1978 twin charge saab powered reliant kitten

[t5n2o]

so, will this be at ppc next week?

[froggy]

yes running or not im coming

[t5n2o]

yes running or not im coming

Excelent, I shall have a good look over it

[froggy]

Major re thinks after Mallory the main one is the supercharger is now off the car and it's back to pure turbo for the time being

It was in the back of my mind that the holset might be too big to work with the charger . We were hitting 2bar manifold with the holset at 12psi but the fuel map was based on fuel flow to support 500hp and the estimator in the tuning software was showing around 450 hp but afr was mega rich going into the low 10s so pressure v flow is a long way apart and it really needs to run the later t7 trionic management which is maf based . Looks like I need to go with a gt3076r bb unit so the compound is on the shelf while I concentrate on the running gear for a while .

The other issue was the panhard rod flexing under boost and with the beam stripped out it was running a lot of toe in and positive camber on the o/s so spent a day getting it spot on and beefing up the centre to take a pair of triangulated link rods to make it a 6 linked set up

The front hubs which clocked up perfectly turned out to get well out of shape once the wheel was bolted on causing horrendous wheel wobble have gone in the bin with some nice chunky aluminium ones in progress .

Good things are the charge oolong system works well and temps were perfect although I didn't get much track time due to the brake issues . Spring rates are ok at the front but 450lb rears are going on the back and the car will come down another inch once I have massaged the front inner arches to make room for more bump .


To make use of the water meth system the map for the holset is a lot more agressive on the timing side as we have a lot more headroom with the 750cc injectors and the spray to cover any midrange knock from the extra advance . Have to say Im looking forward to the monster boost as we were probably only making around 300hp at Mallory based on what the holset flows at 12psi.

Next on the list is power steering which Isn't an issue at speed but for general hooning about will make catching the slide a lot easier and allow me to run more caster to get some self centering back

The corsa b column seems to be the easiest choice as the rpm and road speed signals are compatible with the Saab so it will be speed sensitive and torque sensing for some quick sideways action .

[Renrut]

I don't know what the corsa B electric power steering is like but on other cars I've had with it I've found that when things get really twitchy it can be a bit slow to react and can even start fighting against you if the back end starts wagging.

[froggy]

The torque sensing coupling can be re set on the corsa column as that's the usual issue pulling to one side . The car needs to run quite a bit of caster for stability at speed which gives heavy steering for parking etc .
I looked at the mgf / mr2 systems but the corsa is plentiful and cheap plus the ecu is Mitsubishi so should be put together well .

[Relentless Rob]

If you're running a Stack can you wire the power steering motor to the speed sensor so it only works at low speed? That way you can have power steering when you park and feedback when you play.

[froggy]

Wiring it up to the Saab speedo head and engine speed output from the ecu gives the epas the right signals to work properly so above 30mph the system is off and only responds to torque input which it's unlikely to see unless it sees a big input . The big difference is il be able to Get the lock on with one hand and run enough caster to self Center . It's mainly to make the car useable on drift days as we normally use an e46 m3 which can be steered with the palm of one hand and it straightens up without any input due to the caster and power rack

[froggy]

lots of mods this month , to start with the old hx35 is gone and made a good sum on the bay so the new hx35 hybrid cost £80 plus shipping . to get the best from it the manifold is being converted to split pulde including keepint the sides divided right up to the ext gate valve . after some mocking up im going up to a 44mm gate which has v band fittings and some adjustment for preload to help tuning .

the nissan manifold would be a mare to vut up completely so its being modified keyhole surgery style and the long runner that comes in at 90deg to the collecter has had a tweak to turn the tube ino the collector at a better angle





the corsa b power column is done and makes the car a lot easier to drive especially at low speed .the speed sensitivity works as it should and the weighting can be altered by adjusting caster on the top wishbone til i get some decent self centering but it feels pretty good as it is .
the floating felling from the rear is pretty well resolved now after tieing the lower chassis rails together underneath the car to stop the panhard rod mount from moving but it need a horizontal link on the n/s to triangulate the chassis properly . lifting the front trailing arm mounts up by 50mm has made a differnce to turn in as the back end starts to come round on the brakes rather than load the front into understeer .

the rear mudgaurds dont fit after adding the 20mm wheel spacers so no option but to fit the rear body so its back to cag and spray foam for a while



after smurfing everything i own last time ive got a roll of mask sheet to make a bit of a booth this time .

[froggy]

made some headway on the body ,



getting a bit heavy to lift but i can still get it off on my own

the manifold is coming along nicely

the divider will carry on down the wastegate pipe right up to the valve to stop any flow mixing .

this runner came in at 90deg but now turns in a bit better

internal finish was pretty poor but it was a cheap ebay job

divider in place

[froggy]

must be getting better at prep as it only took 1.5 litres of colour to get some shine this time

[mjslonergan]

That is looking very tidy

[froggy]

split pulse manifold finally finished just need to build the outlet pipe to merge back into the downpipe and a sturdy brace for the new turbo


both sides of the manifold are separated right up to the valve in the ext gate

[Rob Bell]

Have to say that looks amazing!

[froggy]

back on the road and first impressions of the turbone are pretty good , spool starts at 3300rpm and im on base boost of 1 bar at 4000rpm .as usual there are a couple of things i want to change namely the box for a 4.05 diff now i dont have the supercharger,s help . that brings the top speed down to the 140mph mark but will make a big difference to response and keeping it on boost changing gear .