Guys, I am going to install a V-AFC on my ITR and one of the things I'd like to do is raise my redline to 9k RPM. I am keeping my OEM camshafts (for now). I know that upgraded valve springs are a must with higher lift cams because of the added stress on the spring, but, what if I am only looking at a higher redline ?? I guess I know the answer to this question is to swap the springs and play it safe but I'd like to hear from your experiences.

 

You can't raise your redline with a V-AFC. You need to do work to the ECU.

I have heard that the stock valvetrain can handle 9000RPM without modification. But I have no experience with it.

Regards,

 

I was under the impression that the V-AFC would allow me to raise the redline... Guess I'll have to double-check.

My problem is that I've had a hard time finding an aftermarket ECU for my 2001 ITR. Sure, Mugen has its fabulous adapter harness for 2001 ECUs but its waaay too expensive for my taste. I also contacted Comptech and they tell me they have looked into adapting their ecu to use in a 2001 ITR but have not released anything yet. Any suggestions are welcome.

 

I think you can cut the rev limiter with VAFC, but then you risk engine damage.

 

kenji makes the adapters that your looking for. he is a member of this board, try im'n him on them. his are the only ones i would buy!

 

Staying with stock cams, it will be pointless to raise your rev limit.
Even with mild cams like a JUN1/2 or Toda Spec A.. you'll see peak power is below 8400rpm so you'll only be doing your engine harm by revving that high.

After 8000 with stock cams, the torque drops off like crazy, so you won't see much gain out of it.

But to answer your question.. stock ITR springs can handle 9000rpm. Not REPEATEDLY.. but if you zing it a few times you'lll be fine.

Install some Portflow inners if you're worried.. those are cheap and they work great.

But also keep in mind the parasitic loss of very stiff springs. You'll probably lose a few ponies.

 

TopSpeed Performance in naples florida sell the adapter, and the OBD 1 computers, its a great investment, it really helps to make your mods work for you.

And for you question, 8600rpms, is the absolute highest i would redline my car, the springs are not stiff enough for those RPS, just buy some PortFlow inner springs, move your inners now to the outers, and rev to 9000rpms all day long

 

give kenji a ring on the adapters...you can get ecu on partstrader.com

 

Stock springs are fine up to 9300-9500. The retainers are the weak area at
that point. That is why mugen says ITR doesnt need replacement springs
with their ECU.

 

Move your inners to the outers? I think you are confused, you would discard your stock inners if you are using Portflow inners. Personally I would just get the Portflow retainers and use the stock springs tho.