d.p Posted January 17, 2020 Report Share Posted January 17, 2020 Pretty sure that is fine. 1 Quote Link to comment
datzenmike Posted January 17, 2020 Report Share Posted January 17, 2020 The TDC must be set with the timing pointer. Lobes at 10 and 2 just confirms compression stroke and not the exhaust stroke TDC (there are 2 on a 4 stroke engine) and is no where near accurate enough. If you did use the timing scale at 0 (zero) the cam timing is perfect. 1 Quote Link to comment
mainer311 Posted January 17, 2020 Author Report Share Posted January 17, 2020 (edited) If you mean on the pulley, then yes. That’s why I said TDC on crank. I have a 6 notch pulley: -5, 0, 5, 10, 15, 20, and the 0 is noticeably deeper. Edited January 17, 2020 by mainer311 1 Quote Link to comment
mainer311 Posted January 17, 2020 Author Report Share Posted January 17, 2020 Thermostat housing is back on with a new t-stat and hardware. Then got all excited and put the exhaust and offy manifold on. 2 Quote Link to comment
banzai510(hainz) Posted January 17, 2020 Report Share Posted January 17, 2020 timing looks perfect to me 1 Quote Link to comment
WAGON JON Posted January 19, 2020 Report Share Posted January 19, 2020 Fun build so far. What's next? 1 Quote Link to comment
mainer311 Posted January 19, 2020 Author Report Share Posted January 19, 2020 Weber is on its way. Other than that, time will tell. I usually just make it as reliable as I can and then have fun with it. I think my next focus will be on the interior. 1 Quote Link to comment
mainer311 Posted January 20, 2020 Author Report Share Posted January 20, 2020 Well, stupid me broke the stock steel tubing for the manifold coolant return line. I heat it up red hot and tried bending it and it cracked, so I made a whole new line out of 3/8” heating oil fuel tubing. It has a flare fitting on the manifold and just slides into the stock rubber elbow on the pump side. I then cut the ugly orange plastic off of it. I used a “P” clip on the stock front stud to support the middle. I then managed to stretch my NOS PCV hose over to the new location on the Offy manifold. There’s a closer fitting, but it’s on the primary side in the back. I’d rather have it in the middle where it’s evenly distributed by the cylinders. I was asking about the fitment of the RockAuto radiator hoses a while back. Well, the lower Gates brand one fits awesome with the aftermarket radiator. 3 Quote Link to comment
mainer311 Posted January 22, 2020 Author Report Share Posted January 22, 2020 Weber showed up today. I turned the studs to the right length and loctited them into the manifold. Then I threw the carb on to make sure it fits. Of course, the install kit doesn’t come with a gasket that works, so I may just cut my own. One question though for any Weber gurus out there. This Offy is a split-plane, so I want to make sure the two circuits are separated, however this DGV has two holes in the middle. Is it okay to plug these? 1 Quote Link to comment
datzenmike Posted January 22, 2020 Report Share Posted January 22, 2020 I wouldn't. Probably for intake vacuum to operate the power valve. The Hitachi uses a hollow mounting screw. Which when rebuilding can be put back in the wrong place. My 710 was this way and when fixed makes a huge difference when passing on the highway. 1 Quote Link to comment
mainer311 Posted January 22, 2020 Author Report Share Posted January 22, 2020 7 hours ago, datzenmike said: I wouldn't. Probably for intake vacuum to operate the power valve. I had to scour the net for a while, but I found that the power valve vac port is to the outside edge of the secondary venturi. So now I’m wondering if these are just for casting purposes. I wish I could see to the bottom of them, but I can’t. Either way, these holes are going to sit directly on the rib of the manifold that separates the two circuits. 1 Quote Link to comment
datzenmike Posted January 22, 2020 Report Share Posted January 22, 2020 Usually stuff is there for a reason. I can't see this upsetting anything and it works properly on the stock intake. I've done things like this trying to out think the engineers. 1 Quote Link to comment
mainer311 Posted January 22, 2020 Author Report Share Posted January 22, 2020 @datzenmike I got a reply back from Weber. I think his grammar is worse than that of Ratsun! "these of no concernif you chose to seal them with a gasket which is commonhowever in common plenum manifolds ( large open Tub plenum if you will)they are used for things like additional timed vacume or power breakfittings and PCV." So, it looks like I'm just going to seal them over. He even said that on the DGV, most of the time the cast cylinders aren't even finished, so they aren't even cross-drilled or anthing. 1 Quote Link to comment
mainer311 Posted January 23, 2020 Author Report Share Posted January 23, 2020 I picked up an air horn from Pegasus Racing for the DGV. For the money, it’s a pretty nice piece of machined aluminum, and full radius to boot. 1 Quote Link to comment
datzenmike Posted January 24, 2020 Report Share Posted January 24, 2020 Wa ha ha ha I thought.... My respect for you has gone back up and +1. 1 1 Quote Link to comment
wayno Posted January 24, 2020 Report Share Posted January 24, 2020 So they are saying one can use something on that carb for a PCV or drill and tap something for a PCV??? 1 Quote Link to comment
mainer311 Posted January 24, 2020 Author Report Share Posted January 24, 2020 (edited) 30 minutes ago, wayno said: So they are saying one can use something on that carb for a PCV or drill and tap something for a PCV??? Yeah, I think I figured it out. Basically they use an intermediate spacer plate that is drilled and tapped for 1/4 NPT from the side, and then use a special gasket that redirects those ports. The guy was rambling on about “preconfigured kits,” and how certain carbs come with special adapters and additional machining if it’s required. He said in the K657 kit, those two ports are unfinished. The crappy part is that I’m adapting it to this Offy manifold, so half of the parts in the kit don’t work anyway. The good news is that it’s already jetted to all of the right specs, which I verified. Edited January 24, 2020 by mainer311 1 Quote Link to comment
bilzbobaggins Posted January 24, 2020 Report Share Posted January 24, 2020 50 minutes ago, mainer311 said: Yeah, I think I figured it out. Basically they use an intermediate spacer plate that is drilled and tapped for 1/4 NPT from the side, and then use a special gasket that redirects those ports. The guy was rambling on about “preconfigured kits,” and how certain carbs come with special adapters and additional machining if it’s required. He said in the K657 kit, those two ports are unfinished. The crappy part is that I’m adapting it to this Offy manifold, so half of the parts in the kit don’t work anyway. The good news is that it’s already jetted to all of the right specs, which I verified. What jets might that be? 1 Quote Link to comment
d.p Posted January 24, 2020 Report Share Posted January 24, 2020 Mainer didn’t you say you had no interest in a Weber because it sucked in hot air off the engine? Something about the cooler air from the stock intake was superior?? I could have sworn that was you. 1 Quote Link to comment
d.p Posted January 24, 2020 Report Share Posted January 24, 2020 Oh and what is an air horn for a carb? When people say air horn I think of those loud ass horns. 1 Quote Link to comment
mainer311 Posted January 24, 2020 Author Report Share Posted January 24, 2020 10 minutes ago, d.p said: Mainer didn’t you say you had no interest in a Weber because it sucked in hot air off the engine? Something about the cooler air from the stock intake was superior?? I could have sworn that was you. Yes, and I still think the same thing. 1 Quote Link to comment
mainer311 Posted January 24, 2020 Author Report Share Posted January 24, 2020 9 minutes ago, d.p said: Oh and what is an air horn for a carb? When people say air horn I think of those loud ass horns. Stub stacks, velocity stacks, ram pipes...they have many names. 1 Quote Link to comment
mainer311 Posted January 24, 2020 Author Report Share Posted January 24, 2020 So, now the fuckin accelerator pump linkage hits the intake manifold and the carb won’t bolt on w/o the linkage preventing the secondary from opening all the way. It appears that a phenolic riser is supposed to be under the carb so that everything lines clears. I guess I know what I’m doing tomorrow. 1 Quote Link to comment
mainer311 Posted January 24, 2020 Author Report Share Posted January 24, 2020 33 minutes ago, bilzbobaggins said: What jets might that be? See below. The only difference was that the idle jets were 55/55, so I bought a 50 and swapped it into the secondary side. Main Venturi: 26/27 Aux Venturi: 3.5/3.5 Main Jet: 140/135 Em Tube: F50/F6 Air Corr Jet: 165/160 Idle Jet: 55/50 Pump Jet: 50 Needle Valve: 2.0 1 Quote Link to comment
Stoffregen Motorsports Posted January 24, 2020 Report Share Posted January 24, 2020 17 hours ago, mainer311 said: I picked up an air horn from Pegasus Racing for the DGV. For the money, it’s a pretty nice piece of machined aluminum, and full radius to boot. Be careful not to disrupt the airflow with a filter that's too short. The lid of the filter needs to be at least 3/4" above the velocity stack, or you may as well not even use it. 1 Quote Link to comment
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