RPM Airgap

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Hydraulic lifters have a lot of take-up space. since you aren't complaining about lifter pump up, things must be close enough between the min/max of the lifters. It might not be the best idea, but it seems to be working for you.I sure wouldn't lose sleep over it yet.

According to post#24, you are pretty happy with the engine, so why are you fussing with intakes? Just asking..

An easy way I have found to compare pushrod length is to line them up all side by side,on a flat surface, then slide a straight bar up underneath the tips at about 90* to the shafts. Then the other end will tell the story. Sometimes a second straight edge can be helpful.Their average length can be found by measuring between the bars.This method is quick,easy, and allows you to keep them in order.
 
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Hydraulic lifters have a lot of take-up space. since you aren't complaining about lifter pump up, things must be close enough between the min/max of the lifters. It might not be the best idea, but it seems to be working for you.I sure wouldn't lose sleep over it yet.

According to post#24, you are pretty happy with the engine, so why are you fussing with intakes? Just asking..

An easy way I have found to compare pushrod length is to line them up all side by side,on a flat surface, then slide a straight bar up underneath the tips at about 90* to the shafts. Then the other end will tell the story. Sometimes a second straight edge can be helpful.Their average length can be found by measuring between the bars.This method is quick,easy, and allows you to keep them in order.[/QUOTE

I am pretty happy with the engine but I am always looking to make things better and I believe the air gap will be a better intake than the old holly dominator single plane intake.

Now while not knowing the cam size and some other unknown stuff I can't say 100% it will be a better intake but I believe it will.

I am slowly getting things done that will allow me to know all the aspects of my car and engine.

Thanks Don
 
so i took out the intake gaskets and took off the silicone from the front and rear and put bolts in one side and not the other to see what i was looking at for fitment. There is no real big gaps for the intake/head mating surface so i don't think its hitting on the bottom of the intake and the angles and ports seem to be pretty much in line

with no gaskets and one side bolted down the bolt holes on the other side seem to be about half off. Could it be the heads are the ones ( newer or older i dont remember)that require a different angle of the holes.

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That's goofy.
Your intake is not sitting down far enough. Ima guessing it's sitting on those little sticky-out thingies on the ends of the head gasket that line up the intake gaskets and clamp down the end seals. Cut them off and try again. The intake must drop down into the valley and both sides must contact the both heads,and it must not slide transversely on the china-walls.
 
That's goofy.
Your intake is not sitting down far enough. Ima guessing it's sitting on those little sticky-out thingies on the ends of the head gasket that line up the intake gaskets and clamp down the end seals. Cut them off and try again. The intake must drop down into the valley and both sides must contact the both heads,and it must not slide transversely on the china-walls.


Thank you


I took the tabs off and it made it a little better when the intake is sitting on there not tightened down at all it sits pretty flat on the head but still not enough to get the holes on each side to line up at the same time. And when i tighten the one side down the hole alignment gets a bit worse.
 
You need to machine the thickness of the gasket, plus .020 from the sides of the intake manifold. Then take .040 or so off the end rails of the manifold.

Cutting the intake manifold to make it fit does not render it useless on any other application. Make it correct for now by machining it to fit.
 
Cutting the intake manifold to make it fit does not render it useless on any other application. Make it correct for now by machining it to fit.

Exactly. I bought a Performer RPM that had been milled .040 knowing I really needed an intake with stock dimensions. One call to Cometic got me a set of custom .094" thick gaskets delivered for $30
 
You need to machine the thickness of the gasket, plus .020 from the sides of the intake manifold. Then take .040 or so off the end rails of the manifold.

Cutting the intake manifold to make it fit does not render it useless on any other application. Make it correct for now by machining it to fit.

Thanks I was not thinking of extra thick gaskets for other applications down the road.
 
You need to machine the thickness of the gasket, plus .020 from the sides of the intake manifold. Then take .040 or so off the end rails of the manifold.

Cutting the intake manifold to make it fit does not render it useless on any other application. Make it correct for now by machining it to fit.

So if my gaskets are .060 I should go .080 And about .040 on the front and rear rails.

The machine shop wants 200.00 to do the work and I've Already got 325.00 wrapped up in the intake and gaskets ughh

Thanks Don
 
So if my gaskets are .060 I should go .080 And about .040 on the front and rear rails.

The machine shop wants 200.00 to do the work and I've Already got 325.00 wrapped up in the intake and gaskets ughh

Thanks Don

Yup. There is no such thing as "bolt on" and never has been.

But there damn sure is a thing called tolerance stack up. Seems you and tolerance stack up have now met personally.

Keep us posted.

BTW and FWIW that's pretty close to what I figured the machine work would cost. You are paying for 4 set ups. The actual machine time is about 20 minutes!
 
with no gaskets the bolt holes are pretty far off. I don't know how someone can look at a picture and say .020" will do it (plus gasket)
 
with no gaskets the bolt holes are pretty far off. I don't know how someone can look at a picture and say .020" will do it (plus gasket)

It's called having these issues in the past first hand. You also have to remember his gaskets are .060 thick and there are .045 and .030 thick intake gaskets available if removing .080 isn't enough. Without knowing exactly how much milling was done to the heads this matter requires an educated estimate. .080 seems about right from my experience also. I've had heads milled myself in the past where a .060 intake gasket resulted in the holes being off by the same amount as his are without gaskets. I was able to use .045 gaskets but a .040 would have probably been a the ideal choice.
 
i talked to the machine shop an they said that its prob not as sbad as it looks in the picture because when its off and you put bolts in just one side and tighten them down it pulls to that side and up so it is skewed to an extent.

he said they have done a lot of them and to put it on there with no gaskets and just get it centered and sitting flat on the heads and see what it looks like and the holes were about 1/8-1/4 off on each side.
 
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So if my gaskets are .060 I should go .080 And about .040 on the front and rear rails.

The machine shop wants 200.00 to do the work and I've Already got 325.00 wrapped up in the intake and gaskets ughh

Thanks Don

$200 to mill an intake! Wow! I'd be finding a new machine shop. Mine did one for me a couple yrs ago for $50
 
Should only be 3 setups. I understand time is money but if your good it shouldn't take more than an hour to do it.

I did find a different recommended shop that was not that expensive. They both charge by the hour but the first one was crazy on shop supplies and what not. I could see if it was an old dirty intake that needed cleaning but its brand new.
 
Well it's done. I took .080 off each side and .040 off front and rear and it was perfect fit after and the shop only charged me $80.00.

Pay no mind to the rest of the wire mess and clutter I still have much more work to do under there. Of course I had to deal with throttle and kick down linkage as well because of the height difference in the intakes.

I originally bought a lokar knock off before I searched the reviews and it sucked just like everybody says. The biggest problem with it is that there us no stiff inner lining under the steal braided mesh and it kinked where it came out of the firewall Esp the quick turn it has to make to get around the valve cover.

I tried some other stuff but with no welder it was near impossible to make things that would work and not look all cobbled up. I went to the local advanced auto and they had a mr gasket universal throttle cable that worked perfect. It attached onto the gas pedal bracket exactly like the original and hooked up perfect at the carb when used with there throttle cable bracket. After some drive and test I took The kick down and just for now affixed it in one position in the old throttle cable bracket so it would allow the trans to shift properly.

I will add pics and part numbers for the mister gasket stuff.
 
and then got her all cleaned up and covered up to keep the damn pollen off. I suppose i could clean the garage and put her in there but that would be to simple lol plus i would have to move out the lawn mower and 4 wheeler


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Well it's done. I took .080 off each side and .040 off front and rear and it was perfect fit after and the shop only charged me $80.00.
1970-dart,
So how did the fit testing go at the machine shop? Did they do it or did you just tell them how much you wanted milled off and where?
Thanks, Richard
 
1970-dart,
So how did the fit testing go at the machine shop? Did they do it or did you just tell them how much you wanted milled off and where?
Thanks, Richard

I just went with the recommendation here ( i believe 80 off each side and 40 off front and rear)and prayed it was close. but it was spot on and worked perfectly
 
Did you get the transmission kick down linkage hooked up?
 
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