The cosworth IM design is the closest to ITB w/o going ITB

I have seen a few go for under a grand on my350z.

But yea, def wait till it's all running and kinks worked out.

 

Since the Cosworth manifold is designed for RWD, the intake spout for the TB would require major surgery. I wonder if the air tunnels for each half of that manifold comes together in the spout? Kinda like the 3.5 elbow works?

 

That's why I was asking too.

Apparently their flow bench reads quite a bit higher then lol.

 

Looks like there is a vertical split instead of a horizontal split. You can see the crease go up to the neck.

 

So it might be possible to just shorten the spout a bit so that the TB opening is facing straight ahead?

Woops - it also requires a 350Z LIM - but I have a spare.... just have to port-match the the heads, again.

..

 

I would go with some ITB's for this build. You make an affordable set by using hayabusa throttle bodies.

 

OK - that sounds complicated..... ( I'd rather have the 'busa, but the wife...)

 

Yea it def looks like you can cut it and have it strait out.

 

It is rather complicated compared to buying an intake manifold. You could figure it out though.

Hood clearance might not be the best though lol.

 

Have any idea what the busa's throttle bore is? I've actually scrounged in eBay for bike carburetors, and see some occasionally, both singles and a group of four,

 

Good - then you get the job of figuring out how to get direct-port injection nozzles in that thing! Probably the closest I could get would be "under the covers" and "down the throat" of the intake runners.

I wonder how it would hold up to methanol, VP Racing's M5 blend.. ?? Probably melt something....

 

Cosworth manifold doesn't show good gains on an n/a build. Better gains with the factory manifld and a spacer.

 

I can believe that. The design looks like it would be pretty restrictive.


Also, I don't know what the busa throttles measure off the top of my head. They are probably somewhere around 40-45mm though.

 

Doh! You guys are right. But it looks like once he is in the 8k range, it will make the power up top over the spacer.

http://www.my350z.com/forum/intake-e...motordyne.html
It is very short runners so low end and mid is expected to have losses, but im sure a 150 shot will take care of that if the im produces up top


Boosted:
http://forums.nicoclub.com/injected-...m-t300785.html

I think you would get similar gains with nitrous.

 

Sure about that? Stock heads and cams, sure. But, with the whole package...

http://www.cosworthusa.com/store/pc/...nt%20tests.pdf

There appears to be a lot of HP gain with the Cosworth heads and ZK2 cams.... which is why i bought them. It's all about the breathing....

 

Stock heads, with stock cams flow around 300cfm. Cosworth are measuring at a much higher lift to get 346cfm(9mm valve lift Vs 10.5mm)
Big cams on stock heads and you getting a 10% gain in head flow for 16% more valve lift and thats not taking into account extra duration of aftermarket cams.

The most important bit in the cosworth graph is the 3rd harmonic appearing at over 10mm of lift, which with large lift cams has huge cylinder filling advantages.

I would use the Toyota 4AGE Black Top ITB's over Hayabusa ones.

 

Those are monster heads, and being CNCed from a Nissan casting, they are made within close tolerances. The ZK2 cams have 10.65mm lift, so they don't have the huge lifts some aftermarket cams do, but the combination appears to work well, especially using the Cosworth intake. Taking an otherwise stock 287HP 3.5 from 275 crank HP to 342 HP (at 7,500) is impressive - especially the top-end curve.

Do you think this is possible, or worth the effort? I know breathing is the key, but with nitrous, n/a power isn't everything.

 

Hmmm... I think that annular nitrous nozzles spraying down the individual runners from the side covers just might work. Since the individual runners don't seem to be accessible any other way..... Spraying through the TB is out - there's too many surfaces to keep the fuel from separating out, I think.


.

 

http://my350z.com/forum/na-builds/41...-build-14.html

Here's some proof. There's more in that section.

 

Here is a thread with some information on the Toyota Black Top ITBs. Looks like everyone except Nissan Maximas use ITBs.... However, at this point I don't want to consider using MAP.

http://www.mr2.com/forums/beams-owne...rts-lists.html

.

 

Hmmmm.... I see Hal's 9.34 sec street 350Z uses the Cosworth intake. Remember, I don't care about N/A results alone - nitrous has its own requirements...

Obviously more research is required.

http://www.the370z.com/injectedperfo...-34-video.html

And another link discussing spacers vs Cosworth with dynos and discussion...

http://my350z.com/forum/forced-induc...-rpm-fi-7.html

.

 

Well in that case then the cosworth is fine. For some reason people have good results with forced induction and not n/a.

Check out the sfr manifold. I gained 30whp at redline and 5whp peak.

 

http://www.nissanclub.com/forums/eng...no-tested.html

A little cheaper then the cosworth but you don't have to cut and weld.

 

But that's power over the fwd im. I wonder how it stacks up compared to a Z plenum

 

Just something for you guys to look at since we're on the topic of gaining/losing power with different IMs if you havent seen it yet. SGmotorsport did this experiment. The same guys who built that crazy long tube header design for the 350z. Basically more proof that to get the most power out of our VQs, ITBs are pretty much a must.

http://my350z.com/forum/na-builds/44...enum-test.html

http://my350z.com/forum/na-builds/46...ing-power.html

Of course these were N/A results though.

Contact NiZMo1o1 about the ITBs. They arent exactly cheap, but with the amount of money you spent on this build so far, it would be foolish to cheap out on one of the biggest bottlenecks on this VQ. The ITBs come nitrous ready by the way.

 

Damn, sounds like the VQ35 could really gain a lot by getting some big cams.
300cfm is insane for a stock head!!!

So COMPLETELY stock heads flow 346cfm at 10.5mm of lift? Like a stock head, no modifications?

Those would work too.
I don't think I would ever buy a kit, way to expensive.

 

Must. Go. Back. To. Kansas. Soon.

Another TX->KS->TX roadtrip is a must for me when this beast is finished.... The sound of that full 3" still haunts me the first time I heard it start up.

 

I didn't realize you had tested the SFR IM. The dyno charts are encouraging, but I wish you had tested the SSIM and the graphs showed RPM and not MPH - but hey, it was a noble effort, and very revealing. I think that I saw another member here that bought the latest SFR manifold, but I don't remember any test numbers - it looked good, though.

But - any IM built like the OEM version still has a long air path, and all have some restrictions because of that.

.

 

I love those guys - talk about thinking out of the box! I read those two threads twice - which isn't enough - and there is a lot of new ideas in there. It is all about breathing, isn't it? Lifting off the top plenum was classic!

Problem with the ITBs is that I'm sticking with a MAF for now, cause it is a street car, with power steering, AC, and all of the stock interior - not a hack job. ITBs are the ultimate in breathing, but difficult to figure out in a grocery-getter.....

 

I was thinking about letting you drive the car that day, but the primary nitrous fuel solenoid decided to act up. I probably wore it out. No one besides me has ever driven the car on the track.

.

 

I've been mapping the intake and exhaust cam actual timing - since I'm using a custom Stephen Max 3.0 gear setup with 0 degree advance - but I'm not done yet. However, I did find the cam card that Cosworth sent with the cams. Not much detail there... I really want to find out where timing is set.



I'll fill in the details soon.

 

The relatively large bore allows some big valves(for a Nissan multivalve) in combustion chamber. The valves are also very well deshrouded stock, whcih gives exceptional flow. For comparison, a Nissan SR20VE head flows close to 300CFM stock with smaller valves(albeit at larger lift values)

 

FWIW, this is the Cosworth combustion chamber. The volume is about 2 cc larger than stock, which makes my 11:1 CP pistons into 10.6:1 pistons... They use Inconel and stainless +1mm valves.



.

 

This is very good to hear. I want to build up an all motor VQ35 so badly and put it into a B13 sentra.

 

Since the engine still has a bell housing and starter attached, I decided to run a compression check on everything. I went down the left side and then down the right side in order 2-4-6-1-3-5, starting with 2. Cyl #2 was 180psi, then #4 was 160, then #6 was 140 !

What the heck? This engine sat for 6 months after final assembly, during the winter, with lots of lubricants, so nothing should have been dry.

Then I noticed that I had put wide paper tape over the LIM ports, but the first two ports were open to the air. Duh.... I pulled off the tape, and all cylinders were between 175 to 185 psi. Whew !

 

Lol musta scared the hell out of you at first.

 

Yeah, this blooper rated right up there with discovering cracks in my first set of Cosworth cams....

 

Haha, nice. What do you think is left?

 

I think it's time to schedule the installation.....

 

And it's done!

Before install:

http://i48.photobucket.com/albums/f2...0/DSCN1378.jpg

http://i48.photobucket.com/albums/f2...0/DSCN1379.jpg

After:



http://i48.photobucket.com/albums/f2...0/DSCN1383.jpg


It's been running since Thursday - had some exhaust surgery done, no cat now, bad O2 sensor, the usual install BS with EGR and idle module tied to the intake, still have a drip from the rear valve cover, but Oh My it runs nice... I may not need nitrous any more --- J/K. It explodes past 4K. But, I gotta drive it some before the abuse begins. (yes, the tape on the radiator hose is supposed to be there - the rest of the intake passes over the hose).



I made a couple of short videos, but the AVI files won't upload to the 'bucket.

.