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 1812 matches

by RevTheory
Thu Nov 26, 2020 9:49 am
Forum: Engine Tech
Topic: Big Issues with Cylinder Pressure (DCR)
Replies: 84
Views: 2162

Re: Big Issues with Cylinder Pressure (DCR)

Thanks, a big reason i don't rely on DCR as a thing is because it doesnt give me the information i need. ...both cams are the same size, only difference is intake centerline. Could you load the 632 on pump gas? why did the 632 make almost 300 more hp granted the dynamic compression ratio is junk? I...
by RevTheory
Fri Nov 20, 2020 2:09 pm
Forum: Engine Tech
Topic: Small cams on 106-108 LSA’s
Replies: 47
Views: 2145

Re: Small cams on 106-108 LSA’s

I believe the rest of the combo needs to be taken into account when discussing LSA. Tight LSA cams generally work with FREELY flowing exhaust systems. A restrictive exhaust KILLS a cam with overlap. Small cams are often used with stock exhaust manifolds and small exhaust systems. Overlap is bad wit...
by RevTheory
Thu Nov 19, 2020 9:57 am
Forum: Engine Tech
Topic: Small cams on 106-108 LSA’s
Replies: 47
Views: 2145

Re: Small cams on 106-108 LSA’s

I had a Howard's hyd/flat cam ground a while back that was 259/259 at .006, 212/212 at .050 and .519/.519 lift on a 108 +4 for a 9.75:1 AMC 360 and you could tell it had a little something in there but the damn thing pulled 19 inches of vacuum and the guy said it pulled like a train just off idle up...
by RevTheory
Wed Nov 11, 2020 10:47 am
Forum: Engine Tech
Topic: Rev kits , hydraulic roller cams.
Replies: 12
Views: 525

Re: Rev kits , hydraulic roller cams.

Mike, if a lobe profile is designed so aggressive on and off the seat that it upsets the plunger, a rev kit won't fix that, correct?
by RevTheory
Tue Nov 10, 2020 12:59 pm
Forum: Engine Tech
Topic: Rev kits , hydraulic roller cams.
Replies: 12
Views: 525

Re: Rev kits , hydraulic roller cams.

CamKing wrote: Tue Nov 10, 2020 12:27 pm One thing to remember. All those "Limited Travel" hydr roller lifters you see, aren't really hydraulic. They're designed to bottom-out, and run as a mechanical lifter.
So if that's the lifter you plan on running, should you look at solid profiles rather than hydraulics?
by RevTheory
Sun Nov 08, 2020 6:34 pm
Forum: Engine Tech
Topic: Comparing Apples To Oranges! (Cams)
Replies: 21
Views: 789

Re: Comparing Apples To Oranges! (Cams)

I'm the king of not getting questions answered and have simply stopped asking so I get it. Having said that, only maybe a couple of guys are going to know the real story between those two cams. We don't know the symmetry or duration at .200 or how well either one rolls over the nose or what. One thi...
by RevTheory
Sun Nov 08, 2020 4:15 pm
Forum: Engine Tech
Topic: Comparing Apples To Oranges! (Cams)
Replies: 21
Views: 789

Re: Comparing Apples To Oranges! (Cams)

Yep. Probably not much difference.
by RevTheory
Sun Nov 08, 2020 1:45 pm
Forum: Engine Tech
Topic: Comparing Apples To Oranges! (Cams)
Replies: 21
Views: 789

Re: Comparing Apples To Oranges! (Cams)

i'd just skip it, and find a cam with lobes designed this century. cost difference between an antique grind, and a quality modern grind is insignifigant vs the benefits IMO. Yeah, I should just skip the whole car then and buy a car from this century then....... Don't take offense. He has a valid po...
by RevTheory
Fri Nov 06, 2020 7:42 pm
Forum: Engine Tech
Topic: Weak part throttle performance
Replies: 41
Views: 1178

Re: Weak part throttle performance

If you think in terms of air density, it'll make sense. You can't just move the hose from one port to the other, though; it needs to be dialed in and the centrifugal needs to be on point.
by RevTheory
Fri Nov 06, 2020 10:38 am
Forum: Engine Tech
Topic: Summit’s pro sbc camshafts ?
Replies: 11
Views: 910

Re: Summit’s pro sbc camshafts ?

Mike, is that why when you send someone to say Lunati or Howard's with a specific custom grind, the guy on the phone nearly always pushes them off to a shelf grind? Basically because they didn't grind it in the first place and their profit margin is higher?
by RevTheory
Tue Nov 03, 2020 3:45 pm
Forum: Engine Tech
Topic: Budget 350 RV build
Replies: 16
Views: 614

Re: Budget 350 RV build

Can you at least talk him into some iron Vortecs? They're probably ~$500 or so a pair from Scummit or Jegs.
by RevTheory
Sun Nov 01, 2020 8:02 am
Forum: Engine Tech
Topic: Y-pipe design effect on exhaust sound
Replies: 13
Views: 530

Re: Y-pipe design effect on exhaust sound

Interesting thread. I've always wondered what made factory LS engines sound like a V6 under water, lol.
by RevTheory
Wed Oct 21, 2020 10:47 am
Forum: David Vizard forum
Topic: EQ – all-time best BBC iron heads?
Replies: 23
Views: 1368

Re: EQ – all-time best BBC iron heads?

I haven't been teased this much since high school, lol
by RevTheory
Sun Oct 18, 2020 8:19 am
Forum: Engine Tech
Topic: power valve circuit myths
Replies: 39
Views: 2191

Re: power valve circuit myths

If the diaphragm isn't ruptured and fuel isn't being drawn from the boosters, where does the excess fuel come from then?
by RevTheory
Wed Oct 14, 2020 10:42 am
Forum: Engine Tech
Topic: power valve circuit myths
Replies: 39
Views: 2191

Re: power valve circuit myths

If the power valve opens at 8.5 and he's idling at 6, the valve will sit there open but not flowing until there's enough depression to draw from the boosters, correct?