aftermarket camshafts and factory ECU

[benzo]

I have a pair of HKS 264-degree/8.1mm lift inlet/exhaust cams (and TRD adjustable sprockets) for my Kouki Bigport.

I have been told these are fine to run with the factory ECU. Opinions?

Thanks, Ben.

[AJPS]

Given you can make more than cams from an ECU (bullen made 79rwkw) with a computer, I would save up and get a computer and do it all at once.

To summarise. Buy an ecu.....

[Hen may possibly be a nut]

Ages ago a friend threw a set of 272deg cams into an otherwise stock bigport (I think he wrote about it on Toymods.. maybe user "cnic82" or "craigy" about 5 years ago). He said they made a noticable improvement and everything ran fine.

So yes, you can do it. Of course it's not optimal (as Dave says, tunable ECU will help make the most of them), but it should work.

Hen

[benzo]

Obviously an aftermarket ECU would be ideal, but this is only temporary. Surely the difference will be felt.

A tuned motor with ECU will be fitted at the end of the year.

[R&D Mechanical]

With the small cam size it will be alright for now but get a ecu to get the maximum out of them :)

[sundee]

What Hen said - 264' definatly, and 272's have been done before aswell i think

[Frak]

264 HKS's on stock ecu, sure a/f ratio is not perfect. This was after quite a bit of messing around with cam timing.

http://www.ae86drivingclub.com.au/dcimages/2/1/9/52002.jpg (http://img715.imageshack.us/i/aspowerc.jpg/)

http://www.ae86drivingclub.com.au/dcimages/2/1/9/52003.jpg (http://img189.imageshack.us/i/astorquec.jpg/)

[ke70dave]

whats with the massive jump of torques from about ~3200rpm?

TIVS opens up at about 4300 yer? (assuming its a bigport) not that that should make a jump in torques, but its about the only thing i can think of that happends around that RPM.

good to see some actual data though.

[Frak]

It's the load coming up on the dyno(even tho full throttle when run started, I can explain how this happens if you wish, but bit of writing) so ignore the first part of the curve.(also ignore the hair, it gives no extra power)

[Frak]

and not to nit pick dave but please don't call it torqueS, every time I hear Jeremy Clarckson say that, I cringe, it's just a pet hate :)

TVIS openeing will increase torque, when TVIS opens VE increases, more air, more fuel, bigger bang, more torque, more power.

[ke70dave]

haha, yer but its such a good word "torques"....and i may have watched every topgear episode...about 12 times each.

ah makes sense about the dyno, i can understand whast going on i think, my udnerstanding is that the dyno restricts the wheels turning to take measurements, so i assume the restriction isnt constant at the beginning of the run...or something like that.

hmm makes sense about TVIS too.

torques....

[Slimer86]

Ben, mine is running a set, just timed to HKS setting, and has picked up a noticeable improvement, especially in the top end.

[benzo]

With the small cam size it will be alright for now but get a ecu to get the maximum out of them :)

^



A tuned motor with ECU will be fitted at the end of the year.


What Hen said - 264' definatly, and 272's have been done before aswell i think

I picked up my set of 264's quite cheap.

Thanks Frak, that's some really really good results.

Time to chuck them in and get a tune then :)

[parakeet]

I have run 268's inlet /exhaust in mine for years with stock Jap ECU. When i bought them, Wade Cams said they did some development work with Toyota and that 270-272 was about the maximum duration the ECU could cope with. Of course, the fuelling and timing is not optimal however.