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#21
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What cam are you currently running in your 455 combo? Thanks
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71 GTO, 463, KRE 295 cfm heads ported by SD Performance, RPM intake, Qjet, Dougs Headers, Comp cams HR 246/252 ...11 to 1 , 3.55 cogs, 3985lbs.....day three- 11.04 at 120mph ....1.53 60', 6.98 1/8 mile |
#22
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60919 is a bad cam for a street only car. I had one in a 462 it was lumpy with no bottom end. The 389 I took out of the car had more bottom end.
Jim Hand nailed it, use either the 068 or the Summit 2801 with 9 to 1 compression. That way you'll have smooth idling, vacuum for power brakes, brute off idle torque, and you can run a nice 3:08 or higher rear end. Quit trying to build a drag racing car for the street.. It doesn't work. Street is a whole different thing, much more complicated.. Look up Jim Hand and Nunzi.. Change that rear end to a 3:08 and get a 13" converter in there for torque multiplication.. On the street the stator is the ticket.. Last edited by 389; 08-06-2019 at 03:42 PM. |
#23
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#24
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David Vizard routinely builds motors with 190 psi of cranking pressure and runs them on 93 octane fuel without issue, this is with Aluminum heads used , not iron.
He also clearly states that for every 1 point loss in fuel octane from a 93 rated fuel used he needs to drop 5 psi of cranking pressure out of the cylinders to not have a issue. In light of this info I would have to say without question that a motor showing only 160 psi of hot cranking cylinder pressure should have no issue running without knock or ping on 93 octane fuel if the tune is right , the Intake air temps and coolant temps are within reason and the Cam of course is in right!
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Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
#25
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Cliff, What cam are you currently running in your 455 combo?
The current engine uses SD's "Old Faithful" cam with 1.65 rockers on it. It's on a 112 LSA with the ICL at 109.5. Idles nearly dead smooth with 13.5 vacuum at 750rpms. Excellent street manners. My first 455 had 6X-4 iron heads and Crower 60919 cam, Rhoads lifters and high ratio rockers on it. It made great power and excellent street manners as well, 12" vacuum at 700-750 rpm's, strong off idle power and ran as quick as 12.0's at 112MPH at the track. Later on I added KRE heads for the KRE dyno head testing that made HPP and Popular Hot Roddings "Engine Masters" articles. A few years later I did some cam testing and replaced the Crower 60919 with a custom ground hydraulic roller cam with 230/242/112 specs. It was worth 3hp/4ft lbs torque for the $1000 investment. It does show us that you can mimic the power of a well chosen roller cam with a flat cam using Rhoads lifters and high ratio rocker arms. I did run a bit quicker at the track with the HR cam, best ever with the flat cam was 11.64. I went 11.52 with the HR cam and almost 2mph faster........Cliff
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If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
#26
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[QUOTE=389;6048543]60919 is a bad cam for a street only car. I had one in a 462 it was lumpy with no bottom end. The 389 I took out of the car had more bottom end.
Quit trying to build a drag racing car for the street.. It doesn't work. Street is a whole different thing, much more complicated.. Look up Jim Hand and Nunzi.. The OP'er of thread IS trying to get away from the 1/4 mile combination that his car came with. His direction may be dictated by a budget (like mine would be...). His beginning may have not exactly hit the mark, as can happen...I, also vote for a set of 6X-8 heads, with the 2802 cam... Jim Hand ran the 041 cam for a long time in his wagon engine 455. Lots of experimentation. he drag raced the wagon to get performance comparisons. His main goal was to get the best performance with the best drive-ability. He uses Rhoads lifters for better idle and a slight bump in low end power. He always steers towards an all around good driving well mannered street driven vehicle. Having said all this, I know the 041 Jim used the 041 for quite a while (the 041 and 60919 are VERY close in specs). Jim's engine(s) are very finely detailed in all areas. It's likely that his success with the 041 cam may not be easily duplicated by others. Te latest cam that Jim has been using is the Wolverine 5059 (no long being manufactured), it has a few degrees duration. It also has good driving characteristics for street driving... I too, remember Jim mentioning about how much he liked the 068 cam. I believe it was in more of a mild combination than his 6X headed versions. I believe the 068 cam was used with 96 heads, and I believe 1.65 rockers. He also experimented with cam timing quite a bit with that combo (he may have played with cam timing with all his engines...) I don't know what to think about using the round port heads on a specific "driver" 455. It wouldn't be a head choice I would pursue. I bought a 041 cam here, for a good price. Hope to use it in a 455 build. Especially hope to nail down all the finer details to mimic Jim's 455 build. Zero decking, port work, no sharp edges in chamber or on piston, proper cam timing (109 ICL), hone with torque plate, proper carb tuning, proper dist setup, and I plan to use a 72 iron intake...I am sure I left out some stuff.... My only thought for current combo is checking the ICL. I have read here about timing gears being mis-marked on occasion. So much of the stuff is imported, quality control is not a big deal to the makers. THey collect their 25 cents a day and go home.
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1977 Black Trans Am 180 HP Auto, essentially base model T/A. I'm the original owner, purchased May 7, 1977. Shut it off Shut it off Buddy, I just shut your Prius down... Last edited by 77 TRASHCAN; 08-07-2019 at 08:53 AM. |
#27
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I run a set of 72s on my 400 with a mild cam and it's a blast to drive on the street. No one can catch me so far. They all catch up at the next light and just shake their heads and say they couldn't keep up. Sooo much fun beating those turbo diesel trucks that think they are all that. They are quick but no match for a real hotrod. By the time I hit third I'm passing them and they are leaning forward in their seat like they can somehow go faster like that. I just love chirping the tires in the power band while I hit third gear as I'm passing them. I do use octane booster, one bottle a tank, just for piece of mind that my high compression 400 isn't silently destroying itself. No detonation specs on the plugs. |
#28
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Thanks for that info...still having a tough time stomaching the extra expense vs gain myself. Do you know anyone running the road paver grind? Wondering if I do choose to go roller if I should look stepping it up a notch. Or simply stay with what I’m using. A couple more questions if I may: What forged cranks are being used/recommended these days? Would you even consider building a 3.25 main engine if starting from scratch? Considering the stroker kits available etc. Sorry for the bother but appreciate any input....thanks
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71 GTO, 463, KRE 295 cfm heads ported by SD Performance, RPM intake, Qjet, Dougs Headers, Comp cams HR 246/252 ...11 to 1 , 3.55 cogs, 3985lbs.....day three- 11.04 at 120mph ....1.53 60', 6.98 1/8 mile |
#29
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didnt you say awhile back in the "ticking" threads that you have to use 2 bottles of octane booster in every tank because of the detonation that small cam you have causes? isn't that considered a "quick fix"? |
#30
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First, the ticking was the new junk lifters Lunati sold me. The 703 cam might have been junk also. Sent them both back. Good riddance. The cam was in there long enough for some test drives. Wasn't impressed. Moved the power up over 4000 rpm which isn't what I like. IMO stupid choice for a strictly street driver. It was highly recced here. Glad I tried it out (I guess). At least I can speak about it from experience. I used the Edelbrock 2157 cam and it works perfectly for my combo on the street. I use 93 and one bottle of 108 octane booster a tank. I got a deal on a case of the 108 from Advance Online for $3 a bottle. What I have is a fine example of a fun street car anyone would thoroughly enjoy driving. A true success story. Anyway, my point was that the aluminum round port heads are better than the 6x you voted for. I have had many engines with the 6X heads and this one with the round ports. IMO the round ports are much better. Last edited by TAQuest; 08-07-2019 at 09:54 AM. |
#31
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Do you know anyone running the road paver grind?
We use the RP in a 455 with ported #62's. It idles about as good as the 455 in my car, which to this day amazes me. Good street manners as well. I quit doing these engines couple of years ago, but at that time the 3" main forged cranks were plentiful. Pretty much a waste of time/funds to overpay for a 428 or 455 block and use a factory crank, IMHO. This assumes the good forged cranks are still out there. I've had perfect success with them, most were from Star Galaxy. I do send all my rotating assemblies out to be balanced and cranks/rods checked, etc. The early cast steel cranks weren't that great, and to this day I avoid all of them. The forgings have been fine, we even have one in a 505 making nearly 750hp and it's been living just fine now close to 15 years with one set of rod bearings rolled in it.......Cliff
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If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
#32
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sounds like the same issue going on here, as cliff & others have said, the cam is WAY too small for the engine combo & is whats causing the detonation. |
#33
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So you can't blame the ping on my cam choice. I know you love to do that but it's not true. It's the compression, not the cam. The 703 install was enough to prove it. The 400 came with the 72cc round ports when I bought it so it's high compression. Much like a 455 with the higher cc round ports like the guy here asking for help. No way in heck I would switch those heads for 6x heads like you advised. That would be a mistake in my opinion. You can keep circling around that point if you like. I would like to help the guy who started the thread if I may. |
#34
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I would install two bungs and wide band O2 sensors and check the A/F ratio before I did anything else. The solution to your problem could be a simple change to the carburetor. If it still knocks after getting the A/F ratio right, you could richen it up (add fuel) a little and see if that eliminates knock but using fuel as an anti-detonant is not good practice.
There are tools available which makes tuning a motor correctly simple and easy https://www.summitracing.com/parts/inn-3891?rrec=true |
#35
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#36
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i also never advised the OP or anyone to swap to 6x heads, not sure where you got that from... however, swapping to 6x heads for a engine that has too much compression due to the e-heads & runs a very small cam with no need for max power or drag racing etc is a legitimate suggestion. with small cams like these, the e-heads are a waste & you gain nothing on the street compared to a good set of iron heads... especially if they will lower the compression & be a better match for the small cam. |
#37
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I am the expert grasshopper. Learn from what I experience. Keep quiet unless you have real things to say. Listen to real world experience when you have someone who actually possesses the hardware. |
#38
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Why not just slow down the timing curve to come all-in by 3000-3500 and not 2500? See what that does. I thought the modern chambers and high compression don't need a quick curve?
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I could explain all this to the girl at the parts store, but she'd probably call the asylum. White '67 LeMans 407/TH350/Ford 3.89... RIP Red '67 LeMans. 407/TH400/Ford 3.25 |
#39
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Cliff, Thanks .....appreciate your comments Snapped my N crank in half recently and looking to shore up some areas ...
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71 GTO, 463, KRE 295 cfm heads ported by SD Performance, RPM intake, Qjet, Dougs Headers, Comp cams HR 246/252 ...11 to 1 , 3.55 cogs, 3985lbs.....day three- 11.04 at 120mph ....1.53 60', 6.98 1/8 mile |
#40
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my comments are not guesses or on paper, they are factual statements based on what others are saying here & have said to you countless times in the past... but for some reason that triggers you & you repeat this same nonsense, then you start insulting people trying to help & call them childish names & can't keep track of who posted what info... talk about flapping your keys! for some unknown reason you cant seem to grasp the concept of using too small of a cam for a high compression engine, or using e-heads with a small RV cam that has all of .420 lift & 204 duration. so you are correct, i would never have the combo you have with a 2157 cam on a ~11:1 400 & claim it "runs great"! you are the expert? learn from what you experience?? LOL!!! your previous threads & comments about problems with the 2157 cam show your level of real world experience & knowledge, you picked too small of a cam for your combo & can't get it running right... unless you consider running right with your "quick fix" needing to run octane booster & retard the timing so the engine doesnt ping! yet you feel qualified to give "advice" on detonation?! ok. |
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