ross009 0 Posted September 20, 2007 Before i start i just want to say im not trying to break any records with what im intending to do i just want a lively 1.9 8v i can use for some track days and some b raod thrashing. im basicall gonna rebuild a 1.9 8v to go into my 1.6 which is slowly dying so heres what im planning on getting done in time for next summer. rebuilt 1.9 bottom end with lightened and balanced flywheel 1.6 gearbox 1.9 head with 3 angle valve seats skimmed to around 10:6 cr catcams 279 cam with vernier pulley twin 40's or r1 carbs not decided yet (opinions welcomed) prob some ignition only management 4 branch exhaust manifold looking for around 145-150 at the flywheel do you thin this is obtainable at this spec? is there anything in there that strikes people as being a waste of money? the 3 angle valve seats maybe? i cant really afford a lot of head work at the minute and dont want to go down the mi route before anyone says it just want a good strong reliable(ish) 8v so just looking for some feedback on what i have planned tks Share this post Link to post Share on other sites
max0 5 Posted September 20, 2007 (edited) hey Think the 1.6 fly is 1kg lighter as standard than the 1.9, The Xu10 heads have a better flow rate and fit on the 1.9 block - a cheap and easy upgrade which is quite common - could even spend money on having it skimmed etc There just a few things you may want to look into to save a few quid. rest looks good Andy Edited September 20, 2007 by max0 Share this post Link to post Share on other sites
boldy205 75 Posted September 20, 2007 sounds good!! as above though, the XU10 heads are supposed to be better flowing than yours. Plus from what i know you wont gain much from porting your standard head unless you go for big valves, so stick with the XU10 head. Share this post Link to post Share on other sites
ross009 0 Posted September 20, 2007 Firstly apologies for the multi posting of this topic ive closed one in xu performance and modified section which can be deleted and the other one in this misc/general tuning section can be deleted also having some real comp issues! anyways thanks for the feedback guys i have looked at the xu10 head option but after reading a very long topic on it on here i was put off slightly due to the restrictive exhaust ports? but if people believe its still a benefit even eithout having additional work carried out to the head then that probably is the route i will go down. tks again Share this post Link to post Share on other sites
ross009 0 Posted September 21, 2007 also whilst on this with a cr of 10:6:1 am i likely to get detonation lower in the revs around 3k like some people do when running the higher cr's? if so will i be able to retard the ignition slightly on the dizzy without affecting top end power to much as new management is last on the shopping list really or do i need different management? cheers Share this post Link to post Share on other sites
Craigb 2 Posted September 21, 2007 I would expect you to pass the 150 mark with that spec. I have 150 from a similar spec without the 40's although mine has larger valves. If you want the best from it though , go for the mapped ignition and possible upgrade to fuel when costs are less of an issue. Share this post Link to post Share on other sites
wardy18 33 1 Cars Posted September 21, 2007 quick question to make the XU10 head clear in my mind when you get a Big Valve XU9 head arnt the valves the same size as an XU10 head?! ive been told they are, ie 1mm over size are fitted when Big Valving an XU9 and the XU10 valves are 1mm bigger than XU9 anyway a big valve XU9 head can cost up to an around £800 but surely if the above is correct wouldnt it be alot cheaper to just get a XU10 head (£100) and get it ported and polished for a total of a lot less than £800 and the same outcomes?!? please set me straight if i have got this wrong but from what i have been told and read so far this seems more logical?! many thanx simon Share this post Link to post Share on other sites
ross009 0 Posted September 21, 2007 kind of right yes i believe an xu9 big valve head has 1 mm bigger valves but im guessin the 800 pound price you've got is possibly from pumas site? which for 800 pounds from there it includes all the porting and polishing work ect which from what i can gather is top notch never heard a bad thing about his work! but still the xu10 head does have some draw backs like a more restrictive exhaust side if you do search there was a very in depth discussion about this and the conclusion seemed to be if your on a budget then and xu10 head with some light work done to it is ok but if your willing to spend the money go for a bv xu9 head thats the way i read it anyway. hope that helps Share this post Link to post Share on other sites
wardy18 33 1 Cars Posted September 21, 2007 kind of right yes i believe an xu9 big valve head has 1 mm bigger valves but im guessin the 800 pound price you've got is possibly from pumas site? which for 800 pounds from there it includes all the porting and polishing work ect which from what i can gather is top notch never heard a bad thing about his work! but still the xu10 head does have some draw backs like a more restrictive exhaust side if you do search there was a very in depth discussion about this and the conclusion seemed to be if your on a budget then and xu10 head with some light work done to it is ok but if your willing to spend the money go for a bv xu9 head thats the way i read it anyway. hope that helps yeh thats great, thanks for the info Share this post Link to post Share on other sites