Just had the results of the winters engine work confirmed on the Austec rolling road.

I have a 1600 4AGE 20v ST engine which was rolling roaded last year with 154.7BHP which is good for a 4AGE 20v.

Since this time I've had the following done to the engine:

* Head ported and flowed by Hellier Performance
* 264 Fast Road Cams from BPJ Services
* Velocity/Ram Tubes from Jenvey via BJP
* Fidenza lightweight flywheel.

Was hoping to get 170-175BHP - Would have been really happy with that.

Here is the new plot:


Dyno 2

191.8bhp and 131.5lbf.ft torque. Result

BTW - It sounds great and is a monster to drive!

[Edited on 1-6-2009 by Worzey]

RESULT! great stuff - makes me very hopefull for my blacktop when I start that phase of the process of tinker and modify. Did you use the same valve springs?, vernier cams? dare I ask how much??.....

NICE !!!

I got uprated Supertech valve springs but didn't go with new Vernier cams.

It wasn't cheap.

With all the other bits i.e. NGK plugs, TRD Head gasket, Rolling road etc it cost around £2k

Did you forget to take the handbrake off?

Its the 135bhp at the wheels that counts...

Agreed - but are they acceptable losses?

I thought all quoted BHP was measured at the flywheel but agreed it's the wheels where it matters.

What can be done to minimise losses?

Brilliant - Fantastic result...Well, done...

Always nice to come away with more than expected :-), I had a similar experience with my recent RR session :-)

wow

quote:

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Originally posted by Worzey

What can be done to minimise losses?

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Awesome! 120bhp/litre is going some. There is something magic about breaking the 100bhp/litre barrier.

Those rolling loses do seem quite high though - my car had 135bhp at the wheels and thats only with 175bhp.

Depending on the size/number of rollers i think tyre pressure may have quite a big effect.

Edit:
Also did they do a run down test? - I've heard of some rolling roads just refering to a database for the frictional loses - so that may have skewed your results

[Edited on 1/6/09 by Project7]

I'm running a standard Type 9 gearbox with a 3.92 diff.

Tyres are usually fairly soft 18-20psi (R888's).

I assume a gearbox rebuild with a Quaife Diff might help a little.......where did I put the cheque book?

I was thinking of the Rotrex Supercharger kit next winter which should give close to 280bhp so I'll need the Type 9 and drivetrain rebuilding anyway.

quote:

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Originally posted by Worzey
Agreed - but are they acceptable losses?

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quote:

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Originally posted by Worzey
I was thinking of the Rotrex Supercharger kit next winter which should give close to 280bhp so I'll need the Type 9 and drivetrain rebuilding anyway.

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Hmmm......I'll have to check what gear the power run was completed in.

The tyres aren't too flat

I've chewed up 2 rear wheel bearings in the past 1000k (one each side).

I wonder if the diff might be the problem?

Could also be binding brakes, or suspension geometry problems.

very nice graph, must be a real hoot to drive with all those revs to play with. What car is your engine from?

I must say those drive train losses seem a little high, thats 30%, rx7's typically lose 18% which always seems accurate when compared with the rollers flywheel calculation.

quote:

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Originally posted by Project7
Awesome! 120bhp/litre is going some. There is something magic about breaking the 100bhp/litre barrier.

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Hi,
Nice result from just 1600cc. I have often considered using this engine instead of my Rover V8. Maybe some day...

Just one observation which surprised me from your power graph. Your torque curve seems to keep climbing right up to the peak power RPM so peak torque and peak power are both at more or less max RPM. I've never seen this before. It may just be because it is a high revving engine but it seems to suggest to me that the engine hasn't actually reached its peak power or torque yet and the RPM is being restricted by something else (eg. rev limiter or valve bounce). Maybe the engine is simply not capable of more revs, I don't know about the 4AGE.

Any graphs I have seen usually show peak torque at maybe 2/3 rds of peak power RPM (5200 for standard 4A-GE) and the power graph starts to flatten out before it peaks and then starts to drop in power as revs increase beyond the peak. Your power graph seems to increase in gradient at 5k (VVT I guess) and never seems to flatten out at all until the rev limit. Is this to be expected with this type of engine in this state of tune? I'm used to lower revving V8's and such...

Cheers,
Craig.

ps. You can work out which gear the test was done in by looking at the speed reading versus RPM on your chart. 130.5 MPH at 7680RPM

[Edited on 1/6/2009 by craig1410]

[Edited on 1/6/2009 by craig1410]

So I guess that means it was done in 5th gear. That could explain the losses

I think they sometimes run cars in 5th to get better traction. When I had it done last time I have a vague memory they had some issues getting traction as it was bouncing on the rollers.

The curve is interesting. The on road experience backs this up. When the VVTi kicks in it pulls like a train right to the rev limiter.

The rev limited is set around 7,800rpm if I recall correctly. In fact, I've had the shift-light set at 5k (from 6.5k) as it revs so damn quickly I needed time to change before it hit the rev limiter.

I'm not sure exactly where the engine came from - Toyota Levin 20v maybe?

all sounds good! my zetec 1.6 made 152 at the wheels, and 174 at the fly, and like yours revs to 8k, not that ive been that high yet,

Hi,

I do have a fair amount of experience with these engines and I can say with confidence they will comfortably rev to 8500RPM and not be over stressed. The blacktop version in particular, which had lighter internals and a lighter flywheel, was supplied with rev limiters over 8000RPM from the factory. In typical Japanese logic most of these engines were sold in automatic town cars which invariable got little servicing and come over here coked in carbon and thick oily deposits.

They are also quite frustrating in that they are well developed factory engines with a fairly uncommon 20V design. Unfortunately due to the small capacity and 20V valve train they are also limited in scope for developement. The very small cam follower buckets and having 3 inlet valves crammed in an 81mm bore does ultimately limit the breathing. That's why I very quickly decided to go forced induction on mine.