ZE top end solution

[verm69]

Hey hey!

well it's closing in on the time when i get to actually spend copious amounts of money on my car to get it going!

but before it does there will me a new worked head going on... so... i was wandering what you guys reckon would solve the top end power problems of the ZE, as i may as well do it while the new head is off.

i've herd talk of adjustable cam gears, but i'm wandering if there is anything else that would help to solve it. Weather it be mild cams, new springs and adjustable gears or what ever.

if so... what degree and lift cams would everyone recommend? and so forth.

it's a map small port ze running about 10-12pound.

thanks for your help in advance

cheers

dave :P

[stefan]

check tech articles and see what all the turbo guys are doing

[rthy]

Ze top end will never be good with a supercharger cos of all the belt slip,

my old one would use to slip around 6500 but power from 2000-6500 was enough to give v8 a heart attack - lol

[Hen is a total nutcase]

It's not belt slip that is the problem (it can be fixed).

Simply the design of the Toyota supercharger doesn't like particularly high RPM, and gets inefficient when the engine is reved hard. Also the intake design is pretty crappy.

A bigger throttle body and a mild cam increase (even just the "bigport" cams) will help things. But if you want a really screaming top end then you need to ditch the SC or put in some serious work sorting the setup right out.

Hen

[dr1ft-pig]

bigger cams should do the job, you will need harder springs aswell, and if you wanna fine tune them get adjustabe gears

[Justo]

it's a little thing that most map 4agzes get.
it's known as the 5500 rpm power drop as this is when it normally happens.
one way to fix the problem is to get an aftermarket computer.
or a cheaper option just accept that it happens and don't rev it past that point.
you probly have peak power by 6000rpm anyway unless you got big cams.

there are heaps of posts on www.twincam.org

[rthy]

what if the stock sc12 was replaced with a sc14 or twinscrew?

[Justo]

I havent done either these so not too sure.
but from what I understand youll probly need a new computer if running more than 14psi on the stock computer.
I have read a rew sc14 -> 4agze articals and they mostly run a diff computer.

there was a guy in the states making a twinscrew kit for ze powered mr2's and he was getting great results.

here is some links I have found along my searchings

http://www.members.westnet.com.au/adsport/sc14fit/

http://www.ae86drivingclub.com.au/forum/index...249&hl=sc14 (http://www.ae86drivingclub.com.au/forum/index.php?showtopic=10249&hl=sc14)

http://www.ae86drivingclub.com.au/forum/index...530&hl=sc14 (http://www.ae86drivingclub.com.au/forum/index.php?showtopic=530&hl=sc14)

[verm69]

sweet thanks guys...

I thought so, just wanted to confirm


I have an aftermarket computer installed, and I'm pretty sure the head thats going to go on has bigport cams. but would big prot cams be enough? I'm thinking about getting some cams and better valve springs, but I'm not sure witch degree and duration to get... I don't want them that big that I have to idle at 1200 to keep it going, but I want them to help solve the top end problems

what would you all sugest... I'm a noob when it comes to cam specs and stuff :lol:

thanks for all the help boys!

[verm69]

oh yeah, and I know the sc12 is a relatively small blower, but I don't want to put a sc14 in and thought that working the head some more would be an easier solution.


thanks again boys!

[Justo]

I'd stick with the bigport cams. thats what I'm buying now. the 4agze is not ment to be a high rever is a torque'y midrange beast.
then I'll be getting the ports opened up to fit camry valves and a bit of matching to a smallport plenum and I'll use the throttle after the sc.
I'm not too sure if I'll need a new computer but I've seen a setup like this before and the sc sound is awesome. it's really loud and whiney.

[DavisJD]

I don't have any top end power problems with mine, (Freshly rebuilt, aftermarket ecu, front mounted intercooler, extractors, exhaust).

it's a steady power rise to 6500rpm, then stays at peak power until just after 7000rpm.

Just trying to point out that there isn't really major top end problems if it's set up properly.

Goodluck with it.

[verm69]

yeah, I think if the computer is tuned properly it'll probably solve it, but I was thinking while I have the head out, I may as well do some more to it! especially in reguards to the top end...

I pretty much want to work the head a little more, and am looking for suggestions for what cams I should use...

[86sp]

Have you driven it yet with the aftermarket computer? You shouldnt have any probs with top end dropping off. Mine only started leveling off around 7000rpm and made 122rwkw with stock boost.. The power drop at 5500rpm that people speak of is a standard computer thing.