blackpug 0 Posted August 16, 2007 Hi, I'm rebuilding my 1.9 lump at the moment for road rallying and i've been given 2 different lots of advice about what to do. Some people say to put 1.6 pistons in while another person (a renowned pug expert) has recomended me to just take a heavy skim off the head and keep the 1.9 pistons. I am also unsure of what cam to go for, ideally i want a catcam as i've read many good reviews on here but most of these are in engines on carbs whereas i must keep the standard injection system due to the rules and regs. Any recomendations? One last question ( ) 1.6 and 1.9 heads are the same arent they? Cheers, Adma. Share this post Link to post Share on other sites
welshpug 1,657 Posted August 16, 2007 IMO its best to use different pistons rather than skim the head, as if the head ever needs replacing you can just bolt on any good condition unit without needing to send it off for another skim. As for keeping the Standard injection does that mean the intake or the system as a whole? I.E could you run a system like emerald or even Motronic on the original 8v intake manifold? Share this post Link to post Share on other sites
Craigb 2 Posted August 16, 2007 I had a big skim on mine , but if i was doing it again i would go down the route of the 1600 pistons. Cat cam works well with in mine , after a year of running with it i am just about getting the hang of driving mine now . Share this post Link to post Share on other sites
blackpug 0 Posted August 16, 2007 TBH i'd never thought of the head swapping issue, but will 1.6 pistons raise the cr too much to run on the standard management? (i think it's fine to use aftermarket management - the inlet plenum must remain stock - but the cost is too great at the moment anyway). So if i'm running standard injection and 1.6 pistons can anyone recomend a catcam suitable (i'm lost when it comes to the facts and figures!)? Share this post Link to post Share on other sites
Craigb 2 Posted August 16, 2007 the spec you are talking about is basically the same as the 205 1.9 scholarship cars (still on std inlet manifold) . the only issue you will come across is if you chose too wild a cam . I believe that mine is towards the too wild for the std inlet , as it was still wanting to make more power at the rev limit on Mikeanics rollers Share this post Link to post Share on other sites
welshpug 1,657 Posted August 16, 2007 (edited) I would see if you can find a Motronic setup off a ZX or a 405 SRi, IIRC Pugtorque has an uprated cam in his engine which this system copes well with. you'll have to change the flywheel and thermostat housing, and possibly the throttle body, but its definitely woth it as theres no AFM to die halfway through a stage... I remember seeing the spec of a 205, which I think had been colin Mcrae's car once, it was totally standard blueprinted, but with emerald fitted, and I'm sure the quoted power output was circa 145 bhp. Edited August 16, 2007 by welshpug Share this post Link to post Share on other sites
blackpug 0 Posted August 16, 2007 Which cam do you have Craigb? Ideally i'd be looking towards the equivalent of the PTS group A cams, although i know to really use one of these means the rev limiter should be removed. Share this post Link to post Share on other sites
Craigb 2 Posted August 16, 2007 Mine is Cat Cam 4900340 I would like to try a 4900342 at some point a little bit milder ! ( but not Much) Share this post Link to post Share on other sites
Rob Thomson 6 Posted August 16, 2007 Just to clarify the rules... you have to run the standard plenum and throttle body but otherwise you can do what you like to the injection system. Ditching the AFM has to be a good plan. Personally I'd leave it standard unless you're a driving God and have an awesome navigator lined up. Share this post Link to post Share on other sites
blackpug 0 Posted August 16, 2007 I was thinking of the 4900340 after reading the pumaracing tech stuff, to use that one you need the uprated valve gear right? Share this post Link to post Share on other sites
Craigb 2 Posted August 16, 2007 (edited) I was thinking of the 4900340 after reading the pumaracing tech stuff, to use that one you need the uprated valve gear right? for reliability yes! But from experience , i think it is too much for the STD plenum. Smckeown had this same head and cam , but with bodies and the torque and power profiles were massively different . I think it was blackscooby who had the 4900342 on his and commented on the difference in power delivery Edited August 16, 2007 by Craigb Share this post Link to post Share on other sites
DamirGTI 342 Posted August 17, 2007 (edited) Hi ! I've done this on my engine but with the pistons from DFZ engine (1.9 CTi) they are the same shape and piston crown type as the ones from the 1.6 engines but the trick is that you don't have to change the conrods on this flat top DFZ pistons because they are the same length as the ones on standard dished 1.9 D6B engine pistons So you have less trouble with this DFZ pistons for this rising CR upgrade , if you chose 1.6 pistons you will have to press out the 1.6 conrods and press in 1.9 conrods in these 1.6 pistons and this is a bit hard job if you don't have the special tools for that job , also one of the pistons can break/deform during this pressing in pressing out of the conrods .. much easier is to find a set of DFZ pistons ! as i sad you don't need to do anything to them just clean them fit the piston rings and fit inside the engine ! Anyhow me thinks that this is much better solution then heavy head skim , CR with this DFZ pistons will be around 11.1 (or maybe 12.3 I'm not sure ) but my engine now has great torque all over the rev range and pulling much stronger then before when was standard (all thou I've done the head job also and some other things ...) If you need any more info regarding this please ask ! Cheers ! Damir Edited August 17, 2007 by DamirGTI Share this post Link to post Share on other sites
blackpug 0 Posted August 17, 2007 So, what's a DFZ engine? I was thinking of 1.6 pistons as i need to strip my spare 1.6 lump to use the head as the exh valve seats in my original head are fubar'd. Pressing the gudgeon pins out arent really a problem, but if these DFZ pistons are easy to get hold of (and not too expensive!) then i may go for that. Share this post Link to post Share on other sites
DamirGTI 342 Posted August 17, 2007 (edited) Hi ! See this : http://forum.205gtidrivers.com/index.php?s...1698&hl=DFZ As sad this pistons are the same crown shape as the ones in the 1.6 engines , and you can source these 1.9 flat top pistons from these engines : XU9J1 DFZ (102 Hp) : from the 205 CTi (cabrio..) , and also in 309 - 405 1.9l 8v (from 98 to 105 Hp) pugs .. But , me thinks that 309 - 405 1.9l 8v XU9M DDZ pug engines also haves these flat top pistons .. I'm not sure about that but someone from here will know if this is correct ... However lots of this 205 CTi - 309 - 405 1.9l 8v "low" Hp engines are dumped on scrappy I'm sure that you can find/buy set of these pistons very cheap or maybe complete 1.9l CTi engine as because nobody wish them in 205 - 309 GTi cars .. Cheers ! Damir Edited August 17, 2007 by DamirGTI Share this post Link to post Share on other sites
