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Discussion Starter #1
id like to create more vacuum in my engine....does anyone think a vacuum pump from a diesel pickup engine would do the job? i only ask because a racing pump is so expensive?
 

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Pro Gas Jet
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Smog pump

I know a guy that builds serious power with junk yard parts. He would turn old smog pumps into vacuum pumps. Its definitely an option. we put a vacuum gauge on the motor with a check valve on it so you can see what ur max vacuum was on a pass. works great.
 

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"Need For Speed"
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id like to create more vacuum in my engine....does anyone think a vacuum pump from a diesel pickup engine would do the job? i only ask because a racing pump is so expensive?
You may want to check a salvage yard for a "smog" pump. Prior ot Moroso and others manufacturing race vacuum pumps, racers were using "smog" pumps. The first vaccum pump I used on my Competition Eliminator engine back in the early '90's was a smog pump from a Ford pickup.

Gear
 

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Discussion Starter #4
i have a niebor with a wrecked 88 f250 and the vac pmp was already sitink on the fender so it made me think and it would be free. woud a smog pump be better than a vacuum pump?
 

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Resident Ford Nut
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i have a niebor with a wrecked 88 f250 and the vac pmp was already sitink on the fender so it made me think and it would be free. woud a smog pump be better than a vacuum pump?
Does your engine have excessive blow-by? Is it a fresh build ....and why do you want more vacuum? what rpm range do you run it?

S CP :)bulb
 

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I had seen some of the late 90's cars (GM, I think) had an electric smog pump. Pretty serious duty cycle and could probably be had pretty cheap. No belt and no bracket:)
 

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Vacuum pump

There exists a certain Delco smog pump that is a heavy duty belt driven unit and actually has about a 3/4" hose barb on it for connections- years ago, a guy I knew was experimenting with them as blow thru superchargers for Go Kart engines. He was getting them from salvage yards. Seems I recall that there was a forum post on the web about go kart supercharging that listed a part number for the desirable pump. I know also that my 94 Camaro HAD a smaller electric smog pump on it- a couple of those- one on each side- may do the job, however they will probably pull quite a few amps if you really get them doing some work.
 

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Late model Corvettes offer an electric pump that is set 6-7 lbs works well and cheap too!
 

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A couple quick related questions. Are there any drawbacks...seems like a while back over on the dyno they were discusing how it could create oiling issues. I could be way off but seems like they were talking about starving the wrist pins. Secondly....don't you need special rings to take advantage of the vacuum?....or would any motor benefit?
 

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Discussion Starter #11
on my first build last yr i was getting alot of blowby in the rocker covers. tore that engine apart and am assymbling a different one. i just want to head off the problems before they are problems. I run 3-5k last yr. hope to get more revs this yr. I had read that with the big cam and tunnel ram there are vacuum issues......
 

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Resident Ford Nut
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on my first build last yr i was getting alot of blowby in the rocker covers. tore that engine apart and am assymbling a different one. i just want to head off the problems before they are problems. I run 3-5k last yr. hope to get more revs this yr. I had read that with the big cam and tunnel ram there are vacuum issues......

this is why it's a good idea to ask a few questions before offering up advice.

FYI, on your engine these are seperate issues, but I'll let someone smarter than me answer them.

S CP
 

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To answer what i think the op was really asking...Tunnel ram/big cam=less vacuum. Are you having issues with the power brakes? lol

Vacuum pumps on a diesel is to generate vacuum for accessories and power assist brakes.

Aftermarket vacum pumps/smog pumps are used to generate negative pressure in the crankcase to reduce friction.

Yours is just a tune issue, poor idle quality, crappy throttle response from low rpm. Mine makes 4-5" @ idle in gear.

Blowby in the rockers is a function of how well the rings seal, all motors do it.
Normal blowby is addressed with a proper crankcase ventilation system.
 

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on my first build last yr i was getting alot of blowby in the rocker covers. tore that engine apart and am assymbling a different one. i just want to head off the problems before they are problems. I run 3-5k last yr. hope to get more revs this yr. I had read that with the big cam and tunnel ram there are vacuum issues......
Huge difference between manifold vacuum with a T ram, and crank case vacuum. Carbs and manifolds have nothing to do with crankcase vacuum.



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Huge difference between manifold vacuum with a T ram, and crank case vacuum. Carbs and manifolds have nothing to do with crankcase vacuum.
But you can hook them together with a hose and a metered check valve, right?:)
 

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mo balls than $cents$
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But you can hook them together with a hose and a metered check valve, right?:)
Lol yep a pcv valve.the electric smog pumps that came on sime f & y body cars works good even s10's had it for awhile and they pull 5-6hg on the inlet side..not sure how long itd take to pull a bbc crankcase into vaccuum at wfo tho, thats alot of volume.i know ls guys use them successfully but ls doesnt have much of a blowby issues.mine has big ring gaps(blown race specs) and i have no need to crankcase evacuation really.never leaks oil or builds much pressure.
guess someone cld use a msd rpm switch to turn on a electric smog pump over a predetermined rpm level.
 

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The electric idea does have potential....The only time pan vacuum makes a difference would be WOT and for less than 10 seconds at a time...Hook up a couple..or more for max suck...No hp loss like a belt drive deal.
The drag comes in the form of alternator 'refilling' the battery while putting around.
Given the amount of hp increase available if 2 of them used up 10 hp worth of drag on the alternator but freed up 20 hp......
Or how about hooking the inlet for a supercharger to pull from the pan....
 

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An engines crankcase must be vented or it will build pressure and develop leaks....not to mention all the crap from blow by contaminating and diluting the oil. A race engine (that is built specifically for a vacuum set up) is a whole different animal from anything that is not a flat out race engine. All any other engine needs is a crankcase evacuation set up like either a PCV valve (not recommended for an engine that will get used hard because the oil vapor that's introduced into the intake makes the engine detonation prone) or (preferred on a non smog compliant engine) a header evac system. I run a header evac set up on my 634 horse BBF jet and it works flawlessly with a (fresh air inlet) breather in the front of each valve cover.
Rob
 

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The problem with the F-body electric EGR vacuum pumps is oil. They do not last long when the oil mist gets to them. I used one on my Rebel for a while. I had a micro switch wired to a relay so the pump only ran at WOT. Some of the Grand National (Turbo v6 car, not boat) guys have been somewhat successful using them but IMO they are not a good solution. I had much better luck with header evacs.
 
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