Pop N Wood

The "new but rough" paint job is a bad sign. Could be covering up a ton of bondo and rust. This is IMO the most important thing. If the car has a workable body (pay special attention to the floor pans and rocker panels) and suspension then it is worth $500 for that alone. There are a million other things to consider. For instance you never mentioned anything about the engine or type of tranny and whether the pig even runs. No matter how you look at it, a lot of work and time before it is drivable.

Just make sure both wheels move together. An other way is to only lift one rear wheel off the ground then see how many turns of the tire are needed to turn the drive shaft one full turn then divide that number by two.

Yes, someone mentioned the variable valve timing on this site but I can't find the thread. Here is one from Chevy directly (for the trailblazer engine) http://www.chevrolet.com/trailblazer/popup/engine/valve_timing.htm Also found this thread: http://www.hybridz.org/ubb/ultimatebb.php?ubb=get_topic;f=15;t=000236#000001 so sounds like automatic only.

Someone also posted that this engine uses variable valve timing which can be a PITA. Something about the engine computer...

Not to be picky but the more torque you have the less gears you need. And by more I mean a broader torque curve across RPM. Case in point would be a DOHC 4 banger turned to produce max HP at high PRM. For that engine the power band would be very narrow requiring a lot of shifting to keep the engine at max RPM. A blown V8 will have stump pulling torque down low and can thus tollerate a WIDE gear spacing. This is something Grumpyvette has posted links on before. You may want to search through the Chevy V8 forum for torque and gears to get some on line tutorials.

Bump. I wouldn't mind seeing the article too.

If it just the ends then you have excessive resistance between the connector and the cable. Did you buy pre-made cables or crimp on your own connectors? Make certain the crimp is tight and there is no corrosion between the copper cable and the connector. Also clean up everything the connectors touch with a wire brush. Also make sure the battery has a good charge. Get it load tested to make sure it can pass sufficient cranking amps. I guess you could try cranking with the plugs removed. If it is still slow then it is definitely in the starter/battery/cabling/grounds. If it cranks normally, then I don't know what this would prove. BTW, just what is your compression ratio?

The radiator cap is what regulates the pressure. If you blew a hose on overpressure, then replace the cap. But I doubt this will correct your overheating at idle. What type of radiator do you have? For that matter, what engine? Also the Taurus fans are 2 speed. Do you have it on high or low? Tried flushing the radiator lately? Also make sure to use the proper mix of antifreeze and water. Straight water will corrode your aluminum engine parts and doesn't lubricate the water pump. I also like checking the thermostat by placing it in a pot of water on the stove and seeing what temp it opens (and opens fully).

A few months ago a car mag (forget which) ran a series hopping up a 4.3L Chevy V6. They felt this is not a good hot rod candidate due poor flowing heads and the unavailablity of aftermarket parts. Other than that, they did a fairly nice build on the motor so would recommend finding the ariticle if you are serious. here is a past topic discussing the engine. http://www.hybridz.org/ubb/ultimatebb.php?ubb=get_topic;f=15;t=000166#000002

Man, did you guys see the twin turbo 62 Impala in this month’s issue of Popular Hotrodding? http://www.popularhotrodding.com/toc/ What a work of art! The body work and custom panels/dash/belly pan/fender wells/titanium turbo piping/etc/etc/etc are truly an inspiration!

You said a LOT of money? This should get you what you the best of both worlds: http://shop.theengineshop.com/dr/v2/ec_MAIN.Entry10?V1=425763&PN=1&SP=10023&xid=42186&DSP=&CUR=840&PGRP=0&CACHE_ID=0 Big block displacement in a small block. They also offer fuel injection.

Yes. At any given RPM changing the duty cycle will directly vary the pulsewidth. No. Time (in seconds) per revolution = 1/(60*RPM) since there are 60 seconds in a minute. For milliseconds, simply mulitply the above by 1000. Note there may be several injector firings during each revolution of the crankshaft. To convert engine RPM to injector firings per second you need to know whether you have a 2 or 4 stroke engine and the number of unique injectors being controlled by the computer. Well put. I hadn't thought about it but that states it very clearly. To nitpick it is a measure of fuel flow rate. Think of a fuel injector as a garden hose that is either fully on or fully off. When turned on, the hose passes water at a certain rate (say 10 gallons per minute). If you turn the hose on for 1 minute, you will fill a 10 gallon jug. Thus the total volume of fuel passed is the flow rate mulitplied by the injector "on" time. Or you can fill that same 10 gallon jug by turning the hose on for 12 seconds, off for 48 seconds, then repeat 5 times. It now takes you 5 minutes to pass the same amount of water because you only have the hose on for 12 seconds out of every minute (the duty cycle). Sooo you have effectively cut your fuel flow rate from 10 gallons/minute to 2 gallons/minute (i.e. by a factor of the duty cycle). What TimZ is saying makes sense. For a single intake stroke, the cylinder will inhale a certain volume of air. This volume of air will need a specific volume of fuel, i.e. a specific injector "on" time or commanded pulsewidth. As engine RPM increases, the number of intake strokes per second increases, but not necessarily the volume of air being inhaled by each stroke. This is more dependent upon engine vacuum than RPM. Thus as the RPM changes, the pulsewidth (volume of fuel per stoke) is the same, but the pulse come at a faster rate, hence higher duty cycle.

This brings up a question I have alway wondered about. If you fit the cage tightly inside the car, how do complete the welds around the back side of the joints? Weld in "gussets" with the pipes outside the car, then piece everything together like tinker toys inside the car and only weld half way round each gusset? Can anyone recommend a good book on building effective cages?

First thing I thought of for measuring the change in toe in is a laser pointer (or two). Simply secure the laser pointer to the side of the wheels and mark a point on the front of the garage where it hits. Move the suspension through it's travel and note how far in and out the beam travels. Just make sure the car is on blocks under the chassis so nothing moves.

Want to second this. "carbon scoring" means dirt on the inside of the cap is causing the cylinders to cross fire. If a plug fires when the intake is open, backfire through the intake. Same for cracked ignition parts (wires, coil, dist cap, etc.) You're problem could be multiple things. Get the spark situated first. If it was carburated I would say stuck needle valve/float. Maybe stuck injector (or two?) Wasn't there also a guy on here a week or two ago who could idle but died as soon as he touched the gas? Turned out to be the distributor module was bad (forget the name).

I think Lone suggested this as one option for cutting http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=5983

I guess I should add a qualifier: if both fans are moving the same amount of air, then the electric and mechanical fans place the same load on the engine. (The blade efficiency has a play here but let's assume they are the same.) You can't get away from this, the power has to come from somewhere. If the dyno run with the electric fan resulted in higher HP, then the electric fan is simply not moving as much air and thus doesn't have the cooling capacity of the mechanical. It is possible to have too much air, at which point you are needless robbing engine HP. This is obviously much easier to do with a mechanical but the same thing can happen with an electric. The big advantage to an electric is you can control it from a computer or thermostat and only use it when needed. But if you need the air flow to keep from overheating, then you are putting the same load on the engine either way.

Electric fans have always just seemed wimpy to me. I personally just like the look of the mechanical, bulky as it is. But like I said I am in the minority on this one. I also like knowing you have the maximum cooling possible from the mechanical fan. The mechanical fans don't put any more load on the engine than the electric. That is a non-issue. Conservation of energy...the electric fan loads the alternator which in turn takes HP from the engine to run. Now an electric fan is more efficient when the engine is not warm since it can be turned completely off. But when hot they are both the same. And I know the LT1's don't lend themselves to mechanical fans (although the LT1's in the Caprices have a mechanical fan driven off an accessory pulley). In that case I would run an electric also. I am not trying to talk anyone into an mechanical. Just want to make sure everyone makes an informed decision. One other recommendation. Pete P had heating issues until he got all of the air out of his cooling system. I think he had to jack up the front of the car to “burp” the last of the air out of the radiator (the fill spout is below the highest point in the engine?). Pete also recommends checking the accuracy of the temp gage. It’s all in the archives.

I think most shipping places are pretty strict about draining all of the fluids too. On a related note, I had a radial arm saw shipped from the midwest. The only people who would ship anything "electrical" was Airborne Express. That thing cost $85 in shipping about 5 years ago. Hard to believe it weighed anything close to a T56 with the clutch assembly.

I agree. I have had the conversation a few times in the past. As most guys will tell you, the electric fans work. My minivan has electric fans and in the summer I can't stand next to the van when the fan comes on... the heat blowing out is uncomfortable on the ankles!! BUT how many times have people on this site recomended that some one replace their black magic fan for the Taurus one? When I first got on this site I thought my only option was going to be an aluminum radiator and an electric fan. After asking a few questions I realized I can keep my recored, 3 row stock radiator and a mechanical fan. I think the JTR guy got this one right. In my opinion (and it is only my opinion) the only reason to go to an electric fan is if the installation doesn't allow a mechanical one. Do the math. 35 amps at 12 volts is only a half horsepower. You can get a lot more power (hence airflow) out of a mechanical fan than an electric one. But if the electric is all you need, then it is all you need. Just wanted to make sure everyone is aware of the options....

The Black Magic fan has received some sharp critisim on this site (don't believe me, check the arichives). Most guys recommend dumping the black magic for a Taurus fan. BUT a bad fan usually spells overheating at idle, not speed. My guess is you are either having airflow problems or have an inefficient radiator/water pump. The Z's are notorious for not getting proper air flow through the radiator. Install a belly pan (I think the MSA catalog calls them chin pans). This smooths out the turbulence underneath the car that prevents air from flowing through the radiator at speed. Beyond that, many guys recommend sealing all possible air routes around the radiator. Especially the areas between the sides of the radiator and the body. Check your thermostat by placing it in a pot of water and see what temp it opens up. Also make sure it fully opens. Flush the radiator. An old car can be gummed up with stop leak from previous owners. Also check or replace your radiator cap. These things try to maintain about 15 PSI of pressure in the system. A bad cap will not do this. Now what has me confused is why is your upper radiator hose collapsing? The water pump suction should be on the lower hose (right? I am not sure) so this should be the one collapsing. Must be one hell of a pump to suck all the way through the radiator and collapse the upper hose.

ZR8ED Have you ever posted pictures? I would be EXTREMELY interested in studying details of your design. I am particularly interested in how the cage clears the dash and whether you have a bar traversing the dash and connecting to the front strut towers. Plus any ideas on how to build a cage with stock interior panels would be appreciated. I want to stiffen the chassis without doing a total dukes of hazards to the car.

You might want to look at some of Gumpyvette's old postings. He posted a LOT of information concerning heads. I remember one of his favorites (for the money) were Canfield heads.

I always hate to refer people to the archives but this one has been discussed numerous times and a lot of good advice is in the old discussions. I think the general concensus is most people are not willing to pay what it would cost a good shop to do this work. Likewise, most shops won't do it for the same reason. But if you are patient, deals come up all the time on converted Z's. And the answer to most of your questions is "yes".

NO NO NO! Keep both hands on the wheel when this is happening! You already know you have a pair when the tires light up!