Thread: 489

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Why would my builder have my compression at 9.7 to 1 motor made 640hp an 590 torque why didn't he make 10.5 to 1 an still run pump gas , I will ask tomarow , motor would have made a lot more power wouldn't it ..I put callies bottom in it an afr heads and 950 quick fuel with a victor jr intake , I can't figure what was on his mind

Don't get too wrapped up in static compression ratio. From 8.0:1 to 9.0:1 is worth a 4% gain. From 9.0:1 to 10.0:1 is worth a 4% gain. From 10.0:1 to 11.0:1 is worth a 4% gain. So, from 9.7:1 to 10.5:1 is worth about a 3% gain, or about 640 times 0.03 or about 20 horsepower. However, that little bit of extra power might come at the expense of a more radical cam to keep up with the cylinder pressure and prevent detonation. That bigger cam may have moved the effective cam operating range out of the comfort range that he had planned for you and the motor may have been less effective at what the main plan was. It could very well have made the car slower, depending on cam operating range.

Bottom line, ask him, but that would be my take on it. You fellows don't always have to run the range all the way up against the wall. That's one of my pet peeves with fuel pressure in carburetors. Why in heaven's name do you want to run the fuel pressure right up against the wall when you know that there's no advantage, only downside?

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How many pulls did he make and what changes did he do between pulls?????? Change cam timing? Ign curve? Headers? carbs or jetting?? Intake manifolds??

He made timing changes it is at 40 degrees, and jetting are 83 front and 94 back , made 5 pulls on it he got a great name on builds all he ever done , my buddy got one like mind at 10.8 to 1 an he dynoed at wheels 620 hp , an I have Howard's cam 640 lift. Diffent guy done my buddy's build he got same lift cam but is a lunati

Also my buddy's 489 was built by another builder

I bought Doug headers and finally after 3 hrs got the motor in an headers hit steering column cyl.. 3 5 7 when I turn steering wheel raise motor up an dn , don't no what to do

Cut the header and rearrange it to clear.

Not hard, just time consuming.

Got my car out today an drove it,that thing is a hoss.but when I turn headlights on the tach an heat gauge an amp hand quits working an can tell motor wants to struggle dn low idle ?..

Also he put a big big fuel pump on it electic it is very loud , could It be taking all of juice to run it an whe turn lights on makes stuff short out

a short would blow a fuse, maybe your alternator isn't up to the task, drive it by orielly and seen if they can load test it. if it's the original alternator and now you added a bunch of accessories (EX. Cd ignition, electric fans, fuel pump etc) it's just not giving enough amps, also the alt feed wire must be upgraded to supply more amps as well, powermaster says it's kind of like drinking a thick milkshake through a coffee stirrer, bigger alternator means bigger supply wiring. as far as a big big loud electric fuel pump, good luck even the so called quiet inline pumps are noisy, trust me on this I have tried the holley rotor style, the edelbrock quiet vane type and just about all are noisy, some are better but none are a walbro Efi in tank pump, which by the way is quiet. good luck there, oh yeah I have isolated them in every imaginable insulator too!

Look to see how the fuel pump was installed... If it's loud I would expect it is not an in- tank pump. It probably needs rubber isolators.
Why electric? Mechanical are quieter, more reliable, and produce a non- linear flow rate (what the engine needs)
The struggling idle may be un- related to the electrical issue, unless it only happens when lights are on.
Modern halogens pull more power comparedly.
A bigger alternator might solve your problems, but if you upgrade, then I would consider a heavier guage wire to the main junction.

I have got blow by coming out of driver side oil cap an it is a little milky I think motor is sweating. Why would it have blow by were its new , don't have about 100 miles on it , today runner her pretty hard an it blowed water out the oil cap all way to fender , oil is not milky after run it an get hot

Can you say head gasket or cracked head

Could be getting rid of water but don't come out tail pipes an not a lot of water in oil , could it be going aroun head bolts not seated yet. He set ring gap a little wider so I can run nitrous if I want an it just has the blow by coming out of driver side cap , passenger side has cap on it but no blow by

head studs?????? use sealer on threads into block???? they'll leak up the shaft of the stud thru the bolt tunnel in the head and then thru the threads of the stud/nuts and be a pretty good trickle of fluid-multiply it by the number of fasteners and it gets nasty in a hurry---------