Individual Throttle Bodies and Improved Airflow

[Dessertrunner]

Here is a link to were I have posted some of the converion of the mill. Not much for posting but you can see the machine.
http://www.cnczone.com/forums/knee_v...ch_3000_a.html

Tony

[Dessertrunner]

Here are two possiable ways for the twin rollers to turn I would like comments over which direction is better, my guess is the airflow at lower revs will be better with one of the designs. So which one. The PDF are 3d so you can rotate.
Tony

[dynomatt]

The pictures I've seen of roller setups have them running in opposite directions.

M

[Dessertrunner]

I thought that to Matt, talking to a few guys that have seen them on road car have said at part throttle they were terriable that's why I was wondering if they would be better the same direction. I think it maybe a case of getting your mate to bench test the 2 and figure which one gives the best over different throttle openings.
Tony

[oab_au]

Originally Posted by Dessertrunner

I thought that to Matt, talking to a few guys that have seen them on road car have said at part throttle they were terriable that's why I was wondering if they would be better the same direction. I think it maybe a case of getting your mate to bench test the 2 and figure which one gives the best over different throttle openings.
Tony

The only thing that I can see is that at part throttle the air flow should be aimed at the injector side of the tract to help with atomization, as large injectors are probably used.
That is if they are below the throttles, and not on top.

Harvey.

[Dessertrunner]

Matt had passed on to me Marks suggestion last year when we did the bench flow test that Mark beleived we should reduce the inlet diameter throught the roller throttle body from the current 45mm to 40mm. The logic being that we would keep the air speed up going into the head, also that it might help with the low end torque that Harvey has mentioned. So on that basis I will do the first set with 40mm on the top. (If its a bad idea I can enlarge them later)

Have finished a trial milled port it looks good and have sorted the CNC Gcode. Hope to start the throttle bodies this afternoon.
Tony

[oab_au]

You have not wasted any time, since we talked about in Tumut. The mill looks the goods, I know you will work the code out OK.
Good inlet air velocity, makes for good combustion at low engine speeds.

Harvey.

[Boxersix]

Originally Posted by Dessertrunner

Here is a interesting picture of a F1 roller throttle. It has twin rollers.
Tony

Twin roller throttle have been how I've made all m ITB roller setups. the overall size of the throttle can be kept smaller vs a comparable sized single roller. It's just a little bit more complicated with gearing and spacing(working off existing available gears that is) and just packaging, but works far better.

Good luck with the cnc mill be warry not to crash tooling. Get's expensive.

Also, do yourself a favor and buy a pro tram double indicator squaring setup. Knee mills can have a tendency to drop a couple though along their long table axis. This tool will help you keep the head as squared as possible and is one of my most favorite tools in the CNC bin Have one for every machine here.

IIRC, ebay sell them for under $100 and they come with the dial indicators.


yup, here: http://cgi.ebay.com/Pro-Tram-Square-...item3a63ee5440

[Boxersix]

Originally Posted by Dessertrunner

Here is a interesting picture of a F1 roller throttle. It has twin rollers.
Tony

Twin roller throttle have been how I've made all m ITB roller setups. the overall size of the throttle can be kept smaller vs a comparable sized single roller. It's just a little bit more complicated with gearing and spacing(working off existing available gears that is) and just packaging, but works far better.

Good luck with the cnc mill be warry not to crash tooling. Get's expensive.

Also, do yourself a favor and buy a pro tram double indicator squaring setup. Knee mills can have a tendency to drop a couple though along their long table axis. This tool will help you keep the head as squared as possible and is one of my most favorite tools in the CNC bin Have one for every machine here.

Buy it direct from Edge Technology Products, or IIRC, ebay sells them for under $100 and they come with the dial indicators.


yup, here: http://cgi.ebay.com/Pro-Tram-Square-...item3a63ee5440

[Dessertrunner]

Hi Adam,
I had looked at that guage but wasn't sure if it worked good to see it does.

Have been trying to figure out how to do the ram pipes, Matt looked for 90 degree ones and didn't have any luck so while sorting out throttle body I will use short straight to start with.
Have cut the intake ports on the roller bodie. Need to send them out for line boring for the roller. Still undecided as to location of the injector so need to decide that soon. I was thinking of using dual injectors have 1 low for slow speed and the other high for higher revs.
Was considering using dual SVX injector as I have plenty of them.

Have been looking at the head and figure I would like to be able to do the head work using the mill. It might mean building a jig to hold the head at the right angle to enable the ballnose cutter to get in but I think it will be worth the effort.

Here are a couple of photos.
Tony

[Boxersix]

It's a very handy indicator tool, and even if your head is trammed in properly, it's still excellent and accurate for parallelism of the material or machined parts into your bed vise(s)

Well with the money spent. Their squaring tool is nice too. I have used their tool height setter, but now have digital touchoffs for all my machines.

[Dessertrunner]

I have been thinking about the point you made Adam about keeping the rollers free and that to do that I may have to do each cylinder individualy. My problem is I can't quite get my head around this design, questions like how do I attach each roller throttle body to the head and how best to manage the linkage come to mind.
I have got to be honest and say the more I consider your suggestion to more I like it, it kind of grows on me. Currently getting the throttle bodies line bored is expensive so there would be a big saving on that cost. Once I have sorted the individual throttle bodie design out they should be quick and cheap to make which is another big advantage. Thinking this over further due to the reduced cost we should be able to experiment with different port designs a lot more.
Okay I am conviced just need to think single unit and I should be right.
Thanks for the suggestions.

I have sent a email to these guys asking details to see if there ram intake will do the job for me 90 degree ram pipe.

http://www.jenvey.co.uk/home/accesso...ed-ah42x160x88


Have a great day all.
Tony

[Dessertrunner]

Okay here is a draft first go of the single throttle body,
Tony

[Boxersix]

It's definitely going to take some inginuity and tinkering. Some have done it via couplers(like a spigot design in how snomobile carbs are attached) or vband to a premounted flange.

With the use of individual throttle units you do eliminate much of the potential bind, but you should still machine out to a close tolerance, then use a boring head in your mill to achieve the final dimension and bore finish. With converging bores, you'll be taking out only a thou or two per pass at that point.

I've attached some screen capture shot of the Solidworks CAD assembly of the R34GTR roller throttle I made for a customer not long ago. 100mm, 1.2% taper bore, fully bearing supported and shafts seals, v-band connections on both ends.

[Dessertrunner]

Looks good Adam, its a great help. Do I understand correctly that the V band is fitted on the two green wheels.
How did it work out?
Tony