BP6D high Comp, 7500 rev ITB
 

I am starting a build of my BP6D, high compression and ITB, my goals are a reliable street car that once a week I can race hard with a limit of 7500 rpm, I have already bought some things, I would like your opinion.

I currently have:

- Piston OEM, 10.5
- Piston Ring OEM
- Conrods Maxpeedingrods
- Main and Rod Bearing ACL Race
- Flywheel Fidanza Lightweight 1.6
- Clutch 1.6 OEM
- Crankshaft (balanced set)
- Header Raceland
- ITB 4AGE Silvertop
- Adaptronic PnP ECU- Mishimoto Radiator

It is in plans only if necessary:

- Boundary S2 Oil Pump
- Reroute Coolant
- Volvo Spring

I don't know what else I could add to the list or remove from the list.

I didn't realize that there was a 10.5 factory 1.6 piston.

What fuel are you planning on using?

I would use the boundary oil pump for a couple of reasons. One so you don't have to worry about it coming apart. Two so that you gain more oil volume.

It is a BP6D VVT engine, the pistons are OEM JDM, I plan to use 93 gasoline for the moment, the pump gears would be the VVT ​​with 2 shims.

I think he’s just using a 1.6 clutch and flywheel. I wasn’t aware there were any 10.5:1 factory pistons made though? Am I missing something? Ah, JDM pistons. Carry on.

I believe Supermiata recommends SUB lifters for aggressive use above 7,500rpm and upgraded valve springs on BP6D motors above 7,800rpm. You’re slightly under the hard limit there, but these might be worth considering for peace of mind since you’re still close.

Why do you think you need two shims?

From what I have read, it is the configuration that comes with the VVT ​​BE oil pump, in the future I am going to incorporate an external oil cooler.

Do you know that it does not mean that you will have higher oil pressure all the time? You often only see oil going over relief pressure when running at high RPMs when the engine is still cold. The pressure at operating temperature will often not be changed.

I worry that it puts additional wear on the oil pump when warming up. Maybe I'm unfounded in these thoughts.

If revving the VVT past the stock redline of 6900 for any period of time I would not use the stock springs if I can avoid it by rules.
SUBs adds more confidence (no shims to spit out and lighter).
Rebuilds after a dropped valve is not the most fun you can have.

Yes, the goal is to reach 7500-7750 rpm, the Volvo or ST springs from what I have read will be essential as well as the Boundary pump.

To be fair, the oil pump is probably the most well-lubricated part in the engine. So it's probably fine. I think high crankshaft flexure is when the gears see peak loading.

My thought on oil pressure is that it should scale with max RPM. The factory oil pressure is fine for factory redline. But as you go higher, more can be beneficial. For ~2L engines, the rule of thumb of 10 psi per 1k RPMs is a good rule IMO. Also, I bet I'm not following this. And I have absolutely had bearing wear problems above 8,600 RPMs, so that may very well be why.

What work will you do to the head and block? 10.5 pistons on their own won't really make it 'high' compression. You really need to squish that space harder skimming the block and the head. It seems like a lot of work for not actually making much power using stockish bunch of stuff.

With ITB's I'd anticipate the power band being fairly high in the rev range and it might feel a bit lacking until youre into the upper range. As much as it reduces cool factor for ITB's, a well designed airbox with a longer tract will help with that.

I plan to make a shave to the head of 0.060, to increase the compression, as mentioned after the engine is mounted, the box for the ITB would be excellent with a pipe from the front, I am still wondering whether to remove it from the fog light or Put in a small radiator and remove the front outlet.

If you're running the stock cams, I'd save money on the SUBs and only do upgraded valve springs. I rev my BP4W out to 7500 on the street and occasionally 7800 at autocross and it's been fine. Given I am running stock cams, double heavy valve springs from ST, but also 26 psi of boost. Without the boost, the single spring would be sufficient or double light if you ever think you might go to a more aggressive camshaft. You can run a mild camshaft without SUBs but if you go to the wild side SUBs and the double light valve springs are probably required. Also, when I was in the market of rebuilding my engine, I couldn't find Volvo springs, so keep that in mind. Supertech might be your only real option.

Also, a minor porting to the short side radius on the head's ports would likely be beneficial. Just don't go too crazy with the port size/volume, you can kill any hopes of decent low-end power that way.

edit 2, from the Fab9 store:
There are three options to choose from depending on your usage:

Single spring - 8000rpm
Light double spring - 8400rpm
Heavy double spring - revs to 9000rpm

(small note from me, keep in mind a more aggressive cam will lower these numbers)

The numbers on the heavy doubles seem right to me. I've been to 9K on heavy doubles probably 100 times without subs. But had a problem one time and went to 9,300 and it did tag a few valves, but didn't spit any shims. These were with stock cams at the time.