Corty1979 0 Posted May 3, 2015 I'm about to start building a tf cortina to run In modified production and I'm after some info on what's involved in getting a 250 xflow to run on methanol any help would be good just so I've got some idea when I visit the engine builders Cheers Share this post Link to post Share on other sites
matt_lamb_160 252 Posted May 3, 2015 Ando is your man then!! Share this post Link to post Share on other sites
ando76 4,354 Posted May 3, 2015 Thanks Matt. I'm actually fitting me prototype crossflow into Cortina race sump this week. It has been a long road on that one as I wanted to be able to run my stud girdle without modification and the modified production corty its going into has an awesome set of hand made extractors that run very very close to the sump. The extractors were built by a drag pipe expert and they run them close to the sump to help heat the oil in drag racing applications. Not really what you want in a speedway application tho so heaps of brain power went into that bloody prototype. Corty's suffer from oil volume but I have found a way around that now. Share this post Link to post Share on other sites
Corty1979 0 Posted May 3, 2015 So what is the best way of bringing up the Cr to run methanol are flat tops the way to go or dished Pistons Allso anything else would be help full Share this post Link to post Share on other sites
ando76 4,354 Posted May 4, 2015 Getting compression out of a crossflow is very very easy - even with dished pistons. I have a recipe I use for my speedway engines and I have shared it on many occasions. Do I make any money out of sharing it - no. If you have the skills you can reproduce the recipe. I suggest you have a look through the crossflow threads and my 'Ando's ute' members build thread. If you don't have the skills I'm happy to build one for you. If you go the self built route just make sure your sump and oil pump is up to the job. p.s methanol works without big comp. look at meth rotaries as an example. Share this post Link to post Share on other sites
Corty1979 0 Posted May 4, 2015 thanks ando ill check out those other threads im going to do as much of the work myself except for block and head machining ive ported my own manifolds before when i use to race holdens just wasnt really sure if getting power out of a xflow would be same as getting out of a 202 or 186 allso would the sump design be same as what you would do with a old holden 6 and i will be using a main cap girdle Share this post Link to post Share on other sites
wagoon 2,429 Posted May 4, 2015 oil pump is up to the job. So this must mean the use of a high flow oil pump then BHAHAHAHAHAHAHAHAHAHAHA 4 jca25, Ando81, ando76 and 1 other reacted to this Share this post Link to post Share on other sites
ando76 4,354 Posted May 4, 2015 sump design will be similar - although I don't know what you have done in the past. As stated the problem with the corty is oil volume. You can run a main cap mounted girdle - BUT it will end up very close around the k frame/ rack. I have a prototype corty sump which will run one of my girdles and I can tell you it is a very close fit - as with most things corty Share this post Link to post Share on other sites
Corty1979 0 Posted May 5, 2015 the sump i built for the holden was just windage tray plus some baffeling with pick up for oil pump through side of sump ive read through your some of your threads i see you know your stuff when it comes to these engines i was allways lead to believe you need close to 15.1 cr to run methanol guess i was wrong so after what ive read so far im thinking if i zero deck the block use flat tops an take say 20 to 30 thou of the head i should be around the 13 to 14 cr mark ? im doing to use hbeam rods as i want it to last a long time pistons im un sure on except ill most likely go 30 tho not sure how to go about the crank but have seen pics of your one in the ute build looks like it would be good for speedway to i use to do half arse knife edge jobs on the holden cranks i ran ill most likely get the head ported at the machine shop and have bigger valves installed just not sure on which size to use and inlet manifold ill cut and poert that out myself and ill be getting a metho 350 holley from clarkos peformance apparently he builds good ones oil pump ill just get an aftermarket high volume one Share this post Link to post Share on other sites
Ando81 2,950 Posted May 5, 2015 Ha ha don't mention high volume oil pumps to Ando76 1 winton reacted to this Share this post Link to post Share on other sites
ando76 4,354 Posted May 5, 2015 Yes I'll bite - never ever use a high volume pump on a crossflow - full stop. As for using an off the shelf oil pump - good luck. The JP pump I just did for a forum member on here was out to buggery and full of dags. Good luck with the Clarko carby also. I have found them to be a bit hit and miss and his jetting is way way way off and he wont be told otherwise. I know that he advertisers that he learnt off GT. GT was a mate to both of us and I have 3 GT meth carbys and all of them are way better than what Dave is building IMHO. I would put the fellers out there to see if you can find an old GT meth carby. They are out there. As for compression ratio - stick below 12:1 and run stock rods and acl cast pistons. Forged stuff is nice but really just so you can brag to your mate that you have a forged bottom end. Even with forged gear I would still stick to less than 13:1. Yes that is way different to what every other meth engine builder will tell you to run and hey follow their advice if you want to split the block - break main caps and generally fek your engine. Go easy on the comp and bang the timing in. Your old sump sounds good so go with those ideas. 1 Ando81 reacted to this Share this post Link to post Share on other sites
Corty1979 0 Posted May 5, 2015 thanks for the advice ando i dont really know much about xflows thats why im on here trying together as much info as possible with the oil pump what do you do with the standard pump then or does the standard one work just fine Share this post Link to post Share on other sites
ando76 4,354 Posted May 5, 2015 They work in a standard application - speedway hmm not so. I modify them to relieve at a higher pressure (set up for the application and package) and generally 'blueprint' them. Not really keen to give away all my secrets as it part of how I put food on the table. 1 Corty1979 reacted to this Share this post Link to post Share on other sites