zorartic

Hey, That makes sense, thanks alot for your response. I'll check out the post and update when I've got her up and running : ) P.S. casting debris in the head ports and inlets were already taken care of during the rebuilt, hoping that wont be an issue Best

Hey everyone! I have a rebuilt 7K motor, which runs like a charm apart from the carb. I managed to get my hands on a 32/36 Weber DGEV but not on an adapter so I've been working on designing and manufacturing that myself. The problem is that I had managed to find extractors for the 4K, which is something very rare in my location. And unfortunately, they don't fit with the intake that the 7K came with, it has a set of intake + regular exhaust manifold that needs to go together due to a bolt pattern, so I stuck with the 4K intake + extractors on the 7K engine upon the advice of a couple of people. Now, when I'll be upgrading to a 32/36, I was told the adapter plate doesn't provide enough of a taper for optimum airflow and should look into porting the intake runners a bit, so How much would the flow potential be restricted by the 28/28 runners on the 4K intake What's better? A 4k intake matched to the 32/36 bores + extractors OR a 7k intake matched to the 32/36 bores + a regular exhaust manifold. While port matching, what measurements should I be aiming for in the runners, and then the adapter plate side? How tall should the adapter plate be? What's a good height to allow a smooth enough taper for the air to feed into the intake with minimal turbulence? Moreover, what about port matching the 4k intake to the 7k head, how necessary is that? How much does turbulence kill power gains from the bigger carb? Apologies for all the questions, there aren't a lot of experts on this topic around my area, and I wanna learn as much as I can myself. Cheers

Also! This is probably a stupid idea but as I mentioned, due to where I live nobody knows how to regrind a camshaft for higher lift and duration, the machine shops know how to work but have never heard of this process and none of them speak English. Now sending a cam to be reground to another country is stupid expensive taking shipping and the exchange rate into account, so I wanted to know how do I explain to a machine shop the specifications of having a cam reground if they’ve never specifically done one? I can show them videos but how do we know how much material to take off the base circle to reach the desired lift and duration? and how do we ensure that the all lobes are ground evenly by the exact same amount? Cheers

Thank you for your timely responses I will surely calculate the compression ratios although i believe the shop has finalized on the flat head being the best option. Currently on a stock 4K I'm running 92 octane most of the time, but once the 7K is built ill run 97

Hello folks! I’m a 20 year old getting a 7K motor rebuilt to go into my TE71 fastback, the mechanical work will be done by the shop but I live in a 3rd world country where there’s isnt much technical theoretical knowledge but stuff just works haha Now the head that came with my 7K (on the right) was said to be weak and had been faced so went out and sourced another one which was difficult, but the shop found one which is out of another engine and much better (on the left). However this new head seems to lack this depression cavity cutout around the valves as observed on the one on the right. My questions are: 1. What does this cavity do, are there different types of 7K heads with and without this cavity? 2. What effect will there be if I pair dished pistons with each of these heads, the old weak valve cavity one vs the new flat head? Cheers :)