I built a nice lively 8v for a mate , GS2h , ported and polished head , with reshaped valves ,3 angle seats etc , TSR 4 branch and a free flowing system . Now he wants to fit twin 45s , that we know came from a good home (off an 8v Scirocco , professionally set up) . Realistically , will they free up much more power?
Waaaaaaah!!!!!!!!!!!!!!!! Ran several 8v on 45's over the years and loved them all. Racing and rallying not the school run... Depends what plan the overall car fits into Jon
Fast road fun, hammering the lanes and track days. I fitted big brakes, and set up a nice Koni coilover kit on it.
All depends how you look at it Tris. On that spec, std kjet will cope with ease...around 140hp? Carbs would add around 10hp or a little less at that power level...depending how well the kjet is set up. What they "will" do is pave the way for a more radical cam choice. . .and like Jon said, they'll sound the part! The only issue is the need to port match the inlet manifold to the head. .which means the head needs to come off.
Other issues, induction roar inside the car can be wearing without a hat on. Air filtration tricky. You will use more fuel. In your situation if there were any significant road miles involved I would keep modding your engine on kjet until the kjet ceases to effectively work, then fit carbs Jon
45's are like buying gold, a good set is not likely to go down in value anytime soon Jon Pay the extra, if they are cheap there is usually a reason
No shortage of that then Tris! But bare in mind the port matching exercise or the power gains will be disappointing. You can get 150-155hp on digi with a cam up from what you have...276 newman or piper 285 (also 276 duration) on a 2ltr...not much less on an 1800. Carbs on a mk2 also needs the servo removing to clear the trumpets.
As the car is running the OE Digifant 2 engine controls, without a custom map on both chips will be rubbish now. Open induction by itself ( all other things being equal) can increase airflow at higher engine speeds, yes, which can lead to more cylinder pressure, torque and power. My question is when you go to carbs, how are you going to control the spark timing which is not brilliant for a 1.8 stock engine. You said the digifant will be removed?
I've recently converted an ABF to twin DHLAs, I used an old Saab dizzy. This sort of thing. http://www.ebay.com/itm/Genuine-Saab-74-85-766-Ignition-Distributor-/131382782488?fits=Make%3ASaab|Model%3A900 Because it's Bosch and uses the same hall effect sensor as VW I was able to use the stock coil and ignitor from one of my other project cars. From memory there's a similar dizzy on an old carby Polo but we never got those here. It gets real close to the master cylinder though.
Oops I got carried away and forgot this thread was about 8v motors Here's an 8v solution from my old race car. Mk2 golfs here came with carby motors, I had the dizzy from one of these professionally rebuilt and modified to run mechanical advance only Curve starts at 1200rpm, 16 @ 2700 and 22 total in dist @ 4500. Static advance to be set at 10 BTDC giving a total advance of 32 all in by 4500. By that stage of the car's development it was a solid lifter 1800 kJet head (with the injector ports blocked off) on top of a 2.0 2E motor. I had to make a spacer to adapt the early dizzy into the later block.
