Xu7 16v

[KRISKARRERA 2 1 Cars]

I suppose yes, but does the weight of the car make any difference? A clutch would have a harder life in a 405 thaN A 205 mI16 for example.

[Grim.Badger 15]

Liners possibly, sump pan (nicer alloy trap door design), oil pump. Rods are the same dimensions as 1.6 8v, crank could be used to stroke a 1.6.

Oh and the flywheel is a usefully lighter alternative to the Mi16 one, with a 200mm clutch and timing teeth.

 

I don't understand what you mean by stroke a 1.6 Does that mean it is the same as a 1.6 or will increase the capacity slightly? Would having a counter balanced crank provide any benefits in anything but a track car?

Given what you say about the liners being exchangable I presume that means the bore is the same; could you bolt a 8v head onto one of these bottom ends without having a ludicrous CR?

[welshpug 1,622]

wouldnt bother with an 8v if the 6 head hits!

[Grim.Badger 15]

wouldnt bother with an 8v if the 6 head hits!

 

Yes but:

 

1: I want to try and re-use my 8v management to cut costs as I'm poor and to reuse the 8v management I would need to retain the 8v inlet AFM and TB.

 

2: 16v is more power than I want at the moment, I've no real need for much more power than the 1.9 8v has.

 

3: I have an 8v head in good condition and can't be bothered paying for a 6 head in good condition or reconditioned.

[welshpug 1,622]

fairy muff, cant see why not, as it was an 8v when it was used in the 405 and earlier 306's (I think the 306 got the 8v version)

[pug_ham 240 3 Cars]

If you fit the crank from an XU7 into a XU5 you will have an XU7 1761cc 8v. These were fitted in the ZX, 306 & 405's but develped low power figures (100bhp & 115lbft).

 

Making the XU5 into an XU7 though would probably unleash a few extra horses due to the different head & cam used on the engine. Haynes doesn't list the valve sizes for the XU7 though.

 

Not sure how well the standard ecu would cope though.

 

Graham.

[Anthony 1,000]

Not sure how well the standard ecu would cope though.

Should be fine - Jetronic seems to cope exceedingly well thanks to its simplicity, and considering I've had 1.9 8v's run perfectly happily on 1.6 management/injectors I can't see either 1.6 or 1.9 management having an issue with a 1.8. The ignition advance curve might not be ideal, but so long as you don't stray much over 10:1 compression it should be close enough.

 

Generally speaking, management with an AFM adapts to change quite well, whereas managment using MAP sensors normally need remapping for anything other than minor modifications.

[Grim.Badger 15]

I'm thinking of using it for the fancy la-de-dah bottom end (crank, rods and pistons) to make a cheap high spec 8v. I was hoping that with a GTi head and cam it should get close to the 1.9 in power, unless the CR ends up very low. I was also hoping it would make a revier engine than the 1.9 without losing too much torque; this is something that would attract me. I'm not too bothered about losing a couple of horses within reason.

 

It's a bit of a pipe dream but its looking like there may be a problem with my new engine so I thought I would look into it.

 

I thought the jetronic would be fine as the ECU only takes signals from the AFM flap, AFM temp sensor and coolant sensor iirc to control the fueling none of which will be that effected by a bottom end change. The main problem would be if the AFM cannot be adjusted enough to provide the correct fueling but with the same head being used I can't see there being a problem.

 

EDIT: Are you sure the 8v version has the same crank/rods/pistons?

Edited May 1, 2007 by Grim.Badger

[McPikie 0]

So, basically, as a cheap 200cc upgrade, you can just what the 1.8 16v crank onto the bottom of the 1.6 8v rods and bish bash bosh??

 

Wouldnt you then be better off running 1900 INJ/AFM/ECU? Or would the 1600 stuff suffice?

 

Just thinking of a cheapo upgrade, or would it be just a easy to swap the full lump over?