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  #46 (permalink)  
Old 07-15-2012, 12:28 PM
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spacer

You wont need a spacer for a Vic Jr manifold.I only use a 3.50 gear. The tremec has I believe 2.78 1st gear.That gives me close to 10:1 first gear over all ratio with a 27 inch street tire it does 54 ish mph in first.just over 2k at 60 mph.I use a solid roller and it buzzes flawlessly over 7k.I put a 6k chip in the rev limiter now as I have too much power to traction ratio atm.
You will have the same problem with the better manifold.If you used a 4.1 rear gear that would give you 11.4 :1 over all first gear. What over all first gear do you think is best?

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  #47 (permalink)  
Old 07-15-2012, 09:01 PM
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horsepower stumped

Its a stepin the right direction with a 4:33 rea end and a.68 overdrive I'll have a 2.93 final drive which is where I want to be on the highway with a 4:56 I'll have a 3.10 final drive again thats fine.
does anyone run dynomax ultraflo welded mufflers and if so how do they perform and sound, Thank you again everyone you have all been a great help
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  #48 (permalink)  
Old 07-17-2012, 06:39 PM
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horsepower stumped

Well i hace freed up the cats and installed 3 inch maganaflow 4inch round bullets HOLY CRAP F Bird you were so right the machine breaths abd does not run out of breath, last night I put her through her pace and she kept pulling and pulling I took her to 7000 rpm with no hesitation although I know I have to keep her no more than 6500 rpm cant wait to put in the 5 speed with 4.10's i'll keep you posted, oh yeah if like flow and loud go wiyh bullets
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  #49 (permalink)  
Old 07-17-2012, 06:52 PM
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Magnaflow has other really good mufflers besides race bullets.
Not the best choice for the street. Just a bit loud to get past a cop. They sell hi flow cats too.
"Carsound"
The Official Site of MagnaFlow Exhaust Products - Exhaust Systems For Trucks, Suv's, American Muscle, Diesel, & Sport Compact Vehicles.

If you want to rev it up that high you should be using a solid roller cam.
Hyd rollers get unstable somewhere between 6500-7000.
Unless you employ really good springs and lots of spring pressure.
Best to keep it under 7000.
Many people that want to buzz a hyd roller up that high use the
AFR hydra rev rev kit.

A t least now you know the effect of exhaust system restriction on a high perf engine.

Now you need some traction. Your new tires are waiting for you to pick 'em up.
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  #50 (permalink)  
Old 07-20-2012, 11:16 AM
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Just a note,

Howards Cams also has a rev kit for Hydraulic Rollers.
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Old 07-23-2012, 06:29 AM
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F-Bird how can I contact you to pick up the tires are they the M&H racemaster 275/60/15 my number is 905-839-9511 hm
416-729-4766 cell
e-mail gsapounakis@hotmail.com I'm in Pickering Whites rd and Finch
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  #52 (permalink)  
Old 07-23-2012, 01:49 PM
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Quote:
Originally Posted by sapsz28 View Post
F-Bird how can I contact you to pick up the tires are they the M&H racemaster 275/60/15 my number is 905-839-9511 hm
416-729-4766 cell
e-mail gsapounakis@hotmail.com I'm in Pickering Whites rd and Finch
email sent
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  #53 (permalink)  
Old 07-24-2012, 08:52 AM
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horespower stumped

IN regards to timing i have 18 Gedgrees initial 36 total however i have my vaccum advance set to port vaccum and the timing raises to 53 degrees I have read in David Vizzards books that that is what a sbs with a large cam needs once were up to highway speeds,would port or full vaccum be better ,not only for mileage but for plug cleanliness and throtle response.
On the dyno though with no vaccum advance i picked up 27 ft-lbs more torque at the wheels,as well is it better to use nylon or plastis scews for the rotor and or weights so that there will be no spark jumping or arching,sometimes after 2 or 3 WOT runs,foe some reason it always happens at the track, I'll get a little hesitation regardless of the amount of time at WOT but if I let off momentarily everything rights itself back up,i've checked my fuel pressure and it does not drop at WOT under load it stays at 6 psi would jet extensionsand the right floats for clearance possibly help,my wires are brand new and tuked and taylored as far away from heat sources as possible with loom separators attached to the valve covers,I know some of you are not fans of taylor wires but they have the most clearance on the plug boot side of any 90 degree boot that i know of Ive melted MSD's and morosos and accel boots but the taylors seem to be doing fine.
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  #54 (permalink)  
Old 07-24-2012, 11:09 AM
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generally I like to limit the max amount of possible vacuum advance at high manifold vacuum ( deceleration) to a max of 12deg.
You do that by physically limiting the travel of the vac advance arm.
Then, very critical is setting the rate of advance in out reletive to engine load and manifold vacuum.
The dials in the amount of vacuum advance at hiway cruise speeds
with moderate/light engine loads. and how the advance falls off (slope) as
you lean into the throttle. This found by drive testing using a vacuum gauge.
takes a bit of adjustment to get it right.
(Vac advance diaphram spring tension adjustment) every car is different.

Vacuum advance should not effect WOT power at all as there should be no added advance by vacuum when at WOT. Something is wrong if you saw a 27ft/lb difference by unplugging the vac advance.
Something is up with the vac advance or cap rotor phasing.

Ported/full vac source. Thats up to you.

Timing curve looks ok. I use more initial on a auto trans car but you have a 4 speed. so 36deg total is good. Further track testing (on good 94 octane gas)
will find the best total based on draq MPH results. 34-35-36-37.
Some cars see a difference, some don't. Then, on the street you can detune it a bit if you want. -1 or -2deg.

Vacuum advance and how it is mounted (linkage arm) effects the cap rotor phasing. because it moves the mag pickup.
Rotor phasing must be correct within a usuable range or rotor cap crossfireing will occur. Limiting the vacuum advance from 53 to around 46-48 helps as the motion is limited. 10 to 12deg vac advance max travel.
Rotor phasing must be checked and may need adjustment any time misfire, crossfire or other ignition issues are suspected.
Wide spark plug gaps greatly increase the likely hood of rotor cap crossfire and arcing. You never need more than .035".
More than this .035" contibutes to under cap arcing carbon tracking,ionizing, shortens rotor /cap life ... especially when combined with incorrect rotor cap phasing.

Once carbon tracking arc over is established the cap and rotor has to be replaced. It cannot be cleaned once carbon tracked from arcing.

These distributor issues can have a big effect on WOT power and drag performance.
Big ignition power, MSD and wide spark plug gaps both casue more problems
than not.
Big ignition gaps are not your friend.
electricity always goes the easiest path to ground.
The bigger the spark plug gap the more likely to arc to ground in the cap.
and Ionize the cap.

MSD makes it even worse.

.035" gap max. Runing a MSD actuall shortens the service life of the cap and rotor requiring more frequent cap rotor replacement.
You must use the highest quality cap and rotor and replace it often.
when using a MSD box.
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  #55 (permalink)  
Old 07-24-2012, 11:18 AM
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the fact that you saw lame inconsistant power on the dyno+ cap rotor arcing evidence + a diffeernce in WOT power with vacuum advance unplugged
Show there definatly is a distributor problem.
This is the kind of small stuff details that kills power and performance.

Cap rotor phasing check:
is done using a windowed distributor cap so you can watch the rotor motion with a timing light.

It is adjusted by moving the at rest position of the vac advamce arm and mag pickup ring.

http://www.hotrodders.com/forum/atta...chmentid=33618

I always use rear jet extension. Often mechanical fuel pumps create inconsistent drag times as they get heat soaked.
(and inconsistant chassis dyno test results too)

The overheated mechanical pump (after a few passes) boils the fuel, creating bogging etc at the track.

i highly recomend a electric fuel pump for track use. Its the pump/fuel lines/ hot headers fuel system hot soak while sitting in the staging lanes that causes the heat problems and inconsistant performance with a mech pump.

i use and recommend carter electric pumps.. for a lot of reasons....

Last edited by F-BIRD'88; 07-24-2012 at 11:35 AM.
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  #56 (permalink)  
Old 07-25-2012, 07:22 AM
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horswpower stumped

Okay I regapped my plugs to .35 even though the gm manual for 1980 says .45 with HEI. .35 for points But I went with your advice,however I just changed my plug boots 2 weeks ago and when I took them off the plugs to regap them the plugs were clean on the tips and tan in colour but the porcelan part of the plug was covered with carbon should that not be the cleanest part of the plug since it is covered buy the boot..
as for thr the prevvious comment the 1st 2 runs were my best then
I ran into those studdering problems after the the car /fuel lines got hot, makes .sense
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  #57 (permalink)  
Old 07-25-2012, 07:53 AM
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Carbon buildup on the outside porcelain shaft of the plug which is covered by the spark plug wire boot, indicates the header gaskets are leaking.

Once in a while you get a defective spark plug where the seal between the metal shell and porcelain body is leaking. So combustion gases are allowed to escape.

More likely its header gasket leaks. Oil on the outside body of the plugs or on the spark plug threads is leaky valve cover gaskets.

The only part that should show black powdery carbon is the very end of the metal threads of the spark plug shell.
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Old 07-30-2012, 08:03 PM
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stumped

changed the cap & rotor also canged the #2 wire in side yhe old cap all the contacts had carbon and welding type marks but the #2 looks like it had been tig welded so far so good at 2500 i hammer it and she lights em up asfor the phase travel on hard deceleration i show 20 inches vaccum on 1/2 throttle or more vaccum goes to zero.
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Old 08-02-2012, 10:12 PM
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sapsZ28

any advantage to locking out the timing and if so how is it done,As well after changing the cap and rotor and trimming the wires with proper looms,new hei boots etc I now have a constant zipper type sound coming from my stereo when the engine is runing ,but not under batery power ,
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Old 08-02-2012, 11:20 PM
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chokin it.

I would aim for the exhaust size first, let it exhale, size it up.
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