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#59230 07/20/10 10:51 PM
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Hey, I'm sure a few of us have read the "Facts" section on Chevy sixes on the Clifford website. They recommend NOT porting, polishing, or port matching on a street head in order to retain velocity. Velocity of the intake charge, I assume, but how are these thing going to reduce port velocity? Less turbulence equals better/faster flow, no? Or is some turbulence desirable for fuel atomization? I've read that too much porting/smoothing can cause fuel puddling in intakes or runners, but all the things they seem to imply go against everything I thought I knew. Any takers?

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By porting & polishing,you are makeing the intake & exhaust ports bigger in volume,therefore you will loose velocity.

I got bogus info from Clifford early on, I stopped taking there adivise a long long time ago.

It was not until I started doing my own things did my car run faster.

You can gasket match the intake port,but I would not go much bigger for street applications.

Installing the intake lumps makes the velocity increase & gives the head a better short turn radius,& that is what you want. ;\)

MBHD


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They also say not to remove the bolt boss or to turbo charge them or use bolt in lumps.

I also disagree with them on those points. They do make good parts that fit and work.

Bigger valves, bolt in lumps and porting will really wake up a chevy 6. Tom

Last edited by tlowe #1716; 07/20/10 11:41 PM.

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They do make nice parts if they would only fit w/out needing to mod them,,,well, correction,,even though I had to return my Weber intake 3 times because it was warped badly I might add.

The cams I used from them are very mild & slow acting cams,OK, if you want to go slow I guess.

Clifford headers needing modding to fit also,plus needed to mod intake manifolds to fit correctly,so over all ,for the most part,I had to mod there parts just to get them to fit on my engines.

These were Clifford headers,Clifford parts period,most don't fit IMO, @ least that my personal experience w/there stuff.

Including there 2 peice timing cover. Had problems that also.

MBHD


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Got it, thanks.

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 Originally Posted By: Mean buzzen half dozen A.K.A. Hank
They do make nice parts if they would only fit w/out needing to mod them,,,..............

Clifford headers needing modding to fit also,plus needed to mod intake manifolds to fit correctly,so over all ,for the most part,I had to mod there parts just to get them to fit on my engines.

These were Clifford headers,Clifford parts period,most don't fit IMO, @ least that my personal experience w/there stuff. MBHD


Hank,

Not sure how old your Cliffy parts are, but my intake & header were purchased about 6 years ago and they fit quite well. I have heard from others that since Jack died the quality has slipped, but I cannot confirm this.


Just my 2 cents worth.

Paul


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I got my parts when he was alive.
IIRC,
Power steering bracket needs modding to fit headers & so-on.

You would think the buying aftermarket intake manifolds for SBC's will just bolt right on,well, some of those need a little help to fit also,the mounting holes,off just enough so the bolts won't start etc.

Just has to do with Q.C.

Main thing I was really mad about was sending the 3 side draft Weber intakes I bought from them,one was warped as much as .060 + or was it .080?

It made me & my friend think they were getting heat treated after they were machined.

MBHD

 Originally Posted By: McGoo
 Originally Posted By: Mean buzzen half dozen A.K.A. Hank
They do make nice parts if they would only fit w/out needing to mod them,,,..............

Clifford headers needing modding to fit also,plus needed to mod intake manifolds to fit correctly,so over all ,for the most part,I had to mod there parts just to get them to fit on my engines.

These were Clifford headers,Clifford parts period,most don't fit IMO, @ least that my personal experience w/there stuff. MBHD


Hank,

Not sure how old your Cliffy parts are, but my intake & header were purchased about 6 years ago and they fit quite well. I have heard from others that since Jack died the quality has slipped, but I cannot confirm this.


Just my 2 cents worth.

Paul


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they were getting heat treated after they were machined

I don't know which is worse: that they don't know (that this can't be done(, or that they don't care.

There are definite differences between manufacturers as to QC - Edelbrock is like jewelry compared to Offenhauser, Weiand somewhere in the middle.
Casting flaws, holes not centered in bosses, flashing not removed, rough gasket surfaces, threads not fully tapped, not thoroughly clean before shipping, etc.
You can also see differences in the quality of the mold itself - both interior and exterior surfaces like concrete, height of runners varies, plenum not centered.
Also differences in development - like mixture bias (Edelbrock works those out as the model progresses, Offenhauser doesn't seem to change it once the money is invested).

Don't assume that anything except OEM bolts on - if that.

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 Originally Posted By: panic
I don't know which is worse: that they don't know (that this can't be done(, or that they don't care.

There are definite differences between manufacturers as to QC - Edelbrock is like jewelry compared to Offenhauser, Weiand somewhere in the middle.
Casting flaws, holes not centered in bosses, flashing not removed, rough gasket surfaces, threads not fully tapped, not thoroughly clean before shipping, etc.
You can also see differences in the quality of the mold itself - both interior and exterior surfaces like concrete, height of runners varies, plenum not centered.
Also differences in development - like mixture bias (Edelbrock works those out as the model progresses, Offenhauser doesn't seem to change it once the money is invested).

Don't assume that anything except OEM bolts on - if that.


My feelings exactly,X2!

MBHD


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After joining Inliners and getting a 292, last christmas I got a bunch of six cylinder hop-up stuff. Tom's lumps, Langdon's side plates, and a neat looking finned alum valve cover from Clifford (with "Chevrolet" script, its a 2-holer for '53ish motor-needs adapter to 292). Sure enough when placed on a flat surface, it acts like a Cracker Barrel rocking chair. All the rest of the stuff worked fine- but not the $250 valve Cover- it would take about .100 to .125 out of the middle to get it to lay flat and that would just about take out the sealing lip on the bottom. Maybe it was machined too soon after casting, and not aged long enough (if that applies to alum castings). Not favorably impressed. But heck, what do Hudson folks know about valve covers!

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Triple bummer. Nobody likes the Offy, Clifford sux(apparently), and the adapter for a 235 cover looks like the only way to go(?).Is there a reliable source out there for a second series chevy 6 valve cover that doesn't suck?

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Forgot to add, my new polished Offy valve cover was totally warped.
I had milled as much as I could to try & get the gasket surface straight as I could,the material got thin,so I could not mill it completely flat.

Initially I had to triple up on the valve cover gaskets to seal it.

MBHD


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Has anyone ever contacted the makers of these products? Once you start bitching real loud, someone usually takes notice...

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I have recently used , new Clifford VC, timing cover and Intake.

The Intake needed slight trimming against a header flange, no pipe rubs. The timing cover needed a slight fit to water pump. And the VC was a true bolt on. The earlier reference to cliffords VC in this thread was a 235 cover.

I use a mercruiser VC on my motor, it fits like a OEM part. The Clifford has room for goodies underneath though. Tom


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 Originally Posted By: vanherk1
Has anyone ever contacted the makers of these products? Once you start bitching real loud, someone usually takes notice...


I sent back my 3 warped Weber intakes & talked w/them(Clifford) each time I sent it back.

The 3rd one I settled for stilled needed .015"-.020" milling.

MBHD


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 Originally Posted By: tlowe #1716
I have recently used , new Clifford VC, timing cover and Intake.

The Intake needed slight trimming against a header flange, no pipe rubs. The timing cover needed a slight fit to water pump. And the VC was a true bolt on. The earlier reference to cliffords VC in this thread was a 235 cover.

I use a mercruiser VC on my motor, it fits like a OEM part. The Clifford has room for goodies underneath though. Tom

How did the timing cover fit and work out, I've been looking at it but I'm a bit worrried about the crank seal fit.


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You need to use a V-8 damper,other than that,mine worked fine.

Or, if you want to use the stock damper,you would need to mill groves it it to clear the V-belt like I did initially.
Also,need to counter sink a few screws.

I can post a pic if you like.Mind you,,,I initially used a grinder to cut the cover for the clearance needed,so it's not pretty & I was young ,with not much skills or access to a mill @ 18 -20 years old LOL. \:D

MBHD


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I would like to see that photo. Love the hacked up sh*t. Not that I'm a hack, of course, but it makes me think of cutting up pristine 56 Pontiac fenderwells when I was 16, in order to use the headers a buddy gave me.

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Anyone have a spare Mercruiser VC?

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 Originally Posted By: Mean buzzen half dozen A.K.A. Hank
Forgot to add, my new polished Offy valve cover was totally warped.
I had milled as much as I could to try & get the gasket surface straight as I could,the material got thin,so I could not mill it completely flat.

Initially I had to triple up on the valve cover gaskets to seal it.

MBHD


I hear you and thats why I made the no name no fin valve cover....


Tom
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