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  #31 (permalink)  
Old 10-28-2012, 11:43 PM
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theres a lot of labour in a race engine.

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  #32 (permalink)  
Old 10-29-2012, 10:50 AM
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Quote:
Originally Posted by F-BIRD'88 View Post
Was this car in storage..? fuel gone flat?

Engine must be dead cold to remove the plugs.
Don;t for get the antisieze for the new plugs.
You will need a timing light.
Yes it say for about 8 months..I added about a gallon of fuel but didnt check to see if there was old fuel in it. when I started to try and run it, I smelled the race gas that was in there, so it had fuel in it. Im going to clean out all the lines and carb first. I have an adjustable timing light I purchased after the last fiasco. (which by the way turned out I was 1 tooth off on my timing after replacing the dizzy but the carb was still defective and poorly machined.)

This car sat just as he put it away and had about 40 hours of track time on it in the past 3 years. It was set up for road racing and has seen track time at Limerock and Poccono raceways. The previous owner said he had it up to 160. I will post more pictures, it is set up to go..

I spoke with the guy that built the motor and he said it is closer to a 389 cause the block was checked and was extra thick so they went .40 over. However the owner said he thought it was closer to a 421 based on his calculations with the head chambers..I dont know what heads are on there, they say "pontiac" on them and look aluminum..

The dizzy on there is a MSD pro stock one and has no vacuum advance that I see, also the timing should be set correctly for the engine by the previous owner, so Im assuming just setting the base timing over would suffice to get it up and running.





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  #33 (permalink)  
Old 10-29-2012, 11:06 AM
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If that car sat for 8 months without the valves being backed off,you will likely need new valve springs.Also if its a race only distributor it might have the timing locked out. check that when its running again.
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  #34 (permalink)  
Old 10-29-2012, 03:20 PM
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Quote:
Originally Posted by vinniekq2 View Post
If that car sat for 8 months without the valves being backed off,you will likely need new valve springs.Also if its a race only distributor it might have the timing locked out. check that when its running again.
Why would I need new valve springs?
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Old 10-29-2012, 03:31 PM
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Because a few valves were in the open position for 8 months.those springs will be fatigued by now. 600 lift roller springs dont last long anyways.
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Old 10-29-2012, 03:37 PM
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Quote:
Originally Posted by vinniekq2 View Post
Because a few valves were in the open position for 8 months.those springs will be fatigued by now. 600 lift roller springs dont last long anyways.
Well I dont intend on pulling stuff apart just yet, how would I know if they are bad? The motor has less than 40 hours on it.
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  #37 (permalink)  
Old 10-29-2012, 03:41 PM
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The engine wont make power in the upper RPM range. how far up will depend how bad the springs are. example,my 434 in my car has maybe 7-8k over last 7 years and I replaced my springs once.I have a 6k chip in my car for street use.
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  #38 (permalink)  
Old 10-29-2012, 03:44 PM
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roller lifters should be checked every 200 passes if you drag race or equivalent race time on your track.for light street use the parts lasts a lot longer. the distributor gear needs to be checked yearly.Race engines need babying
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  #39 (permalink)  
Old 10-29-2012, 03:57 PM
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Quote:
Originally Posted by Dajerseyrat View Post
Well I dont intend on pulling stuff apart just yet, how would I know if they are bad? The motor has less than 40 hours on it.
some engines are freshed every 1/4 mile...

40 hours may be nothing... or it may be 38 hours on "borrowed time"- that's the joy of running with unknown parts.
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  #40 (permalink)  
Old 10-29-2012, 11:49 PM
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Heres what i see. Go ahead and borrow an on head spring tester. Check em.If it is a solid roller,even 220 seat psi is ok on the street. Take the carb apart and soak it. Make sure all your bleeds are clean. I see it doesnt have screw in idle bleeds, so you can take a pin vise and a number bit and increase the idle bleeds a little,just check the existing size.Check the primary butterflies for position and make sure they aren't covering the idle wells i guess you call em, if they are you can drill the butterflies for more air so they can be closed down. Get the jetting down where its not washing the engine and a low power valve that is 3 or so in. below the idle vacuum so it wont be tipping in. Put a hot enough plug in it to keep the tips clean, like a - 6 ngk.tune the squirters after you get it idling and driving correctly. Make sure you have adjustment on your idle mixture screws, if you can close em down and it keeps running,its too rich idle mixture wise. Just basic get it running stuff. You can worry about cam timing and such until after you get it to respond. It will take a great ignition to keep it going. Lots of initial timing, but before it is hard to start and trys to detonate. Let the engine tell you want it wants, not the neighbors. The cam is a little large on .050 duration for the street and thats what makes em soggy on the bottom(no cylinder pressure at low rpms) That can be somewhat fixed by cam timing,but later on you will porb find out that a more up to date cam is in order
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  #41 (permalink)  
Old 10-31-2012, 08:08 AM
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Quote:
Originally Posted by F-BIRD'88 View Post
Your cam is pretty much what I suspected.
Valve lash: you can chcek this your self. You do not need to adjust it, right now , just check it using a feeler gauge. As long as the lash is aceptable range its good for now.
( you probabily don;t know how to R and R the stud girdles so.....)
As you know I am very particular on correct engine ignition timing on racey engines especially when you want it to idle well and run well on the street.
( SET up for Racing) usually indiates its only set up to run well at WOT without specific attention to race engine idlling etc etc. Lots of improvment there usually.
So replace the plugs , drain all the fuel and replace, and get er fireed back up.
Need to know inital base timing,, Max timng when you rev it up....
Power valves when the diaphram is blown ruptured the power valve leaks fuel ( internal) is always rich
,, fouls plugs oftem caused by a backfire thr the carb ,
Check both PV's diaphram. (stick it in your mouth and suck on it to see if it leaks and operates)
replace if suspect.
Once yu get it up and running ans set up it wouls be nice to take it for a good long hiway run to
"clean it out" ( blow the carbon out) Legal speed hiway driving is good enough.
Get an extra set of new spark plugs and bring them and a plug wrench in case they refoul.
You can run it on 92+ octane pump gas but reduce the timing a bit ( 32 to 34deg max)
with 11:1 cr and full power timing 36-38deg you need 100 octane gas.

It is very likely that this motor does not have enough idle spark timing. ( distributor curve not set up correctly)
Racey engines with 260+deg cams need a ton of timing at idle. as much as 38deg BTDC at idle.
If it don;t have at least 26deg base timing at idle ( more is better) you need to fix that
or it will load up and foul again.

2. because you do not have vac advance the motor wil really like locked out timing
full timing at idle (32 to 34deg for street pump gas) It wil idle much cleaner, not load up and drive much better on teh street. Its a easy set up change on most race distributors.

power valve must stay closed at idle. idle manifold vacuum/power valve vac rating...
power valves must not be leaking/blown diaphram.

That carb body don;t look like a 850. Looks like a 650-700 and the jetting corisponds with that.
Measure the throttle bores diameter and the pri and sec.venturii diameter on the carb body.
You can compare that to the dimentions shown on the holley model list number list (PDF)
This will tell you can mee a lot about what carb body it is and get it dialed in better so it runs clean all the time..
As opposed to "set up for racing".... ( I define that as not set up well at all)

If you have it apart post some picks of the metering blocks. Looks like Percy or...
Probily has removable metering orifices 9 emulsions, idle feed restriction. PVCR etc) idle and hi speed air bleed sizes?
the specs of al this really helps determine the carbs present setup.

which means it may not be right (except for WOT racing) and you can fix that and make it a beauty carb
if you are willing.

When you drive this car do no lug the motor at low rpm. These motrs with this size camashft are not real happy driving at less than 2500rpm. Hi wat cruaising at 3000+rpm is where they like to live. (with 3.08's Id cruise in 3rd gear (4speed)) its not a taxi. It want to run and rev. The usalbe power band of that cam is 4000 to 7000+ rpm keep that in mind.
Avoid needless idleing and low rpm lugging.
Once its set up correctly and cleaned out ( carbon in combustion chambers)) it will run well on the street.


Since the car was sitting replace the fuel filter.. The carb needle seats may need to be replaced too (they go hard and don;t seal) Power valves too,,, don't like to sit. Blow out carb air bleeds with compressed air.

Thanks will do, I replaced the needle and seats and all the carb seals, new accelerator pump diaphragms, but the power valves seemed to be ok so I reused them cause the rebuild kit came with much larger ones. Also my pump shot squirters were .28 and .31, not .21 and .22 ( they were hard to see until I removed them. The metering blocks looked like the ones I had in my old 4150 Dominator.

How do I measure the carb bowls, do I need a caliper? or will a ruler suffice?

Also from what Im getting from your post, the base timing will be higher than the WOT timing? So it will actually be retarding timing as you accelerate?
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  #42 (permalink)  
Old 10-31-2012, 08:11 AM
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Quote:
Originally Posted by F-BIRD'88 View Post
As for assuming that the previous owner set it up right. That is very very unlikely...
The fact that its all loaded up and carbon fouled,, tells all. I have been doing this for some 35+ years. Seen it all.

Trust me, it ain't set up right. details on the carb will reveal a lot.
Gotcha, as soon as we are back to normal here in NJ I will proceed to get gas and start her up and set the base timing, might be a few days cause gas is in high demand with al the power outages here from the hurricane..I will post the results when i do get her fired up..Oh and I picked up the Champion plugs you recommended.
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  #43 (permalink)  
Old 10-31-2012, 09:01 AM
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FYI here is the distributor I have, and I cant find within the instructions how to set the timing curve.

Chevy Crab Cap Crank Trigger Distributor - 8489
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  #44 (permalink)  
Old 10-31-2012, 09:24 PM
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Quote:
Originally Posted by Dajerseyrat View Post
FYI here is the distributor I have, and I cant find within the instructions how to set the timing curve.

Chevy Crab Cap Crank Trigger Distributor - 8489
That's a distributor used for racing so the distributor itself contains no mechanical or vacuum advance capabilities. If you want an ignition "curve", you will need an ignition box that is programmable. It's not unusual for the timing to be set to the max power setting and then an ignition timing retard is used to crank it up.
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  #45 (permalink)  
Old 10-31-2012, 09:37 PM
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Nothing better for the street than a vacuum secondary 780 Holley - like the old 3310 model used in Z-28s; 425 HP 427s and 454s. Easy to tune and can make a good bit of power.
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