Skoda Favorit Tuning Help Required

[LewisT]

Hi there, I have a 1.3 J reg favorit I am planning on doing up.

I am going to go for a trackday/rally kind of an idea.

I have the breaks and suspention in hand (aftermarket brakes and the suspention from a desiel felicia cut down!)

I do however need some help with egine tuning.

I am trying to find an uprated oil and water pumps for the engine.

I have two tuning options. the first is mate a 2ltr desiel turbo charger to a new carb or throttle body with an intercooler, or the second is to go high compression.

For both of these options i am going to need to uprated the oil and water pumps, but i just can't find anything out there!!!!!

I would greatly apreciate any advise on the above two options as well as any ideas about the oil and water issues!!

Thanks in advance

Lewis

[TeflonTom]

to be honest mate, the oil and water pumps should be fine for anything you throw at them...

is your favorit carb or fuel injected???

i would suggest using a fabia 1.4 mpi bottom end with a lairy cam and twin carbs, dont bother with a turbo, it will just cause you endless troubles

[LewisT]

Ok thanks for that.

I have been shying away from the idea of a turbo!!

I think an oil cooler may help a lot, what do you recon?

Fabia or Felicia bottom end??? what is the difference between that bottom end and the standarb bottom end????

What do you think to skimming the head to increase comression.. I am going to add a custom exhaust, and port and polish the head...

Thanks

Lewis

[TeflonTom]

the fabia has a 1.4, and the felicia/favorit is 1.3, so using the fabia one will give you an extra 100cc.

there's no easy way to explain this, so here goes!!!

skimming the head to increase compression is one way to gain a little, but to be honest it's probably not worth it, it's all swings and roundabouts. without trying to blind everybody with science.......

it all comes down to octane ratings of the petrol and the voluetmetric effiency of the engine, theoretically approximately 9.5:1 will give you the maximum efficiency using unleaded fuel assuming you have a 100% volumetric efficiency, but as we all know, only supercharged engines have anything near (or more than 100%) that, if for example your if compression ratio is 15:1 but your VE is only 66%, your 15:1 now becomes 10:1, this is how many manufacturers 'get away' with using high compression ratios for thier modern engines.... the other thing to consider is that at different rpm the VE is also different, so at 1000rpm it may be 50% VE but at 5000rpm it may be 40% VE..... now most car maufacturers design the intake of thier engines and set the compression ratio so that they get the highest possible VE at cruising speed (60 - 70 mph) because that's where they do the most work on motorways and hence gives the best fuel ecomony, now the downside to this is that at certain points elsewhere in the rev range the compression ratio is either too high or too low, this is what the knock sensor is for..... when the compression ratio is too high the engine will pre-ignite the fuel mixture (pinking) so the knock sensor will detect this and pull back the ignition advance untill pinking stops..... it is a well known fact that an engine will make more power with more ignition advance and less compression at any given rpm........

this shouldn't stop you from trying things like skimming the head tho, but bear in mind that shaving .5mm from a head will only give you about 1% power gain, and in some places in the rev range you may actually loose power, also certain engines also start to suffer from head gasket sealing problems because the annealed surface from the aluminium casting has been ground away to increase the compression.......

the other problems you may encounter is the cylinder head bolts may now be too long and they might bottom out in thier holes and may require grinding, also great care must be taken with piston-to-valve clearance... dont just assume there is enough room for the valves to move! remeber the pistons move faster than the valves!!!

my advice is dont spend too much time polishing the the ports or combustion chambers, spend more time cleaning up the area under the valve head (valve pocket).. but if you do want to polish it, dont polish the intake side to a mirror finish becuase this can cause fuel propogation problems

[LewisT]

Ok i think i have got that!!

Sorry, i forgot to mention that my car is on a carb!

Ok, so my current thinking is...... new full exhaust system + manifold... big bore free flow (probably custom made by me! (welder and pipe bender!!!!)) possibly new intake manifold to mate with either one big carb or two smaller ones, get the camshaft re-profiled, uprated fuel pump if needed, cold air feed to the carb(s), maybe a slight head skim, oil cooler, maybe some new valve springs with a gentle port and polish of the head and valve pockets!

how does that sound??

I am still tempted to just nail a turbo on and see how much power i can get before it blows, then nail in a VW polo G40 engine!!!

[ugluk]

Were you aware there are proper suspension kits available for the favorit from HP sporting, as used by the majority of favorit and felicia rally cars - available at reasonable prices from CZ - Ive been using HP kit for year for rallying.

theres a weber replacement carb available for carb model favorits (something like a dmtl from memory) Its listed as the replacement carb for vw golfs and sciroccos fitted witht he pierburg 2e3 carb - which is what the favorit had, should be able to pick one up on ebay cheap enough. The weber carb gives it some help on the breathing side. Its worth removing the centre box from the exhaust and replacing the rear box with something a bit more freeflowing - I like janspeed boxes myself - nothing huge is needed.

Why the limitation on tuning options - is it money or some other reason? Theres some very good very reasonably priced kit available from CZ.

[ugluk]

A couple of links to CZ stuff, should be able to find a currency converter around, theres a guy who imports special skoda bits to the uk called john shelley.

HP sporting - Ing. Ota Hu

[LewisT]

Nice one, i have been tryling to look for some CZ sites but i was having trouble for some reason!!! that is JUST what i was after..thanks!!

Lewis

[LewisT]

I had a look at HP sporting...... WOW how much!!!!!!!!!!!!

I will stick with desiel felicia strings and shocks cut to fit...

over £700 for a set of front and rear springs and shocks plus vat plus shipping..... thanks for the link but thats about 7x how much the car is worth!!!!!!!

The whole point was keep it cheeeeeeeeeeep!!!!!!!!!!!!!!! but still get lots of power!!

Thanks

Lewis

[TeflonTom]

Ok, so my current thinking is...... new full exhaust system + manifold... big bore free flow (probably custom made by me! (welder and pipe bender!!!!)) possibly new intake manifold to mate with either one big carb or two smaller ones, get the camshaft re-profiled, uprated fuel pump if needed, cold air feed to the carb(s), maybe a slight head skim, oil cooler, maybe some new valve springs with a gentle port and polish of the head and valve pockets!

!

dont bother with a re-grind, get a new one ground from a blank.... the reprofiled ones dont last long, i personally would go for DCOE/DHLA style twin carbs, and the smaller the better, have a look on ebay for DCOE carbs.... my advice is dont go any bigger than about 36mm chokes on a 1300cc engine.. oil cooler is a good idea.... dont bother with an uprated fuel pump, it can handle all you will throw at it 5x over

[ugluk]

I had a look at HP sporting...... WOW how much!!!!!!!!!!!!

I will stick with desiel felicia strings and shocks cut to fit...

over

[LewisT]

Brakes wise i was going to go for some new disks, like the brembo ones with some good pads and maybe some braded brake hoses to help with feel!

Ok so a fresh grind cam is a better option that a re-grind.. any good sources for uk based cam profiling people?

I found the cheep springs, how do they work out with the standard shocks? what sort lowering does that provide? I am more after a lowered track car than a rally car at the moment!!

A set of small twin DCOE carbs sounds like the ticket!!

O, going back to the brakes, i currently have a BIG problem with the brake byass, its like braking with the handbrake all the time... it locks the back wheels up before the front, and the haynes manual doesn't offer any brake byass adjustment tips? any ideas?

thanks

Lewis

[ugluk]

Theres two regulators on the side of the master cylinder I would suggest one of them is knackered. Probably the one for the front blocking more pressure than it should. Theres no way to "adjust" the bias on the standard system, but if you rears locking up first theres something wrong with the system.

Be careful when buying braided hose kits theres a lot of places that will tell you that you need a 3 line kit - they are wrong, you need a 4 line kit and goodridge have got some bad information on their system. All favorits apart from the vans I believe need 4 line kits.

I believe Kent cams are used to doing Skoda cams these days. Although I believe the profiles they offer are normally based around rally group N \ A useage and so are designed to work with down draught twinchoke carbs not twin 40's although they may also have profiles to suit twin 40's. I used to get cams made up by local engine builders from a blank cam, as at least then the cam will be what you asked for.... Ive heard some interesting tales about cams varying from stated specs.

Personally I dont like DCOE's I dont like the way they run at low throttle openings, too low airspeed for my liking, I far prefer progresive twin chokes on down draughts where you get high airspeed at low throttle openings and plenty of flow wide open. Ive just never seen dcoe's setup optimally for both driveability and maximum power. its normally one or the other.

Whether for rally or track use you won find any better suspension for the favorit than the HP on the affordable side Pro-flex .

I dont like using lowering springs on standard shocks as it over heats and kills the shock absorbers faster. For fast road use though on a new set of shock absorbers you could still be looking at 5-6 year life span from a new set of shocks with a car being lowered a couple of inchs on new springs. Many people they wont feel any problems with the setup. Proper lowering springs on standard shocks though is better than cut down standard springs on standard shocks. Ive not seen a set of home cut springs I would drive on yet.

[TeflonTom]

I believe Kent cams are used to doing Skoda cams these days. Although I believe the profiles they offer are normally based around rally group N \ A

if they can grind these cams, it might be worth consulting them and getting a custom grind done for your engine, these normally cost around about the same as an off the shelf cam

Personally I dont like DCOE's I dont like the way they run at low throttle openings, too low airspeed for my liking, I far prefer progresive twin chokes on down draughts where you get high airspeed at low throttle openings and plenty of flow wide open. Ive just never seen dcoe's setup optimally for both driveability and maximum power. its normally one or the other.

it's for this reason i allways tell people to get the smallest carbs possible, hence higher airspeed, and better fuel metering...

i would also try to avoid downdraught carbs for this application because you will have problems with hitting the bonnet, and all of the dcoe/dhla manifolds i've seem are all sidedraught ones anyway

[LewisT]

downdraft might be good, get a coulple of itg stick on filters, and have them poking out of te bonnet with a scoop.... plenty of nice cold air!!!!!

[ugluk]

I think theres some confusion over this by down draught I am talking about progressive twin chokes on down draughts I am talking about the throttle opening mechanisms or carbs like these :-

carb

The way the throttle works basically it only opens one choke to a certain point then suddenly opens both chokes fully, gives superb airflow characteristics high airspeed at low openeings and lots of air at greater openings.

There shouldnt be any bonnet clearance problems with one of those carbs they are a direct replacement item.

The problem with weber DCOE's is that they are only designed for unrestricted airflow you can mitigate this by going smaller on chokes but at the same time you are cutting of the unrestricted flow they provide top end, you can achieve a degree of balance but no amount of rolling roading has ever given me as much driveability or low end torque from a set of dcoes as from a downdraught type carb. I have seen massive hp figure improvements due to better flow at the top end on full race engines, which on a side note led me to the idea to use two downdraught carbs to give the same maximum flow potential whilst retaining the progressive throttle design an idea I came up with 8 years ago, and got a funny look from another skoda club member when I mentioned it as he had just designed a manifold to do exactly that on the advice of a friend who works on F1 engines The manifold has been made up but the engine to test it on is in pieces. One day I will see if that idea works .

[TeflonTom]

I think theres some confusion over this by down draught I am talking about progressive twin chokes on down draughts I am talking about the throttle opening mechanisms or carbs like these :-

carb

ah yes, i see what you mean now..... those are very good replacements, and quite a lot of extra power can be gained from fitting one like that.... you have to choose your jets very carefully tho:)

[andyhindle]

Hi, my friend has a 2" Powerflow system for a Skoda Favorit in great condition, and I have a 1998 Skoda Felicia 1.3 L. Does anyone know if this exhaust will fit correctly? E.g. same engine block size, etc.?

Cheers