kpr

day 6 on the big valve head. Still a bunch of material to come out of the port entry. But everything works out a lot nicer starting with smallport head, even though this one has been pretty aggressively ported. Material needs to come out of the top where new port meets the head, which is just part of changing in to "high port" rest of it all lines up pretty close with nice even ports and spacing, unlike bigport head. Just a little zing here and there with die grinder will sort it

A day or so after that, decided to swap in another inlet cam. I only had one stock shim cam hanging around. being a 193b exhaust cam. which is a 278 advertised 8.5mm, pretty small in the scheme of things but bit of a jump up from the weak 232 7.1mm stock cams Just throw that in the intake side and happy days.. turns out the supertech valve springs and ti retainers i had hanging around, that i threw in this head. weren't agreeing with the stock buckets note the shiny ring around the edge. not the swaf, was rolling around on the floor before took picture stock retainer left. supertech right, bigger so can take dual springs lucky it didn't drop a valve. Was only an issue on the intake side as the valves had been tipped when it got a valve job. but must be super close still if everything was 100% stock. with shimless buckets, non issue also, as they have more clearance under them Pinched the springs and retainers out of the big valve head. Then done the super fun job of changing them in place. So 30min job into a day job, results 278 intake cam stock exhaust; Pretty good considering stock exhaust cam and ports. thats it for this head. It can stay on there until the other one is finished. which Ive already cut up. no going back now

Got this going yesterday, after spending way too long making a new throttle linkage /pull this is the most ive made on stock cams - 125kw, the 129kw blue is uncorrected. the dyno over corrects a bit. so on a cold day the corrected power is lower than the corrected power on a hot day. so probably around the 127kw mark. which is pretty silly on the little stock cams. head also has pretty much stock exhaust side, i just zing'd a couple bumps off. still has the og toyota valve job. So looking good to do the same to big valve head

Yep, once its proven itself for a little bit, will get straight into doing the same to the big valve head that come off it. hence why im testing it on this engine/car. same deal with the manifold setup, will go straight back on the big valve head. At the moment its holding torque/cylinder fill pretty flat till just after 8k. roughly should work out another 5kw every 500rpm, if can make it hang on flat. So if can get it to hang on till 9k would be amazing, but anything would be a win at this point

so the last few days went like this In that order. I found some pictures of that port and that hole wasn't there when i put the head on. so was thin enough, that in the 20 sec the engine ran, vac pulled what little material there was there out. managed to slide hammer the insert out, so could get tig down there to weld the hole. hole was in head not insert. Seemed to have a bit of material around the hole. so just a thin spot in the casting. fun times. but that's why this head is a test run

Heads back from shop getting intake seats cut done a diy head skim on the mill. this old junker head was surprisingly straight. .04mm pretty much cleaned the whole thing

not bad

Head is basically done, needs to go to the shop to get the seats cut, before can test run it. as valves are all wacky after putting the guides back in. Any 3sge (non beams) people on here with some intake valves hanging around? thinking about trying some in this head if it works on the test run made some fancy cam sensor mounts Put a digital scale on the mill, thanks to aliexpress.

Needed to figure out the manifold, before gluing in the port inserts in for good. Had a bit of acetal hanging around that i brought for another project many years ago. current adapter/ manifold is made of the same stuff. Makes for good thermal insulator bunch of excess material to come off and ports to be machined to size. but all bolts up

he will have a hard time getting it close to the cylinder head on a rotary. But anyway, I'd rather have a sensor that reads falsely low than high. Especially if running in a modeled fuel equation, that does fuel trims in the background. If iat reads low, engine runs a little bit richer. if reads high will pull too much fuel and run lean. No iat fuel correction, engine runs richer when inlet temps are hot. leaner when cold. Not ideal, but better than the other way around

Yep if the stock one is 2 wire, using same cables are fine as they will already be wired to said inputs. Can compare against the water temp sensor reading, when the car/engine is at ambient temp. to double check the calibration.

as above polarity doesn't matter. wire to a an-temp and sensor ground. link has plenty of calibrations in drop down menu that covers most of them. main thing with iat sensors is to mount them somewhere to minimize heat soak. a sensor that reads incorrect due to heat soak is worse than none at all.

good thing i got the machine with the head that tilts both ways, come in handy already Have a jig in vice to bolt the inserts into, so can machine them all the way through. makes it easier to get them all the same also Pretty close to size here Need to do some more math double check they are sized correctly. But pretty close on the inlet side also. Probably said in a previous post; Bigport heads, all the ports are on an angle. so my evenly space ports dont line up, even this far down. Most of it will come out once port whats left of them. but will likely end up with a few step downs here and there. Since the main goal is a test run for my smallport head. not interested in making angle ports. and if this head were to ever get big valves, enough will come out for seamless transition Angle makes the port entry look way bigger than it is

Got a bit more done on this head today. roughed out the start of the ports. figuring it out as go along. but the plan is, take out most of it on the mill then hand port the rest.

pretty much going to plan so far. machined these on the lathe then zing'd angle on them, same as head. need as much real estate here as possible, as port entry will be near top of the plates. hence the angle cuts