Sam's build thread

[sambb]

Wait your in the fatherland! at the ring. cool

[sambb]

The Australian hillclimb titles were just on at Panorama. A mate in a Crx B16 who normally runs in road reg was there. He got down to a 55.60 which isn't hanging around at 57.00 mins , 4:04 and 6:25hr. The sunday was wet which should have some nice scary slides

YouTube here' dry Saturday.

[sambb]

For sheer mentalness, check out these runs by two of the quickest openwheelers in the country. They were over 260km/h across the top apparently. Malcolm Oastlers run in the yellow OMS is just mental:

https://youtu.be/CUvLoOKbYUw?t=10503

[sambb]

More small port to large port injector/mani stuff:


So small port mani runner left, large port on right. In the pics, the bottom of the pic is actually the top of the runner. You can see that the small port injector position aims the injector towards the bottom edge of the flange. However I'm pretty sure that the stock 315cc small port injectors have an upward angle on their spray patterns ie the fuel stream tilts up towards the connector side of the injector at say 10 degrees and that is what (despite the axis of the injector body) allows the fuel to go down the centre of the runner.
The large port runner is different however. The injector axis is towards the roof of the runner and has those weird bulbous bits either side of it. The OEM injectors all use a dual cone so these shots must just clear these bulbous humps which are used I guess for starting to split the air into 3 paths for the three valves. But for that to work the original full length EV1 injectors used in AEB large port headed engines, must have been straight angled cones yeah? I cant find info anywhere to confirm that. Looking at it I just cant see how if the early EV1's used a 10 degree upward slant to their fuel cones, how it would have cleared the runner and not just wet down the roof of the inlet port. Can anyone help on that??
Now what worries me is this video: https://www.youtube.com/watch?v=6evgEvOXDfY
In the vid is my exact part number EV14 Bosch 550's and you can see that in side view they have the same 10 degree or so upward slant to the fuel stream that small port injectors are said to have. That's why they come recommended as an injector upgrade for small port motors but how appropriate they are for large port motors given the completely different runners, I dont know. I'm really worried that this is just not going to work on a large port runner and that a straight shot is needed. I contacted those Pro Boost engineering guys that did the vid and they were awesome and said that an extended tip Porsche 997 turbo Bosch EV14 627cc injector would work better but I really dont want to retune for bigger injectors again. Staying 550cc would be so much easier/cheaper.

so today I fitted my 3/4 to full length top injector hats to take the small port injectors out to the correct length for a large port mani. You can see the difference when fitted in the fuel rail. One thing I noticed is that the EV14's actually have a 5-6mm end tip length to them. In addition to that the actual injector face of the nozzle is nearly flush yet in the OE small port injectors the nozzle is about 3mm recessed. So in effect relative to the OE small port injectors the EV14's place the face of the injector nozzle at least 8mm closer. And in addition to that, the large port mani positions the injectors 10mm closer to the head than the small port mani. So all up the EV14's when installed in the large port mani will have the nozzle face say 10 + 8mm= 18mm closer to the valves - so kind of an extended tip already I'm thinking. You can see the tip protruding proud out of the bottom of the injector cup in the pics. You can see in the last couple of pics that despite the injector nozzle protruding more than I thought it would, that it still looks like the fuel could be running too close to the roof of the runner/port especially if my injectors turn out to have an upward slant to the fuel spray.
So what I need to do is confirm
1. does anyone know if the early large port EV1 injectors were a straight shot or if it was angled like the small port ones apparently are. If they were angled too, then all ggod, mine will work especially since they run with a pseudo extended nozzle face.
2. I'm thinking to be certain of my injectors I need to get them on an injector dyno to see if they are offset angled. It'd be ideal if an EV14 could be set up in installed into the large port mani and fired to see if the fuel shot comes out through the runner correctly. Anyone done this?
Large port to small port mani conversion = not as straight forward as it would first seem.

[sambb]

So the ports shown in the pic are of a large port head. The second pic shows cutaways of what I think is a large port vs small port head.The spray geometry pic shows how the factory uses dual cone spray. The spray axis are aimed at the back of the outside two valves. The middle valve doesn't get a direct shot, it gets the shoulder of the adjacent two. I asked Pro Boost engineering about that (not getting why a single cone wouldn't work better for a 3 valve inlet) and they said that when you actually flow bench the head, the centre inlet valve actually flows much lower than the outside ones which is why it is done this way. They said you need dual cone because there's no other way to get a wide spread to suit that wide oblong shaped port. The side view would have to be of a small port mani ie the injector axis points at the BOTTOM of the runner but they get around it by having a upward angled spray. The large port runner/injector mount is not like this as the injector axis looks at the TOP of the runner.

BUT when looking at the cutaways of the ports you can see that the large port is much curved around the top compared to the small port which runs flatter and lower inside the head. That's why I think the injector in the large port mani's aims higher in the runner but I'm worried it'll be too high if I use an up angled injector when I'm not meant to.

[Sydneykid]

Probably an opportune time to point out that if you went to E85 it wouldn't matter much what the spray pattern is because ethanol atomises so much better than petrol. eg; at 100 degrees C injector temp Ethanol atomises (wider & less dense spray pattern) ~20% better then petrol. Then add the additional ~25% E85 required and we end up with a ~45% improvement in atomisation and spread at engine operating temperatures. It's not all good news (when is it ever), at say 20 degrees C E85 is 30% worse than petrol. Hence why it takes some tuning to get the cold start and run nice.


Cheers
Gary

[sambb]

Thanks Gary. I noticed the other day that the United in Dee Why near me has E85 andso too does one around the corner from work. At this point the only thing hlding me back from going E85 (other a few fuel hardware mods) is the difficulty in getting it tuned on my budget. I've been doing the remote tune thing and from what he and others have said it can be difficult to get thigs precise that way when dealing with E85 due to the large amounts of timing at different loads etc

Aside from that and related to the dual cone spray that the OE/EV14 injectors do, the middle of the 3 valves (the one that pro-boost said flows the least) is also much more retarded by way its cam lobe and runs lower lift (0.6mm smaller measured from base circle to lobe tip) compared to the outside two valves. Whether this is by design to induce two counter swirls in the combustion chamber or just due to mechanics as that middle valve runs very close to the bore wall and has a fly cut in the piston for it, I'm not sure, but could be why dual cone is the go with the 3 valve like it is for a 2 valve inlet.

[Sydneykid]

The 2 x United's on Rookwood Road are my sources for a race meeting at Eastern Creek, and the United at Minto on the way to Wakefield. The mixture is pretty easy to tune, I just change to 25% larger injectors, leave the duration the same, maybe up the fuel pressure a little and fine tune from there. Timing is trickier though, I can always add quite a bit which makes a difference to the power output but an even bigger difference to the response. Often I can add 10 degrees and 15 is not unheard of, that's where you need the flexibility in the ECU.

I use Rochester injectors disk/multec style, Mark who builds the race engine prefers Bosch Motorsport. Completely different styles but they both work OK.

Personally I think spray pattern is more of an emissions thing than being horsepower related.

Cheers
Gary

[sambb]

I chose the 550's as they would give me head room at 3bar and even more at 4 bar. I'll double check with the tuner guy but I'm pretty sure they were going to be E85 flow capable at 3 bar with the TFSI turbo off a Golf mk6 Gti. Any bigger and I'd have to go to a 4 bar regulator probably. I think 4 bar would over stress my current fuel pump which is a poor mans deatschwerks copy but a DW165 is on the cards anyway and that's an E85 capable pump yeah. I definitely like the idea of cooler burn negating the need for water/meth injection. Not so much the idea of stressing about fuel locations, how fast the needle will go down in traffic on a 40L tank and probably always running around with a jerry can in the boot - although there's always a water meth reservoir there now anyway which could go. I'll think hard on it for sure.

[Sydneykid]

Just roughly, 100cc of injector flow enables around 13 bhp on Pump98 (using 80% duty). So 550 x 4 x 13 / 100 = 286 bhp. Divide that by 1.25 for E85 = 229 bhp. Commonly we pick up around 10% with E85 tuning, so around 252 bhp. Is that your target range?

In my experience the injector flow rate increase isn't linear with a fuel pressure increase (ie; a 33% increase in fuel pressure doesn't give a 33% increase in fuel flow). It's very injector relative, some handle the higher pressure and give a reasonable increase, some don't, plus their spray pattern falls apart.

Is there an adjustable fuel pressure regulator that you can use? That way you can sneak up on the pressure which can also be a help in tuning around limitations of the ECU/software.


Cheers
Gary