wagoon 2,429 Posted August 20, 2015 I have 2 diffs at home waiting for when I put my new motor into my sedan(crossflow with single rail) the ratios are 3.08 and 3.23. The car has 2.77 in it now and I will be using 14 and 15 inch tyres to find what suits the engine then put one of the diffs in. I have a diff lined up with a spool in it for racing that has 2.92 gears and I wont be changing them, again just going to adjust with tyres size. Changing 1 inch in tyre diameter is pretty close to moving 1 ratio up or down in diff gears, so if you have 2.92 and go down 1 inch in tyre diameter it would be similar to 3.08. Its not exact but it gives a pretty good idea on what the engine would be like with that gearing. Share this post Link to post Share on other sites
slydog 7,873 Posted August 20, 2015 Pft 3.45 for the win. I drive my ute with 4:11's around and its fine. Easiest way to slow a xflow down is expect it to be fast and pull to high a gear set without enough power. 1 Mustardxf reacted to this Share this post Link to post Share on other sites
Mustardxf 29 Posted August 20, 2015 Non of that really changed my mind. 3.45s aren't that low + they suit my cam. 1 slydog reacted to this Share this post Link to post Share on other sites
slydog 7,873 Posted August 20, 2015 Well not slinging on what Ryan has said but TBH people happily drive a OHC Falcon with 5 speeds and 3.23 and 3.45 and never complain even though they spend most of there time in 1-4 not 5th. I know when I went to 3.45's in my old 2V clevo that copped a basic hyd cam 2500 stall it was BETTER on fuel. So it was a V8 with actual torque like people say a 250 has...so why is the 250 not the same ? My advice is try em and if you don't like it,change em. Sell em off to pay for whatever you replace em with. Share this post Link to post Share on other sites
wagoon 2,429 Posted August 20, 2015 Well not slinging on what Ryan has said but TBH people happily drive a OHC Falcon with 5 speeds and 3.23 and 3.45 and never complain even though they spend most of there time in 1-4 not 5th. I know when I went to 3.45's in my old 2V clevo that copped a basic hyd cam 2500 stall it was BETTER on fuel. So it was a V8 with actual torque like people say a 250 has...so why is the 250 not the same ? My advice is try em and if you don't like it,change em. Sell em off to pay for whatever you replace em with. My person choice is my personal choice and I don't expect anyone to change what they are doing just cause of what I said, just mentioning a different point of view. I actually agree on running shorter gears as it's free horsepower and that's why I have 2 different diffs in the shed. My wagon with a 4 speed and 2.92 gears happily runs at 100km'h in 3rd so it could definitely run shorter gears which would help with bogging. I don't think short gears are a bad idea but by changing tyre size around instead of diff gears you can find out what the car is happy with and it can be changed for $50 and in 5 mins, that's all 1 slydog reacted to this Share this post Link to post Share on other sites
broken-wheel 659 Posted August 20, 2015 Take off is better, still needs a tune, gears are still to high I think and I think my float levels are to low as she after coming out of corners. has a bit of a thong slap My person choice is my personal choice and I don't expect anyone to change what they are doing just cause of what I said, just mentioning a different point of view. I actually agree on running shorter gears as it's free horsepower and that's why I have 2 different diffs in the shed. My wagon with a 4 speed and 2.92 gears happily runs at 100km'h in 3rd so it could definitely run shorter gears which would help with bogging. I don't think short gears are a bad idea but by changing tyre size around instead of diff gears you can find out what the car is happy with and it can be changed for $50 and in 5 mins, that's all problem with that is you gain or loos rake and messes up with CG for a tarmac car I run 3.27 and i reckon 3.45 would be perfect bar highway driving Share this post Link to post Share on other sites
gerg 10,871 Posted August 20, 2015 I did mention manual box.... auto is a different kettle of fish but anyway, take it or leave it. Share this post Link to post Share on other sites
wagoon 2,429 Posted August 20, 2015 Problem with that is you gain or loos rake and messes up with CG for a tarmac car I run 3.27 and i reckon 3.45 would be perfect bar highway driving I dont think its a good idea to leave the car with drastically different tyre size either. All I was saying was change tyre size to find out what diff gears suit instead of changing diff gears. Thats why I tried to explain about me using 14 and 15 inch tyres to find the correct final drive ratio. Once you find whats suits then change diff gears. The reason why I wont change the 2.92 gears in the diff for racing is because 17 inch tyres in common sizes range from 23 1/2 inches to 26 1/2 inches in diameter which means I can run many different ratios all with the same diff without changing gears. This isnt ideal but since I dont have money for a quick change 9 inch this is the next best option, according to me anyway 3 ando76, slydog and Mustardxf reacted to this Share this post Link to post Share on other sites
PRO250 1,506 Posted August 20, 2015 my old corty use to run a 262@50 cam and it would still pull the 2.92 gears no worrys I went to 3.9s and it was just a tyre turner and slower at the track on street tyresI dot agree or disagree with anything said but like rob said just try them and see what you thinkmy white car has 2.77s and will lay rubber in all gears and its cam is like 190@50 1 Mustardxf reacted to this Share this post Link to post Share on other sites
slydog 7,873 Posted August 20, 2015 I did mention manual box.... auto is a different kettle of fish but anyway, take it or leave it. We are talking about a modified engine and a guy who want to rev his car. Makes sense to change the gearing.Just let him try and if he doesn't like it he can change em. Share this post Link to post Share on other sites
Mustardxf 29 Posted August 21, 2015 So shit went down hill today, took my mates for a blast this afternoon.ended up with removing gearbox out.turns out the clutch doesn't like aggressive take offs and high revs,ripped the clutch right of the flywheel.so far looks to be the only damage thank god. 1 slydog reacted to this Share this post Link to post Share on other sites
Mustardxf 29 Posted August 21, 2015 You cursed me!!!! lol Share this post Link to post Share on other sites
slydog 7,873 Posted August 21, 2015 Nope just how it goe's bro...make each link stronger in the chain till only really big breakages happen LOL 3 Thom, Mustardxf and wagoon reacted to this Share this post Link to post Share on other sites
Mustardxf 29 Posted August 21, 2015 Yeah glad its happened this early on and 5 doors down from my house and not when I was out some backroad at night.Will asses the damage more tomorrow. Share this post Link to post Share on other sites
slydog 7,873 Posted August 21, 2015 And as boring as many may think a auto is,they just take soooooooooooo much more abuse and make the car faster to boot. Yes there dearer and you can't do clutch drops but they don't smash diff's and when fitted with them 3.45 gears and a 3000-3500ish stall it would still smoke em but go go fast when you wanted it too with out hurting the driveline. Just saying 2 wagoon and PRO250 reacted to this Share this post Link to post Share on other sites
Mustardxf 29 Posted August 21, 2015 Yeah Im hearing you, there has been thought about a auto! Share this post Link to post Share on other sites
slydog 7,873 Posted August 21, 2015 Expensive to set up but once done they pay for themselves in unbroken parts. Good convertor (which HAS to be matched to your combo) is around $1000 the auto it's self is only around $1000 usually and they need a good cooler and the lines shielded from the exhaust. I ran mine up the chassis rails but they need to go over the exhaust in 1 spot But in your case car load of people and too much traction = broken diff bits.A swap to 3.45's better chance of getting em spinning but 5 people and skids in 1 car don't work in most cases. Share this post Link to post Share on other sites
wagoon 2,429 Posted August 21, 2015 I completely agree with Sly on the auto, they are very much bullet proof these days and there really aren't that expansive when compared to buying good clutches at $400-$500. I even searched for a way to make an auto work for circuit racing, the only thing they won't do is down shift into a corner. So unless your circuit racing or drifting all the time (clutch kicks) a well sorted manualised auto will do just as much as a manual, as Sly said the car will be faster and the gearbox will be stronger. Then you only have to worry about diff centre,axles, engine mounts, tailshaft's etc Share this post Link to post Share on other sites
slydog 7,873 Posted August 21, 2015 Well...I know a guy who doe's killa engine mounts too 1 wagoon reacted to this Share this post Link to post Share on other sites
Mustardxf 29 Posted August 22, 2015 Ill give it one more shot with a manual and new clutch, if it flogs out just as quick I think a auto will definitely be on the cards.I already know of a tricked out c4 for a crossflow that I will get. Share this post Link to post Share on other sites
wagoon 2,429 Posted August 22, 2015 Well...I know a guy who doe's killa engine mounts too Yeah now that the bloke that designed them has nothing to do with them anymore they are much better 1 slydog reacted to this Share this post Link to post Share on other sites
Mustardxf 29 Posted August 22, 2015 This is a c4 I can get for $1500, probably a little less if I hustle him.stage 2 c4, cooling mods, performance bands, frictions, heavy duty snout on converter, r servo, new trans lines, new vacuum modulator), full conversion kit! includes lokar dipstick and kickdown, c4 magnum flexplate suit 250xflow, trans mount and rubber, bell housing for a 250 crossflow. Share this post Link to post Share on other sites
Xelisty 366 Posted August 22, 2015 People can be very stubborn manual men. I'm one too. Still with reasonable care they can do ok. Just load up the clutch a bit before dumping it goes a long way. 1 wagoon reacted to this Share this post Link to post Share on other sites
slydog 7,873 Posted August 22, 2015 People can be very stubborn manual men. I'm one too. Still with reasonable care they can do ok. Just load up the clutch a bit before dumping it goes a long way. I always thought my numerous rail's would last too...but they never did LOL 1 PRO250 reacted to this Share this post Link to post Share on other sites
