Hi Guys,

I have ordered a Sirio EVO STI and need some advise from your guys

1) What for a break-in do you guys prefer

2) Which pipe combo works good for this engine? (I have the 2607 pipe, how
handels this picco pipe)

3) What is the difference btw. EVO4 - EVO4 STI (Only the blue print?)

4) Should I use only sirio plugs. Can I use picco plugs?

5) How about the sirio clutch combo. Is it must?

I would happy if any you guys help me.

thnx

Hi Guys,

I have ordered a Sirio EVO STI and need some advise from your guys

1) What for a break-in do you guys prefer

2) Which pipe combo works good for this engine? (I have the 2607 pipe, how
handels this picco pipe)

3) What is the difference btw. EVO4 - EVO4 STI (Only the blue print?)

4) Should I use only sirio plugs. Can I use picco plugs?

5) How about the sirio clutch combo. Is it must?

I would happy if any you guys help me.

thnx

I like using a break in stand.
Sirio 2611
I would use Sirio plugs if you can get them although I have been assured that the Picco plugs work well also.
Haven't tried the power clutch and I do not know anybody that has so I cannot comment.

Hi Scott,

how is the evo 4sti. I read from another thread that the bottom end of this engine not good enough is. some people wrote this engine has no power differences and is same as the evo 3 . Can you share your experiences.

thnx

Has the (evo 4) and (evo 4 STI) the same conrod? Can I use evo 3 conrods on the evo 4 sti?

thnx

I have not used one of these engines. One of my team mates runs this and I have raced against him more than once. It is a good engine. It does not have the bottom end that my IDM has, but nothing has bottom like the Picco based engines.

I've asked the exact same question to Mr.Rossi at the fay fair
Its a showoff prototype and it is fully functional and working

What should the head shimming be for the Evo 3 STI using 20% fuel?

.30mm of total head shim.

the only difference between the evo4 and the evo4sti is that the sti has ceramic bearings

and as for the conrods the conrod on the evo4 is lighter and has less material around the top connecting hole

also word is that sirio is going to change the material of there cranks they are getting rid of the black hard annodized crank in favour of a new material similar to what the novas use

Based that I have both motors the conrods are not the same you can use the Evo3 piston/sleeve/conrod in the Evo 4 but not mixed matched the sleeve is the same piston as well but the conrods are slightly different in height.
as for the Sirio power clutch it's all in driver preference the power clutch has the same feel for those that have tried the sp kyosho clutch or 2D/4D clutch set up is very similiar but the 3D to the power clutch settings are totally different. cranking down the spring tension on the sirio to 1.2 is to extreme the sirio spring height is taller than the kyosho spring & my spring collapsed very quickly I normally tighten it down from .5 -.8 range very smooth shifts spools up very quickly. Im very happy with it I also installed the Orion spring on the power clutch to make it a little more aggressive & shaved a 1/2 sec in lap times

GM, i did measure the sirio's spring but it is only 9.8mm compared to the kyosho's measured at 10mm some at 10.1mm. But there is a significant difference in the spring tension. Sirio's spring are much harder than the Kyosho's. On cranking the tension of the sirio's spring agree with you about the power it produces when tighthening more than 1.2mm. The power is too abrupt. My range is same as yours.

Doc wait till you try the orion spring it seems a bit more consistent
right now I am doing a little off-roading until the next on-road state race
running the Kyosho 777 WCE Buggy with the Kanai Evo 3/Sirio pipe this motor is ballastic after it started breaking in my buggy started to do wheelies on the straightaway I was like a little kid getting his favorite candy can't wait to run off-road again it is so much fun

GM, bro the orion spring can snug in nicely in the sirio's spring catch?

so far perfectly fit no srubbing