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 2051 matches

by hoffman900
Fri Aug 05, 2022 10:10 am
Forum: Engine Tech
Topic: Longevity of flat plane crank engine?
Replies: 14
Views: 632

Re: Longevity of flat plane crank engine?

The flat plane crank is an advantage on the IMSA engines and how it draws on restrictors. There are performance benefits for sure, especially when you’re chasing those last few percentage points in gains, and not just peak. If the engineering controls are maintained and used within their design cri...
by hoffman900
Thu Aug 04, 2022 11:22 pm
Forum: Engine Tech
Topic: Longevity of flat plane crank engine?
Replies: 14
Views: 632

Re: Longevity of flat plane crank engine?

The flat plane crank is an advantage on the IMSA engines and how it draws on restrictors. There are performance benefits for sure, especially when you’re chasing those last few percentage points in gains, and not just peak. If the engineering controls are maintained and used within their design crit...
by hoffman900
Wed Aug 03, 2022 1:05 pm
Forum: Engine Tech
Topic: is Valovoline VR-1 really hurting engines?
Replies: 23
Views: 1332

Re: is Valovoline VR-1 really hurting engines?

Engine oil is the most reliable and most QA/QC’ed
part of any race engine. 99.9% of the time the issue is not the oil alone.
by hoffman900
Wed Aug 03, 2022 9:42 am
Forum: Engine Tech
Topic: is Valovoline VR-1 really hurting engines?
Replies: 23
Views: 1332

Re: is Valovoline VR-1 really hurting engines?

On facebook about 3 weeks back, someone did a write up of how VR1 absolutely was the cause of an engine failure. I can't for the life of me remember who wrote it, BUT they were a reputable name. Not some internet troll. I've done a couple searches for it, but I cant find the post. That's why I aske...
by hoffman900
Thu Jul 28, 2022 10:12 am
Forum: Engine Tech
Topic: Ever seen 8 rods disintegrate at once?
Replies: 23
Views: 1670

Re: Ever seen 8 rods disintegrate at once?

8 rods going instantaneously, I’d be looking at everything that would effect all cylinders (tune, etc). Sometimes blaming the rod manufacturer is like blaming an electrical fuse manufacturer. Sure it could be the rods, but it could be a lot of other things as well.
by hoffman900
Mon Jul 25, 2022 12:11 pm
Forum: Engine Tech
Topic: Intake closing
Replies: 130
Views: 3738

Re: Intake closing

LSA = (Intake Centerline + Exhaust Centerline)/2 . 100 ICL and 112ECL is 106 LSA as is 104 ICL and 108 ECL, and so would 106 ICL and 106 ECL. Those cams would run completely different. If the valve lift profiles are asymmetrical, they would all be different still. You are describing just one cam, t...
by hoffman900
Mon Jul 25, 2022 9:01 am
Forum: Engine Tech
Topic: Intake closing
Replies: 130
Views: 3738

Re: Intake closing

....What effects the REAL dynamic compression is HOW MUCH air and gas is in the cylinder when the intake valve closes, not at what degree ABDC the valve closes.... UDHarold So considering Harold’s statement above and this from another thread: A volume of air can exist at various pressures, which wi...
by hoffman900
Mon Jul 25, 2022 8:38 am
Forum: Engine Tech
Topic: Intake closing
Replies: 130
Views: 3738

Re: Intake closing

[1] LSA tells you nothing? Hmm. It tells you in crank degrees where each valve is at max lift. Which allows to calculate where the piston is in the bore; and whether that might be the best place for it be for the respective function of the each valve. [2] Even when the LSA is not quoted, it can be ...
by hoffman900
Sun Jul 24, 2022 8:18 pm
Forum: Engine Tech
Topic: Intake closing
Replies: 130
Views: 3738

Re: Intake closing

Fair enough. Although I take little from magazines or cam manufacturers. I have education elsewhere. LSA = (Intake Centerline + Exhaust Centerline)/2 . 100 ICL and 112ECL is 106 LSA as is 104 ICL and 108 ECL, and so would 106 ICL and 106 ECL. Those cams would run completely different. If the valve ...
by hoffman900
Sun Jul 24, 2022 8:08 pm
Forum: Engine Tech
Topic: Intake closing
Replies: 130
Views: 3738

Re: Intake closing

Sticking with a single cam engine, I can't see how LSA is meaningless. I will agree with you that not [sic] "any one event is any more important than the other" but the LSA is most certainly an important element. Having both valves open at the same time...it's proven that all sorts of shit happens ...
by hoffman900
Sun Jul 24, 2022 8:04 pm
Forum: Engine Tech
Topic: Intake closing
Replies: 130
Views: 3738

Re: Intake closing

LSA is pretty meaningless on all engines. LSA tells you nothing. Basically you install it on the prescribed intake center line and LSA is the difference between the ICL and ECL, but short of custom billet cores, most are usually stuck with what is available with cast core sources. But again, the ev...
by hoffman900
Sun Jul 24, 2022 7:47 pm
Forum: Engine Tech
Topic: Intake closing
Replies: 130
Views: 3738

Re: Intake closing

LSA is pretty meaningless on all engines. LSA tells you nothing. Basically you install it on the prescribed intake center line and LSA is the difference between the ICL and ECL, but short of custom billet cores, most are usually stuck with what is available with cast core sources. But again, the eve...
by hoffman900
Fri Jul 22, 2022 2:55 pm
Forum: Engine Tech
Topic: Intake closing
Replies: 130
Views: 3738

Re: Intake closing

On a single camshaft engine, advancing / retarding the cam from installation changes all 4 events. I wouldn’t read too much into these tests. A gain in car performance is a gain. Observing a gain or a loss in * car* performance is important, and informs, either way. "Everything. effects Everything"...
by hoffman900
Fri Jul 22, 2022 1:33 pm
Forum: Engine Tech
Topic: Intake closing
Replies: 130
Views: 3738

Re: Intake closing

On a single camshaft engine, advancing / retarding the cam from installation changes all 4 events. I wouldn’t read too much into these tests.