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Search found 529 matches

by skinny z
Thu Feb 25, 2021 10:07 am
Forum: Engine Tech
Topic: Any downsides to anti reversion mufflers/devices?
Replies: 46
Views: 3109

Re: Any downsides to anti reversion mufflers/devices?

I wish I knew just how much volume was required because building large boxes sucks. Isn't that spec'd in one of his books? https://musclecardiy.com/wp-content/uploads/2016/05/1412.jpg That's a bingo! Of course this is all in an attempt to have open header mufflered performance. Or you can just crac...
by skinny z
Wed Feb 24, 2021 6:27 pm
Forum: Engine Tech
Topic: Any downsides to anti reversion mufflers/devices?
Replies: 46
Views: 3109

Re: Any downsides to anti reversion mufflers/devices?

RevTheory wrote: Wed Feb 24, 2021 2:10 pm I wish I knew just how much volume was required because building large boxes sucks.
Isn't that spec'd in one of DV'S books? Something along the lines of an empty muffler case per side of a typical V8.
by skinny z
Tue Feb 23, 2021 9:29 pm
Forum: Engine Tech
Topic: Any downsides to anti reversion mufflers/devices?
Replies: 46
Views: 3109

Re: Any downsides to anti reversion mufflers/devices?

For what it's worth CrateInsider.com's advice on the DynaTech/Hendren / Crate Insider AR "mufflers" is: "the longer the primary is, the closer you want the muffler to the collector; shorter primaries like 12-14" before AR muffler." They say on a 604 circle track crate they're worth 15-25 ft lbs bet...
by skinny z
Tue Feb 23, 2021 9:28 pm
Forum: Engine Tech
Topic: Any downsides to anti reversion mufflers/devices?
Replies: 46
Views: 3109

Re: Any downsides to anti reversion mufflers/devices?

digger wrote: Wed Jul 03, 2019 6:22 am they could potentially alter the pressure waves at certain rpms which may have negative consequences
Or possibly improve the pressure wave tuning no?
by skinny z
Sun Feb 21, 2021 1:55 pm
Forum: Engine Tech
Topic: Intake Port CFM and Cam Spec
Replies: 5
Views: 435

Re: Intake Port CFM and Cam Spec

Suitably thought out is pretty vague. Take a given intake port CFM and the installed CFM could vary by 50%; think a 2x4 race tunnel ram or IR injectors versus a single 600 CFM 4-bbl on a dual plane which will fit under the hood. Maybe, some might suggest you're starting at the wrong end of the pipe...
by skinny z
Sun Feb 21, 2021 12:41 pm
Forum: Engine Tech
Topic: Intake Port CFM and Cam Spec
Replies: 5
Views: 435

Re: Intake Port CFM and Cam Spec

Port flow CFM is very important. After calculated the flow demand for the engine, I need to calculate choke flow for the minimum cross-sectional area of the port. Most people don't know this spec, and if the port design isn't very good, the effective minimum cross-sectional area can be much less th...
by skinny z
Sun Feb 21, 2021 11:12 am
Forum: Engine Tech
Topic: Intake Port CFM and Cam Spec
Replies: 5
Views: 435

Re: Intake Port CFM and Cam Spec

skinny z wrote: Sat Feb 20, 2021 12:02 pm And once I post this there'll probably be some relevant threads to read over.
Surprisingly, there seems very little on the subject.
Perhaps this might be better posted in the DV forum as one of the programs I'm using is Torque Master.
by skinny z
Sat Feb 20, 2021 1:01 pm
Forum: David Vizard forum
Topic: Torque Master 90 Day Trial BBC Question
Replies: 2
Views: 116

Re: Torque Master 90 Day Trial BBC Question

Thanks for that Stan.
Well, at least the SBC stuff is functional and that's my primary area of interest.
Hopefully, it'll all come around eventually.
Thanks again.
by skinny z
Sat Feb 20, 2021 12:31 pm
Forum: David Vizard forum
Topic: Torque Master 90 Day Trial BBC Question
Replies: 2
Views: 116

Torque Master 90 Day Trial BBC Question

I've had quite a bit of time to mess around with the TM program using various data points of a SBC project.
Today, I went about a BBC spec and found that the BBC hasn't been coded yet.

BBC.jpg


Is this a free trial thing or a project still in the works?
Thanks in advance.
by skinny z
Sat Feb 20, 2021 12:02 pm
Forum: Engine Tech
Topic: Intake Port CFM and Cam Spec
Replies: 5
Views: 435

Intake Port CFM and Cam Spec

I've made the rounds regarding a cam spec for a given combination I intend to put together. Actually a couple as it may be a 357 or a 383. But this questions involves the heads, as they are, without any additional porting (other than a gasket match if needed). The heads will go on whatever displacem...
by skinny z
Sat Feb 20, 2021 10:58 am
Forum: Engine Tech
Topic: SBC valve geometry.
Replies: 23
Views: 1586

Re: SBC valve geometry.

What spring did you use for your sweep pattern?
by skinny z
Thu Feb 11, 2021 1:03 pm
Forum: Engine Tech
Topic: SBC valve geometry.
Replies: 23
Views: 1586

Re: SBC valve geometry.

Interesting read on the two methods.

viewtopic.php?t=56596
by skinny z
Thu Feb 11, 2021 11:03 am
Forum: Engine Tech
Topic: SBC valve geometry.
Replies: 23
Views: 1586

Re: SBC valve geometry.

That's a new one on me.
Does this include the typical stud mounted rocker as in a traditional SBC?
by skinny z
Wed Feb 10, 2021 11:34 am
Forum: Engine Tech
Topic: SBC valve geometry.
Replies: 23
Views: 1586

Re: SBC valve geometry.

I've a .100" longer valve in my RHS heads and the only way I could achieve a minimal sweep (< .040") and not run too close the exhaust side of valve stem was to use the Crower .050" backset trunnion rockers. Pushrod length didn't exceed 8.0, more in the 7.5" ( I'd have to check my records) but we ca...
by skinny z
Tue Feb 09, 2021 1:23 pm
Forum: Engine Tech
Topic: Distributor and carb options
Replies: 6
Views: 420

Re: Distributor and carb options

Very similar collection of parts namely: carb, distributor and 6AL box. 355 SBC with 236/242 and .550" lift (Comp XR 288HR). Static compression around 10.2:1. I absolutely run a vacuum advance and as mentioned have it connected to manifold vacuum. To aid in tuning I've an adjustable vacuum can as we...