More information! Been doing some digging and contacted Greg from Specialty Z as they are doing some deals at the moment on the 300degree rail, I asked specifically about the spray patterns and this is what he has said. If you have a look at the link there is some good information there, specifically this picture which compares a later model injecter against the older model in the same older head. There are some more pics here as well, these are from Mike Smith with similair testing. I have linked these in below. http://twinturbo.net/net/viewmsg.aspx?forum=general&msg_id=1667783 Courtesy of Mike Smith: 740cc 10ms PW 740cc 500ms PW new style 370cc 10ms PW new style 370cc 500ms PW Old style 370cc 10ms PW Old Style 370cc 500ms PW So based on these photos it looks like the stock later model injectors DO have a wider pattern BUT!! the later model 740cc's actually have a thinner spray pattern. So the question is, can we get these aftermarket rails made up to suit the 740cc injectors?
well done on finding that info you have helped my out there as soon ill need new injector to take advantage of my rebuild
Great find! Good to see UAS are spot on with the 740's... to answer your question YES they rails are currently being made up for nismo 740 items.
As far as spray patterns go, the older style 370cc @ 500ms PW looks to have a far better spray pattern than all the rest.
Curve ball here, But which injectors should I get for my 95 with the later model heads and lower plenum. It has the much larger fuel entry ports so I think a wider pattern item would be better but I dont want to think about so someone tell me which ones to get please
Well in theory yes a wider pattern should be OK but best and most productive bet would be to set up some similar tests once you have it in pieces
I didn't even go to that much trouble I just cut the flared ends of the stock inlet/outlet tubes and silver soldered -6AN weld nuts to them... easy twin in/twin out. I also used twin TT internal fuel pumps and utilised the no longer needed HICAS lines as the fuel feed, then the others as the return, through a nice big twin line fuel filter. This whole story about getting 500hp out of the stock setup is all good, except when you don't just want it for the 3 seconds on a dyno. You can never have too much fuel.
These photos DONT tell the entire story. If you look on the 90+ lower plenum. There is a capilary tube machined between the main air channel and the injector tunnel hole. These create a vaccum in the injector tunnel. This will significantly change the shape of the spray pattern by narrowing it. It's fine to look at pics of injectors firing into a can. But without the capillary working it isnt telling the entire story. I touched on this injector issue way back in the discussion of the SARD injector collars. I brought the protrusion of the injector through the fuel rail up and compared it to the "BORDER" rail that Method had. The " BORDER" rail IMO is a joke. The injectors don't protrude past the end of the fuel rail casting. There is no way the injectors engage in the feed tube. This creates the issue of the fuel actually hitting the tapered placement neck on the lower plenum before it goes down the hole. At least the Sards in the stock fuel rail, do indeed enter the lower plenum feed tube. Come back and show me pics of the spray pattern with the capilary pipe having compressed air fed through it while the injectors are spraying and you can put this to bed. :bash: The injectors HAVE to be tested when they are mounted in the lower plenum as the US pics show. A few too many assumptions ATM for my liking.
Don't worry graham the nismo injectors will be tested on a plennum before any conclusions are drawn. Also method has a border kit NOT the 300 degrees rail.
Edited " Border Kit" I am not worried at all. I machine tapered the Injector feed holes on my spare plenum and managed to taper the bottom of the hole up to twice its daimeter by the point where the spray enters the lower plenum. The Sards and collars should be fine then. The angle increase is about 10 degrees. So no issue for me
Better yet -vids! I am going to do similar with my lower plennum for better atomisation with nismo injectors. UAS are after a bolt-on soloution though which hopefully the nismos will provide... Sounds like you have given it a fair bit of thought though I'd love to see some pics of what you've done with it.
You can start providing all the modifications We send you plenum plus beer plus money and we get back plenum modified with fuel rails and injectors all sweet
The hole that leads from the Injectors to the where the fuel enters the plenum. Previously the hole was the same diameter from where the injector fits into the lower plenum. To where it enters the air flow. Mine is now tapered from the injector diameter where the injector exit nozzle is, and opens up to twice the diameter by the time it enters the air flow in to the head. The increase in angle is about 10 degrees over stock. This more than compensates for the increased fan width from the SARD injectors. I made a reamer that tapers from the finshed size to the Injector hole size and basically reamed the hole out. It wasnt too hard. Next time I am down the factory I will take some pics
Injectors (nismo 740cc) are in stock, rails and all lines and fittings are in stock (some of the Sydney guys saw them at dyno day) -only thing I'm waiting for is the vid. It's a bit tricky as not alot is being done with my motor until some more parts arrive so things like flow testing etc are all getting done in between more urgent jobs. I will send an email to john today and see if we can get it done over the weekend.
Update BAD NEWS Hi guys, got an update on the UAS rails and unfortunately it's not good. Andrew @ UAS did the trial fit and the rails just don't fit nicely -the injectors don't even sit flush in the rail. Very dissapointing to have to send these back to the manufacturer especially for UAS who have put so much time into testing and tweaking these to try and come up with an acceptable product. I've sent an email to Coz about group buy pricing on 300 degrees rails, who else is interested?
Possibly depending on timeframe I'm waiting to hear back from Street-to-Strip at the moment on pricing for the rails plus some other gear. He tends to have good contacts with Specialty Z so it might be worth while dropping him an email as well.
