Pushrod pinch porting gains???

[Dragonbat13]

I was reading the porting 318 heads sticky, but it doesnt have anything on the pushrod pinch in the intake runner. does anybody have anything to chime in on how much of a gain of flow or power it is worth?

Reason I ask is I just ordered one of those E tools by DR Air and was gonna try it out along with some other porting.

Thanks

 

[Abodybomber]

This a good question.However,we need more info.What.numbers do you want?(h.p.,/e.t?)Are porting heads for a dart ,a cordoba?Inquiring minds need to know

 

[JoeDust451]

I was reading the porting 318 heads sticky, but it doesnt have anything on the pushrod pinch in the intake runner. does anybody have anything to chime in on how much of a gain of flow or power it is worth?

Reason I ask is I just ordered one of those E tools by DR Air and was gonna try it out along with some other porting.

Thanks

1st, what is this E tool your speak of?

About the pushrod pinch, I took about .080" or so off my 906 heads, you may just wnt to raise the roof entrance some too, really don't know the benifits of the PP other then just more flow, basically just giving it more runner volume.

 

[Dragonbat13]

This a good question.However,we need more info.What.numbers do you want?(h.p.,/e.t?)Are porting heads for a dart ,a cordoba?Inquiring minds need to know

I really dont have any numbers to give. I will give an example. This is a plan that I am thinking about but havent committed yet, Although I do have most of the parts for this build already.
* with the parts I already have

72 dart
*904 with 999 gears
2800 convertor(will go up to 3500 if necessary)
3.91 gears
*vacume second carb (not sure what size but probably a 750, DP also possible, but would like the street manners of the VS)
*RPM airgap for magnum (vertical intake bolts)
*1 5/8 headers
10.1 compression
*magnum heads(Questionable See below)
dont know what cam but hyd roller with matching springs and custom length pushrods.(Valve train will be set up as best as possible, not just slamming a cam in and being done with it)
basic porting as done in the porting 318 heads sticky
2.5 inch dual exh. with x pipe
mopar ignition with reworked curve.

Hoping to get 350 to 400 HP. Dont know if this is enough engine.

OH DUH!!!!!!! Gonna be a .30 over 318 Magnum truck motor (5.2, Barrel intake mutt). Zero Deck height to get some quench.

Also all this is going to be done on the magnum heads. If I dont have enough of these heads to get a good pair I will most likely go with the RHS Indy LA X (I think those are the magnum ones, I have to do more research on that one.

I gotta go. I will answer more questions if needed. Thanks

 

[Dragonbat13]

1st, what is this E tool your speaking of?

I dont think they call it an e tool. I dont remember where I got that name from but it was a mag article somewhere. I just wanted to try one out. Here is a link. It is part number PRG20 at the top of the page.

http://mondello.com/pages/catalog_pg25.htm

 

[JoeDust451]

I dont think they call it an e tool. I dont remember where I got that name from but it was a mag article somewhere. I just wanted to try one out. Here is a link. It is part number PRG20 at the top of the page.

http://mondello.com/pages/catalog_pg25.htm

Thanks.

 

[RustyRatRod]

I think it depends on which heads you have. If they are some fore of swirl port castings, I think you can do more harm than good modifying the push rod pinch. Maybe Justin will chime in. He's really sharp on this.

 

[MoparAnglia]

I really dont have any numbers to give. I will give an example. This is a plan that I am thinking about but havent committed yet, Although I do have most of the parts for this build already.
* with the parts I already have

72 dart
*904 with 999 gears
2800 convertor(will go up to 3500 if necessary)
3.91 gears
*vacume second carb (not sure what size but probably a 750, DP also possible, but would like the street manners of the VS)
*RPM airgap for magnum (vertical intake bolts)
*1 5/8 headers
10.1 compression
*magnum heads(Questionable See below)
dont know what cam but hyd roller with matching springs and custom length pushrods.(Valve train will be set up as best as possible, not just slamming a cam in and being done with it)
basic porting as done in the porting 318 heads sticky
2.5 inch dual exh. with x pipe
mopar ignition with reworked curve.

Hoping to get 350 to 400 HP. Dont know if this is enough engine.

OH DUH!!!!!!! Gonna be a .30 over 318 Magnum truck motor (5.2, Barrel intake mutt). Zero Deck height to get some quench.

Also all this is going to be done on the magnum heads. If I dont have enough of these heads to get a good pair I will most likely go with the RHS Indy LA X (I think those are the magnum ones, I have to do more research on that one.

I gotta go. I will answer more questions if needed. Thanks

You want the MA X heads for Magnums.

 

[Dragonbat13]

Yea I wasnt sure on the name of the heads. The MA X heads are what I will use.

 

[1wild&crazyguy]

U wont really pick up much flow 'maybe 3-5 cfm, if any'...the real gains are from working the short turn , bowl, guide, straight wall just above the short turn.
if all u plan on doing is opening the push rod pinch...dont expect any real increase in flow.
even gasket matching by itself is pretty fruitless in comparrison to working the areas i mention above.

the push rod pinch wont become a restriction till ur moving around 250cfm.ime
there is a formula to figure out how much the port window will flow, if ur below that figure...dont waste the effort.

lots of bs tales and misconception when it comes to porting/gasket matching.

 

[Dragonbat13]

For some reason the short turn scares me. I remember when they would say not to even mess with it. I read the porting sticky and looked closely at the SSR part but am still a little confused. Should I make the SSR more of a parallel path with the guide in the bowl, Or should I lower the whole thing, or what? I wish I had a flow bench. I saw a website called diyporting.com that focused on ford heads but they had a home flow bench setup on the site that was for sale, looked kinda promising.

 

[Oldmanmopar]

Unless your welding up the holes and redrilling or have T/A heads and using offset rockers don't waist your time. You wont gain anything worth the effort.

 

[Cudafever]

Heres another DIY flow bench, that i based mine off of.
http://www.flowbenchtech.com/plans.html

My self, i would leave the SSR "aka" short turn into the bowl, alone, until you have a flow bench and a junk head to experiment on.

Most first time porters will destroy the ssr just by the simple fact that inexperience will cause a vary pour shape and destroy the flow, causing lot of turbulence.
Just my opinion.

Just remember this. The smallest part of the port controls the speed and flow of the head. that big old bump from the push rod is not the restriction you my think it is.

 

[Marcelo Dart BR]

Just smoothing the ssr is a good idea?

 

[1wild&crazyguy]

shape the guide, blend/smooth factory angles just off the seat and call it good.

do not completely flatten the angles, just smooth/round them.

the restrictions are between the guide and short turn for the most part.

 

[D-mailman]

Yes..the tool is the Helgusen 'E' tool because it looks like a capital letter E. It works VERY well. I use mine on EVERY job I do. It accurately measures the wall thinkness in the pushrod pinch. On factory castings, be careful on the short turn..there is water there. You want to widen the port at the short turn and creat a 'D' shape. That will pickup the flow like gang busters at higher lifts. The port won't stall @ .550 lift as is the case with the small Mopar factory head castings. The reason for the port stalling early is because of the narrow port in that area. Good luck.
Terry