Re: Daytona cams? K&N ? Turbo? Deaf?

[Eric Sheley <eric@xxxxxxxxxx>]

Well, my daughter is having a party for her 10th and the combination of 
preteens, Back Street Boys and toxic nail polish fumes have finally driven 
me from the living room to seek solace from the warm comforting glow of my 
laptop screen ......

I figured I will cover a few things in one email, so please excuse the length.

#1 - the Daytona parts insertion:

As David Arnett mentioned, the ST has steel liners and cast pistons while 
the Daytona has aluminum liners and forged pistons (The heads however are 
the same - only different on the old 509 and the new Tiger). It is probable 
that the Daytona piston has deeper valve pockets, so if you change to the 
Daytona cam, you would also need to change the pistons. The rods are 
different as well, but unless you are planning on racing, the ST rods 
should be up to the job. Then to get the most out of your top end, you 
would have to cut the exhaust balancers (crossovers) on the exhaust header 
and weld up the holes.

Then on to the EFI. Remember from our previous EFI lesson that the EFI 
tunes have to be mapped and designed to suit the engine design and the 
header/silencer design and flow. As Ross pointed out, look at the Speed 
Triple and Sprint - essentially the same engine specification, same headers 
but with different silencers, they flow very similar and have the same 
noise emissions but as they have different designs, they require 2 
different tunes. As he pointed out, they would not invest the time to 
develop such tunes if it were not absolutely necessary.

So, next would be loading the aftermarket ST tune (which throws more fuel 
through the system) and hope that it provides acceptable driveability and 
avoids detonation. If not, you would either be forced to remove all the 
parts you have just put in (plus add the balancers again) or move to the 
Daytona tune. Your fuel gauge would not work, and the malfunction indicator 
light (MIL) would probably remain illuminated constantly - and it may not 
work any better than the ST tune.

Since the ST makes (at the crank) 114-116 BHP with the performance pipe (or 
108 standard) and the Daytona makes 125, that's a lot of work to (possibly) 
get another 9-15 BHP max out of the motor.

# 2 - K&N

I'm not sure if K&N has produced a unit for the ST yet, but even so, it 
should provide no difference in performance. The stock paper filter element 
has been said to have a very high flow rate and that it does not restrict 
the breathing in any way. Also, there should be no gain from either 
changing the filter or even removing it as the EFI system has a pressure 
sensor between the filter and the throttle bodies - remapping the EFI 
depending on the air flow.

The system will even compensate for any pressure changes such as the slow 
blocking of  the filter as it comes to the end of it's service life (Via 
the air bypass system).

#3 - Turbo

The Turbo kit runs in the neighborhood of $5,000US. On the ST you should 
get around 150HP at the rear wheel. Brian at Turbo Connection has been 
making the kits for the T5 series for a couple of years and the kit itself 
is based on the popular AeroCharger which is the basis for a number of 
aftermarket kits.

#4 - (for David) No, you are not going deaf - stock setup is very quiet to 
meet all noise regulations that Triumph currently faces. The High 
performance can will open that up a little.

- - Eric


At 03:29 PM 08/05/1999 -0500, David Arnett wrote:
 >Keep in mind that the Daytona also has aluminum liners and forged pistons
 >(for higher RPM) application, for which those cams and fuel injection are
 >mapped for.  The Sprint has steel liners and cast pistons, which may not be
 >as well suited.  The Daytona may have different heads too, but I am not
 >sure.  I am interested in getting more power also, but I noticed that the
 >aftermarket does not have too much to offer at this time.  I haven't been
 >looking too hard, or actually not at all, but has anyone been able to get a
 >K&N air filter for the ST...or will one for a Daytona fit?  Does anyone know
 >what those turbo kits cost?  or if they are even reliable?   I figured I
 >would break the bike in nicely and get more used to the bike before hopping
 >it up.  I am bone stock right now, even down to the enormous silencer...or
 >maybe I have gone deaf, cause I can't hear the engine well at all with the
 >full-face brain bucket on.

 >>>> Jeff_Munsey wrote:
 >>Has any of the technically minded folks on this list
 >>considered how to seriously hop up a Sprint ST?  I know
 >>there is the turbo kit, but I'm curious about the
 >>possibility of stuffing the cams from a 955i Daytona
 >>into a Sprint St.  It seems as if doing this with a
 >>download of the Daytona tune should add ~20 HP to the
 >top end, (at the cost of some of the awesome midrange).


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