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Hi Everyone,

I have read through the various debates on the forum about 1.6 vs 1.8 engines with regards to power and most people say ditch the 1.6 and go straight for the 1.8. Some of the arguments are based around power and driveability etc.

BUT - In most cases there are not any real specs and figures to add to the debate. My car is a sprint car, so I really don't care if it is a pig to drive at low rpm etc. So in light of the cost of a second hand 1.8 engine, I think I can build a good 1.6 engine (might cost a little more, but will be new rather then a relatively unknown quantity).

Does anyone have a highly tuned 1.6 that they can quote specs and power figures from.

I am thinking of the following
Throttle Bodies, Cams, lightened, high compression. (For people thinking you need an ecu etc that adds to the cost - it is a good point but, I have an ecu, wideband, knock sensor, etc already).

Please try and resist opening up the whole 1.6 vs 1.8 debate again, because I am sure people won't thank me - just interested in real facts and figures for a high spec 1.6 motor.

Thanks
Si.

Mines not high spec, but went from 74kw with exhaust/extractors and intake to 81kw after installing Mahura cams and adjustable cam gears, thats with the standard ECU. An aftermarket ECU and removing the AFM should see more gains. The power was the same down low with gains up top, now pulls to the rev limiter where it use to drop off around 6.5k. The motors a 93 long nose 1.6 with about 85,000k's on it.
I'd love to see some figures from an ITB instal.

rossint wrote:Mines not high spec, but went from 74kw with exhaust/extractors and intake to 81kw after installing Mahura cams and adjustable cam gears, thats with the standard ECU. An aftermarket ECU and removing the AFM should see more gains. The power was the same down low with gains up top, now pulls to the rev limiter where it use to drop off around 6.5k. The motors a 93 long nose 1.6 with about 85,000k's on it.
I'd love to see some figures from an ITB instal.

Is that at the flywheel or wheels?

At the wheels.

the following might be useful as it contains a list by the OP with feedback from forumites:
viewtopic.php?f=29&t=32966&start=15

adamjp's na6 rebuild thread might also be of interest:
viewtopic.php?f=29&t=35703

these aren't the only ones around, but they spring to mind - I'm sure mx52nv has also provided some very useful advice in this area - well worth a search of some of his threads.

rossint wrote:At the wheels.

Wow - I think my engine might just be old and tired then - has done 200km.

My engine is stock but has - removed afm, headers, buddy club spec 2 zorst, megasquirt pnp. It only produced 93rbhp (68kw). No matter what we did with the timing it made no difference to the power. I guess there could be something else in the drive line taking the power, but probably the engine is just tired. I compression tested it and all cylinders were around 175psi, not the best, but not bad.
Si.

My timing was 14deg before the cams went in, and yes my engine feels pretty fresh. Another thing to factor in is that different dyno's will give you different results, it's possible the one I used reads higher than the one you use. Don't read too much into the actual power figures but look at percentage gains from each mod. The cams gave me about 8% gain and cost around $1000 fitted and tuned (bought off a forum member) I was more than happy with that. The cheapest mod you can do to gain power is try to shed weight, which is what I'm slowly trying to do at the moment.

time to massage my groin. * insert gloat emotiocon*



so....

genie extractors
2.25" exhaust
enlarged Mania CAI
Tighe 935 cams 276 duration, 8.9mm lift yadiya.....
adaptronic
removed AFM.
4,1:1 Diff

Idle & transient throttle at low rpm still; require work. but on song.....She recites poetry.

the engine itself came out of a 1.6 1991 JDM import.
It had 30k km
this car was then converted to a racecar. The race car did 10k km racing km in production sports & super sprints over a period of about 3-4 years.
This engine was the put into Patchy in 2004. I've done just over 50k km since. Nothing has been touched apart from the valve guides have been ground back.....so the cams clears the the head while rotating. The head may have been removed for that. Not sure.
so..... your engine being tired at 200k ......It's possible but I'm not convinced. But I guess if the previous owners never changed oil & so on.....

Is that 106BHP or KW?

Nice, any figures with a standard ECU, your cars pretty similar to mine except for the ECU.

unfortunately I don't have figures between stages. I did drive it in different stages when all the bits were being installed over a period of about 4 weeks. But unfortunately no Dyno figures.

However the same engine on the same Dyno
ECU with crystal modification. 7500 max rpm
AFM tuned to accommodate crystal
Mania CAI without the enlarged intake
standard exhaust
16 deg BTDC

was 72 RW kw

rossint wrote:Nice, any figures with a standard ECU, your cars pretty similar to mine except for the ECU.

are you sure your cams are similar? those are some pretty aggressive cams

No, my cams are not that aggressive which is why I used the word similar
IN : 248degree 8.5mm lift
EX: 256degree 8.5mm lift

106rwkW is very impressive for a 1.6L. For further reference PeterB's Fanta makes 93rwkW at 8000rpm.