So the never-ending drama of my not being able to tune the new engine lead me to seek out some additional advice in places I normally do not ask questions. (I was really hoping to find someone local that could come out and go over the engine/configuration with me.)
Somebody from the COVVC group responded with some commentary that of course, contradicts what dozens of other people have been telling me for months, but I’m going to take it as a starting point to get the engine running reliably.
Basically, I am going to throw out the input/advice from the SCAT sales rep and others and just assume that…
- While the choice of components I built the engine from are solid, the “plus” part of “stock plus” does not warrant some changes,
- Going to the Dual IDF 40s is essentially over-carbing the engine given the SCAT C20 cam,
- The bigger valve heads are indeed being restricted in air flow by the muffler I’ve been running
Now every choice I’ve made has more or less been done by listening to others so what I have learned from building my first engine is that I should take everybody’s advice really with a grain of salt and that a lot of this will be trial and error. It sucks, but that’s what it all amounts to so far.
I decided to try to tackle the exhaust air flow first to see if changing that will ultimately allow me to leave the dual 2BBL carbs on and tune them.
I pulled out that simple cheap EMPI economy extractor muffler which caused me some fitment issues before. That was actually supposed to be the muffler for this build way back when.
With some bending and banging with a rubber mallet I was able to get it to fit and have it on.
I still need to secure the 2 adjustable pipes but I have no idea where I put the hardware for that. I’m thinking for basic start up I’ll just wrap some of that really nice JEGS silicone heat-resistant tape on it to seal the gap. That way, if it doesn’t easily tune and idle I’ll have spent less time.
Now this muffler actually has enough inner clearance to possibly mount the oil filter off of the #4 exhaust out. This would have it be vertical right there and easily reachable for replacement.
I’ll have to see how it pans out and if I want to cut those oil hoses to fit them.
One other thing I noticed about this muffler is that the pre-heat holes are already drilled, so I need to find me block-off plates to close these up. I put them away in some bin.
So I’ll see if this setup makes the engine idle better and the carbs tune properly.
If this fails to work, I’ll be…
- Leaving this muffler on, but tearing the 2BBL carbs off and putting the 1BBL EMPI EPC 36s back on. That’ll necessitate the moving of the coil again, or I suppose I can see if I can get those really ugly ICT/EPC style hex linkages to work.
- If #1 doesn’t become reliable, then I’m going to paint up the AE engine’s stock manifold and install that and a stock 34 Pict 3 carb.
I just need it running and good enough to go into Żuczek to make him mobile.