Honda vfr 400 nc30 hrc air tray???

[jasonmac87]

Was wondering would these be much use, I was going to make one out of sheet aluminium and put it on the nc30 for race use. Currently using stock filter and airbox but would like to try this. From what I am told either run stock airbox or remove it completely as anything in between causes problems! Has anyone any experience with this? Also on the retro racer link below it says a oil catch tank was fitted, any idea why this would be fitted and where it's fitted?

http://www.retroracers.com.au/2012/06/1 ... -air-tray/

http://akhara.com/nc30/nc30hrccarb/index.html

[Cammo]

I used to run full hrc open carbs on my race bike, they worked great on the track.




There's far more to it than just removing the airbox and fitting an air tray. You'll also need the hrc velocity stacks, emulsion tubes, pilot jets and jets. Slides if you can get some (same as nc24 carb slides).

Rick Oliver sells replica parts of all the hrc carb parts, his stock list is in the first thread here: viewforum.php?f=22

That's not a very impressive dyno result in the blog link in my opinion. It's been bodged up and doesn't appear to fuel too well either. There's easy gains to get if they set the carbs up properly rather than just taking off the airbox and putting massive main jets in.

An oil catch tank is fitted because a crankcase breather runs into the airbox (which is no longer there).

Ask away if you have any questions.

[Neosophist]

Agree with cammo, thats just been made to run without an airbox, not setup to airboxless style (which will give you some overall gains just sacrifice smoothness and "road friendliness"

It would make 60+hp with stock airbox and jets I think.

[jasonmac87]

I used to run full hrc open carbs on my race bike, they worked great on the track.




There's far more to it than just removing the airbox and fitting an air tray. You'll also need the hrc velocity stacks, emulsion tubes, pilot jets and jets. Slides if you can get some (same as nc24 carb slides).

Rick Oliver sells replica parts of all the hrc carb parts, his stock list is in the first thread here: viewforum.php?f=22

That's not a very impressive dyno result in the blog link in my opinion. It's been bodged up and doesn't appear to fuel too well either. There's easy gains to get if they set the carbs up properly rather than just taking off the airbox and putting massive main jets in.

An oil catch tank is fitted because a crankcase breather runs into the airbox (which is no longer there).

Ask away if you have any questions.

Cheers for the reply. I'm after looking at Rick Olivers page, look like most of what I'm after, would you know anywhere I could get the hrc air tray? Or even get the dimensions of it so I could make my own? Also could you tell me what diameter the holes are in the carb bracket?I have the drawing of it already but the sizes are hard to make out. My bike is running with a full mercury race exhaust system, ported/gas flowed heads, skimmed heads and standard head gasket so it's fairly high in compression, total loss ignition, carb slides drilled out to 2.5mm, I cut down the rubber bellmouths flush with the bottom of the carbs like the hrc, new valves and valve seats, has stock airbox and stock air filter, I think it's a bad job having the stock airbox in a way as the air scoop in the front of the airbox has a rubber flap directly underneath it so it's fairly obvious to say that fresh air has a harder route to make.
When you say the oil catch tank, do you just link the two pipes from the rear of the airbox into the oil catch tank?or do you have to return the oil back to the sump after this?any chance of a picture of what you have?I might have a better understanding then!
My bike is 66bhp at the moment, I reckon if I had the hrc air tray and the carbs set up properly to suit I might make 70bhp what do you think? Do you know much about the programmable cdi's that rick Oliver has ignictech I think, much of a benefit over the standard cdi and the black box speedo restrictor?
Sorry for all the questions bud, first year racing next year and I want to have the bike to it's max potential before I start.

[Cammo]

Running the hrc open carbs could net you a 2-4 hp gain at the top end perhaps.

Cutting the standard velocity stacks down is no substitute for the hrc stacks. If your air jets are exposed then it usually upsets midrange fuelling/running bigtime. Here's a pic of the proper hrc stack shrouding the air jet here:



Try sticking a wanted ad in the classifieds on the forum for the air tray. Genuine hrc trays are plastic and easier to fit than the fibreglass (or carbon) copies, but any type will do. My bro used to make them out of fibreglass, but it's a bit of stuffing around.

I no longer have my race nc30, Luke has a pic of similar oil catch tank in his race bike build thread, the whole thread is a good read if you're building up a racebike: viewtopic.php?f=62&t=30587&start=80

[Neosophist]

[quote="jasonmac87]My bike is 66bhp at the moment, I reckon if I had the hrc air tray and the carbs set up properly to suit I might make 70bhp what do you think? Do you know much about the programmable cdi's that rick Oliver has ignictech I think, much of a benefit over the standard cdi and the black box speedo restrictor?
Sorry for all the questions bud, first year racing next year and I want to have the bike to it's max potential before I start.[/quote]

What has been done to the bike? 66hp with just an open carb tray seems pretty rare / almost unbelievable unless its a really "friendly" dyno.

ignition box allows you to adjust the rpm and mapping, if you have hrc cams then its useful