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#1
03-12-2014, 09:38 PM
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Too much cam ?
Just had my 455 bored out to 470, refreshed, with new rings ,main ,rod and cam bearings. presently has a crower 60244 cam. J&E dome pistons , compression at about 9.8 to 1 heads are 6-X8 101cc's ported by Kaufman to flow 279 cfm int and 240 cfm ex. Good to .600 lift , screw in studs.Harland sharp 1.65 roller rockers, new Roads lifters to be installed, Torker intake, demon carb , hooker headers, 2.5 in exhaust with cross over. 4sp with stock 3.90 gear ratio, manual brakes. 68 GTO, rag top.I don't race the car but I like to take it out at let er have it when i can . I love my low end torque , is this cam too much for my use . will my low end torque suffer very much. Any and all opinions and thoughts welcome . thks
Last edited by gennaro; 03-12-2014 at 09:47 PM. |
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#2
03-13-2014, 12:45 AM
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I'm no expert, as they will chime in, but a quick search states a compression ratio of atleast 11 to 1 for that cam. You said you have 9.8 to 1. Thats an immediate red flag to me.
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1970 lemans sport. 464, ported 6X-8 heads, 1.77 EX valve, 3 angle valve job, H.S. 1.65 roller rockers, XE284, RPM intake, H beams, forged speed pro's, eagle ESP crank, Full ARP studded, Billet 4 bolt mains. |
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#3
03-13-2014, 01:07 AM
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If you have a wide ratio 4 sp with that 3:90 I think you will still have plenty of street grunt. That said, 2 1/2" exhaust for 470 inches, you're leaving a bunch on the table there.
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68 Cat 2 dr sedan 461ci 670 heads XE284H 850 Holley 493/525 wide ratio 4sp 3:42 posi 13.07@105 full exhaust |
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#4
03-13-2014, 02:38 AM
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Not trying to hijack a thread, but elaborate on "leaving a bunch on the table" as far as only using 2 1/2" exhaust as i have a 464 with the same. We talking 5hp or 25hp?
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1970 lemans sport. 464, ported 6X-8 heads, 1.77 EX valve, 3 angle valve job, H.S. 1.65 roller rockers, XE284, RPM intake, H beams, forged speed pro's, eagle ESP crank, Full ARP studded, Billet 4 bolt mains. |
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#5
03-13-2014, 06:41 AM
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Cam looks fine for what you are doing. Hopefully you used the Torker II intake, not the original Torker.
+2 on the 2.5" exhaust. An engine that big needs 3" head pipes, and you leave a lot of power on the table not using them, especially with heads that have received the porting that yours have....IMHO......Cliff
__________________
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), |
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#6
03-13-2014, 07:09 AM
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Are those Exhaust flow numbers from Kaufman the bare port, or flow numbers thru a tube?
__________________
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! |
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#7
03-13-2014, 07:32 AM
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I have this sheet from Kaufman , that came with theses heads , the heads were off the engine that i bought . I m no expert on this stuff, the compression ratio concerns me . I did some calculations using the Wallace web site , but not sure if i did it right. I did have the engine in the car for a short time , with regular lifters before i pulled it out for a refresh, seemd to run good, just wondering if a lesser cam would do better.
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#8
03-13-2014, 12:19 PM
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What are the concerns about the compression ratio?.....Cliff
__________________
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), |
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#9
03-13-2014, 12:30 PM
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Just concered that it may be to high, i would like a pump gas, streetable engine with out loosing to much power. How would the 60244 Crower effect compression? and how can i determine what the accurate copression ratio is with this set up?
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#10
03-13-2014, 12:44 PM
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Whatever you decide, make sure you degree it. Mine took the +8 key.
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 68 Firebird, trying a q-jet now. 434/10.5:1/997's/240-242 HFT/4L80E/2800 Yank/3.42's/ Vintage Air/ 13.0 @105 mph 70 Lemans, 350/350, A/C, mostly stock 14 Ram CC, 5.7 Hemi, 8-speed, 3.92 lsd 97 Trans Am, HPP Aug 2012 http://www.highperformancepontiac.co...tiac_trans_am/ ***Sold*** |
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#11
03-13-2014, 10:10 PM
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The compression ratio with 101cc heads isn't too high, if anything a tad low. That much cam with high ratio rockers will idle with pretty low vacuum, probably about 10-12" or so, plenty for power brakes, but it is certainly a candidate for Rhoad's lifters...IMHO....Cliff
__________________
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), |
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#12
03-13-2014, 10:22 PM
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As stated on a previous thread by Scott-462 , he came up with 11-1 compression ratio, not quite understanding how he arrived at that , is that static?, and what would the dynamic be.?
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#13
03-14-2014, 12:55 AM
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How i came up with that is thats what several websites said the cam manufacturer recommends the engine to have to run this cam... I wasnt saying you had that much.
__________________
1970 lemans sport. 464, ported 6X-8 heads, 1.77 EX valve, 3 angle valve job, H.S. 1.65 roller rockers, XE284, RPM intake, H beams, forged speed pro's, eagle ESP crank, Full ARP studded, Billet 4 bolt mains. Last edited by scott-462; 03-14-2014 at 01:16 AM. |
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#14
03-14-2014, 06:23 AM
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The cam manufacturers do NOT know what size engine you are putting their cam in. In a 400 engine it would REQUIRE at least 11 to 1 compression, unless you don't care about idle quality, sluggish off idle, and no real power till past 3000rpm's or so.
In a 455 it is a very good candidate for around 10 to 1 compression, but I would install Rhoad's V-max lifters on it in combination with the 1.65 rocker arms. I've never used that cam specifically, but it is close to the 60919 cam in advertised numbers, and not too far off the no longer available Wolverine 5059 cam. Both of those cams had over 300 degrees seat timing on both lobes, wide LSA, and work best in 455 builds with at least 10 to 1 compression.....Cliff
__________________
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), |
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#15
03-14-2014, 06:56 AM
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My mistake Scott-462 , I Interpreted your post wrong.
Want to thank everybody for their input , now i have to figure out how to Degree this cam.I have my engine on a stand with heads off and the cam straight up on the marks.I've never done this and have to purchase what ever tools i need so any recommendations for far a novice would be appreciated . |
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#16
03-14-2014, 08:54 AM
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As much as I like and have used the Crower cams, for some reason non of them to date have been close "dot to dot" on a timing set. In most cases it has taken 4 to 6 degrees advance to get them where they need to be......Cliff
__________________
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), |
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#17
03-14-2014, 10:43 PM
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You mention that you have JE dome pistons. What size/cc dome is it? The size of them will effect CR a great deal.
__________________
'67 GTO 400 HO - Ram Air - 4 speed - 3.55 Safe T Track, A/C, PS, red fender liners '78 Lemans - Drag car project |
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