Engine air cleaner upgrade.

[shadow]

I know we have a mechanical issues section, but I didn`t feel this belonged there.

In no way is an rv a performance vehicle, it is built to get from point A to point B, camp, have a good
time, and return home. (lets not forget full timers also) Most of us here have older rv`s, and a lot of these
rv`s have big block engines, whether it be a big block ford, chevy, or dodge, does not matter

There are two things you can do to help your rv run better, and probably pick up a few miles per gallon in the process.
The first thing to do is replace the factory air cleaner assembly, it is very restrictive and will not allow your engine to
breathe freely as it needs to.

The seconds thing to do is the exhaust, and I`m not talking about adding headers or anything like that.
A good exhaust from the Y-collector back to a good free flowing muffler is a huge improvement over
the factory exhaust.

My rv is on a 1984 E350 chassis, with a 460 engine.
Today I replaced the very restrictive factory air cleaner, you can see very clearly how restrictive it is, and there is
no way a 460 engine can properly breathe with this factory air cleaner on the engine.


This little tiny hole is the only place the engine can get air from, and it is not even close to big enough, so the
engine is starving for air.


This is the new air filter assembly I installed today, it should make quite a difference.



I probably won`t get the exhaust done until next summer.

 

[SternWake]

How much bigger is the opening down through your carb/ throttle body than the opening on the old air filter housing?

I'd prefer my engine suck up cold/cool air from the tube which leads to the front of the vehicle rather than suck up hot underhood air.

 

[shadow]

How much bigger is the opening down through your carb/ throttle body than the opening on the old air filter housing?

I'd prefer my engine suck up cold/cool air from the tube which leads to the front of the vehicle rather than suck up hot underhood air.

My engine has a Holly carb on it, and its about a third or more bigger than the opening on the stock air cleaner.
And just because an engine sucks in cold air from the front of the engine doesn`t mean its cold when it enters the engine,
because in most cases its not.

 

[Gary68]

i'm planing to source or build a breather tube so it's not sucking in all that hot air under the doghouse

 

[Weight]

When I had my shop, Chevy had a fix for the 327's of turning the lid over on the air cleaner. some time late 60's.

 

[sushidog]

My engine has a Holly carb on it, and its about a third or more bigger than the opening on the stock air cleaner.
And just because an engine sucks in cold air from the front of the engine doesn`t mean its cold when it enters the engine,
because in most cases its not.

I wrapped my Injen cold air intake with insulated foil tape made for this purpose - to minimize engine compartment heat soak.

This is similar to the tape I used, but mine is 3" wide. http://www.ebay.com/itm/DEI-Cool-Ta...ash=item5d719a8148:g:L6kAAOSwHoFXvxHM&vxp=mtr

Chip

 

[jonsun]

Now go get a air/fuel gauge and tune it because you probably just lost a little power doing that.

It's not the exhaust from the y pipe back, it's the manifolds that will give you real power gains from stock...granted you got at least 2 1/2" pipes.

but again if you're opening up air flow you have to also open up fuel flow or you're just leaning the whole thing out.

 

[MrNoodly]

It's not the exhaust from the y pipe back, it's the manifolds that will give you real power gains from stock...granted you got at least 2 1/2" pipes.

Speaking of headers, here's an episode of Engine Masters where they did dyno runs on the same engine with stock manifolds and two different types of headers.


And here's one comparing straight pipes vs. x-pipes vs crossovers.

 

[jonsun]

love engine masters, roadkill, etc!

 

[user 423]

And just because an engine sucks in cold air from the front of the engine doesn`t mean its cold when it enters the engine, because in most cases its not.

My 91 Dodge's air intake is all the way up front, even before the rad.

 

[MrNoodly]

In no way is an rv a performance vehicle...

At best, an RV engine is tuned for bottom end torque rather than top end horsepower.

 

[sushidog]

Now go get a air/fuel gauge and tune it because you probably just lost a little power doing that.

It's not the exhaust from the y pipe back, it's the manifolds that will give you real power gains from stock...granted you got at least 2 1/2" pipes.

but again if you're opening up air flow you have to also open up fuel flow or you're just leaning the whole thing out.

I also installed a shorty header that I port matched to the head and a full Corsa exhaust. Then I sent off for canned tune for both my ECM and TCM from Wester's Garage (telling them about my mods and expectations) they firmed up my tranny shifts (a tow tune), adjusted the shift points, etc. reducing heat and slippage for both my ECM and TCM. I then had it dyno tuned locally to fine tune the AFR. Finally I took it to the track to test my work. Hp went from 171 to 199, but more importantly it raised the torque curve across the entire RPM range, coupled with the tranny tune that allowed me to put more power to the ground I was able to trim .46 sec off my 1/4 mile time. This tranny lasted 300,000 miles and I'm on my second one with 384,000 original miles on the engine.

Chip

 

[shadow]

You don`t really need headers on an rv. A good free flowing exhaust will make a noticeable difference.

 

[GotSmart]

I used those fancy high dollar air cleaners in the 70's.     

Keep a clean filter and let the designers high dollar education do it's thing.  

Shade tree fixes give small returns for large investments.

 

[LoupGarou]

Your going to have engine warm up problems when the temperatures cool.

Put the OEM filter housing back on.

 

[MrNoodly]

No matter how free flowing the intake and exhaust might be, the choke point in the whole system is the valves -- their size, lift and duration. Unless someone is adding forced induction, various upstream and downstream mods are kind of pointless without changing the cam(s) too.

 

[shadow]

There seems to be a lot of people here that are missing the point, or thinking way over the top.

I know what works for me, and have done them many times in the past with great success.
Once I get this all done, I will report back with the results, good or bad.

 

[Willy]

I ditched the paper filter (and rusted up aftermarket housing) of mine for a K&N cotton wire filter. ..Willy.

 

[SternWake]

I ditched my K&N filter and went back to paper after about 10 years, as I found dust inside my throttle body.

I've considered insulating my stock cold air tube, but The air must be moving fast enought that the hot platic tube cannot impart much heat to it.

My Aircleaner has a little diverter valve to suck air heated off the manifolds to aid economy on initial warm up. I could not pass a Smog test without this heat riser tube in place, and this eliminates any open air cleaners, even if I wanted one, which I don't.

My engine rarely goes into the rpm range where the stock filter housing would be restricitve.

 

[MrNoodly]

I ditched the paper filter (and rusted up aftermarket housing) of mine for a K&N cotton wire filter. ..Willy.

Oil particles from K&N filters can collect on mass airflow sensors, throwing the readings off. That's not a problem if you don't have fuel injection, but if you do...