A Little Problem I Need Some Help With!

[Arahan 4]

Basically the car i've just bought has a 1.9 bottom end but has a 1.6 head (and cam), and is using 1.6 injectors and ECU.

 

Now, the car goes really really well (maybe a little lumpy low down) but i was wondering if it would be better to swap to a 1.9 head or at least cam, 1.9 injectors and 1.9 ecu? As the car is basically a stroked 1.6 isnt it?

 

Just need to know before i go ahead and do it and possibly lose some performance as it really does run very well!

 

Thanks! - James

[Anthony 1,003]

If it runs well then leave it. The 1.6 management has plenty of headroom for fuelling a standard 1.9 and the AFM will compensate for the extra air.

 

Later 1.6 heads and 1.9 heads are the same anyway, so no point in changing that.

[Arahan 4]

I thought the cam was different though? The only problems are that it is lumpy low down, from idle at about 900 to about 2000/2500 or so, after that its nice and smooth, pain in the bum driving around town and doing manouvers though! (spelling!) Could just need a tune up and the fuel air ration adjusting??

 

EDIT: For spelling! Again!

Edited August 29, 2007 by Arahan

[28CRAIG 2]

I always thought that the 1.6 cam was a upgrade to the 1.9.

 

Proberly worth making sure that the car is set up properly.

[Arahan 4]

it does feel rather quick! Very torquey!

[boldy205 75]

Like it has been said, how old is you engine? As after acertain year (1989 i think?) the heads and cam were the same. I have a 1.9 Non CAT ECU and injectors if you want them?

[Arahan 4]

I was thinking of swapping the lot, AFM, ECU and injectors, but I may just swap the Injectors for some 1.9 ones and see how that affects things. I mean what would be the point of Peugeot changing the AFM, ECU and Injectors if it wasn't necessary?

[boldy205 75]

As far as i know the AFM injectors and ECU are differant, but as said they still 'work' with a 1.9.

I put a 1.6 AFM on my 1.9 (as a test to find out a problem) and it ran exactly the same.

[Arahan 4]

I could just be disillusioning myself over the different parts as to the cause of my lumpy idle, it may simply need adjusting. Think I should book myself in for a tune up! Maybe a rolling road sesh while im at it!

[Richie-Van-GTi 71 2 Cars]

Id stick it on the rollers and have a look how well its delivering the power to give an idea if the advance curvbe suits the current set up and also to see how well its fueling through the rev range. Then you can make an informed decision.

[steve@cornwall 100]

Id stick it on the rollers and have a look how well its delivering the power to give an idea if the advance curvbe suits the current set up and also to see how well its fueling through the rev range. Then you can make an informed decision.

 

IIRC, the 1.9 ecu opens the injectors longer than the 1.6 and slightly overfuels it. I found mine better after swapping to the 1.9 items

[Arahan 4]

Ah thats good to hear, so 1.9 ECU and injectors sound good

[Anthony 1,003]

There really is no need to swap the 1.6 injectors/ECU/AFM over to 1.9 kit in my experience - certainly I've done a few 1.6 - 1.9 engine upgrades and retained the existing management, and they've all run very well indeed with a good idle, good economy, and pulling strongly throughout the rev range (and as a bonus you get a slightly higher rev limit)

 

Remember, before the 1.9 GTi's were officially released by Peugeot, the 1.9 engine conversions from SBC and the like all ran using the 1.6 management.

 

IIRC, the 1.9 ecu opens the injectors longer than the 1.6 and slightly overfuels it. I found mine better after swapping to the 1.9 items

It'll be the other way around - 1.9 ECU is designed for higher-flowing injectors, so will open them for a shorter period for a given fuelling requirement.

 

This is why mixing 1.6 and 1.9 injectors/ECUs/AFMs isn't a good idea as the fuelling goes out of the window - run either full 1.6 or full 1.9 setup, not a mixture of both.

[Grim.Badger 15]

I always thought that the 1.6 cam was a upgrade to the 1.9.

 

It the other way around, the 1.9 cam is wilder and also less liable to wear.

As Anthony said you are best sticking to a full set (Injectors, coil, afm, dizzy, ecu) from either the 1.6 and 1.9 as they are designed to work together; it would be a good idea to get your fueling checked though and the afm adjusted if need be.

[steve@cornwall 100]

Another DOH! moment, Anthony, that's actually the way round I meant to write it - still think my upper revs suffered with the 1.6 stuff on the 1.9, though, quite flat at the top end compared to the 1.9 stuff.

[Arahan 4]

Thanks for all the replies!

 

I wasn't going to mix systems, thats why I wanted to know which would be better, 1.6 or 1.9 systems!

 

The other thing is that higher up the rev range, 55 maybe to 6 it seems to run out of puff, I thought that might be the injectors too, the 1.6 items running out of flow?

[Arahan 4]

Quick thought, adding 1.9 injectors to a 1.6 system wont have any adverse effects will it, as they are simply higher flowing injectors arent they? If its still 1.6 ecu and everything else, just having higher flow injectors wont affect things will it?

[pug_ham 244 3 Cars]

Quick thought, adding 1.9 injectors to a 1.6 system wont have any adverse effects will it, as they are simply higher flowing injectors arent they? If its still 1.6 ecu and everything else, just having higher flow injectors wont affect things will it?

It'll make the car over fuel, a few people have tried it before on here & reported that their engine oil soon smelt strongly of fuel & swapped back to the original stuff but this was when mixing a 1.6 ecu with everything else 1.9 but as its the ecu that controls the fuelling & the 1.6 ecu opens the injectors for longer I think it'll still overfuel.

 

Graham.

[Arahan 4]

Ah right that makes sense, cheers for that! - james

[Anthony 1,003]

The other thing is that higher up the rev range, 55 maybe to 6 it seems to run out of puff, I thought that might be the injectors too, the 1.6 items running out of flow?

Sounds like an average 15 year old 1.9 GTi engine to me - in my experience, these days only "good" 1.9 engines will happily rev right round to the limiter, and on most power is starting to tail off at 5.5k and past 6k there's little point revving it much more.

[Arahan 4]

It the other way around, the 1.9 cam is wilder and also less liable to wear.

As Anthony said you are best sticking to a full set (Injectors, coil, afm, dizzy, ecu) from either the 1.6 and 1.9 as they are designed to work together; it would be a good idea to get your fueling checked though and the afm adjusted if need be.

 

Would fitting a 1.9 cam be an 'upgrade' so to say then, over my 1.6 cam? And if i did that would it be best to switch to 1.9 injection system or leave the 1.6 as it has been pointed out that it can cope?