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Where'd the horsepower go????


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I'm feeling ever so humbled!!! Well.........I'll fill out the answers to a lot of this stuff tomorrow. I'll run through the list of checks. Check what I can, and shoot some results. Hopefully, I'll have the booger good to go for my scheduled dyno day on the 4th of March!!

 

Grumpy, U DA MAN!!

 

(and everybody else that helped thus far too!!)

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ok, here's what I've got thus far....

 

did you get the clearances checked, ---- yes, what we could with the engine already preassembled

coil bind, ------ None

rocker to rocker stud,clearance? ------ can't remember, but everything looked good prior to installation

whats the retainer to valve guide clearance? ------ see above

whats the valve to piston clearance?? -------unknown

did you do a compression check on ALL 8 cylinders? ---- today, 145psi all around

have you checked CAREFULLY the cam lift to see if a lobes worn? ---- cam was brand new, and was left unchecked

how did you adjust the valves? ---- zero lash

did you degree in the cam or just install it DOT-TO -DOT? ---- dot to dot - yes

have you checked the exhaust back pressure? do you run a cat /converter? ----- no cat/converter, dual 2 1/2" all the way back, back pressure unchecked

what are the plugs gapped at? ----- .045 (checked today to confirm)

what do they look like as to the burn and heat condition? -------- Running VERY rich

have you checked for vacuum leaks? ------ none could be found

what temp does the engine run at? -------- constant 190

is the trans fluid at the correct level? -------- perfect

are YOU 100% sure, not 99% sure that the trans control cable is adjusted correctly? ------- no, not 100%. But I'm getting popping (when either rich or lean in the driveway as well)

have you had someone sit in the car and with the engine OFF, floor the gas petal to see if the carb opens fully and the secondaries open EASILY with mild finger pressure? -------- felt good and easy

is the power valve in the HOLLEY (IF THERE IS ONE in that model) working correctly? ------ unchecked as of yet

are the accellerator pumps(pump)set up to the maximum volluum and durration? ----------- unknown as of now

whats your fuel pressure at idle? --------- constant 6psi

whats your fuel pressure at wot ----------- very little fuctuation from above

whats your float level? -------- unchecked as of yet

whats your power valve and jet numbers? -----------unknown at this time

are you running a points or electronic ignition? --------- HEI

coil type? --------- Summit 50,000 volt upgrade kit

have you had the distributor looked at and curved to give full advance (about 36 degrees total) by 2900rpm? ---------- no, not yet

( the ignition should be set at idle at between 6-about 8 degrees at about 700rpm?????) --------- did you say 6-8??? I'm up to 18 right now

whats the TESTED CONVERTER STALL SPEED? --------- untested but was told its a 2000 ss lockup type

are you SURE the ignition ADVANCES as the rpms build? ------ no, see note below

does disconnecting the vacuum to the carb help or hurt the responce? engine idled up to about 1500rpms

can you give me a vacuum reading at idle and at wot? ------- about 16.5 at idle, and went as high as 20 at about 4,000 rpms

whats the OHMS reading on your ignition wires?(end to end) -------untested

whats the voltage your batterys got,what the altenator put out in voltage? -------12 volts. 14 when cruising

 

Ok, so I did some checking today. On a whim, I pulled over and moved the vacuum advance hose to the full vacuum as opposed to the timed vacuum port on the carb.....No change. I then plugged everything off completely ........ no change.... grrrrrr vacuum advance blown????

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ok, here's what I've got thus far....

 

did you get the clearances checked, ---- yes, what we could with the engine already preassembled

coil bind, ------ None

rocker to rocker stud,clearance? ------ can't remember, but everything looked good prior to installation

whats the retainer to valve guide clearance? ------ see above

whats the valve to piston clearance?? -------unknown

 

ok up to here your basically saying it was guessed at because it turned over without binding, or breaking parts, personally I can,t beleive your getting away with out problems on un-modifyed vortec heads

 

did you do a compression check on ALL 8 cylinders? ---- today, 145psi all around

 

good at least its consistant

 

have you checked CAREFULLY the cam lift to see if a lobes worn? ---- cam was brand new, and was left unchecked

guessing again,but your probably ok

how did you adjust the valves? ---- zero lash

did you degree in the cam or just install it DOT-TO -DOT? ---- dot to dot - yes

have you checked the exhaust back pressure? do you run a cat /converter? ----- no cat/converter, dual 2 1/2" all the way back, back pressure unchecked

guessing again,but your probably ok

 

 

what are the plugs gapped at? ----- .045 (checked today to confirm)

 

good!

what do they look like as to the burn and heat condition? -------- Running VERY rich

now we have a symtom to look at!

have you checked for vacuum leaks? ------ none could be found

what temp does the engine run at? -------- constant 190

GOOD, useful info!

is the trans fluid at the correct level? -------- perfect

GOOD, useful info!

 

are YOU 100% sure, not 99% sure that the trans control cable is adjusted correctly? ------- no,

again,GOOD, useful info!

 

not 100%. But I'm getting popping (when either rich or lean in the driveway as well)

again,GOOD, useful info!

have you had someone sit in the car and with the engine OFF, floor the gas petal to see if the carb opens fully and the secondaries open EASILY with mild finger pressure? -------- felt good and easy

here I think your potentially having a problem, as your running rich which may mean the secondaries are slow to open or not opening fully if at all,as the vacuum goes up so does the fuel flow which may account for the rich plugs

is the power valve in the HOLLEY (IF THERE IS ONE in that model) working correctly? ------ unchecked as of yet

you need to check

are the accellerator pumps(pump)set up to the maximum volluum and durration? ----------- unknown as of now

you need to check

 

whats your fuel pressure at idle? --------- constant 6psi

whats your fuel pressure at wot ----------- very little fuctuation from above

again,GOOD, useful info!

 

whats your float level? -------- unchecked as of yet

you need to check

 

your guessing again,and your probably NOT ok with the float levels

 

whats your power valve and jet numbers? -----------unknown at this time

guessing again,but your probably NOT ok

 

are you running a points or electronic ignition? --------- HEI

coil type? --------- Summit 50,000 volt upgrade kit

again,GOOD, useful info!

have you had the distributor looked at and curved to give full advance (about 36 degrees total) by 2900rpm? ---------- no, not yet

( the ignition should be set at idle at between 6-about 8 degrees at about 700rpm?????) --------- did you say 6-8??? I'm up to 18 right now

guessing again,but your probably NOT ok, this seems like a problem but it may be your not useing the correct test procedure, the base timing should be significantly less than the ignition advance at 2900rpm which should be close to 36 degrees total, any more than 10 degrees makes me think your ignition curves WAY OUT OF SPEC

 

whats the TESTED CONVERTER STALL SPEED? --------- untested but was told its a 2000 ss lockup type

 

its a very simple test

look at the links I provided

are you SURE the ignition ADVANCES as the rpms build? ------ no, see note below

again,GOOD, useful info!

does disconnecting the vacuum to the carb help or hurt the responce? engine idled up to about 1500rpms

can you give me a vacuum reading at idle and at wot? ------- about 16.5 at idle, and went as high as 20 at about 4,000 rpms

here we may see a problem, vacuum readings should drop off as the carb venturies open fully, not get higher, (yes IM VERY AWARE the vacuum readings jump up untill the secondaries DO OPEN fully,)this tends to make me think the secondaries are slow to open or are not opening, Id suggest looking into that, but the ignitio seems to be the fist problem area

whats the OHMS reading on your ignition wires?(end to end) -------untested

your not likely to have a problem here but its easy to test and IS a potential problem

whats the voltage your batterys got,what the altenator put out in voltage? -------12 volts. 14 when cruising

again,GOOD, useful info!

 

Ok, so I did some checking today. On a whim, I pulled over and moved the vacuum advance hose to the full vacuum as opposed to the timed vacuum port on the carb.....No change. I then plugged everything off completely ........ no change.... grrrrrr vacuum advance blown????

23 Hours Ago 12:53 AM

Poundz9oh9

 

Id get a ignition upgrade or the current distrib repaired, personally I prefer the MSD stuff for a basic ignition

TECH LINE: 915-855-7123

 

 

http://www.msdignition.com/ignition_4_6200.htm

 

http://www.msdignition.com/dist_1.htm

 

see what testing vs guessing does, it tends to limit your potential problem areas, we now have at least the basic info to suspect the ignition advance curve is way out of spec, or non-functioning, and will need repair or replacement,(personally Id install a MSD dissy and 6200 ignition control if I could afford it_ if I was you) and the carb secondaries may be opening too slowly if they open at all, and the floats and power valve may be wrong or mal adjusted

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I will MOST DEFINATELY get on the rest of those checks as soon as I get back from the field. I'll be gone the whole week playing in the woods with the new soldiers.

 

I've been wanting to go MSD for a while now, and will prolly get it mid march. Not in time for my dyno day, but ya know money talks. I'll go through the carb as well. I think I'll just have it rebuilt with the upgraded jets, power valve and accellerator pump. And call it good, I'm not familiar with carb internals and frankly they scare me. Is there anybody here or on the internet that you guys could recommend I send it to??? Does Corzettes suggestions about the jets seem about right?

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I have seen new flat tappet cams go flat on the break in. Not an issue if you are using a roller cam. New cams can go bad very quickly if then is some kind of oiling or clearance problem.

 

If the Holley is doing the same thing as the old carb then it is most likely not a carb issue. Nice carb you got there, by the way. I would use 70 jets up front to start with.

 

If the Vortec heads were not modified for more lift then that would be a major problem. You can check the clearance with the head on the engine by removing a few valve springs. I use the compressed air in a cylinder method to remove valve springs. This will allow you to remove the valve springs in order to check retainer to seal clearance and spring installed height. Check the clearance by lowering the valve and reatainer (no spring and no air pressure) all the way to the seal and subtact the lowest point from the highest point (valve all the way up). Then with the spring off, you can check coil bind height using a bench vise and a micrometer.

 

I fill my cylinders with compressed air by removing the "one way valve" in a standard compression tester hose and connect the gage end of the hose to my air compresor. FYI, the compressed air holds the valve up on the seat when the spring is removed.

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  • 1 month later...

Ok, MSD stuff (Dizzy, Coil and 6A) is ordered and should be in the car by Thursday afternoon!! Will post more updates then!!

 

Also, was getting ready to order the holley secondary quick change kit as well.

 

On a side note, I obtained a Holley 770 Street Avenger body, so if the ignition and spring kit don't help, that's where I'm going next. Get a good rebuild kit and have at that carb, which, by the way I ordered one of those Holley rebuild books ( http://www.motorhaven.com/catalog/product_590_Holley_Rebuilding_and_Modifying.html )................ and yeah and I'm still intimidated.

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call MSD

 

915-857-5200

 

TECH LINE

 

 

 

915-855-7123

 

The MSD Tech Lines are now open Monday through Friday

7am to 6pm Mountain Standard Time

 

 

and ASK! , Ive run the blasterII coil in the past,but IVE also done ALOT of other mods, its best to ASK the manufacturer so you DON,T SCREW it up!

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Thanks Grumpy. I don't know why I come to you guys first for this stuff when tech lines exist, just a natural reaction I guess.

 

Oh, by the way. They both will work fine, the only difference they said was that the SS coil has more current. I turned around and ordered the SS one anyway, so I'll just send the Blaster 2 back when it gets here, or just keep it as a spare. Wish me luck!!

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Sounds like the motor "loading up" with fuel, the gasp out of the carb is the spark plugs misfiring trying to burn clean then Ok. Do you have the lock up clutch connected in the trans?? If so is it connected for overdrive only or in any gear?? The torque converter issue goes like this. Unless your drag racing the car you want a converter with a LOW stall speed with a light car like a Z, because it makes it a little harder to spin the back tires in the rain, snow, with a street driver.

 

This may sound stupid but are you sure nothing else is wrong with the rolling chassis, like hung up brakes???

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This may sound stupid but are you sure nothing else is wrong with the rolling chassis, like hung up brakes???

 

I'm POSITIVE it's nothing else other than a drivetrain issue! :)

 

Now the torque converter, that's a different story ... I always thought that may be the culprit or a contributing factor. It really wouldn't surprise me if it was bad too or the tranny wiring messed up. The motor it was attached to was an anchor that I paid WAY to much for (thanks again Mr Savage). So needless to say.......it wouldn't be surprising if it's crap. Now, i never messed with the internal lockup stuff in the tranny. I pretty much just plugged it up and ran with it. I've got my eye out for a WC T5, or T56, to completely eliminate the auto option (never wanted it to begin with, but it came as a package), but I'm always keeping my eye out for a decently priced TC too so I can attack that next.

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have you had the distributor looked at and curved to give full advance (about 36 degrees total) by 2900rpm? ---------- no' date=' not yet

( the ignition should be set at idle at between 6-about 8 degrees at about 700rpm?????) --------- did you say 6-8??? I'm up to 18 right now

[b'] guessing again,but your probably NOT ok, this seems like a problem but it may be your not useing the correct test procedure, the base timing should be significantly less than the ignition advance at 2900rpm which should be close to 36 degrees total, any more than 10 degrees makes me think your ignition curves WAY OUT OF SPEC[/b]

 

Ok, looking at the distributer paperwork (MSD stuff came today), I see the "out of the box" advance curves. Now, the ready made curves in the paperwork ( page 3 of this http://www.msdignition.com/pdf/8360_frm%2023793.pdf ) shows that the top total advance that I can limit it at is at 28*. How do I get to the 2900rpm total advance of 36*? Also on that page, on the example of "E" or "F", which one do you think the best bet would be?

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I think the (F) advance curve will get the best results if you set it up that way so the TOTAL advance reaches about 35-36 degrees advance , let the initial advance at idle fall where ever it may as long as its in the 6-12 degrees advanced range, (6-9 is normal here)but be aware that crappy fuel octane may get you into detonation under heavy accelleration on hot days

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