well ive done some work to the motor. mainly boltons. i like to really get on it every once in a while espacially against some ricers. i usually leave it in OD. (700r4) and just floor it. i pull all the way up to around 8000/8500 rpm. then it shifts by itself into second and ill pull to aroun 7000. rpm. and i can countinue to pull after that but usually i have already left the ***** behind. i have tried several tach and am currently runnig a lunar series autometer. to me that seems high in thre rpms but it pulls and never falls on its face,does this sound normal to you all..

 

On anything near resembling a stock motor, 8000+ is WAY past the point of valve float. You would have also friend your engine. Something is way off.

What is all involved with the hookup of one of those tachs.

 

well ive followed the directions. one ground wire, one wire to my interior lights, one wire to the tach feed on the dist. and one wire to my ignition power source. thats what i thought also but the engine runs strong and pulls all the way till it shifts on its own.

 

Make sure the ground wire is properly grounded (the terminal is clean, there is no rust/gunk around or under it, etc).

 

its grounde good i ran the wire through the dash down to the inside fire wall. its hooked up correctly and all wires are making good contact to where they are supposed to.

 

What is the part number and what is the distributor?

 

part number for the tach, jegs part number where i ordered it is 105-4299, as for the dist. its the factory dist with the remote coil. im running an accel cap and rotor. accel extreme 9000 wires and msd blaster coil. i hope thats what you wanted

 

Where are you grounding? Your best ground is directly to the engine block. Aftermarket gauges are far more sensative and require good grounds. I know all of my intellitronix get screwed if i ground to anywhere but the block.

 

there is a fairly large elbow under the dash. about 3 or 4 inches long and 2 or 3 wid. it is all part of the dash steel, frame type thing..it all welded to the front of the cab. i guees you could call it a skeleton of sorts. ive also had it gound to the frame near the front suspension but moved it after i changed to my current tach. im more than positive my ground is good. ive been hookin stereos and amps, subs and stuff up for a while. is it really that starange that i can rev that high.. my brother has an 86 shortbed with a 502 stroker big block and he can run all the way up to almost 9500 rpm before he shifts. but hten again he spent almost 10 grand on his motor

 

I would strongly suggest you (and your brother too) check over your connections again... all of them. There is no way eitheer one of you are reving past 7k rpms and still haven't married your pistons to your valves!

Check to see if there is a setting to change from 4, 6, or 8 cylinders. I also suggest you contact Autometer if you can't figure it out...

 

7K maybe, 9K no way. The tach has to be off somehow. What RPM does is say you're idling at? And at what RPM does it show for a normal light throttle shift?

 

At least one of 2 things is true, maybe both:

Your tach is wrong;
You will be needing a new motor real soon.

The idea of having to wind up a V8 to 8000 RPM just to pass some import is ludicrous. Just because they seem to think that their cars go faster when they tach them out, doesn't mean we have to act ignorant too. Your motor would have no power up there anyway unless you've got alot more than just some bolt-ons, even if it was capable of making it to those RPMs.

Anybody want to start a pool on how long it will be before we see a "My motor knocks" post?

 

i'm guessing you have it set for a 4 or 6 instead of a v8 and i'm sure RB is right

 

ede - Sounds to me like you're both right!

 

 

ok, not a chance in hell your getting 8500 out of that motor, here is why I think that.

1. I'm assuming your talking about the chevy pick up in your avator.

that being said: I had a 88 K5 with the 350 tbi. with an aftermarket tach. I'f I put it in dirve and floored it, it would shift at 4500 every time. I could manually hold it in first all the way to 5300-5500 it made no power at all. none. the motorwould would hit a brick wall, that was it. it more less pooped out around 4800, and above 5 it was a joke. in neutral, wide open the valves would float at 5700-5800. hence max rpm.

ok, as we all know, GM was stingy. every single SBC got the same valve springs, regardless of valve sizes. Unless it was an L98, then it got the better springs. so I think it applies to most sbc of that era.
even if you have an L98, those crap out around 5500-5800 or so. I highly doubt it would rev past 6500 in stock form.

your tach is messed up. probably set on the 4 or 6 cylinder . 8500 is a pipe dream.

 

trying to imagine what my car would sound like at 9k rpms, it already screams pretty loud at 3k heh..
yeah definately sounds like its on the wrong cylinder setting.. little worried about someone who spends 10k on a motor and doesnt understand how to setup the tachometer though..

 

well this will probably be my last post on the subject.yes my tach is set up right. yes it is set on 8 cyl. idling it will be at 800 rpm or so. with the ac on it will go to almost 1000rpm. normal driving it shifts by it self at aroun 4300/4500 from 1st to second. 3900/4200 from secon to drive then it will drop to od. i can be doing 60 and rpms are at 2200 or so. its always run like this and its hard for me to believe that after 3 different tachs they could all be wrong. motors if built properly can pull that high dr1. so just becuz your motor cant see past 5500 or so dont try to talk down on others. if i could figure out how to put my home videos on this computer i could show you how our vehicles actually sound and drive but i dont know how to do that. i understand that this rpm problem sounds strang but i think ill just have to figure this out on my own. thanks to all who did try to help though.

 

Doing bolt ons is not anywhere near building a motor. To reach those RPM's, were talking about complete forged rotating assembly, balanced and blueprinted perfectly, large valve race heads, and a big ol' lumpity lumpity race cam that will give you NOTHING under 5000 rpm.

So in summary, you're not going to get those rev's out of bolt-ons unless your idea of bolt ons is a $20,000 race engine.

My guess is with the other guys. The tach is most likely set on the wrong cylinder selection. If you have an 8 cyl and the tach is set at 4, the reading will be exactly 200% over what it should be. So your 9000 RPM is really only 4500, which is much more like where it actually should be.

Other than that, the only thing that provides your tach signal is the pickup coil and ignition module. The pickup coil fails by cracking the magnet, which provides a weaker signal. The module really only takes the A/C signal from the pickup coil and converts it to square-wave DC, which the ECM can enterprit. I believe that the tach recieves a DC ground pulse from the module, but I could be wrong.

If all else fails, maybe try replacing the module. But I have never heard of one failing by increasing output.

Also, If you have videos of your swirl port TBI truck revving and pulling to 9000 rpm's though, I'd like to see them

Cheers

 

its been 15 minutes now since ive opened this window, i still havent figured out what to write yet..

but seriously somethings broke or setup wrong, i dont know what would cause back and forth readings like that but its not your engine actually doing it. And if it is you could make a fortune teaching the rest of us how to take our 350's to 8500rpms with bolt-ons
drop it in 1st and see how fast you can get to, even with 3.73's you would have to be doing like 50mph to get to 8500

 

 

I dont know, man, if you are to the point of declaring that your stock motor with bolt ons is pulling hard at 8K, then I have no choice but to assume 2 things.

1. You have no idea how cars or engines work.

2. same as #1 and got one hell of a deal on a motor.

There is just no way that you are doing that on a stock motor. I've seen a car that would wind up to 9K or so in the past. Another member here, thegeneral, had it in a 73 split bumper. Nice motor, but it was no where near beign a bolt-on parts kinda motor. This was a serious racing engine.

 

I'm not taking that bet...he'll go straight for a thrown rod before it has a chance to knock. 8K rpm on stock rods and bolts, cast crank...hope he only kills himself and not some innocent bystander.

 

why is it the original question was "does 8000 rpm sounds normal with bolts ons" and when everyone said no the poster got all defensive saying why couldn't it be done?

 

My guess is that we are dealing with someone who just doesnt have any experience in the world of engine building, in or away from thirdgens. I remember when i was in high school kids were talking about how they can pull off 7K without a problem on a stock engine, and it doesnt hurt anything. All i can say is, if you can twist it that high, great do it, just dont bitch when it goes bang.

 

 

You are a goddamned retard.

There isn't a Small Block Chevy ever made that will hit 8k rpm on the stock cam. A 350 TBI with the peanut cam sounds just right for idling at 500 rpm and shifting at 4000, half of what the tach reads. You have it set on 4 cylinders. Tardass.

 

All I have to say to a 9000RPM Shift is

9000 RPM! That is easily 100% over stock. More like four cyl setting on the tach and the engine is shifting at 4500 RPM (stock). I built an Edlebrock RPM engine and that biatch would pull hard all the way to 7000RPM but realllllly wound up tight. That was on a stock two bolt block, stock crank, and stock rods with hypereutectic pistons. Always wondered if it would blow.

 

my 73 split bumper would pull 9k on the tack all day long but we also had about 6 grand worth of goodies in it all internal to make it do that the your first thing is to make sure you have a fully balanced rotating assembly ..lol...a stock one will fly apart in a matter of minutes at those rpms...LMAO...ive done that too..lmao...not a pretty site either..but the 73 camaro we had was a bad s.o.b. and it was by no means stock at all ......
and then i bet there was another 3 grand worth of extenals and exhaust ...

 

yeah, thats kind of a joke. I think somebody needs to quit reading parts catalogs and magazines and start living in the real world.

 

Obviously this guys engine came out of one of Earnhardts Winston Cup cars before he bought it.... I mean, those engine do look and sound just like the stock SBC that comes in thirdgens.... I mean you really couldnt tell from the size headers, intake, heads, idleing at a grand or more, or the fact it has to run on race fuel or it dont move that its not the stock engine.... He does say that It hits 9 grand and the engine is fine.... by my calculations... thats the sweet spot where all the power is. This guy really musta got a good deal on his car. Anyways.... Im sorry dude, but there is no way that your car hits 9 grand unless you have some magical block/crank/rods created out of some metal from the future..... unless its a full out race engine... but thats just silly talk. Heres just a quick question, does your engine say VTEC on the top of it?

 

LOL .....by the time its all said and done to pull 9k rpm your not gonna be streetable anymore ....thats what mine ended up doin anyway ...by the time we were done with it ....we drove it on the street for about a week or two and the cops shut us down really quick..lmao

 

nonsense general, let the boy teach us a lesson. Here is what you do, go and get a tape recorder and put it behind by your car, or a video camara is better. Then start it up and rev it to 9K for us a coupla times. I havent heard the sound of breaking engine in a long time.

 

yeah i think that would be cool man go and do that for us please..LMAO

 

Why the hell doesn't he try a different tach and see for himself? How about the stock one?