Ever start an engine without headers ??

[michel schryer]

I'm close to fire up my engine but I'm missing my headers and sidepipes,i have to get them ceramic coated this week.
A guy at work that is building a Coupe from FFR said,c'mon just put gas and fire it up ! Anybody ever fired an engine naked,no headers,no pipes. Besides the noise,is there any problems with that? I want to wait for my pipes but i'm exited to fire it up,should I wait ? I don't want to freak out everybody.
Cheers !

Michel

[onefastmustang]

I wouldn't do it.. At least not with lots of fire suppression handy. I have seen flames shoot out of motors from doing that. What's nearby you want to fry.. LOL

[jwd]

I've bought several motors from wrecking yards over the years and that's the only way to tell if they run and don't have any knocking. Go for it. There's no down side.

Jim

[michel schryer]

No downsides ? mmmm,sounds tempting!

Thanks guys !

[puppster]

I have been told that you run the risk of doing damage from extra heat due to more O2 being available to the fire. I guess you could possibly burn a valve or something. I did do this with my father 20 some years ago with a junk yard motor on the garage floor. It's quite a site for sure.

[Silverback51]

If it's a new engine, I would not do it. You will not be able to hear if there are any noises.

[onefastmustang]

I am just considering the surrounding area... Ya know.. Fiberglass, wiring... Stuff that doesn't like flame. Other than that I suppose a short term run would be fine.. Although with the lack of backpressure I bet it runs less than optimally.

[kobrabytes]

This is the info I found:

"Running your engine without a pipe is not smart. Your engine is not running properly no matter what your temps are. It lacks the proper amount of backpressure that the pipe provides, plus it is extremely vulnerable to dirt and debris getting into the engine via the exhaust chamber."

[lineslinger]

I saw two guys fire one up in a gravel driveway sitting on the oil pan at night, just like going to the circus and the 4th of July on the same night.

[cobraviper_99]

I recently had my headers and side exhausts off to have the coating reapplied. I started the engine and the flames coming out of the engine were pretty intense. I shut it off immediately. Running it much longer probably would have damaged the paint on the lower fenders.

[jdean]

It will burn the exhaust valves if you run it naked for very long.

[Rick Parker]

jdean speaks the truth..........

[tcrist]

You could also warp the valves. The cold air sucking into a hot exhaust port is not good.

Terry

[xlr8or]

yep bad idea but those big blue flames are pretty cool.

[Double Venom]

No down sides!?

There are some good points here, burning valves is almost a promise, warping a valve stem falls right in line. Damaging the car? Well not likely but entirely possible!

I really like the comment about "hearing" a problem, i.e.; rockers not set right, collapsed lifter, bad bearing, timing to far advanced/retarded, and the llst goes on and on

Especially new motors need at least 21 inches of exhaust on all ports to keep from damaging the engine. Just an ol' tuners 2-cents worth!

DV

[twin turbo]

No down sides, that is funny. I would absolutely wait till you get your exhaust system on. Cheers.

[jwd]

Originally Posted by Double Venom

No down sides!?

There are some good points here, burning valves is almost a promise, warping a valve stem falls right in line. Damaging the car? Well not likely but entirely possible!

I really like the comment about "hearing" a problem, i.e.; rockers not set right, collapsed lifter, bad bearing, timing to far advanced/retarded, and the llst goes on and on

Especially new motors need at least 21 inches of exhaust on all ports to keep from damaging the engine. Just an ol' tuners 2-cents worth!

DV

The old "burnt valve" scare is an old wives tale from the model T days. I don't buy it and never have. Neither do most builders. Drag racers don't have a problem with burnt valves and they run them as hard as possible and then just shut em off.
My comment about hearing a problem was referring to a rod, piston or wrist pin knocking, which you can hear just fine, not a lifter ticking.
I wasn't thinking about the OP having the body mounted though. I definately wouldn't do it with a fiberglass body that close to the exhaust ports.

Jim

[cobraviper_99]

My car has an aluminum body. The inner fender area was getting a tad warm.

[tcrist]

Originally Posted by jwd

The old "burnt valve" scare is an old wives tale from the model T days. I don't buy it and never have. Neither do most builders. Drag racers don't have a problem with burnt valves and they run them as hard as possible and then just shut em off.
My comment about hearing a problem was referring to a rod, piston or wrist pin knocking, which you can hear just fine, not a lifter ticking.
I wasn't thinking about the OP having the body mounted though. I definately wouldn't do it with a fiberglass body that close to the exhaust ports.

Jim

Drag racers run headers. They dont just run them without any exhaust on them. That is what the orgional poster was talking about.

Terry

[Excaliber]

Well it appears that old wives tale about the "need for backpressure" is still alive and well. You need backpressure on your exhaust like a muffler needs a new bearing...