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Hello again so I blew my motor long story short one of the cams journals wasn’t getting oil and the cam stopped rotating and jumped timing on exhaust side. It’s a built r32 rb25de+t non vct so my questions are.

1. Can a r33 rb25det s1 head work on my r32 rb25de non vct block I still want to use it because forged internals. My r32 rb25 head is toast and I can’t find anyone with one.

2. Will my non vct parts work on the vct head which are cam gears, gear back plate, front gear cover, cas, cas bracket, and cams (rb20 tomei 256 cams). I will be deleting the vct because I don’t feel like it lol also I reached my hp goal on the dyno before it blew.
 

3.Last question I know I’ll have to switch up my manifold and fuel rail because no vct head is very similar to rb20 and ik vct head is different but I want to make sure that tps, water sensors, and idle air control valve connectors will be the same. I’ve read tps and water sensors should be the same just don’t know about the idle air control. I don’t want to have to modify my harness. 
 

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1 and 2 are fine (assuming the r32 rb25 was hydraulic lifter), but #3 I doubt there is much certainty because the r32 rb25 was a very rare beast, you might just have to see what fits and post back up afterwards.

15 hours ago, Duncan said:

1 and 2 are fine (assuming the r32 rb25 was hydraulic lifter), but #3 I doubt there is much certainty because the r32 rb25 was a very rare beast, you might just have to see what fits and post back up afterwards.

Yes still hydro and ok thanks for the information very helpful so I don’t have to source a new block and ok even if it doesn’t work I’ll just have the tuner change it to no iacv. 

  • 2 weeks later...
On 10/21/2024 at 3:31 PM, Duncan said:

1 and 2 are fine (assuming the r32 rb25 was hydraulic lifter), but #3 I doubt there is much certainty because the r32 rb25 was a very rare beast, you might just have to see what fits and post back up afterwards.

I forgot to ask as for deleting vct I’ll be plugging the solenoid but what about the vct feed from where the restrictor from the block would be. Weld the hole on the head shut? Or would it be fine just leaving it alone?

1 hour ago, Prof_Finesser said:

I forgot to ask as for deleting vct I’ll be plugging the solenoid but what about the vct feed from where the restrictor from the block would be. Weld the hole on the head shut? Or would it be fine just leaving it alone?

Have you got an RB25DE non VCT head gasket available.

 

Also, use the temp sensors from the car, particularly the one for the dashboard. They give different readings from R32 to R33.

 

As you'll likely need to tune this again, I'd recommend hooking up the VCT, even if there is no oil supply in your block, you can drill and tap and oil line the same way it is done for RB2530 builds. While it won't help with outright HP, it will majorly help you with low/mid range and make the car more drive able in lower RPMs.

 

If you don't have them already, you'll need new valve springs too, as the R32 RB25DE springs will end up too soft for boost.

2 hours ago, MBS206 said:

Have you got an RB25DE non VCT head gasket available.

 

Also, use the temp sensors from the car, particularly the one for the dashboard. They give different readings from R32 to R33.

 

As you'll likely need to tune this again, I'd recommend hooking up the VCT, even if there is no oil supply in your block, you can drill and tap and oil line the same way it is done for RB2530 builds. While it won't help with outright HP, it will majorly help you with low/mid range and make the car more drive able in lower RPMs.

 

If you don't have them already, you'll need new valve springs too, as the R32 RB25DE springs will end up too soft for boost.

I can use a rb25det HG that’s what was on it before and sealed fine. Yes I was gonna get it tuned again. For my springs I have a super tech kit on my non vct head I can use the retainers but I have to use different springs.  As for the vct I don’t want it as i have rb20 tomei cams and are different I rather just delete it all together and not have to buy a new intake cam. 

Edited by Prof_Finesser
16 hours ago, GTSBoy said:

Sell the Tomei cams to someone who is besotted with Jap brand stuff and get some nice New Zealand made cams that will work with VCT. That saves you the hassle of having to delete the VCT and gives a better result.

Is there something wrong with using tomei?  I’ve heard the tomei usa are fake parts. Reason why I don’t want to make vct work is one gotta make a plug for the solenoid get the vct cam gear. I rather just use the stuff I already have. I made 450 on 17psi full boost at 4K. I’m satisfied with that it’s a street car and sometimes hit the track for drift. If I’m really wanting to decrease the lag I’ll go to a smaller rear housing as I have an extra or even cam gears. 

3 minutes ago, Prof_Finesser said:

Is there something wrong with using tomei?

No, not really. Except that there are newer, better cam options that don't date back to the 90s.

I was under the impression that you couldn't use VCT with them, which is why I said to get rid of them. If you can't/won't use VCT because of what you listed above, that's another matter. Although I would have said the wiring aspect of it was something that you should just suck up and do, as it isn't hard. Getting an actuator for the cam gear will possibly be expensive.

I still say VCT is for the win. There's a reason HKS makes money selling it for 26s.

36 minutes ago, GTSBoy said:

No, not really. Except that there are newer, better cam options that don't date back to the 90s.

I was under the impression that you couldn't use VCT with them, which is why I said to get rid of them. If you can't/won't use VCT because of what you listed above, that's another matter. Although I would have said the wiring aspect of it was something that you should just suck up and do, as it isn't hard. Getting an actuator for the cam gear will possibly be expensive.

I still say VCT is for the win. There's a reason HKS makes money selling it for 26s.

Yea I know the wiring would be fine just want to use I got. This was my first built engine and it blowing got me beat down just want to have it running right again but hopefully I can find a non vct head so I don’t have to do any of this lol. 

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