128 RACING - Set up, Tuning and Repair...
Posted: April 17th, 2008, 10:06 pm
Hi Guy!
128 destined for racing now almost finished. Engine was started for first time yesterday night. After a short running in period the oil was changed and it was taken for a spin today. For Your information the car weighed in at 625 kg only!!!
First impressions:
Engine goes extremely well at higher revs - to put it mildly - even if it was not taken "all the way" - Yet....
The idle and bottom end - under 3000+- is a bit lumpy/rough with some hesitation and spitting back (all carb mouths equally bad) - especially when not fully warmed up. The idle was finally set at ca 1200 after turning out the idle jet screw about 6.5 turns...
1) This leads me to believe that I will need to increase the idle jet to 45
2) Or maybe advance the ignition a few degrees: currently set at 10` at idle as original
(I do not have a lot of experience very much about ignition - but this was recommended by "the mysterious someone" everyone refer to.....)
Your opinion highly appreciated!
Engine specs repeated here:
1290 cc SOHC
Everything fully flowed according to Your advice on forum
Slightly bigger exhaust valves
10,2:1 compression
Cams steel billet 10.5 lift actual, lift TDC 3.5, Lobe separation angle 106
Dellorto DHLA x 2
4-2-1 header into 1 7/8 straight through exhaust
Ignition (stock) 10`advace at idle
Jetting as recommended by GC:
DHLA 40 (no suffix)
Chokes 32
idle holder 9
idle jet 40
pump jets 40
emulsion tube 5
mains 120
air corr 190
More updated pictures descriptions will arrive after sundays race.
For full story regarding build take a look at:
viewtopic.php?f=5&t=1382
Engine bay - nearly finished
Car ready except for some minor details - weighed in race ready today at 625 kgs!!!
Genuine Dellorto jets for rebuilt DHLA 40 carbs
Best regards
Remi Lovhoiden
128 destined for racing now almost finished. Engine was started for first time yesterday night. After a short running in period the oil was changed and it was taken for a spin today. For Your information the car weighed in at 625 kg only!!!
First impressions:
Engine goes extremely well at higher revs - to put it mildly - even if it was not taken "all the way" - Yet....
The idle and bottom end - under 3000+- is a bit lumpy/rough with some hesitation and spitting back (all carb mouths equally bad) - especially when not fully warmed up. The idle was finally set at ca 1200 after turning out the idle jet screw about 6.5 turns...
1) This leads me to believe that I will need to increase the idle jet to 45
2) Or maybe advance the ignition a few degrees: currently set at 10` at idle as original
(I do not have a lot of experience very much about ignition - but this was recommended by "the mysterious someone" everyone refer to.....)
Your opinion highly appreciated!
Engine specs repeated here:
1290 cc SOHC
Everything fully flowed according to Your advice on forum
Slightly bigger exhaust valves
10,2:1 compression
Cams steel billet 10.5 lift actual, lift TDC 3.5, Lobe separation angle 106
Dellorto DHLA x 2
4-2-1 header into 1 7/8 straight through exhaust
Ignition (stock) 10`advace at idle
Jetting as recommended by GC:
DHLA 40 (no suffix)
Chokes 32
idle holder 9
idle jet 40
pump jets 40
emulsion tube 5
mains 120
air corr 190
More updated pictures descriptions will arrive after sundays race.
For full story regarding build take a look at:
viewtopic.php?f=5&t=1382
Engine bay - nearly finished
Car ready except for some minor details - weighed in race ready today at 625 kgs!!!
Genuine Dellorto jets for rebuilt DHLA 40 carbs
Best regards
Remi Lovhoiden