EDIT *** please disregard what I said earlier. Don't know where my head is tonight. Getting frustrated, still waiting on the car to be finished



BTW, I would do suspension first also . . . if you are planning ahead for more mods. If you just want to win your local class and need 2 seconds per lap to do that, tires are your best bet . . .

 

Definitions are given in 12.13 and 12.14

12.13 BLOW-OFF VALVE (BOV) / POP-OFF VALVE (POV)

A device intended to limit maximum boost pressure in the engine
inlet system by opening to vent the inlet system to the outside atmosphere
when a preset boost value is reached.

12.14 COMPRESSOR BYPASS VALVE (CBV)

A device intended to allow a supercharger or turbocharger’s compressor
output to recirculate back to the supercharger or turbocharger
inlet when the throttle plate is closed. The purpose of this
recirculation is to reduce boost lag when the throttle plate is reopened.
A CBV is referenced to intake manifold vacuum and opens
when manifold vacuum exceeds a preset value. It is closed under
boost. CBVs installed by OEMs operate as described above. Some
aftermarket CBVs vent to the atmosphere, and are marketed as Blow
Off Valves or Pop Off Valves, although their operation is otherwise

identical to the OEM CBVs.

15.10.c.4.e) Compressor bypass valves (CBVs) are considered part of
the air intake system, and may be replaced or updated/
backdated independently of the other components of a

forced induction system.

Well I guess you can use any CBV you want. We are both proven wrong.

Anyone know if Wastegate actuator can be modified in SP?? Is it considered part of the turbo or part of boost control system?

 

I've checked into this extensively. The stock Evo does not have a "blow-off valve". It has a compressor bypass valve, as described in your quote from the SCCA rules, below. You can replace the compressor bypass valve with any other bypass valve, but you can't put in a blowoff valve whose purpose is to limit maximum boost. So, in particular, you can replace the cheap-*** plastic Evo 8 bypass valve with the metal Evo 9 part, which I have done. Less leakage, more boost.

The waste-gate, on the other hand, is built into the turbo housing and is therefore part of the turbo. The rules clearly state that you can't update the turbo from an Evo 8 to an Evo 9 without updating the entire engine. (I may be doing exactly that, since I blew a rod bearing on my Evo 8 engine.)

Anyway, all you BSP guys with an Evo 8 who installed the 10.5 hot-side are technically illegal, as far as I know. But IANAL. :-)

Mike

 

EDIT *** thanks for clearing that up!

 

The wastegate actuator, spring, etc. is part of the boost control system. You can't modify the wastegate itself, but since our turbo is internally wastegated, you can't really do anything to it anyway.

Part f) allows changes to the wastegate actuator. The actuator is a mechanical part of the boost control system.

 

You are correct, the actuator is part of the control system, not the turbo and can be modified under BSP rules.

Preload adjustments or/and adding an external spring (BTW one of the best power mods I've done as it reduces boost tapering substantially) to control how fast the flapper opens and closes should all be legal for BSP.

 

This is where I get confused, granted I do run SM so it doesn't matter, but I want clarification.

You state above, you can't update the turbo from an 8 to a 9 without updating the entire engine...fair enough.

Your last paragrapch, all you Evo8 guys who installed the 10.5 hotside are illegal. The 05 Evo's are Evo VIII and came with a 10.5 hotside. So its sort of contradictory what your are saying. Can you clarify?

 

If that's true, then I guess maybe you could update an '04 Evo engine+turbo to an '05 Evo engine+turbo. If the '05 Evo engine and the '04 Evo engine are identical, or close enough that one can be converted to the other using non-update/backdate SP provisions, then it should be fine -- in other words, the update to the '05 engine won't require an actual engine swap.

 

^ Correct. Engine specs from '04 and '05 are the same save for the hotside of the turbo. Therefore, changing an '04 to a 10.5 hotside is all that is necessary to make the whole engine unit match the '05 specs. Right? Or am I missing something else?

Now to go to the '06 turbo you would have to swap to '06 engine specs, which include the MIVEC head/cams/ecu. Anything else different between the MIVEC and non-MIVEC motor?

 

I know at a minimum there are cam timing changes between the 03 an 05's, as well as the turbo change.

John

 

cam timing is allowed to be adjusted on a non-mivec motor. unless you mean the cams are actually different duration or lift.

 

technically you are supposed to take out you 03-04 motor and install the 05 with the 10.5 hotside. If you are willing to get the documentation that proves NOTHING else is different between the 2 motors, then you might win a protest. the real question is: is there enough power gained switching housings to be worth the hassle.

 

Yes, pistons are also completely different. It's 3 ring design (03-05) vs 2 ring design (06) and I believe coolant passages are also different due to MIVEC.

 

I understand why the rules are the way they are, one being keeping costs contained. However the whole update backdate thing is a bit screwy. You can change the entire motor to a new one but not the turbo??? If you want to keep the cars equal allow update/backdate more freely. It seems like you should be able to update/backdate or not. Has anyone put a IX motor in an VIII evo? Aren't there a host of issues like ACD, ECU, etc?

 

According to what I've heard, e.g. from chris@jztuning.com, you just need the ECU, wiring harness and long block + turbo, to do the upgrade from an 8 to a 9. I guess the lack of an ACD is not a problem. (Is that controlled by the ECU, or does it have it's own built-in electronics?)