http://mototuneusa.com/the_2007_superbike.htm

http://mototuneusa.com/super_sonic_nozzle.htm

Did this to a Nissan FJ20 turbo, gained 25kw mid range up to 5kw top end, gives you a ratio of the choke point of 65%, i used 70% first, then went 65%, made the same from 5000-7500, but gained 10 kw more at 4000rpm, weid, but it works

Michael

 

Interesting reading msgofast! My inactivity to port the heads has paid off again!

F

 

Wow. Spot on Conrad. Too big a port and the job is bug...... Far more important is the gas velocity and the porting to achieve that.

 

Depends on usaege I guess. A forced induction motor isnt going to rely on port velocity as much as a n/a engine would, so differences would be more pronounced between the two.
Port velocity will always make more torque low down ( assuming it can flow adequately too ), which is what most manufacturers will try to achieve. As for 99% of people thats the type of driving they do. Its also why Subaru swapped to a TD04, instead of the old TD05, which we all know to be better.

I dont think there are many competent head porters around, who dont take into consideration port velocties when doing work. At least if they didnt, they wouldnt be competent I guess.

There are many companies in the US making aftermarket headsfor V8's and thats one of the big selling points with the heads. They flow a lot more air, through better port design, but they do so with ports with a smaller volume that the std heads would have in a lot of cases. That means higher velocities. The heads are usually branded say 205cc for example. AFR 205cc is an LS1 head, with the 205 referring to the inlet runner volume. This is the same port volume as a std LS1 head, but it flows about 60cfm more at 0.600" lift. They produce superb results throughout.
So more air volume does usually mean more power/torque, but provided its not at the expense of air speed.

 

Thanks Harvey, he has made a luvvley job of the heads, taken ages but I am sure it will be worth the wait.

With regard to Motomans theory, our engine builder / tuner has actually commented on the OEM ports being too large in certain places as standard, nothing a bit of weld can't sort.

Update,

Heads on, new buckets installed, shims ground and installed, cams installed

Finally coming together

Next up, head to throttlebody adapters are being machined for Vac takeoff and Piranha nozzles.

Followed by measure up for final billet manifold design.

 

you running vac from each tb?

David

 

David, takeoff under each TB for balancing TB's

 

OK, heres a couple of pictures of the throttlebodies mounted on the Tuffnell adapters, Pirahna NOS nozzles can be seen mounted in the the throttlebody




Bigger Version



Bigger Version

 

Pictures updated

 

Conrad their a bit small mate

 

Conrad

I presume the injectors are "up stream" and if so does the butterfly not cause turbulance, or is that what you're after ?

Mark

 

Mark, first set of injectors are in the throttle bodies, if you look closely at the bottom of picture 1 (directly opposite Pirahna nozzle). 2nd set of injectors will be housed in new billet manifold firing directly down the barrel of the TB. The injectors will probably only be used on WOT anyway so butterflys wont interfere. Most modern motorcylcles use a similar approach.

Pirahna nozzle also points down to the ports despite entering the TB horizontally

 

Kevlar cam belt is on, cams are all timed up now with the vernier pulleys.

here's a picture of the exhaust ports, a little better picture than the last (brighter)



Larger Shot

and one of the cams in situ and the timing belt



Larger Shot

Conrad Ever closer we get

 

Hmmm they look familiar

 

Dave I Ended up buying another one... lol

 

A few more piccies....

Engine Front View



Bigger version

New Breather Adapters from.... the Racing line



Bigger version

Conrad

 

drop me a txt with how much for a pair of those

 

No prices yet m8 but will keep you in mind

 

Lol least i got a polished one

 

Swap me back, I'll give you the new one lol

 

conrad, this is going to be awesome.

But can I ask, if you are sticking to the 8k rev limit, how exactly are you going to chase the power output to make all this worthwhile when we know it can be done for less money?

Are you simply going to hope to get a shed load of torque, and if so, I guess you aren't worried about the bearings.

Either way, well done for doing this, it looks bloody amazing!

I wouldn't mind being considered for some of those adapters too!

Am more looking forward to seeing the throttle body controls, the balancers, the fuel rails and the piperwork to get from one turbo to 4 throttle bodies.

Keep it up

 

No thanx. Mines already on the car.



This engine sounds mad

 

Adam, thanks, rather than rushing things we are looking at alternatives to different parts along the way. The cam cover adapters was just one of them alternatives that was derived.

Phase 1 of new billet manifold was conceived yesterday (Friday) and drawings are being made up as we speak, a long process I feel but should be really trick in the end. We have also got some adapters at the drawing stages for people not wishing to go the four throttle body route but who want to use the new manifold.

As for the power output, we know of certain power figures against cost(your engine / Christians), but until we know what this engine will produce its difficult to know the benefits. With a turbo capable of around 800hp and N20 direct port Injection with jets upto 250 hp available then limits will be pushed. Bearings dont worry me, Porsche manage fine and theres arent any bigger. We will try the car on the rollers when finished with each set-up (4 throttle bodies & manifold and the manifold with head adapters & standard throttle body) will show the benefits or not of the new set-up.

I feel sure that the response from the engine with 4 x 54mm bodies and a large plenum of charge sat behind them is going to be extrodinary. Add to this a very capable DTA ECU priced at around £900 which is also a first on Imprezas.


Conrad

Quite exciting, cant wait myself.

 

Sounds really good Conrad hope it all goes to plan