extending the rev limiter??

[Anonymous]

anyone thought about setting the limiter to 8k? i was thinking that a N/A 1ZZ with an 8k redline  s:twisted: :twisted: s:twisted:   cant be as stressfull on the engine as a turbo'd 1ZZ.

Can the limiter be changed by a piggy back ECU? and would the ECU be able to bring more power and by taking advantage of the extra 1k revs?

[mph]

Simply, mechanical stresses so different as that can't be compared in any meaningful way. For example, if I were raising the rev limit the first thing I'd look at is changing the valve springs; for the turbo, I'd be keeping an eye on the con rods and big-end bearings.

The unichip as fitted to mine won't be able to effect the rev limiter; I would imagine that the eManage with full harness probably can - best check with the rest of the guys though..

[markiii]

and in terms of getting a benefit from raising you rev limit, cams now become the limiting factor

[Anonymous]

The e-manage is capable of raising the revs. You need to enter into it the correct input that affects the limiter, and then cap the voltage with it, so the main ecu never sees it, don't think it's going to make a huge diffference as the 1zz's highest power band is lower down than it's current rev limit.

The PFC is really the way to go if raising the revs is your goal.

A turbo on a 1zz isn't really stressfull if your power gains your after are quite low. Myself and Martin have been turbo'd for over a year now and (touch wood) have had no engine problems. I couldn't imagine life without the whistle behind my ears now!!!

[Tem]

anyone thought about setting the limiter to 8k? i was thinking that a N/A 1ZZ with an 8k redline  s:twisted: :twisted: s:twisted:   cant be as stressfull on the engine as a turbo'd 1ZZ.

Can the limiter be changed by a piggy back ECU? and would the ECU be able to bring more power and by taking advantage of the extra 1k revs?

FWIW, MWR mentioned that 7400rpm should be safe with stock internals.

You won't gain anything with higher rev limit though. The max power comes before 6500rpm and the power starts falling fast after it:
My stock dyno

[Anonymous]

tem: by looking at a that graph, it bloody does fall fast! i was expecting the engine to lose all of its torque anyway, which is why i asked if a piggyback ECU could maybe smooth it out a bit?

it would be nice to have a larger rev range as you wouldnt have to change up so soon when racing   s:twisted: :twisted: s:twisted:   (on the track of course  s:wink: :wink: s:wink:  )

I suppose you would really need to upgrade the cams to harness some more power?

[mph]

Cams would help, but only so much. The long stroke is great for mid-range torque but become less efficient higher up the rev range.

[Tem]

if a piggyback ECU could maybe smooth it out a bit?

Piggyback should be able to do the same as for example PFC:
 m http://monkeywrenchracing.com/cgi-bin/i ... rfc1zz.jpg m

(you can use the search to find mph's NA Unichip dyno  s;) s;) )

[juansolo]

Revs kill engines as a rule.   If you're raising the rev limit you'll need to look at whether the bottom end can take it.  At the very least you might have to swap out the rod bolts for stronger items.  Then to actually make any use from this you'd have to have cams made up to utilise the extra revs as the standard one's are not likely to be designed to produce power over the standard limit.  Then you may have valve issues and may need to look at abandoning springs altogether and going for solid lifters or what have you.   Don't know the standard N/A tuning route you would take on one of these engines, sorry.  Now if you want to fit a N/A Cosworth YB or a 2.0 Vauxhall XE I could probably help.

Getting substantial power gains out of an engine is rarely simple and never cheap.  N/A is probably the most expensive way of all.

In summary: wait for the TTE Turbo.

[Anonymous]

Valves, Rods, Pistons, and a PnP and a side order of cams would make raising the rev limiter worth it.