Speed-Talk is running on www.Speed-Talk.com

IMPORTANT: Update your bookmarks to https://www.speed-talk.com/forum/
(Right-click the URL and select "Bookmark this link")

Search found 1632 matches

by panic
Tue Jan 31, 2023 11:59 am
Forum: Engine Tech
Topic: vacuum advance goes to manifold vac?
Replies: 26
Views: 2057

Re: vacuum advance goes to manifold vac?

Once the throttle is cracked, the ported and manifold vac's effectes are the same This does not happen immediately on tip-in, but when the throttle disc's edge passes the VA port. This is determined by how high that port is above above the transition port (or the top of the slot). In certain carbur...
by panic
Mon Jan 30, 2023 11:39 am
Forum: Engine Tech
Topic: Low speed (1500-1800 RPM) driveability issue
Replies: 145
Views: 8142

Re: Low speed (1500-1800 RPM) driveability issue

Your manifold's divider wall is almost gone.
Close it up. Instant vacuum improvement.
by panic
Sun Jan 29, 2023 11:32 am
Forum: Engine Tech
Topic: Alternative fuel enrichment
Replies: 18
Views: 677

Re: Alternative fuel enrichment

Stoichiometric means chemically correct. All energy present is liberated. Running WOT @ 14.7:1 (by weight, since gasoline weighs approximately 640 times as much as air, the proportion by volume if fully vaporized is about 9,400:1) leaves much power on the table . Light tip-in at cruising speed @ 14....
by panic
Fri Jan 27, 2023 11:56 pm
Forum: Engine Tech
Topic: Selecting a compression ratio
Replies: 24
Views: 973

Re: Selecting a compression ratio

Even with all my errors, which of you already posted that DCR results may vary widely?
[crickets]
by panic
Thu Jan 26, 2023 5:49 pm
Forum: Engine Tech
Topic: Mating Two V8's, ( Freight Train) vs. Harmonics
Replies: 25
Views: 1047

Re: Mating Two V8's, ( Freight Train) vs. Harmonics

W/r/t V12 crank to fit 2 X V6 blocks. The correct timing interval is the usual 720° ÷ number of cylinders = 60°. If the V6's cylinder bank angle is 60°, you're good. If they were early Buick V6 (derived from the small Buick V8) at 90° adjacent crank-pins must be offset by the missing 30°. More of my...
by panic
Tue Jan 24, 2023 10:40 pm
Forum: Engine Tech
Topic: Mating Two V8's, ( Freight Train) vs. Harmonics
Replies: 25
Views: 1047

Re: Mating Two V8's, ( Freight Train) vs. Harmonics

Gene Adams, one of the greats, passed away last year.
by panic
Tue Jan 24, 2023 6:34 pm
Forum: Engine Tech
Topic: Mating Two V8's, ( Freight Train) vs. Harmonics
Replies: 25
Views: 1047

Re: Mating Two V8's, ( Freight Train) vs. Harmonics

Herbert did a 2 X 400 SBC, and remarked that he thought the bad vibrations were due to separate distributors. He was looking fo a Marmon, etc. V16 distributor.
by panic
Sun Jan 22, 2023 6:34 pm
Forum: Engine Tech
Topic: 8.2 Deck Dart/World Windsor longest stroke possible?
Replies: 23
Views: 906

Re: 8.2 Deck Dart/World Windsor longest stroke possible?

The 8.20" deck had a single purpose: to fit under the hood of a Falcon, I'm sorry, Mustang.
If you have the room, the taller deck reduce problems.
by panic
Sun Jan 22, 2023 12:08 pm
Forum: Engine Tech
Topic: Chamber Mods vs Gains
Replies: 19
Views: 702

Re: Chamber Mods vs Gains

An old rule: "if it doesn't breathe well, compress the h*** out what you can get".
by panic
Sat Jan 21, 2023 9:58 pm
Forum: Engine Tech
Topic: Modifying chambers for boost
Replies: 10
Views: 422

Re: Modifying chambers for boost

My 2JZ 3 liter makes about 520 hp at 17 psi with the stock head.
by panic
Sat Jan 21, 2023 2:42 pm
Forum: Engine Tech
Topic: Chamber Mods vs Gains
Replies: 19
Views: 702

Re: Chamber Mods vs Gains

Flow bench tests give results at all lift levels.
Do they test at every piston position 40 degrees B/ATDC with the actual piston in place? Then it won't show up on a test.
by panic
Sat Jan 21, 2023 2:11 pm
Forum: Engine Tech
Topic: Modifying chambers for boost
Replies: 10
Views: 422

Re: Modifying chambers for boost

What does a prepped 2JZ-GTE chamber look like?
by panic
Sat Jan 21, 2023 2:08 pm
Forum: Engine Tech
Topic: Chamber Mods vs Gains
Replies: 19
Views: 702

Re: Chamber Mods vs Gains

#1 reason for sharp edges in prepared heads?
Highly $killed labor needed to finish them.
Once the piston drops ATDC, the huge shape & volume change disturbs flow into the cylinder.
Greatest effect @ low lift, helps most if the OL window (valve lift X degrees open) is too small.
by panic
Thu Jan 19, 2023 12:35 pm
Forum: Engine Tech
Topic: 8.2 Deck Dart/World Windsor longest stroke possible?
Replies: 23
Views: 906

Re: 8.2 Deck Dart/World Windsor longest stroke possible?

Math: Stock 289: 2.87" stroke, 2.249" mains, 2.123" rods has traditional OL [ (main + rod - stroke) ÷ 2] ) as .751" (linear inches). However, GM and others use a more complex formula to calculate the actual shared cross-sectional area (shown here: https://mathworld.wolfram.com/Circle-CircleIntersect...
by panic
Thu Jan 19, 2023 11:54 am
Forum: Engine Tech
Topic: Gearing Down for Altitude: Dyno Results?
Replies: 10
Views: 412

Re: Gearing Down for Altitude: Dyno Results?

As air density goes down, heat removal by convection is reduced.
Don't lean it out too much.