Tu Tuning, I Just Want 100Hp

[welshpug 1,621]

Different engines

[309jazzpanda 39]

I know the series 1 rallye was a smaller engine with mad cam and that but what about the series 2? Wasn't that a 1600

[MiniGibbo 142]

S1 106 was a 100hp 1300. S2 106 was a 103hp 1600 and a bit pants in comparison.

 

The s1 uses a metal inlet and iirc a better cam.

[309jazzpanda 39]

Yeah the series 1 was a very different engine but what made the series 2 engine 103 bhp when the saxo was 90bhp

[calvinhorse 870]

Are you sure the series 2 was 103bhp?

I thought they had the blacktop tu5 engine 90bhp? 103bhp would make it the same as the 1.6 106 xsi.

[MiniGibbo 142]

s2 rallye is 100% 103hp.

 

And heres the specs

 

http://www.106rallyeforum.com/forum2008/index.php?pageid=specs

Edited December 13, 2012 by MiniGibbo

[309jazzpanda 39]

But what's the difference then, bigger cam than a saxo? Management?. Also lets have a vote for my gtx,Series 1 or 2 engine. Its not having a 16v as it will mean I'll have to make the 309 faster

[MiniGibbo 142]

S1 is alloy where the s2 iirc is cast iron so heavier.

 

I don't know the answer as to why it has more power but I'd guess a mix of cam profile and mapping

[309jazzpanda 39]

That's what's swinging me to series 1 Engine my spi is a heavy iron block

[N3VRAM 12 1 Cars]

But what's the difference then, bigger cam than a saxo? Management?. Also lets have a vote for my gtx,Series 1 or 2 engine. Its not having a 16v as it will mean I'll have to make the 309 faster

S1 all the way! The rallye S2s are a bit of a disappointment compared to the S1s at my car club. I suppose the challenge is to find one with low mileage that hasn't been ragged - which must be bloody hard as why else would you buy a car like that in the first place?

Edited December 17, 2012 by N3VRAM

[309jazzpanda 39]

Yeah it'll have a rebuild before it gets put in but I think it'll be worth it

[309jazzpanda 39]

http://www.ebay.co.uk/itm/Peugeot-106-Rallye-Piston-And-Rods-Saxo-Race-/321088482307?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item4ac25d6c03

 

Are these pistons the same as the 106xsi? 1400 tu I mean?

Basically could these go in an alloy xs block

Edited March 13, 2013 by 309jazzpanda

[Vili 17]

http://www.ebay.co.uk/itm/Peugeot-106-Rallye-Piston-And-Rods-Saxo-Race-/321088482307?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item4ac25d6c03

 

Are these pistons the same as the 106xsi? 1400 tu I mean?

Basically could these go in an alloy xs block

 

I´m very much interested in this as well. I bought 1360 xsi engine last weekend and realized only at pickup that it had iron block. Now I'm trying to find alloy block to build lighter engine. BTW those pistons look crap. They look that they'll weight a ton and you could have 10 mm longer conrods with shorter and lighter pistons. Is there any better cheap alternatives for xsi pistons?

I actually bought twin 40 Solex's as well. Return into the dark ages it is... ​

[Vili 17]

Would it be possible to put 1.4 xsi pistons on 1.6 TU conrods and machine down the piston crown? I read somewhere that 1.6 rods are 6,7 mm longer than 1.4.

Of course none of this makes any sense if you have to pay for the machining involved.

[309jazzpanda 39]

Why would you want to put them on 1.6 rods?, I know the xsi pistons will fit in an alloy block but will thetu2 pistons fit into it

[Vili 17]

Because that way I could make the pistons lighter and get marginally better rod stroke ratio.

 

edit: I haven't opened my 1.4 xsi engine yet so I can't say if the pistons are same as those rallye pistons.

Edited March 16, 2013 by Vili

[Vili 17]

I weighted my xsi engine. I knew it's heavier than alloy block but 110 kg!

Didn't the time to take the head of to take a peek at the pistons, but maybe tomorrow.

[309jazzpanda 39]

They should be the same, they're domed on the xsi if they are don't get them machined they are super rare and I need some so I can have a1600 head.

[Vili 17]

I took the pistons out. They look exactly like the pistons in the eBay.

There is "only" 7,something millimeters of material in the piston crown. So they can't be machined down more than 2-3 mm. I'll just use them as they are with their own conrods.

I still think the pistons are just stupid with their huge compression height and weight. But since I'm building a budget engine they'll have to do.

[kee 20]

have a look at ford crossflow pistons and then come back here

for reference, those xflow pistons can rev to 10k rpm in a tuned 1300

[Vili 17]

Done it and now I'm back, ugh. I'm sure they can rev to 10k, but they'll need very strong(heavy or expensive) conrods and crank. Crossflow pistons design is probably based on challenging combustion chamber design which will need huge dome. (I know nothing about Ford engines.) But there no such reason for TU-pistons. Peugeot probably chose that less than ideal pistons design because they didn't want to make new conrods for the xsi engine.

Now days every car company uses very low pistons with the smallest possible skirt because weight and consumption are among the most important design principles. I won't say xsi pistons don't work. I'm saying they could be better and if there was better inexpensive option for them I would choose the option.

[kee 20]

kent crossflow heads are flat, no combustion chamber, so the combustion chamber is in the piston crown and remaining bore only.

 

The reason for the xsi domed pistons?

Possibly helps with squish within the combustion area?

[Vili 17]

kent crossflow heads are flat, no combustion chamber, so the combustion chamber is in the piston crown and remaining bore only.

 

The reason for the xsi domed pistons?

Possibly helps with squish within the combustion area?

 

My bad. I put ford crossflow piston to google picture and the weird looking pistons with huge protruding dome which I thought were Ford are actually for Evinrude crossflow outboard motor.

There's nothing wrong with the small dome on the xsi pistons, but the overall height of the pistons which makes them unnecessarily heavy. But I guess that's how they made them in the 80's.

[309jazzpanda 39]

106 xsi came out in the 90's, you've got to remember this is a quick little road car not a full on group a rally car. Its built to be driven everyday by normal people so needs to be durable, as well as cost effective for the manufacturer.

 

Anywho, back to the original thread. Well I've won the rallye pistons on eBay but also purchased a vtr engine as well ha ha.

Dropped the oil in mine on Sunday and quite a lot of swarf came out, doh! So engine purchased going in next week, hoping I can over time build a quick 1400 engine in the shed

[kee 20]

if you don't want those pistons i'll have them, it's nearby too so I can go collect