Did the rally 4 come with rear LSD?
You may need to alter the spring seats so the flat bottom of the spring sits correctly or if you were lucky the angle of the coil helix might match the spring seat and you can cut the flat ground section off of the springs.
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The spring seats are already flat itās just the rubber that covers the spring seat that is moulded to fit an open end spring, so I could modify the rubber or like you said cut the flat end off the spring to make it an open end.
First Iām going to take some measurements of the rear eibachs from the 2WD and see if I can get close to 350lbs by shortening them otherwise Iāll order the off-road coilover springs. Either way at this stage I have a few options 
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No only storia x4 there is a rear x4 lsd for auction at the moment Yahoo auctions
https://page.auctions.yahoo.co.jp/jp/auction/x495236927
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ok so I should be on the front end swap (motor gearbox kframe) this weekend.
still waiting on the bushes from mother Russia 
Im planning on installing a surge tank, idea being I can have minimal amount of fuel in the tank on track days to save a few kilograms and not have to worry about the motor leaning out during hard cornering.
Im looking at something small, probably about 2 litres, I think it should be big enough for the little 1.3
obviously a low pressure pump feeding the surge tank and a high pressure pump from the surge tank to the motor. Im thinking its probably an easier option than fabricating a custom intank reservoir/swirl pot.
I have a few questions regarding this, how much L/Min or L/Hour is recommended for the low pressure pump?
Do the inline type low pressure pumps have any problems priming when mounted above the full line of the tank, or should they be mounted below the full line of the tank so gravity helps?
Are there any good options for in tank low pressure pumps that I could just mount in the cradle in place of the original?
Are there any in line type high pressure pumps available that arenāt complete overkill like the 044?
as usual your help is very much appreciated 
Alot of motosport guys here use the standard intank pump to the surge tank, then either bosch 040 or 044 or Walbro 240 upwards from surge tank
Does yours have a fuel return line? The Sirion I had determined fuel pressure at the pump.
The intank anti surge pot I use is quite a simple thing.
Just about any external small fuel pump for a carb engine would pump enough volume as at any critical time for getting fuel to the surge tank it just has to move fuel and does not have to make pressure. Mounted lower rather than higher is my preference, but mounted closer to the fuel is even better. So in your case Iād go with a basic intank pump for a carb. It will be quieter and will last longer as it runs cool.
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Ok thanks for the info 
Iām pretty sure it has a return line, I remember seeing the factory fuel pressure reg mounted on the fuel rail so it must. Iāll check again anyway, Iām just thinking it could be a while until I can fit the tank and Iāve read a lot of posts lately about people having dramas with fuel pumps so I thought I might as well open the tank then I though I might as well do a small surge tank set up at the same time haha
I just had another look at the tank and there is no return line, as usual MrG you are on the money. I guess brazing another line to the cradle is as much effort as an intank swirlpot and doing it in tank would be cheaper so I think thatās road Iāll take now
Do you have any photos of yours, I donāt remember seeing any on your build thread?
Man I really want this, found a third party that ships to Germany but unfortunately I just booked flights to London and canāt afford it till the end of the month 
Im looking at making a short shifter, I also want to eliminate the bushes in the linkage completely and go for bearings instead. I think one of the idler pulleys from a VW diesel motor will do the job nicely.
The one circled in red, at a glance its about the right size to do the job and I think it can be adapted to replace the bushes and give a much better, more mechanical feel when shifting.
We do these timing belts all the time so we have heaps of old ones lying around.
I will let you guys know how it goes 
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I have been scratching my head for a while trying to figure out how to get a rear sway bar into the AWD, for anyone who is interested I think I have found a solution. I have a front swar bar from an A class Mercedes that looks like its the right width, and I also have the old Kframe from said Mercedes that I can salvage the mounts and bushes from. I should be able to mount the swaybar links to the lower shock mount using modified swaybar links from a BMW X5, one end has an M12 mounting bolt and looks like its long enough to replace the lower shock bolt. Ill cut the other end of it, tap a thread on it and do the same to the A series sway bar links and use long threaded tube to join them and give me adjustment. With the parts I already have Ill only have to buy a pair of X5 swaybar links and a little bit of fab work and I should be onto a winner 
I had this epiphany when working on a citroen C5, which used the same kind of system on the front, the bolt for the front shocks doubles as the mount for the swaybar link.
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It is certainly good for problem solving to see a variety of cars. I had the best look in, under and around an L251 today. Hmm, L251 A arms on an L200, not easy but doable. Had no idea until I saw how the rear of the subframe mounts.
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@Mr_Gormsby I have some questions about tuned length intake pipes. You are the only person I know who has played around with this idea so I figure you are the best person to ask.
I am planning on having a pod filter mounted in the front left corner of the engine bay where the battery usually sits and relocating the battery the the boot on the right side to help balance the driver weight.
I have been looking around on the internet reading various forums and articles, and the one thing they all have in common is the length. 13" starting point for a power band at about 6000 rpm, increase the length by 1.7" for every 1000rpm you want to lower the power band from the tuned pipe, and shorten it by 1.7" for every 1000 rpm you want to increase the power band from the tuned pipe.
I want to aim for more low down so a length of about 18" to 20" should give me an increase between 2000 to 3000 rpm. This will also allow me to mount the filter exactly where I want it, that is the easy part.
Now comes the part where I need your help 
there are 2 formulas for calculating the diameter of the pipe that I have found, one formula is
cross sectional area of the inside of throttle body + 25% = desired cross sectional area or the pipe. The throttle body I.D is 45mm and using online calculators to work it all out it tells me the ideal I.D should be 51mm, with off the shelf pipes I can get a 57mm O.D with a 2mm wall thickness giving me an I.D of 54mm. Pretty damn close. This is available in a 45Ā° bend with a leg length of 240mm so pretty much bang on exactly what I need.
The other formula says that the air velocity should not exceed 180 ft/sec at maximum rpm. The formula is square root of (cubic Inch x volumetric efficiency x maximum rpm) / (maximum air velocity x 1130) = pipe I.D
I have all the specs except for volumetric efficiency, so I used 85% for VE. which gave me this
SqRt (79 x 0.85 x 7000) / (180 x 1130) = 1.51" or 38mm. Off the shelf pipes have 1,75" or 44mm with a wall thickness of 2mm gives me 40mm, also pretty Damm close.
Here is where I need your help, what formula do you think I should I use? The second formula is for emingholtz resonance but to me having the intake pipe smaller than the TB makes no sense, but on the other hand maybe the other formula is wrong and the lager pipe wonāt be as efficient.
Iām hoping you might be able to help me or give me some direction, maybe you know of some other online calculators or you might have some people you could ask.
Iām also interested in how headers would affect the size of the pipe, if there is any way to match the intake pipe to the headers?
I know itās a lot of effort but I figure Iām mounting the filter in this location anyway I might as well spend a bit of time and make a tuned intake pipe, it could give me more torque and/or power without costing me any more money than I was going to spend on it in the first place.
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Hmm, a bit to reply to there. Might take a bit to reply to.
Placing a pod where the battery is - seal this area off from anything hot. It must draw cold air. That does not mean having big holes to the outside. You can pull the headlight out in front of where the battery sits and yet the pod might still draw hot air from around the engine or radiator. Shroud and seal things off 100%. Unless you are running 100mph donāt be to worried about any effect of positive pressure from forward motion. Just be sucking cold air (though having positive pressure does not hurt - nb the inverse is true for exhaust. The best place for exhaust to exit [unless meeting sound restrictions is an issue] is in a low pressure area).
Tuned pipe - hmmm. We normally calculate the length of a center line that goes from the valve to trumpet using software a friend has. Shorter lengths are good for throttle response and POWER. Long lengths are better for torque. And there will be a series of perfect lengths that match the wave frequency at the rpm where you want most power. The terminology to think of is pressure waves, ram effect and gas dynamics. Air going into the engine is interrupted by the valve closing. A pulse is sent back up the air tract. When it gets to another major change of some sort a wave bounces back down the tract. So you get a wave bouncing back and forward between the valve and the huge area change right where the runner finishes whether inside a plenum, air cleaner or the open atmosphere. At the sweet power spot in the rev range the engine sound changes. So what has happened is that at a certain length the wave frequency will such that it bounces off the valve goes up the runner, bounces off the atmosphere and arrives back at the valve when it is at max lift which helps cylinder filling. So your length formula will help get a rough idea of the correct distance from valve to atmosphere. This gets fine tuned in real life on road, track or dyno. So this was all about the runners of ITBs or the runners that go to a plenum.
In tuning pipe the bellmouth is also an essential consideration. But with a factory runner joined to the plenum as a casting might mean limited chance to alter. I wonāt cover that except to refer readers here to Prof Blair http://www.profblairandassociates.com/pdfs/RET_Bellmouth_Sept.pdf
[I will talk here about efi where air mixes with fuel at the valve. Carb and injectors mounted in and above air tracts are a diff story due to atomoisation issues]. The next length you are talking about is from plenum throttle plate to air cleaner? Or are you talking about making the runners (from the last paragraph) longer? You could do the latter jumping up in lengths that take into consideration the desired rpm and perfect frequency. I canāt remember what the K series plenum looks like. The EJ has virtually no plenum so I run a forty something millimeter pipe from the throttle body to a ram pipe inside a K and N motorcycle filter way down in the cool air in front of the radiator support panel and just above the ground. I went through the theory and up to some point it bought the max torque down lower in the rev range. Since it worked so well I kept going longer. Itās 1600mm now and I would say torque comes in at 2500rpm. When it was 1200mm long the torque also came in at 2500rpm. So the length to rpm torque change is not a linear curve. But going longer meant more torque at 2500rpm. The benefit is not to do with frequency but due to the inertia of the air. The bigger the volume of air which is throwing itself (inertia) at the engine the better the cylinder filling.
Pipe diameters - let me get this out of the way. As I explained with my car I have a, um, I think 44mm diameter pipe 1600mm long that meets at a throttle plate which is 39 or 40mm (canāt remember exactly) its axle is tappered along itās width to have only 3mm of its diameter prone to airflow (about half factory and with screws counter sunk and not exposed) and the plate has the part of the leading edge, which does no sealing, rounded and the trailing end knife edged (there is a more ovalised throttle plate to go in which is 41mm - such requires less angle to open and is less prone to hesitation when opening when the engine is producing vacuum). I am getting ram effect and low turbulance in the system. On the Nissan KA24 NA we have 50mm ram pipes and bespoke cnc manifold with an inlet tract length near 250mm on the ITBs. This opens to the largest plenum we could fit in the engine bay. The 2500cc engine produces well over 100hp/l. Theory said 49mm inlet was perfect. Dyno is telling us 51mm might be perfect. Max torque is desired around 2500-3000rpm which is being achieved. That plenum is approx 4000cc in volume to closely simulate the direct atmosphere. A sealed off K and N filter sits behind the LHS headlights where the battery once sat and feeds the plenum on the RHS via a kevlar 90mm pipe. The cross over pipe length in this instance is of little consequence. It is just there for a supply of cool air. In short, Iām not completely clear about your full set up. Are you doing a custom manifold? Or altering the piping from that pod to the TB and perhaps the TB itself? Yes as you said ātuned intake pipeā. I would do some real world testing using pvc pipe before committing to a final solution. Iād detail all the radiuses in the whole inlet tracks. Transitions from large to small cross sections are best served with tapper so not more than seven degrees to avoid flow separation and turbulence.
With the two diff formulas, two diff people have set their constants to align with beliefs they hold. Ususally but not always the calculation that takes the input of more variables will be more accurate. Let me digress some. Air speed should not exceed nor get to close to mach 1. Air ducts for subsonic and supersonic gas flow need diff design and in our engines we canāt have both. Point is we can have small diameter that work great by keeping air speed high, provided we donāt get to close to supersonic speeds. From the dyno stuff Iāve seen big engine ports are not as beneficial as smaller ones. A lifted or raised entry small port can be much much better than a big port. Shape is more important and the area just behind the valve is critical since this is where air speed must be highest. In fact some heads have worked better with ports reduced in size. High CFM flow is not as good as having the correct intake velocity speed. So what are those calculators doing? velocity or cfm. Note there are quite a few race car series that run restrictors. While going to small restrictors can mean power reductions they often find torque increases (eg http://rallycars.com/technical-stuff/fia-turbo-restrictors/). So yeah the throttle body can be smaller than the tract to it. Some TBs are to big anyway (remember running chokes in Webers?). And some TBās have so much restriction from axle, throttle plate, screws and holes off to the side that create turbulance that they need to be bigger than the inlet tract. Other thoughts to this is that TBs are placed before plenums. One wants higher than atmospheric pressure inside there and equal filling of all cylinders. Plenums are big and air speed is low inside them. The TB is just a volume filling regulator, Your smaller pipe will have more ram effect. Your bigger pipe might be better at WOT. Or it might be no better than the small one at WOT but lack the filling benefti fo the smaller one.
53mm instead of 51mm is a big difference. Donāt just think diameter here as the effect is cross sectional area. Iād have to punch capacity, cam duration, rpm, compression ratio and a heap of other stuff into a program to get a good idea. Suffice to say Iād machine the TB perhaps 1 or 2mm OS if there was enough material and lengthen the taper into it, machine the TP axle and TP, and counter since the TP screws (loctite and pein too). Going to really big TBs seldom works even with a lot of other mods. ITBs can be a diff story and they can be choked down (I think my calcs for the EJ 3cl was 28 or 29mm ITBs. I have some 32mm bike carbs which are way to big unless I can rev to 12 000rpm and then Iād have to run staged injectors with ones above the ram pipes for the higher rev range).
Iām not sure about free software. Sorry all my stuff is really expensive simulation stuff from work or friendās buisnessesl, much of which I am always struggling to really come to grips with how it operates since much of it is really complex.
Iāve prob waffled a bit. Itās cold by our stds tonight (Iāve lived through Canadian and US upper north winters but temp wise inside here is not much diff than being in a tent) and Iām tired. If you need clarification or something explained better just say so.
For now just ensure it sucks cold air, smooth transitions at all pipe entry/exists, big radius bends, long tube to air cleaner about the same ID as the TBās OD.
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sorry for all the questions, its probably a bit much sometimes. You have a lot of experience and youāve become somewhat of a go-to guy for technical questions like this. Ive learnt quite a lot in the short time ive been on this forum discussing things here with you.
Basically what I understand after my research is that its possible to size the intake pipe (from tb to filter) to achieve resonance at a specific RPM range giving a boost in power/torque in this area. This is Helmholtz resonance or Helmholtz theory. Its the same as sizing your runners and plenum for the IM, but on a 4cyl you have 2 pulses in the plenum/TB per rotation so you can take this further up the intake tract.
The rule of thumb for the length is always the same but the diameter has got me stuck. Searching the internet there seems to be 2 main theories or formulas used to work out the correct diameter, what I have written in my previous post.
Here are links to where I got my info.
http://www.team-integra.net/forum/blogs/michaeldelaney/130-intake-manifold-tech-runner-size-calculations.html
basically I would like to clarify:
- My understanding is length is the most important for achieving resonance at a specific rpm range, and the diameter controls air velocity. is that correct?
- do you know why air velocity shouldnāt exceed 180 ft/s?
- if the intake pipe I.D/cross sectional area is smaller than the TB will this choke the engine at high RPM even though there is high air velocity?
- the 2 formulas have given me different results, what do you think I should go with?
Basically the objective here is, I will buy a aluminium pipe to mount my pod in the front corner, I will make a shield/ airbox so its not drawing any hot air. I have a huge selection sizes of alu pipe to choose from. I would like to understand the theory here so I can buy the piece of pipe that has the highest chance of increasing power/ torque in the low to mid RPM range.
realistically I can make the intake pipe from anywhere between 1 inch to 3 inches in diameter, im just trying to work out in theory what is the best I can use and learn something new at the same time. With the set up im planning I will have about 10cm adjustment in length without cutting the pipe. And I already have a jig worked out for the hydralic press to press a bell/trumpet shape into the filter end of the alu pipe.
I would also like to clarify the meaning of ram effect, ive seen this phrase used to describe Helmholtz resonance and also to describe the the effect of an air scoop used on the outside of a car to force air into the intake at high speeds.
- Yes Iād say length is the most important since the induction pulses can be used to better filler the cylinder at specific rpm.
2.Not sure. 1100ft/s is supersoinc and that is something unwanted as air behaves in a strange and unpredictable way (so I read). - No. Itās a balance of intake length, plenum size, diffuser (the part between the TB and plenum) and so forth. Have a read of this https://www.livetodai.com/uploads/default/original/2X/5/53615496fa09c21947f01a1433055265f9147b16.pdf
- Concerning the two calcs - Long small diameter to move talk down the revs and short big diameter of the other calc to make more power albeit at more revs with a narrow power band. Iād say the calcs use some slightly diff maths to arrive at the answers. The complex equations require cam duration, valve size, surface roughness, and so on. Whoever wrote the equations would have chosen a diff constant to account for some of the variables they have not accounted for.
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Ram effect - here is some more light reading for you
http://www.profblairandassociates.com/pdfs/Back_to_basics.zip
http://www.profblairandassociates.com/pdfs/Bellmouth.zip
External scoops are good if they are completely shrouded all the way to where they are ducting air, mainly for the reason of a cold air supply. But then again at really high speeds they can make positive pressure. Think āabove 160km/hā.
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