6266 w/ schrick high lift cams

[Sticky]

I'll try to get the rpms up to 8k to get a baseline so we can really see what's happening when we swap cams, how much of an improvement they are.

This would be very, very useful.

[Flinchy]

I installed custom made pistons from CP to accommodate the increased valve lift D

Do factory pistons + high lift cams actually have clearance issues? I've been wondering this since they were released

[Tony@VargasTurboTech]

Do factory pistons + high lift cams actually have clearance issues? I've been wondering this since they were released

No

[Flinchy]

No

Thanks, I assumed they wouldn't

Even with larger valves?

[Sticky]

No

I thought we had a thread where someone said you have to change the pistons with certain cams?

[Ssphil]

Do factory pistons + high lift cams actually have clearance issues? I've been wondering this since they were released

If you look on VAC Motorsports website, they state that you need to upgrade to aftermarket pistons to get proper clearance for the increased valve lift. It also says on my piston spec sheet that they are specifically built to work with Schrick high-lift cams.

[Ssphil]

Alright so I had the opportunity to get the car out on the street to perform some testing and I have to say, it's not the same car anymore! I am very pleased with how the car drives (although the clutch is very stiff and not traffic-friendly LOL)

This is a map 1 pull and everything is up to my expectations. Can't wait to have this car dialed in!

[CobraMarty]

The increased high lift of the Intake valve occurs with piston at/near BDC. No issue here.

The increased high lift of the Exhaust valve occurs with piston at/near TDC. This could be a problem with valve to piston clearance.

[Sticky]

If you look on VAC Motorsports website, they state that you need to upgrade to aftermarket pistons to get proper clearance for the increased valve lift. It also says on my piston spec sheet that they are specifically built to work with Schrick high-lift cams.

This is what I was referencing, good post.

[Sticky]

This is a map 1 pull and everything is up to my expectations. Can't wait to have this car dialed in!

What are the specs?

[Ssphil]

What are the specs?

Which specs are you refering to?

[Ssphil]

Small update, I got in touch with a shop that owns a Dynojet dyno here in Quebec so I will be able to get my car there but it's not going to be until May. During that time, I'll be spending some time (and money) looking for upgraded axles to be ready for our first drag event in June. That new twin disc clutch and the MHD shift bog will destroy the OEM units in no time lol

[Ssphil]

Hey everyone, I just got back from the dyno and I am pretty happy with the results for now. I got 598whp from 91octane and meth, then I poured some MS109 race gas and turned up the boost and gave a few degrees of ignition advance and got 712whp from DI and meth. It is worth noting that I don't have port injection or any form of shotgun HPFP upgrade as of now, and it will probably be on the list for the next upgrade as my FPH was dropping and the trims and AFRs were rising.

I am equally impressed how the power seems to hold above 7k and not drop like some other dyno sheets I've seen. I believe valve springs might have something to do there but this only makes me excited to see what this engine will be able to do with high lift cams.

I have linked the dyno sheet and a video of my car in action.

[CobraMarty]

Nice.

So this is with stock head, stock valves, stock cams and upgraded valve springs.

What was the boost on 91 octane/598whp and 'more boost' on 109 octane/712whp?

[Ssphil]

Yes this is all stock except for the Supertech valve springs. As for the boost, the first pass was done on 24 psi and the second one was 32 but I had to lower it in the midrange because it would build boost so quickly the AFR would jump to 20 for half a second and then catch up, that’s why the torque seems low, I was able to get it close to 700wtq with a flat boost curve but I’d rather keep it safe.

[Payam@BMS]

Yes this is all stock except for the Supertech valve springs. As for the boost, the first pass was done on 24 psi and the second one was 32 but I had to lower it in the midrange because it would build boost so quickly the AFR would jump to 20 for half a second and then catch up, that’s why the torque seems low, I was able to get it close to 700wtq with a flat boost curve but I’d rather keep it safe.

When do you have your starting point for spraying meth?

[Ssphil]

14 psi IIRC

[maxnix]

Ported head makes a huge difference
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[Zdenek]

@Ssphil

can you help me? wanted to ask you where you ordered the pistons? Your pistons with compression 10.2 and machined for the high lift cams.
Greets Zdenek from Germany

[Sticky]

can you help me? wanted to ask you where you ordered the pistons? Your pistons with compression 10.2 and machined for the high lift cams.
Greets Zdenek from Germany

@Ssphil

[Zdenek]

Hello everyone, I have a question about the high lift cams. I've also called Schrick on the phone and written with Catcams, but nobody can tell me how much the valve pockets in the piston should be deeper. Schrick says they don't have to be deeper. But why do they have pockets when the valve is not extended at OT?
Greetings Zdenek

[Ssphil]

Hello,

sorry for the late answer, I ordered these pistons from VAC motorsport in the US.

[Zdenek]

OK thanks for the answer, I wrote to VAC right away. Need that measure by how much the valve pockets are lower, or a good price at VAC :-)

[Sticky]

OK thanks for the answer, I wrote to VAC right away. Need that measure by how much the valve pockets are lower, or a good price at VAC :-)

VAC has cams in stock too from what I understand.