Pop goes the BRZ. Advice please. UPDATE

[DaiTT500]

http://www.power-division.com/produc...cat=414&page=1

These are the GSC springs I got.

[Xero-Limit]

Originally Posted by Draco-REX

Do you have a part number? I see two sets from GSC, but I didn't notice a mention of beehive.

Also, I'm still at the stock redvline. Any downsides I should be knowledgeable about?

Thanks.

The cheaper one is the standard kit, the more expensive one (400-500) is what Dai got below and includes the beehive springs. Beehive spring setups are superior in racing use where you are prolonged at high rpm. For most people the cheaper kit is plenty to keep the rockers from getting banged up.

[Draco-REX]

Originally Posted by moto-mike

The cheaper one is the standard kit, the more expensive one (400-500) is what Dai got below and includes the beehive springs. Beehive spring setups are superior in racing use where you are prolonged at high rpm. For most people the cheaper kit is plenty to keep the rockers from getting banged up.

Thanks. Ordered and on the way.

[chaoskaze]

Such a nice read, this reminds me starting from 2015 model subaru actually changed the valve & part of the head, the new valve is actually longer (from 103.3mm to 105mm). Would that have anything to do with this?

[Draco-REX]

Originally Posted by chaoskaze

Such a nice read, this reminds me starting from 2015 model subaru actually changed the valve & part of the head, the new valve is actually longer (from 103.3mm to 105mm). Would that have anything to do with this?

Don't know. It's possible the longer valve would make it less likely it would lose touch with the rocker. Depends on what other changes were made.

[chaoskaze]

Originally Posted by Draco-REX

Don't know. It's possible the longer valve would make it less likely it would lose touch with the rocker. Depends on what other changes were made.

Looked around & found this. http://www.ft86club.com/forums/showp...&postcount=642

looks like other then valve & cam/cam gear, rocker is also changed. Maybe some other parts as well in steps.

[matchamochi]

Originally Posted by moto-mike

The cheaper one is the standard kit, the more expensive one (400-500) is what Dai got below and includes the beehive springs. Beehive spring setups are superior in racing use where you are prolonged at high rpm. For most people the cheaper kit is plenty to keep the rockers from getting banged up.

If people decide to go S/C route do you feel like upgraded springs (and possibly rockers) are a requirement for safety?

These pictures are giving me nightmares.

[ATL BRZ]

Originally Posted by matchamochi

If people decide to go S/C route do you feel like upgraded springs (and possibly rockers) are a requirement for safety?

These pictures are giving me nightmares.

Debating this as well.

[Draco-REX]

Originally Posted by matchamochi

If people decide to go S/C route do you feel like upgraded springs (and possibly rockers) are a requirement for safety?

These pictures are giving me nightmares.

Originally Posted by ATL BRZ

Debating this as well.

I noticed that the spring descriptions said they were for various levels of boost. I'm not sure how that works since I would think that higher cylinder pressures would only help the springs. But I'm sure there's a good reason. That being the case, then springs on a boosted motor (definitely pre '15 according to the above post) would seem to be a good idea. However, with the sheer number of boosted twins that are running just fine without valvetrain issues, I don't think it would be an immediate concern. Maybe an off-season upgrade?

[DaiTT500]

It's just randomly being unlucky my opinion.

[Draco-REX]

Originally Posted by DaiTT500

It's just randomly being unlucky my opinion.

Let's hope I'll reduce the randomness to near 0.

[GsxrMe]

Originally Posted by Draco-REX

I noticed that the spring descriptions said they were for various levels of boost. I'm not sure how that works since I would think that higher cylinder pressures would only help the springs. But I'm sure there's a good reason. That being the case, then springs on a boosted motor (definitely pre '15 according to the above post) would seem to be a good idea. However, with the sheer number of boosted twins that are running just fine without valvetrain issues, I don't think it would be an immediate concern. Maybe an off-season upgrade?

I personally removed my check valve on my pcv passenger side and have a tiny cone filter on both engine pcv to vent to atmosphere. I plugged the the hole on the intake with a vacuum plug with clamp.

I think if you get boost into the engine and it creates a back pressure on the valve, the valve will float. The piston will kiss the valve and the valve will throw the rocker to the moon. the tube from intake to passenger pcv. When under boost the tube now has boost. The pcv is closed. The only pcv that can open is the front near the ac. That doesn't seem good the rear passenger pcv is unable to let boost out and can cause back pressure.

[Draco-REX]

Well, the plan of getting a used head and building it with better springs fell through. Of the 4 used heads I found: one was listed twice and turned out to be damaged, I couldn't get a hold of the salvage yard of the second one, and the third when it showed up was from a FA20DIT. When I called the yard about the mixup they tried to convince me it was out of a BRZ and sent pictures of the car as if that meant something. The car was obviously flood damaged so I didn't bother to try and get the correct head from them.

At this point I had to look into other options. 1. build a new head, 2. buy a set of built heads. Pricing out option #1, building a single head and having a shop change the springs on the other, it turned out to be a significant portion of the cost of buying a pair of built heads. So I decided to go with the built heads.

Finally, they were delivered today:

Full Blown Motorsports Stage 2 heads.


Ferrea hardware including dual springs, titanium retainers, Comp Plus valves, seals, etc.



Shiny new valves. Exhaust valves at 1mm over-sized. Also FBM performed their "Competition Valve Job".

And a full P&P:

Exhaust.


Intake.


Can't wait to get these on! These, plus the Delicious 9.0 tune, should make for some pretty good numbers. Unfortunately, it will probably be Spring by the time I can get the car on a dyno.

[GsxrMe]

i assuming since I don't see aftermarket rockers. The factory rockers are fine if the valves are shimmed correctly?