Cams, ITB's and a supercharger....excessive, cool, or pointless?

[Rhys Beal]

I already have Jenvey 45mm ITB's and GT cams (428 profile). Would adding a rotrex be pointless me having the ITB's or would it just be even better?


...Also, if the Rotrex and ITB's do work, will trumpet length play as big a part as a N/A engine? I have both 90mm and 120mm trumpets

 

[MartinR]

I have no idea if they would work well together but it would be mental as f**k and bloody quick

 

[Dan519]

throttle response is always a good improvement from having ITB's. Induction length is always important on any setup

 

[Rhys Beal]

Thanks Dan.

Will it also mean that because I already have mod's in place that should see around 205bhp I will therefore require less boost to hit the same bhp as if I had standard inlet and cams? Ideally I would like 260bhp, is this okay on a standard bottom end?

 

[Dan519]

you won't be hitting that power, bit under 200 on ITB's and those cams normally.

only limitation you have is detonation and revs. I'd keep to a 7.2k limiter personally. Revs kill rods, detonation kills pistons.

All you can do is map it and see what it manages to make.

 

[Sam@NP]

That would be a rad setup!

 

[Daniel]

you won't be hitting that power, bit under 200 on ITB's and those cams normally.

only limitation you have is detonation and revs. I'd keep to a 7.2k limiter personally. Revs kill rods, detonation kills pistons.

All you can do is map it and see what it manages to make.

Curiosity kills cats.

 

[Bobby.]

Sounds like an epic idea and I don't think it's ever been done on a f4r. Well I've never heard of/seen it.

 

[Dan519]

Sounds like an epic idea and I don't think it's ever been done on a f4r. Well I've never heard of/seen it.

It was started but never finished some years ago.

 

[Bobby.]

It was started but never finished some years ago.

By who?

 

[Joe#]

Ktec did it on there 182 iirc? It would be soo mental though!

 

[Dan519]

By who?

ben_p's ph1 was meant to have it done. I'm talking 4-5 years ago

 

[Dan519]

Ktec did it on there 182 iirc? It would be soo mental though!

nah, that's turbo'd, and just used the ITB casings with the butterflys removed

 

[Jay_Kay]

K-tec are making a itb turbo aren't they?

The silver ph1 thats on their facebook.

 

[Joe#]

nah, that's turbo'd, and just used the ITB casings with the butterflys removed

Oh right. That was a pretty impressive build to be fair.

 

[SharkyUK]

Funnily enough this is the setup I was looking at but was warned that it would be a nightmare to map and getting the ITB's to play nicely with the boosted setup would be troublesome. The recommendation was to sell the ITB's and go back to the standard airbox / inlet setup. As a result I've now started down the forged engine route but still not completely ruled out a 'charger of some sort.

 

[SBV116]

ben_p's ph1 was meant to have it done. I'm talking 4-5 years ago

Who was doing that?...........

 

[dmallett]

Do it Rhys.

 

[Rhys Beal]

Do it Rhys.

Okay

 

[dmallett]

Would an rs2 inlet not be better suited to this? As its simpler.

Excuse me if im wrong.

 

[Rhys Beal]

No idea mate. All I can say is that I already have the ITB's and buying an RS2 would probably cost more than what I can sell the ITB's for

 

[Rhys Beal]

Funnily enough this is the setup I was looking at but was warned that it would be a nightmare to map and getting the ITB's to play nicely with the boosted setup would be troublesome. The recommendation was to sell the ITB's and go back to the standard airbox / inlet setup. As a result I've now started down the forged engine route but still not completely ruled out a 'charger of some sort.

How do supercharged bikes get on then? I read on Jenvey's site that they are capable of handling upto 6bar! I plan to run 0.5bar

 

[JackJack]

Curiosity kills cats.

De cat mate.

 

[Gray]

Who was doing that?...........

That same person who was 'doing' your ITB set-up a few years ago...

 

[Dan519]

How do supercharged bikes get on then? I read on Jenvey's site that they are capable of handling upto 6bar! I plan to run 0.5bar

mapping and getting stable sensor readings gets tricky. you have to use trick pipework, or change to alternative mapping strategies like boost correction (uses a throttle based map, and adds a straight % of fuel on a boost pressure scale.

 

[Rhys Beal]

mapping and getting stable sensor readings gets tricky. you have to use trick pipework, or change to alternative mapping strategies like boost correction (uses a throttle based map, and adds a straight % of fuel on a boost pressure scale.

Sounds complex.....doable though Dan?

 

[Dan519]

yeah it's do-able. are you thinking of using the Jenvey turbo plenum?

 

[Rhys Beal]

Was going to use something that I can seal really. Fancy mapping it?

 

[Rhys Beal]

Also I know you don't like them Dan but would an Omex ecu suffice for this setup? Reason being is I already have an Omex loom

 

[Dan519]

Call me to talk about it properly at some point

 

[Rhys Beal]

Call me to talk about it properly at some point

Will do later this week

 

[Bobby.]

De cat mate.

Very good.

 

[Chip-mk1]

With the supercharger providing such a consistant amount of boost at any given RPM, its actually far simple to map multithrottle on an ITB setup with a charger than it is with a turbo.

Wont really effect your peak power by much, as you say it will just allow you to hit the same thing at a psi or two less (efficiency is good ), but can help with throttle response slightly.

If you want the efficiency gains with the complexity then just remove the throttle plates and fit a shared plenum with a single throttle, this is how I have done similar in the past:

you wont get the gains in throttle response, but like I said they will be tiny anyway so not really losing much.

 

[domsclio182]

Sell itbs, buy a supercharger or turbo set up. I have had my 438s removed from my supercharged engine due to the engine being at its very limits for standard internals. Will be going back in when the engine is forged.

 

[Chip-mk1]

Would an rs2 inlet not be better suited to this? As its simpler.

Excuse me if im wrong.

RS2 inlet would be ideal for a boost application, but you would need to alter the fittings in it potentially as they are push fit for sensors.

 

[Dan@SJM]

K-Tec used to glue them in.

 

[Chip-mk1]

K-Tec used to glue them in.

Well, thats cheap and I guess it works, but not the way I personally would aim to do it TBH

 

[Dan@SJM]

Guess Its handy when a sensor fails and you can't change it.

 

[Chip-mk1]

Yeah exactly. But there we go, some people want the cheapest solution not the correct one.

 

[Dan@SJM]

I suupose aslong as you can get a sensor where the calibration is the same as the OEM one, you could fit a bolt in one?