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R33 Suddenly Very Laggy - What Should I Test?

Aidan

By Aidan,
in Engines & Forced Induction

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mosquitocoils Veteran

mosquitocoils

Posted
Posted

If you've been playing around with double-clutching, along with all the before-mentioned symptoms I'd say your clutch is on the way out. You may have been burning it quite well while you were learning to double.

Aidan Contributor

Aidan

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Posted (edited)

@David

Car revs as normal, I was very sure whe boost was taking longer to spool, but that may have been my imagination. When the car was running, it took ages to build speed. But as I said in my last post, car is no longer working. Just sits there in first revving its heart out.

@Mosquito

Given the fact I've never had any issues with the clutch before now. I'd say I probably did stuff it while learning to double.

If the clutch is gone, should I go ahead and get my syncros replaced while the box is out?

Can anyone give me a ball park figure on getting my syncros replaced?

Cheers

Edited by Aidan
mosquitocoils Veteran

mosquitocoils

Posted
Posted

Id also say forget about the synchros, just get a new clutch. Exedy OEM replacement + labour goes aroun 600-800 total, roughly...

Or go for an Exedy Heavy Duty + labour maybe around 800-1000?

  • 2 weeks later...
Ryno Experienced

Ryno

Posted
Posted

If the turbo suddenly takes longer to spool up the issue could be a blocked/collapsed catalytic converter.

I had a hi flow metal cat that I bought through an SAU group buy a few years ago, that the insides collapsed and blocked up a few months ago.

The only symptoms were a slower spool up of the turbo, and my peak boost decreasing below what the EBC is supposed to maintain.

I thought the Boost controller was the issue, so I swapped that out, with the same results. So next I thought the wastegate could be the issue, and swapped that also. After this didn't fix the problem, I took off the cat and had a look. It was almost completely blocked due to the breakup of the stainless mesh inside.

It was a frustrating learning experience, as the cat would have been a pretty simple thing to initially check. I guess I figured when you spend good money on a stainless "Magic Cat" it should last more than 18 months.

Sorry to hear about your gearbox breakage, but while your fixing that issue, I'd also take the cat off and have a look inside.

Ruff Ryda Contributor

Ruff Ryda

Posted
Posted (edited)

Ahh double clutching should be more beneficial for your synchros but only if you do it right! If you rev too high and engage the clutch it will jump forward and put more strain on the drivetrain and too low will make pull it back similar to normal downshifting. The whole idea is to keep it smooth and get the revs matching right before engaging the gear. It should be seamless between downshifts.

Edited by Ruff Ryda

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