Ariel.Club Forum

with a special dump valve pehaps ?

Dingo : you can increase the pressure a little bit +5 or 10% about with no problem if you do a re-mapping. You can win about 20 (engine) Hp.
It's not a good thing to go higher than that because, first of all, we have no air cooler on the SC Honda... and reliability will be very reduce. But ii's not what you are planning to do, so no problem. ;)

Has anyone invented a gearbox for superchargers that enables the level of boost to be varied, i.e. perform the equivalent of a pulley swap but without actually changing the pulleys ?

Ben

[quote="CalScot"]
[quote="dingo"]
Alignment appears to be OK. 
The belt is running at the outer edge of all pulleys and the inside of each pulley, not covered by belt is showing
by the same amount. 
[/quote]

Dingo, your in luck. Must be the clean living :angel:

[quote="maverick1"]
Dingo, since you have the Honda Atom why not just pick up a Rotrex kit and be done with it. With that kit you can have anywhere between 350-500hp and have the cool sound of a jet turbine.
If I had known what I know now, I would have opted for the Honda Atom.
Live and learn.
Cheersâ?¢
[/quote]

Mav,
I love my car but the whole mega power thing is a double edged sword. For example, I would not drive my car across country like you did unless I could line up high octane gas along the way (100 typically). If I run too lean, it's BOOM, and that line is very fine. My car is not as reliable as yours because it's on the edge! That extra adrenalin rush comes at a price which is more than just the $$$'s.
I think there is a lot to be said for more conventional NA engine upgrades in conjunction with moderate boost as opposed to just mega boost, which can be like grabbing a tiger by the tail in a never ending spiral of modifications.
I am trying to mitigate the reliability issue by the current round of upgrades it's now getting. Maybe I will be succesfull in getting mines tame enough to satisfy all of it. Maybe I will eventually end up with two Atoms. The current beast for the track and a new 300 for trips to the grocery store.  Only time will tell.


[/quote]
I hear you Cal but as you said in another post, with your setup you don't have to go all out and opt for 450+hp. You could easily use a different pulley or setup and [b]get 350 reliable HP[/b] and if you have a need for speed switch to a different one and up it to 400hp. And if that does not satisfy your need for speed you change some internals and add boost & a different tune for more HP. I like the fact that it's fairly easily upgradeable(this is subjective)....same exhaust and aftercooler etc.
I find it quite amazing that your engine has held up so far with those boost levels, and it was thrashed a lot at Atomfest.
Cheersâ?¢

Calscot,  I think you're double checking at some stage, but I thought I'd bring it up again in case. 
Sump baffle.
Then Mobil 1 0W 30 I think it is. Same as for Porsche 997.
and Redline 75W 90 gearbox oil.  None of these steps are going to gain hp, but may contribute to lopngevity \ less wear.
The baffle is an absolute must.

[quote="dingo"]
Alignment appears to be OK. 
The belt is running at the outer edge of all pulleys and the inside of each pulley, not covered by belt is showing
by the same amount. 
[/quote]

Dingo, your in luck. Must be the clean living :angel:

[quote="maverick1"]
Dingo, since you have the Honda Atom why not just pick up a Rotrex kit and be done with it. With that kit you can have anywhere between 350-500hp and have the cool sound of a jet turbine.
If I had known what I know now, I would have opted for the Honda Atom.
Live and learn.
Cheers™
[/quote]

Mav,
I love my car but the whole mega power thing is a double edged sword. For example, I would not drive my car across country like you did unless I could line up high octane gas along the way (100 typically). If I run too lean, it's BOOM, and that line is very fine. My car is not as reliable as yours because it's on the edge! That extra adrenalin rush comes at a price which is more than just the $$$'s.
I think there is a lot to be said for more conventional NA engine upgrades in conjunction with moderate boost as opposed to just mega boost, which can be like grabbing a tiger by the tail in a never ending spiral of modifications.
I am trying to mitigate the reliability issue by the current round of upgrades it's now getting. Maybe I will be succesfull in getting mines tame enough to satisfy all of it. Maybe I will eventually end up with two Atoms. The current beast for the track and a new 300 for trips to the grocery store.  Only time will tell.

Dingo, since you have the Honda Atom why not just pick up a Rotrex kit and be done with it. With that kit you can have anywhere between 350-500hp and have the cool sound of a jet turbine.
If I had known what I know now, I would have opted for the Honda Atom.
Live and learn.
Cheersâ?¢

Alignment appears to be OK. 
The belt is running at the outer edge of all pulleys and the inside of each pulley, not covered by belt is showing
by the same amount. 

The outer flanges are are different and can't be used I don't think, at least not on my S/C pulley.
The Rotrex S/C pulley is an 8PK. The Honda a 7, as noted before.
One final thing you will want to check is how Brammo mounted your S/C. Make sure they did not use a 6PK because the S/C is out of alignment with the engine belt path and the only thing to fit was the 6PK!
I hate to say it but there is a good chance they did that. Hope I am wrong!

Yes, 7 Pk = peak,  not counting the retaining flanges on outer extremes of pulley.

Dingo,
The S/C has a seven PK pulley, right? I forgot to ask that.
By the way, 7PK belts are not typical in these auto applications, so a good belt supplier will cut an 8PK down to a 7PK on a special cutter, so expect that as a matter of course.

Ah, but it was squeaking.  That was the first I'd heard it.  So all the better to swap it out.
I am pleased that the belts can be installed as it all passes under the right engine mount.
Yes 1203 mm is equal to 47.375 inches.
With a slighly smaller pulley, I'm planning to stick with the 1203mm length belt, but go up to 7 peak.
I'm hoping that with such a modest change in pulley size, that I wil not create any adverse effects.
There's no heat exchanger \ intercooler and the boost will be ~ 5% increased only, so the injectors should cope fine.
A little bit here, a little bit there. Might add up to something useful and it keeps me amused.

Dingo,
It' should'nt slip, cold or not. That tensioner on the Honda is a beast. If it's slipping, change the belt!
Your belt size will be 7PK 1203mm,  (assuming the belt was measured wiith the tensioner on at least 50% retraction on the spring) Something the factory should be able to get right, right?

Thanks for the observation.
That's what Brammo had offered too about the 6 rib one being adequate.

The belt was slipping for a short time while I was trying to video a bit of the startup and revving for a
YouTube posting.  Maybe the belt was cold.

I would feel better if it was right sized.  I'll check with local shops first than try belts for anything if unsuccessful.  Thanks, Peter.

Standard Honda Pullley is a 7pk (seven ribs) Running a 6pk on a seven ribbed pully is no problem by the way. It will last a little less and as long as it is not slipping, it's not an issue.
Try "Belts for anything"  [url=http://www.beltsforanything.com/site6.php]http://www.beltsforanything.com/site6.php[/url]
This is where I got the funky size for my Honda Rotrex kit.

Maybe I'll even crack 158.4 foot pounds torque ?
Hold ON !  Hondata ECU is the fully programmable one, so I'll try this slightly smaller pulley first without map change and take it
back to dyno folks and see what has transpired. 

This time, I'll be :
wearing my platform driving shoes,
plus the shims I put under the throttle pedal and also
(surprise surprise) those gains I got by taking up the throttle cable slack. 

Yes, truly a low tech series of HP gains.
The Exhaust and s\c pulley will benefit somewhat. 

Keen to find out.  Cut the conjecture, drop the hammer. 

OK, I got carried away, I guess.