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#81
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The package that is for sell does not include Pontiac. It only does SBC, SBF, and for BBC only HRT. Yes, I know I posted an output for Pontiac. But the Pontiac option is experimental and less than 6 people in the world have a version of the software where the Pontiac option works. Stan
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Stan Weiss/World Wide Enterprises Offering Performance Software Since 1987 http://www.magneticlynx.com/carfor/carfor.htm David Vizard & Stan Weiss' IOP / Flow / Induction Optimization - Cam Selection Software http://www.magneticlynx.com/DV Download FREE 14 Trial IOP / Flow Software http://www.magneticlynx.com/DV/Flow_..._Day_Trial.php Pontiac Pump Gas List http://www.magneticlynx.com/carfor/pont_gas.htm Using PMD Block and Heads List http://www.magneticlynx.com/carfor/pont_pmd.htm |
#82
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"The Mustang's front end is problematic... get yourself a Firebird." - Red Forman |
#83
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#84
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Stan
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Stan Weiss/World Wide Enterprises Offering Performance Software Since 1987 http://www.magneticlynx.com/carfor/carfor.htm David Vizard & Stan Weiss' IOP / Flow / Induction Optimization - Cam Selection Software http://www.magneticlynx.com/DV Download FREE 14 Trial IOP / Flow Software http://www.magneticlynx.com/DV/Flow_..._Day_Trial.php Pontiac Pump Gas List http://www.magneticlynx.com/carfor/pont_gas.htm Using PMD Block and Heads List http://www.magneticlynx.com/carfor/pont_pmd.htm |
#85
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My concern is 9.0 compression, power steering, power brakes, air-conditioning auto trans and I need to have good vacuum a strong steady idle and it has to be reliable to to take on trips. And the fact that it has RA/HO exhaust manifolds and full exhaust. Doesn't less duration build dynamic compression.
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Tim Corcoran |
#86
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#87
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Stan
I looked at your analysis you included and it has vacuum at 11.2 hg. I would not be happy at all if with that little vacuum that would be a very weak idle turning all my accessories.
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Tim Corcoran |
#88
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I am willing to go with a little more duration just concerned about vacuum and idle quality since I only have 9.0:1 static compression auto trans, PS, AC and restricted exhaust. I am not after max power but do want to take advantage of the airflow of the heads. I am considering the cam that Lemans 400 suggested (282/288 adv 230/236 @.050 .510/.521 lift) Butler had it custom ground from the 112 to 114 LSA. How much vacuum do you think I would have at idle with that cam and how radical of an idle would you expect?
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Tim Corcoran |
#89
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What is the min vacuum you want? Stan
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Stan Weiss/World Wide Enterprises Offering Performance Software Since 1987 http://www.magneticlynx.com/carfor/carfor.htm David Vizard & Stan Weiss' IOP / Flow / Induction Optimization - Cam Selection Software http://www.magneticlynx.com/DV Download FREE 14 Trial IOP / Flow Software http://www.magneticlynx.com/DV/Flow_..._Day_Trial.php Pontiac Pump Gas List http://www.magneticlynx.com/carfor/pont_gas.htm Using PMD Block and Heads List http://www.magneticlynx.com/carfor/pont_pmd.htm |
#90
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The 428 in my '66 GTO has a custom cam with cam card attached below, 114 LSA installed at 110 ICL. I have 1.5:1 rockers. Crane made it for me back in 1996 or so. According to 1/4 mile MPH and ET calculators, it makes in the neighborhood of 550HP. And loves to rev. This engine has 72cc E-heads, Doug's headers, and EFI. CR is 11.4:1 and works fine with 91 octane. (with this cam, might be too much with less cam) As well as this cam performs, it's too much for the street and I'd like to take it down a notch or two. Exhaust stinks with the modern fuel we have now, probably because the exhaust valves open so soon. Last edited by hgerhardt; 06-30-2022 at 01:52 AM. |
#91
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On a 9:1 4” stroke engine I think you would find all the Bulter 230, 236 HR in the 114 version is going to offer versus the 112 version is to make less power, get worse economy, and not change the vacuum or idle very much. Just my 2 cent. 112 would be better, the next size smaller 224, 230 would be ok on 114 if you really after something mild.
I am not crazy about extra lift on the exhaust side of those Bulter cams, I think it hurts more than it helps, and is really no benefit, it is just beating up your valve guides more, even more so with 1.65s. Would be nice to know the heads flow at different lifts. That has potential to effect the LSA you might want quite a bit also, which is just a guess right now. Big low lift flows tend to make the cam act like the LSA is narrower. Changing a 6x head to 45* intakes from 30* do the opposite, making the cam LSA act wider. Some people manipulate that port flow at low lifts a lot when they port the heads, and don’t really even realize it. That can change the compression your engine can pump before it pings, and the E/I split you might want on your cam. Slowbird 274 XE example is probably a good example of pumping more compression. I think he had 45* valves on that engine judging by how much compression he had on his XE 274 engine. Just my hunch anyway. Sometimes cams will respond better to a smallish aggresive cam when the low lifts are not as high. 45* intake valves generally do that. If vacuum is a concern, that 30*s have less vacuum too. Be nice to know that stuff if you want the get the best cam narrowed down. Last edited by Jay S; 06-30-2022 at 02:29 AM. |
#92
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hgerhardt
Your Edelbrock heads flow well past 0.600" valve lift. Your current net valve lift after the indicated .020" valve lash is 0.610". This is a very good match. If you change from your current cam to the XFI hyd roller lobe 3017 you will be giving up some valuable valve lift. From the 0.610" to 0.579". Rather than a XFI lobe you might consider Comp QXI lobe 13451 on page 24 here: https://www.compcams.com/lobe-catalog It is rated with 0.593" valve lift and it has a similar 0.200" duration as the XFI lobe. .
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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 ) Old information here: http://www.hotrod.com/articles/0712p...tiac-trans-am/ Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine) 5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension https://www.youtube.com/watch?v=qDoJnIP3HgE |
#93
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The Following User Says Thank You to slowbird For This Useful Post: | ||
#94
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hgerhardt, you eluded to a good point in your post...
"CR is 11.4:1 and works fine with 91 octane. (with this cam, might be too much with less cam)" Your solid roller cam is rated at 0.0205" tappet lift whereas the Comp hydraulic roller cam is rated at 0.006" tappet lift. Therefore the 'advertised' duration for the two cams will not be apples-to-apples. Here is a conversation that considers the situation: https://www.forbbodiesonly.com/mopar...arison.205262/ The information provided in that specific thread does not represent any endorsement. It is offered for general interest only. I personally don't know enough about that specific topic, I suspect Jay S would. Maybe he will chime in. .
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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 ) Old information here: http://www.hotrod.com/articles/0712p...tiac-trans-am/ Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine) 5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension https://www.youtube.com/watch?v=qDoJnIP3HgE Last edited by Steve C.; 06-30-2022 at 09:29 AM. |
#95
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But differences in duration at ~0.010 lift are not obvious to me and I am surprised if differences in duration below 0.010" cause big differences in performance. I can see that the 068 will have longer duration at maybe 0.006" but does that really have a big effect? All this must be really sensitive! |
#96
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Stan
__________________
Stan Weiss/World Wide Enterprises Offering Performance Software Since 1987 http://www.magneticlynx.com/carfor/carfor.htm David Vizard & Stan Weiss' IOP / Flow / Induction Optimization - Cam Selection Software http://www.magneticlynx.com/DV Download FREE 14 Trial IOP / Flow Software http://www.magneticlynx.com/DV/Flow_..._Day_Trial.php Pontiac Pump Gas List http://www.magneticlynx.com/carfor/pont_gas.htm Using PMD Block and Heads List http://www.magneticlynx.com/carfor/pont_pmd.htm |
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