I need performance valve springs for my skoda 120

anyone who knows where to obtain some that will fit?

You don't need performance valve springs.....the standard double springs are good for well over 6500 rpm and you won't need revs like that on a 120 engine - it will run out of puff long before that. 

1 hour ago, petergarforth said:

You don't need performance valve springs.....the standard double springs are good for well over 6500 rpm and you won't need revs like that on a 120 engine - it will run out of puff long before that. 

thanks for answering :P

 

are you a 100% sure?

I have fitted a GT cam shaft, and I have read springs has bouncing trouble at high rpm 

I am absolutely sure....I am running a full race set up that revs to 7500 rpm and has 140 bhp and I still use the standard Skoda double spring set up. The 136 engine in MPI form used terrible single beehive shaped springs that break and bounce - the older iron head engines springs are much better. My engine runs an iron 8 port head with massive ports and throttle bodies......a 5 port 120 engine will stop pulling power before 6000 rpm even if you have head work done unless you fit a ridiculous race cam. I built a mildly tuned one last year with an SK2 cam, head work, exhaust and a Weber and it peaked at 5227 rpm. 

4 hours ago, petergarforth said:

I am absolutely sure....I am running a full race set up that revs to 7500 rpm and has 140 bhp and I still use the standard Skoda double spring set up. The 136 engine in MPI form used terrible single beehive shaped springs that break and bounce - the older iron head engines springs are much better. My engine runs an iron 8 port head with massive ports and throttle bodies......a 5 port 120 engine will stop pulling power before 6000 rpm even if you have head work done unless you fit a ridiculous race cam. I built a mildly tuned one last year with an SK2 cam, head work, exhaust and a Weber and it peaked at 5227 rpm. 

Sweeeeeet :P    U are my new best friend   where did U get the cam from ? 

I also have a weber carb Im just missing the intake manifold for it :/

 

I have attached some info on my cam

SK 22340.odt

Cam wise - the one on my race car was a re-grind done by Kent cams to 244 profile (which is the same as SK6 and an old Ford crossflow one). The cam in the 120 Rapid came from CZ but it also appears to have been a re-grind (I thought I was paying for new). The Weber on the 120 was a 30 BDIC which fits a standard Skoda manifold - I guess you've got a side draught 40? Your cam is a very mild profile....it's an SK1 or thereabouts (they run 1-7 with 7 being a ridiculous thing with no power below 5000rpm) 

yes the side draught one     he said I would gain abt. 10% power increase with a total std. engine

 

I really want to find this manifold :/   there was one on Ebay, but it was sold same minute I found it :/

and the 10% was from the cam ofcourse

A Weber 40 will drown your engine with that cam even with small chokes. You'd be much better with a much smaller down draught. 

 

14 minutes ago, petergarforth said:

A Weber 40 will drown your engine with that cam even with small chokes. You'd be much better with a much smaller down draught. 

Thanks :P... I will keep the std. one then

will I be in need of bigger jets?, I should be able to run it with the std. jets right?

If you are using an uprated camshaft - even a mild one - you should be able to put some more fuel in so slightly larger jets would be beneficial, easiest way is to use jet drills and drills them, but ideally you want someone who knows what they're doing to sort this - ideally on a rolling road so you can see what air fuel ratio is. I always found the Weber 28/36 to be a good carb to uprate to......not massive but will provide more fuel and fits the standard manifold

I might have jets from a 130 enginge..  ill check what their sizes are compared to the ones on my 120 :P

I have a problem :/   when I tighten the bolt on the crankshaft pulley, cranskhaft wont turn over :/

 

do you have any ideas :D?

 

I have only changed the bearings and timing chain+gears..  crankshaft is the old one

4 hours ago, Ahlmann said:

I have a problem :/   when I tighten the bolt on the crankshaft pulley, cranskhaft wont turn over :/

 

do you have any ideas :D?

 

I have only changed the bearings and timing chain+gears..  crankshaft is the old one

The thrust washers are probably not sat in their grooves.....there is a tab that needs to hold them in place too. 

 

Edited 14 July, 20187 yr by petergarforth

HAHA  awesome mate...   I found out both washers where on the outside of the crank case :D..  one of them had to be on the inside

it turns over beatifully now..

 

on monday im getting the cylinders head back from the shop :p 

cant wait to turn that ignition key :P

 

 

add me on facebook there will be posted some pictures

 

K. Ahlmann Pedersen

 

and thanks a lot for your advices

One more question:D.  These 4 nuts.. Do they need 55nm. Or only 28nm. It is not correctly specified in the haynes workshop manual:/

 

 

 

Without digging out the Haynes manual I can't advise on exact figures but I work in lb ft not NM and I add 10 lb ft to the Haynes figures. The nuts are not nearly as crucial as the bolts though.....you can pretty much do what you want and it won't make much difference. 

Okey thanks mate..

 

Just found out my new gearbox dont fit :/

 

I might have to move the gears from new to old one as the drive shaft connection is different :/..

 

this tool mps-111 that I have to use to dissmantle the rear brake drums...  Is a hammer Ok to use? :D. I have new bearings and brake drums:)

 

Drum came out from right side just by a finger touch :/  which means the slot on the drive shaft en torn...  Next problem is that the bearing house is stuck:/  

 

Any good tricks for it?

The drums sometimes do come off easily - it doesn't necessarily mean there is anything wrong. Gearbox wise.....I'm afraid I didn't build my own gearbox so I can't help. There are only 2 types though - trailing arm (usually 4 speed) and semi-trailing arm (usually 5 speed) and they aren't compatible without swapping over the driveshafts, rear arms and cross member. 

I got a 5 speed and the new gearbox is from a 130 rapid so the drive shafts are different :/

 

but the drive shaft and bearing housing are still stucj on there :/  very sad

1 hour ago, Ahlmann said:

I got a 5 speed and the new gearbox is from a 130 rapid so the drive shafts are different :/

 

but the drive shaft and bearing housing are still stucj on there :/  very sad

 

You must have a 120 L5 box which is a 4 speed box with a 5th gear added - they match up to the trailing arm set up - all other 5 speed boxes match up to the semi trailing arm set up. Why don't you just retain the gearbox you have? 

sync rings are damaged, but I will just swap the gears around on the two gear boxes  it should be possible 

 

but ofcourse I have to get it off the car first   which is a problem with these shafts :(