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#21
11-07-2021, 02:54 PM
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Regarding the specs in post #11 and pastry_chef comment, "Any Comp dealer can get you something that lines up close. Actually any cam company for that matter."
As an example for interest... Comp XE Marine hydraulic roller lobe 3371 for the intake side. On Page 28 here: https://www.compcams.com/lobe-catalog 308 254 171 .3800" lobe lift A little short on the .200" duration and lift, but close. Order it as a 3371B and it will probably come with .3810" lobe lift. Add more rocker ratio if desired. .
__________________
'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 |
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#22
11-07-2021, 03:49 PM
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#23
11-07-2021, 04:07 PM
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#24
11-07-2021, 04:47 PM
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GTO Jones engine built by BES.. 4.75 stroke.. Tony spec'd a 110 LSA cam. Eheads were stated near 360 CFM. Better heads/intake and higher compression, will trend LSA wider. http://forums.maxperformanceinc.com/...d.php?t=788997 Last edited by pastry_chef; 11-07-2021 at 04:53 PM. |
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#25
11-07-2021, 05:27 PM
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Assuming a hydro roller cam and shooting for peak power at 5500 rpm with 489 cid you need 83 degrees of overlap and darn close to a 11 to 1 compression, which should not be a issue with Aluminium heads and at least a intake duration of 250@ ,050”.
__________________
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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#26
11-07-2021, 05:33 PM
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#27
11-07-2021, 10:06 PM
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If you have not bought the rotating assembly yet, get a 4.25.
If you have and have not done the machine work yet run some steel 4 bolt caps, splayed. Running a 4.5 stroke crank with grey iron 2 bolt caps is not wise, foolish. All it takes is a bad load of gas on a hot day and it all could be junk. Its your money and these guys will pick you a fine cam. |
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#28
11-07-2021, 10:15 PM
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.100 -- 71/57 .200 -- 148/130 .300 -- 219/174 .400 -- 272/214 .500 -- 303/221 .600 -- 321/228 .700 -- 325/233 Comp hyd roller lobes ----------------------------- Intake 13459 - 107 centerline 305 253 174 .399 Exhaust 13488 - 111 centerline 313 259 177 .389 Dynomation result ------------------ Full Wave model - HP peak at 5800 RPM. Filling / Emptying model - peak at 6200 RPM. Last edited by pastry_chef; 11-07-2021 at 10:20 PM. |
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#29
11-08-2021, 01:24 AM
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Post 27 should be at least considered. However get on SD Performance website, click on Dave’s header labeled Tech Info, read about the Ram Air exhaust manifolds.
__________________
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... 
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#30
11-08-2021, 10:38 AM
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The lobes pastry_chef brought to the table in post #28 make up the additional .200 duration and lobe lift over the XE Marine lobe I mentioned. They are from the QXI series lobe profiles designed to provide the highest available valve lift for modern cylinder head ports. This pairs well with the OPs proposed 325 cfm cylinders heads that flow well up to .700" lift.
A hydraulic flat tappet cam like the Crower 60245 is rated with only .512" valve lift. Not a good match to take advantage of the proposed cylinder heads. .
__________________
'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 |
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#31
11-08-2021, 10:42 AM
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Quote:
__________________
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...
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#32
11-08-2021, 10:53 AM
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1.65 rocker arms would bring the Crower 60245 up to about 0.563" lift.
Better, look for a hydraulic roller lobe. .
__________________
'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 |
| The Following User Says Thank You to Steve C. For This Useful Post: | ||
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#33
11-08-2021, 01:45 PM
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Thanks. Do not know what method the old Desk top Dyno 2003 uses but I am sure it is not the Full Wave model. 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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#34
11-08-2021, 08:10 PM
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I run a Howards Cams 414455-08 in my 4.5 stoker, nice cam!
__________________
Your car must be very fast ! Because you were haulin ass when I passed you in my GTO. 
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| The Following User Says Thank You to Ozzmann For This Useful Post: | ||
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#35
11-09-2021, 05:53 PM
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Did I miss somewhere what the intended use of this engine is?All street?Some kind of racing?I think the one thing that sticks in my mind that Joe Sheman taughtme was the"better the head the less cam necessary to make a target HP"Tom
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#36
11-09-2021, 07:51 PM
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#37
11-09-2021, 07:53 PM
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#38
11-09-2021, 07:58 PM
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People dont seem to agree on the debate 4 bolt steel main caps or not, with 4.5 stroke. What about the 4.35 stroker crank? When running 4.25 there seem to be no concerns unless the engine is in the 700 hp family. With forged crank the price for 4.35 stroke is the same. Wouldnt more displacement make it easier to make big Power?? Or is 4.25 the absolute max on Pontiacs to run safe 6500-7000 rpm?
Thinking a 4.35 with 0.700 lift solid roller would make a nice engine… |
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#39
11-09-2021, 08:32 PM
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If its all street how much power do you want?Your mostly going to be driving from off idle to 3500?Build it to enjoy driving it and have it last!JMHO,Tom
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#40
11-09-2021, 08:33 PM
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The longer the stroke the more stress you put on the block, stock blocks don't like high stress. With the longer sttoke you don't teally gain power either just more torque.
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