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Old 09-16-2014, 07:24 PM   #1
Longbedstepper
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69 chevy feeling tired!

Hi, this is my first post on this forum.
About 6 months ago I picked up a clean 69' long bed step side 4x4 chevy half ton. The truck has a 350 and a sm465 with 44,000 miles. It was 100% stock other than a 4" rough county lift and a set of 33s with chrome wheels. Motor was completely stock. When I first got it it ran good, but I could tell it needed tuned up. I took the old nasty quadrajet off and replaced it with a 1406 edelbrock. That made a noticable difference. Then last weekend I replaced the old points distributer with an msd hei with new wires and plugs and a edelbrock performer intake. My problem is when you step on the gas, all that happens is it gets louder. Doesn't pull any harder, may even lose power? I made sure the timing was right (10*). A lot of people telling me with the tires and 4 speed that's all the power I'm going to get but the thing feels very weak. I could really appreciate some advice!
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Old 09-16-2014, 07:47 PM   #2
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Re: 69 chevy feeling tired!

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Originally Posted by Longbedstepper View Post
Hi, this is my first post on this forum.
Welcome! Glad to have another aboard.

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Originally Posted by Longbedstepper View Post
When I first got it it ran good, but I could tell it needed tuned up.
I'm not sure how both can be true, but ok....

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Originally Posted by Longbedstepper View Post
I took the old nasty quadrajet off and replaced it with a 1406 edelbrock.
That's just trading a Q-Jet for an AFB. The Q-Jet is a better carb, but needed repair. A new or rebuilt Q-Jet (or if that's the original carb for that engine, that particular carb rebuilt would be the best) would have been a more direct replacement, but I guess the Carter will work too.

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My problem is when you step on the gas, all that happens is it gets louder. I made sure the timing was right (10*)
Well a small block with big tires will never be fast, but it sounds like you're comparing it to itself, so probably OK.

I would suspect you've messed up the ignition timing. Could be a bad distributor, user error, or any number of things.

You may have verified that you have 10 degrees of initial advance, but its probably more important to know what the total advance is and when that kicks in.

Disconnect and plug the vacuum advance port at the carb. Have someone hold the engine at about 3000 rpm. Carefully check your timing and it should be around 34 degrees. If its not, your mechanical advance is hooped. If you do not have a timing tape on the balancer you will need a dial-back timing light to check it.

I'll presume you checked that you have spark at all 8 cylinders and that no wires are reversed.
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Old 09-16-2014, 07:58 PM   #3
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Re: 69 chevy feeling tired!

Thanks for the reply!
The distributer I installed was brand new, so I'm fairly sure it's all working right but I have not verified that.
My plug wires are plugged in correctly. I will check the total timing this weekend and see what it reads. Thanks!
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Old 09-16-2014, 09:55 PM   #4
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Re: 69 chevy feeling tired!

Hey Longbedstepper

to the forum and from Greeenville Ohio.

on owning a classic
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Old 09-16-2014, 10:57 PM   #5
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Re: 69 chevy feeling tired!

Hey Longbedstepper

to the forum and from Lenexa, Ks.

on owning a classic
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Old 09-16-2014, 11:08 PM   #6
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Re: 69 chevy feeling tired!

Thanks guys
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Old 09-17-2014, 02:32 AM   #7
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Re: 69 chevy feeling tired!

Welcome always glad to have another long stepper on here
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Old 09-17-2014, 02:44 AM   #8
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Re: 69 chevy feeling tired!

Hi, Longbedstepper-

What did you use for a power supply wire on the new HEI?

HEI takes more juice. If you used the old points coil power supply from the ignition switch, it's not enough. Use that wire instead for a relay trigger, get a 30 amp relay and run power straight from the battery or junction block or even the starter and use a heavier gauge wire to the HEI.

This might fix your problem. If not,

NOTHING wrong with the Edelbrock carb, it works very similar to the quadrajet. MSD distributors are the BEST. If you got their "good one", then you can put the parts in they come with and custom tailor your advance curve to suit your engine. If it's 100% stock it's probably around 9:1 compression so set your timing at 36 total and that needs to come in before 3,000 RPM. If it cranks slow, cut it back a couple degrees. It would be interesting to know what part number MSD distributor you have and where your base timing ends up after you set the total.
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Old 09-17-2014, 11:37 AM   #9
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Re: 69 chevy feeling tired!

I did use the old coil power wire for the distributer. Il try using some heavier wire and connect to something with some more power. The distributer I got from oreillys and came with some odds and ends that I assume are for tweaking the timing. It wasn't a cheap distributer but I can find the part number for you later.
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Old 09-17-2014, 02:00 PM   #10
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Re: 69 chevy feeling tired!

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I did use the old coil power wire for the distributer. Il try using some heavier wire and connect to something with some more power. The distributer I got from oreillys and came with some odds and ends that I assume are for tweaking the timing. It wasn't a cheap distributer but I can find the part number for you later.
The problem with "connect to something with some more power" is that it needs to be switched through the ignition switch and that ignition switch is not designed for the extra load. Use the old coil wire to trigger a relay that uses power direct from the battery. If you have any problems with that wire not tripping your relay (people use it as a trigger all the time) just replace the resister wire with regular wire.

So if it came with some "odds and ends", like some off-set bushings and some springs for the advance, and it "wasn't cheap", it's probably the nice one no need for a part number.

Set your total timing to 36 degrees and let me know where your base timing falls in, and if it pings and under what conditions.

Ideally, you want about 10 degrees base, 36 total (vacuum advance plugged), (26 degrees mechanical plus 10 degrees base), and 50-56 degrees cruise (26 degrees mechanical plus the 10 degrees base plus 14-20 degrees vacuum advance) (cruise timing is where you get your best gas mileage from). You want all the timing you can get away with, without pinging.

If, under any of these conditions you get ping (depends on rear gear ratio, tire size, weight, drag, etc) then under those conditions the timing will need to be reduced to achieve ideal timing.

If you set it for optimal gas mileage, and do towing or heavy loads, you may need to back it down a little to keep from pinging under those conditions (overall timing).

Nice thing is, with the good distributor, it has instructions on how to set each of those parameters and know what to expect when you do it.

Last edited by mechanicalman; 09-17-2014 at 02:08 PM. Reason: proper english
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Old 09-17-2014, 02:12 PM   #11
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Re: 69 chevy feeling tired!

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HEI takes more juice. If you used the old points coil power supply from the ignition switch, it's not enough.
Why do you believe this? I quoted the GM specs above, 4A for breaker points and 5A for HEI. If a switch can handle 4A it can handle 5A because they were designed with engineering head room. They didn't build them to run on the ragged edge. You sound like the kind of guy that probably owns and knows how to use a multimeter, hook it up.

I'm not going to get into the whole resistance thing again with you, but will note that there is a resistance wire. Keep in mind, however, that during cranking it has to deal with full 12V as it bypasses the resistance wire by "setaling" ignition power from the starter (to be precise, the output lug of the solenoid). But it's all going through that ignition switch. So it had to be able to deal it. Maybe the crank circuit of the ignition switch is significantly beefier, I've not taken one apart to check.

And yes, the Edelbrock is a fine carb, but it was designed at least a decade and probably more before the Q-Jet (I had an AFB on a 413 Wedge and it ran great).

The only thing I would argue is that the Q-Jet was built with the lessons learned from the AFB, but the opposite isn't possible. The Q-Jet was designed to emulate the tri-power designs of the day (primaries representing the center carb and the huge secondaries the outboard carb). You can observe that only the Corvette retained tri-power for marketing purposes once the Q-Jet was available. Otherwise they went to Holley (302, LS6, etc).
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Old 09-17-2014, 03:37 PM   #12
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Re: 69 chevy feeling tired!

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Why do you believe this? I quoted the GM specs above, 4A for breaker points and 5A for HEI. If a switch can handle 4A it can handle 5A because they were designed with engineering head room. They didn't build them to run on the ragged edge. You sound like the kind of guy that probably owns and knows how to use a multimeter, hook it up.

I'm not going to get into the whole resistance thing again with you, but will note that there is a resistance wire. Keep in mind, however, that during cranking it has to deal with full 12V as it bypasses the resistance wire by "setaling" ignition power from the starter (to be precise, the output lug of the solenoid). But it's all going through that ignition switch. So it had to be able to deal it. Maybe the crank circuit of the ignition switch is significantly beefier, I've not taken one apart to check.

And yes, the Edelbrock is a fine carb, but it was designed at least a decade and probably more before the Q-Jet (I had an AFB on a 413 Wedge and it ran great).

The only thing I would argue is that the Q-Jet was built with the lessons learned from the AFB, but the opposite isn't possible. The Q-Jet was designed to emulate the tri-power designs of the day (primaries representing the center carb and the huge secondaries the outboard carb). You can observe that only the Corvette retained tri-power for marketing purposes once the Q-Jet was available. Otherwise they went to Holley (302, LS6, etc).
"You sound like the kind of guy that probably owns and knows how to use a multimeter, hook it up".

Don't need to hook up a multimeter for this install even if I was doing it myself.

So, as stated in longstepper's post, he's running a MSD distributor, and we have determined it's the one in this link that puts out 7.5 amps of energy. So, it's obvious it takes at least that much and probably more to produce that much transformed energy so in regards to this post, you are flat-out wrong to assume he needs less amperage.

So, even by your own words, a stock HEI needs more energy than the points (obviously) and as you are aware of the resistance wire it does not put out 12 volts when the engine is running; HEI needs 12 volts. Now here is an instance when someone who knows how might want to use a multimeter.

http://www.msdignition.com/Products/...stributor.aspx

And yes the ignition switch is not designed to run on the "ragged edge", but that was in 1969 over 40 years ago, and most people like to run a stereo, various chargers, GPS, the list goes on and on, off the fuse block or other accessories that were not around in 1969 so I always advise people to not tap into the ignition switch when they don't have to.

The AFB being designed however earlier than the quadrajet makes absolutely no difference whatsoever in the validity of the design, I don't care if it's 50 years. The only thing the quadrajet actually has over the afb is the adjustability of the secondary air valve, and the AVS, another edelbrock carb, can give you that if you want it.

"Maybe the crank circuit of the ignition switch is significantly beefier, I've not taken one apart to check".

FYI: refer to the 6th illustration on the right hand side of this link to see how an ignition switch works and how the switched voltage all goes through the same circuit and branches off.

http://en.wikipedia.org/wiki/Key_(lock)

davepl: "Why do you believe this"?

mechanical man: All the above, you asked, I answered respectfully.

Bottom line, I'm trying to help this guy, I'm not here to argue with you but if I don't correct this, this guy might keep his HEI wired up to the resistor wire and you will have completely de-railed his install. Or worse yet blow the ignition switch or maybe cause a fire.

If you ever want to dispute what I say, or just like to argue, let's not do it on this forum. You can e-mail me at chrismann1@cox.net
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Old 09-17-2014, 04:36 PM   #13
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Re: 69 chevy feeling tired!

Complete BS. I said nothing about leaving the resistance wire in. I said that breaker points have a resistance wire. I even specified that during the crank cycle this is not the case. So for you to just pick random ideas out of your head, attribute them to me, and then argue their validity is a waste of your, mine, and everyone's time.

Furthermore, stating your opinion (that carburetor technology did not advance for 50 years, which is laughable) as a fact just confuses people even more.

Problem is that I can't debate offline because there's just too much wrong information disseminated here that can cause people grief. OK, I can argue the merits of Q-Jet vs AFB offline, but that actually wasn't the point I was making. If you actually take the time to read, my point was that there was nothing to be gained in switching from one to the other with respect to the issue he's experiencing. I stand by that. Why argue it?

Click on the link you posted about some lock. What good does that do for anyone? It's a broken link to Wikipedia about how keys and locks work. It has nothing to do with the load capacity or contact alignment of a 1960s GM ignition.

Last week it was telling someone he could use his neutral balanc 350 small block flexplate with his externally balanced 454. That'd work real well. I have no idea if it was you but it's the kind of thing that drives me crazy.

For example, I'll grant that if you load up an old truck with electric fans (without relays) and halogen lamps (without relays) and an electric fuel pump (without relays) and big capacitive discharge box you're probably asking too much. So use relays. If you think the change from breaker points to HEI is a material change in the load, don't tell me you're so smart and experienced that you "know" it, take a measurement.

If your intent is to actually help this guy then stop wasting your energy trying to parse and find fault with every piece of information I post. If I make an egregious error, correct it so the OP doesn't get misled. Otherwise, go beat your dog or something because I don't need the abuse and annoyance.

Going forward I'm just going to stay out of threads you're involved in. If someone burns their truck down at least I won't appear on the thread. And it'll save people from listening to us argue.
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Old 09-17-2014, 05:18 PM   #14
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Re: 69 chevy feeling tired!

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Complete BS. I said nothing about leaving the resistance wire in. I said that breaker points have a resistance wire. I even specified that during the crank cycle this is not the case. So for you to just pick random ideas out of your head, attribute them to me, and then argue their validity is a waste of your, mine, and everyone's time.

Furthermore, stating your opinion (that carburetor technology did not advance for 50 years, which is laughable) as a fact just confuses people even more.

Problem is that I can't debate offline because there's just too much wrong information disseminated here that can cause people grief. OK, I can argue the merits of Q-Jet vs AFB offline, but that actually wasn't the point I was making. If you actually take the time to read, my point was that there was nothing to be gained in switching from one to the other with respect to the issue he's experiencing. I stand by that. Why argue it?

Click on the link you posted about some lock. What good does that do for anyone? It's a broken link to Wikipedia about how keys and locks work. It has nothing to do with the load capacity or contact alignment of a 1960s GM ignition.

Last week it was telling someone he could use his neutral balanc 350 small block flexplate with his externally balanced 454. That'd work real well. I have no idea if it was you but it's the kind of thing that drives me crazy.

For example, I'll grant that if you load up an old truck with electric fans (without relays) and halogen lamps (without relays) and an electric fuel pump (without relays) and big capacitive discharge box you're probably asking too much. So use relays. If you think the change from breaker points to HEI is a material change in the load, don't tell me you're so smart and experienced that you "know" it, take a measurement.

If your intent is to actually help this guy then stop wasting your energy trying to parse and find fault with every piece of information I post. If I make an egregious error, correct it so the OP doesn't get misled. Otherwise, go beat your dog or something because I don't need the abuse and annoyance.

Going forward I'm just going to stay out of threads you're involved in. If someone burns their truck down at least I won't appear on the thread. And it'll save people from listening to us argue.
"Going forward I'm just going to stay out of threads you're involved in". Thank you very much for that davepl, and have a nice day. That's a quote I'm going to treasure for a long time.

Last edited by mechanicalman; 09-17-2014 at 05:24 PM.
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Old 09-17-2014, 05:29 PM   #15
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Re: 69 chevy feeling tired!

Keep editing your post, you'll get it right eventually.
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Old 09-17-2014, 05:35 PM   #16
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Re: 69 chevy feeling tired!

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Well a small block with big tires will never be fast, but it sounds like you're comparing it to itself, so probably OK.
What do you mean by that? My 86 k10 on 35's does 0-60 in 6 seconds with a 383 stroker and 4.10 gears. Not super fast but pretty fast for a lifted truck on 35's and still smokes all the ricers. I will be faster once I swap in a more agressive cam and different heads.
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Old 09-17-2014, 05:41 PM   #17
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Re: 69 chevy feeling tired!

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Keep editing your post, you'll get it right eventually.
davepl 9-17-14 @ 01:36pm: "Going forward I'm just going to stay out of threads you're involved in".

You are as good as your word, LOL. Edit on the way LOL.

Edit alert! LOL

Last edited by mechanicalman; 09-17-2014 at 05:41 PM. Reason: Always edit
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Old 09-17-2014, 06:02 PM   #18
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Re: 69 chevy feeling tired!

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What do you mean by that? My 86 k10 on 35's does 0-60 in 6 seconds with a 383 stroker and 4.10 gears. Not super fast but pretty fast for a lifted truck on 35's and still smokes all the ricers. I will be faster once I swap in a more agressive cam and different heads.
Anyway, that's pretty quick for a K10. My Range Rover is heavier still and runs 4.8 0-60 (if you can imagine the Diesel version takes 12.6!). In both cases it takes a lot of torque. Mine's only rated 510hp/461ftlb but must be underrated, because it runs low 13s and weighs 6600lbs w/fuel.

I guess rather than saying they're never going to be quick I should have said "it takes a ton more power because you're working against a tall tire ratio and a heavy truck to begin with".
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Old 09-17-2014, 06:04 PM   #19
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Re: 69 chevy feeling tired!

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davepl 9-17-14 @ 01:36pm: "Going forward I'm just going to stay out of threads you're involved in".

You are as good as your word, LOL. Edit on the way LOL.

Edit alert! LOL
Going Forward == Future
Presently == Right now
Looking Back == Past

ROTFLOLPMP!

As flattered as I am that you're obsessed with me, keep it related to trucks please.
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Old 09-17-2014, 06:08 PM   #20
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Re: 69 chevy feeling tired!

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Anyway, that's pretty quick for a K10. My Range Rover is heavier still and runs 4.8 0-60 (if you can imagine the Diesel version takes 12.6!). In both cases it takes a lot of torque. Mine's only rated 510hp/461ftlb but must be underrated, because it runs low 13s and weighs 6600lbs w/fuel.

I guess rather than saying they're never going to be quick I should have said "it takes a ton more power because you're working against a tall tire ratio and a heavy truck to begin with".
I would say it is underrated. My 383 stroker is putting out 450hp/470lbft. We have estimated it at around 500hp/540 torque with the new cam and heads i am going to put on. That has to wait till this winter though for when i tear the whole truck down and do a full restoration.
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Old 09-17-2014, 06:28 PM   #21
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Re: 69 chevy feeling tired!

Ignore the drama and run a 10 gauge wire from your ignition unfused plug in your fuse panel to the HEI...and gap your plugs to what MSD says, should be around .045. Then set your total timing per the timing sticky. You may also have a vacuum leak with all the parts you changed out. Re-torque the carb and intake in the right pattern to the right specs. Plenty of threads on HEI, timing, and vaccum links on this board, got my 71 purring with the same upgrades.
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Old 09-17-2014, 06:32 PM   #22
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Re: 69 chevy feeling tired!

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Ignore the drama and run a 10 gauge wire from your ignition unfused plug in your fuse panel to the HEI
Doing the math 20 gauge would feed HEI just fine, but more doesn't hurt except the price and size of wire you have to run. [Edit: It's actually 22.5 AWG for chassis wiring at 12V]

Keep in mind that the IGN UNFUSED is exactly that. If anything fails on that circuit and melts that line, nothing will run.

If mechanicalman wants to argue this one too, I'd ask that you look up the spec for the fusible link at the horn relay, which is where all of this current has to go anyway. That will give you a decent sense of what that circuit is expected to manage.
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Old 09-17-2014, 06:33 PM   #23
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Re: 69 chevy feeling tired!

BTW, yes, fusible links are inline and they melt when they go.
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Old 09-17-2014, 06:47 PM   #24
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Re: 69 chevy feeling tired!

I probably ran 12ga. unfused to my POS Skip White (that has worked perfectly fine for me over the last year or two)There is a great thread arguing whether to run a fuse inline on an HEI, too.
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Old 09-17-2014, 06:52 PM   #25
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Re: 69 chevy feeling tired!

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Originally Posted by sKnNyPpY View Post
I probably ran 12ga. unfused to my POS Skip White (that has worked perfectly fine for me over the last year or two)There is a great thread arguing whether to run a fuse inline on an HEI, too.
I'd never put a fuse in it. If anything I'd put an auto-reset breaker in it like the headlights have. I use them for fans and anything where I'd like not to be left stranded due to an intermittent overload or short. Clearly if you've got a dead short no amount of breaker or fuse is going to help.

From the factory, as I mentioned, it's just a fusible link.

Quality 12GA (let's say 1.5 ohms per 1000 feet) will max out at 41 amps. It'll hold 197 pounds too if that's useful info :-)
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