Don Terrill’s Speed-Talk

To increase tumble you can focus flow on the long side filling in the roof to give a straight shot at the edge of the valve, and if you're game deliberately block short side flow. Toyota did this with their "dynamic force" engine series. I mean it wasn't the only change, but it was the maj...

I still vote for turbocharging what you've got and giving it sexy ferrari noises. Don't tell him what's in it.

If you built a system that had two check valves made from a piece of plastic and 1" plastic ball bearing, with breather filters on top, then yes.

What pcv valve were you running on that? I'm concerned that a stock one will open immediately at full throttle and I'll lose the vacuum that way

That's why I still wanted to use the pcv, so it's still got more or less expected "leak" around the throttle. Just use a pressure reducing valve on the crankcase inlet.

Well I'm at 240k km / 150k miles, there's almost certainly not perfect ring sealing going on. I expect the pcv valve itself would be part of not holding a vacuum though (attempting to open at low manifold vacuum). Any ideas on if that's actually a thing and/or how do I stop it from losing the vacuum...

So I've got a Suzuki Swift Sport (1.6l engine, 120hp, 11:1 compression) and I've decided I want to put a catch can on it, largely for detonation resistance reasons. And it occurred to me that while I'm in there rearranging the pcv system I could set it up to pull a slight vacuum on the crankcase for...

Most impressed with the OP's videos. Would love to see a test with his Vic Jr. tall vs an RPM air gap with the divider cut down. One thing for sure is, just because it's down on the flow with the flow bench doesn't mean it will be bad at the track. Still very very good numbers out of that head. Yes...

Are these heads good for forced induction? I can't help but think that with their super fast burn speed you could match it to a pair of small twin scroll turbos and be able to run comparatively high levels of boost on pump gas. Would make for a great truck motor that some of you 'Muricans say you want

Tom68 wrote: ↑Mon Dec 25, 2023 2:20 pm Merry Christmas, waking up to Boxing Day in OZ.

Supercheap sale day you mean?

Restrictor Turbo motor eh? Be a shame if you had REALLY BIG piping and end tanks and no blow-off valve for instant boost off corners kinda like that Ford WRC car did :p Very large plenum after restrictor, needs a bov tho. Antilag is class legal, but hard on the turbo & ex valves so use is limit...

Restrictor Turbo motor eh? Be a shame if you had REALLY BIG piping and end tanks and no blow-off valve for instant boost off corners kinda like that Ford WRC car did

:p

The problem with high weight transfer is that it it tends to oversteer under acceleration in turns from the difference in traction/normal force. This is an additional good point which I have to think thru. If you're already accelerating when the still turning, you're using some of the rear wheel tr...

Just throwing it out there (haven't looked into chassis setup much beyond the things you normally have adjustment for) but it sounds to me like you want decent weight transfer then, not just front to rear for the drag race, but left to right as well so you don't have the axle fighting so hard to go ...

Also notable, overlap might get you good scavenging and torque, but at less than full throttle you've also got a good path for reversion and reduced efficiency at part throttle.

No, it's a 1.6 Suzuki. I just want it to sound a little different for "impression ratio" reasons. An unequal length header adds a bit of lump to something that would otherwise just sound like every Honda with a fart can, especially considering it only does a bit under 7000rpm and not nearl...