Right, I have the 121 up and running again and this morning did the wheel alignment, setting them straight ahead. It has solved the squirming under acceleration issues and it is a lot more pleasant to drive now but one thing I have noticed is when you come off the throttle it will pull to the left. Under acceleration it will pull right, under engine braking it will pull left.
What are some ways I can reduce this because it is not something that I want to deal with at higher speeds if I can help it.
a.woodrow,
Nov 20, 3:22am
Maybe the toe is too neutral!
kevymtnz,
Nov 20, 3:33am
try a toe out of about 2mm
a.woodrow,
Nov 20, 3:38am
even more probably seeing as its not for on the road
the-lada-dude,
Nov 20, 5:01am
what about throwing the steering wheel away and using rudder pedals with toe brakes on each one !you'll be right at home then.nah, on second thoughts, keep the steering wheel as you'll need something for your body to impact against .
mugenb20b,
Nov 20, 5:05am
It sounds like your castor angles are out.
beblowin,
Nov 20, 5:10am
put up the toe/caster/camper figures from front and rear as well as tyre pressures after your alignment then I will post a response.
morrisman1,
Nov 20, 6:21am
Camber is 1.8° negative on the left and 3° negative on the right. Toe was about 10 minutes of degrees toe out.Caster is 1.2° but the back of the car is sitting ridiculously high compared to the front.
note: im just going to go remeasure the caster.
Ok second measurement came up as 1.0°. This seems unusually low but the car is sitting about 3" higher at the back than the front
morrisman1,
Nov 20, 6:48am
just measured the sentra and that comes out at 1.3° positive caster. I will modify my measuring technique and try again
skydog,
Nov 20, 7:59am
Hi Morris mana trick i learnt doing my sprite race carSit in the car when you do the wheel alignmentSolved some of my problems
smac,
Nov 20, 8:16am
Pulling left and right under power and brake is usually unequal caster (unless genuine torque steer). Most cars are relatively forgiving on the actual measurement, but must be equal side to side. However when you go swapping drive line etc the way you have you can also have some dodgy kingpin angle etc coming into play.
One other thing - why the hell are you engine braking! Go pedal for going, stop pedal for stopping.
lugee,
Nov 20, 10:28am
Design your own transmission with the diff in the centre.
the-lada-dude,
Nov 20, 6:30pm
sorry , but i've forgotten what sort of engine you have in this vehicle ! type,capacity !
mrfxit,
Nov 20, 8:00pm
Sort your alignments first then look at fitting a steering damper shock. Have a look how they are setup on vehicles such as Surfs etc
pge,
Nov 20, 8:21pm
I think you have exacerbated the situation by shortening one of the half-shafts.
There will be excess camber-change when under acceleration/deceleration, because of rise and fall of the drivetrain and chassis relative to the road surface.
There will also be a problem with the relationship between the arc-radius of the halfshaft and the arc-radius of the steering-arm on the same side.
morrisman1,
Nov 20, 8:50pm
I shortened both half shafts in the end. It is possible that you are right pge, I will try reduce the camber of both wheels as much as I can and will see where that takes me.
reading online most people speak of large amounts of torque steer when the mazda BP engine is swapped in, and that is only a little more powerful than the B6 that I have put in
smac,
Nov 20, 8:55pm
hmm.the thing is, although torque steer does exist, it is also often used as an easy explanation when things are swapped around. Been shagging about with over powered minis for years - some set-ups will 'torque steer', and some do not, which makes you realise it's not always the power. Just because some guy you never met plonked engine X into car Y and says he got torque steer as a result, doesn't make it fact.
tigra,
Nov 20, 9:23pm
Sounds to me like its partially a weight transfer problemparticularly under braking.
the-lada-dude,
Nov 20, 10:01pm
i'm thinking it,s weight transfer, with engine torque winding up your susp components. i'd change all suspbushes to a hard plastic or brass /alumin thinking you can measure down to 1/6 deg and thats gunna help is disney land. some where along the line that eng is twisting and pulling body & eng components with it.let alone torque reaction @ the wheels go check out the subaru body bracing kit ( eng compartment ) and see what i mean. whats your front springing rate ! front sway bar !
ema1,
Nov 20, 10:23pm
My 10cents worth morrisman I'd be willing to bet that the engine mounts and suspension bushes and general strength of the front regions of the body need a drastic beefing up! I'll bet the engine and suspension is moving around excessively causing the weird results plus wildly varying alignment effects you are getting there. Also plus spring rates and shock absorber control rates and alignment specs need to be worked out to suit, it needs to be thoroughly and extensively experimented with.
bill-robinson,
Nov 20, 10:32pm
The driveshaft arc should nor affect geometry unless the joints are bottoming out. Untill you get it all aligned and bump steered you are chasing the dragon.
the-lada-dude,
Nov 20, 11:50pm
are you the bill-robinson that worked for Benetton !
bill-robinson,
Nov 21, 12:16am
To the OP I think you need to get your prioities in order with regard to yoursuspension. Firstset the ride height then bump steer then corner weights then connect the roll bars then wheel alignment then test,test,test of course all this after a full and correct build and freedom of movement check.Get back after you have done this RegardsBill
the-lada-dude,
Nov 21, 3:24am
has it got a lsd ! double check it hasn't. these thingies can cause mayhem sometimes. & if it hasn't i'd think about putting one in once you'vesorted it out.
morrisman1,
Nov 21, 9:13am
Im just converting and uploading a video to show you what the torque steer is like. I think half the problem is the lack of self centering in the steering, with more self centering id be a lot more stable.
Since the public registrations are closed, you must have an invite from a current member to be able to register and post in this thread.
Have an account? Login here.