Porting the Edelbrock Pro Flow XT 7137

the more you get into this hobby the more you realize, that theres a vast amount of modifications,
that you could do to improve performance or adapt components designed for a slightly different application,
to match your unique needs, and its only your skill with some basic tools like a drill press,
a decent quality welder, mill or lathe and your imagination, or lack of skills and tools
that prevents you from making a great many modifications or improvements.
most of us learn from making mistakes,
smart people learn from both watching other people make mistake's and doing a bit of research,
and looking for the results ,
and methods that the most successful people have developed,
rather than trying to make their own mistakes.
there's no sense in trying to re-invent something others have previously done and gotten great results, smart people start with a well proven product or well documented plan, then try to make improvements from a known successful combo.

if you look closely at the mods that were made posted in the post above he basically drilled and in some cases threaded several holes,
in two aluminum plates to adapt the older twin throttle body and throttle bracket to the newer plenum.
I doubt you.ll have a hard time locating the materials required,
if your willing to do a internet search of metal supplys near you or on e-bay,
so its simply the lack of skill and tools preventing most guys from doing similar things


my dad always stated..

"A couple hours , well spent in doing carefully documented &,detailed research,
before.... jumping head first off the dock,
into any project,....can prevent you from wasting month's of non-productive work and a wheel barrow full of cash!!"




related threads

http://garage.grumpysperformance.co...op-needs-a-decent-drill-press.970/#post-50726


http://garage.grumpysperformance.co...hine-tools-like-a-mill-lathe.8340/#post-29987

http://garage.grumpysperformance.co...luid-chip-filter-for-my-mill.6093/#post-18813

http://garage.grumpysperformance.co...and-lathe-info-you-might-need.2198/#post-8396

http://garage.grumpysperformance.co...ome-help-me-out-here-gentelmen.993/#post-4129


MATERIALS COST well under THE COST YOU MIGHT EXPECT

its the tools and knowledge that costs you, you could get a quote from a machine shop for $500
and if you have the tooling build it for well less than 1/2 that
btw these linked on-line prices are far higher than many local metal supply stores.. measure very accurately, do the required math and shop carefully

13cal.jpg


17903.jpg

ticalcx1.jpg

https://www.onlinemetals.com/merchant.cfm?pid=1249&step=4&showunits=inches&id=76&top_cat=60

https://www.onlinemetals.com/merchant.cfm?pid=14499&step=4&showunits=inches&id=1268&top_cat=0
custom%20stealth%20ram%201a.bmp
 
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the more you get into this hobby the more you realize, that theres a vast amount of modifications,
that you could do to improve performance or adapt components designed for a slightly different application,
to match your unique needs, and its only your skill with some basic tools like a drill press,
a decent quality welder, mill or lathe and your imagination, or lack of skills and tools
that prevents you from making a great many modifications or improvements.

if you look closely at the mods that were made posted in the post above he basically drilled and in some cases threaded several holes,
in two aluminum plates to adapt the older twin throttle body and throttle bracket to the newer plenum.
I doubt you.ll have a hard time locating the materials required,
if your willing to do a internet search of metal supplys near you or on e-bay,
so its simply the lack of skill and tools preventing most guys from doing similar things


my dad always stated..

"A couple hours , well spent in doing carefully documented &,detailed research,
before.... jumping head first off the dock,
into any project,....can prevent you from wasting month's of non-productive work and a wheel barrow full of cash!!"




related threads

http://garage.grumpysperformance.co...op-needs-a-decent-drill-press.970/#post-50726


http://garage.grumpysperformance.co...hine-tools-like-a-mill-lathe.8340/#post-29987

http://garage.grumpysperformance.co...luid-chip-filter-for-my-mill.6093/#post-18813

http://garage.grumpysperformance.co...and-lathe-info-you-might-need.2198/#post-8396

http://garage.grumpysperformance.co...ome-help-me-out-here-gentelmen.993/#post-4129


MATERIALS COST well under THE COST YOU MIGHT EXPECT

its the tools and knowledge that costs you, you could get a quote from a machine shop for $500
and if you have the tooling build it for well less than 1/2 that
btw these linked on-line prices are far higher than many local metal supply stores.. measure very accurately, do the required math and shop carefully

13cal.jpg


17903.jpg

ticalcx1.jpg

https://www.onlinemetals.com/merchant.cfm?pid=1249&step=4&showunits=inches&id=76&top_cat=60

https://www.onlinemetals.com/merchant.cfm?pid=14499&step=4&showunits=inches&id=1268&top_cat=0
custom%20stealth%20ram%201a.bmp

Amen to that!

Just picked up a piece of 1" aluminum plate from Newberg Steel and Fabrication, $28. This, with some care and time, will become my TB adapter. I also talked to the TIG welder there about my plans to cut the top off the plenum for porting and having him weld it back on. Got a rough quote of about $500 for his part of it. That's about 5+ hours at $90 per. I can't blame the shop for charging for their time. I just don't know if I can justify the expense. Not having a band saw and not welding aluminum are hurting me on this job. I either need to find someone willing to do this work on their own time at home or just forgo that part of it. I can still do some cleanup of the runners from the bottom. I won't be able to go as far as I had planned.

Jut as you said, $500 for what I could do myself for next to nothing in a few hours if I had a band saw and a TIG welder. That is if I knew how to TIG weld. I can do pretty well on steel with my MIG. I'm enough of an old school farm boy to fab most any part on my bench with a saw, a file, a die grinder, and a welder.
 
yeah my wife was not thrilled when I spent $4700 on a mill and matched required tooling , about 10 years ago, or $2400 on a welder and a few accessories ,about 8 years ago,
but when
" I showed her a stack of receipts for machine work and welding jobs
( that were honestly just the tip of the iceberg as I don,t bother to keep all the receipts all the time)
and showed her that for example,
one job I did for a friend had cost me a bit over $1200 in machine shop costs, that Id had to pass on to the guy who was getting his car modified
vs about $290 It had cost me when I did a similar job once Id purchased a welder,
she eventually started to see the reasoning behind the tool purchases.
now what I didn't tell her was I did not charge the guy as much either,
so on the first job Id made about $200 for two long days work ,plus waiting on a machine-shop for several days,
on the second job Id had the guy buy me about $340 in tools for the shop, and he bought lunch for three days,
but he saved over $900 total cost in the process. so I felt we both made out ok.
Im not making any money, I barely average minimum wage levels,
but I acquire a good selection of tools and the people I choose to work with and help,
can,t come close too matching the price it cost to have the work done,
or work quality anywhere else.
no I'm not a great business man, I consider this an advanced hobby,
not a job, because I work how and with who I choose only when I want too,
yes I've lost money helping people lots of times!
and If the guys are not willing to get their hands dirty and jump into the project and help,
well, then I generally pass!
but I also have a decent reputation for doing things rather well,
and not screwing anyone over.
and as a result I have a reasonably long list of guys who call asking for info and help with projects and I get to work on what I want too when I want too.
 
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Wish I had the room for more high dollar tools, but I can't exactly keep them outside.
 
Wish we were closer geographocally. You could help me a lot plus, being cut from same cloth, I think we'd have fun.

More I think about it, I'm probably going to go ahead and have the fab shop help me on this. If I don't go all the way on this just over a few dollars, it'll bug me. I'm saving a lot by using the TB I already have. The price of the new TB, cables and harness adapters. Easily more than $500.
 
Wish I had the room for more high dollar tools, but I can't exactly keep them outside.
I have a shop at home but I have so much invested in the tools I use every day at work. I can't afford another set for the shop at home. It will be different once I retire. Then I'll bring my tools home and get more invested in my own shop.
 
As for progress on the XT, I've spent some time over the last few days studying the plenum inlet and taking measurements, deciding what to do with it as I design the adapter. The dual TB will change the flow path into the plenum. I'll redesign the entrance to capitalize on the changes. Ill design the adapter together with the entrance to make the most of it.

Should have everything i need to start on this part of the project by the end of next week. I'll post photos along the way. I expect feedback on my designs.
 
If you can, discuss potential mods before making major changes
(especially if its going to involve cutting and welding)
take clear pictures from several perspective angles
maybe draw with a marker on the manifold proposed cuts
don,t get so involved in the mods & process that you loose sight of the goals
and think things through, in many cases its at times smarter to sell a component thats not working as intended,
and start over with a new component design.

take accurate measurements and remember that theres always sub-assembly's like,
thermostat housings, coolant connectors, distributors and various throttle linkage,
and accessory brackets for air conditioners and alternators and,
power steering that must clear mods and adapter brackets

http://garage.grumpysperformance.com/index.php?threads/porting-can-help.462/page-2

http://garage.grumpysperformance.com/index.php?threads/calculate-fuel-injector-size.1200/

http://garage.grumpysperformance.com/index.php?threads/can-you-get-there-with-tpi.10494/

http://garage.grumpysperformance.co...h-ram-and-other-efi-intake-manifold-info.431/
 
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Thanks Grumpy. I am taking some time to think things through. I have a 52mm dual TB gasket that I used to trace out the proposed opening on the TB mounting of the XT, using black Sharpie. I have test fit the adapter plate to look at interference with the Tstat housing.

Before I cut anything, I'll take measurements under the hood , using the tpi as a model to check clearances.
I'll post photos of the marked up XT, showing my proposed cuts before I proceed to get your thoughts on it. I think this is going to be pretty cool and should work well.
 
Got some materials today. Attached is a photo of the runner exits with a Felpro 1205 overlaid. It's not as large a difference as I imagined. I took a quick measurement the other day but waited to see the 1205 comparison to know just where I'm starting from. For reference, that is about .125 material or less showing around the inside of the 1205 port openings. Now that I see this, I realize that I could take the runner exits out to the full 1205 dimension if I so choose, without any need for welding. There is a significant taper to the runners that I don't want to alter too much. The entrances measure at 2.05" x 1.59". The exits are 1.84" x 1.15". I've already determined that for now, I'll stop at a minor clean up of the exits and injector bosses. Therefore, it looks like a trim of about 1/16" around each exit, bringing them out to about 1/16" from the gasket openings. This will reduce the step up into the head ports without changing the runner shape too much. I'll smooth the runners up to the entrances but avoid changing the entrances which have a pretty decent shape. Those injector bosses are ugly. They're also thin walled so, I'll be careful smoothing and profiling them. I sure would like to weld them shut and weld on new bungs that don't protrude into the runners this way. Maybe when I go back into this thing in prep for the next motor.

I'm still playing with the idea of having the top cut off so I can actually get in there and smooth the plenum walls and runner entrances. I have found a semi retired welder who I'm going to visit tomorrow about welding a cracked manifold for a customer. I'll see what he says about my plans for the XT.
index.php
 

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your not the first guy nor will you be the last one too look at that slight over-lap the thicker runner casting,
on the runners have, and think, why bother,
what can a 1/16" of port wall hanging in the way ,in that runners port wall, restricting flow do?
hell its not worth removenig....
while it may not seem like it will do much, if done correctly the result will amaze you,
Yes the port work too match the runner cross section to the full Felpro 1205 overlaid gasket, is worth the effort.
opening the runners, too port match, the runner exit too match the gasket and blending that opening,
and blending it further up a inch or more, (as far as you can reasonably reach and still do the work smoothly,)
will produce a significant flow improvement if,
the opening and blend work is reasonably well done. that 1/16" to 1/8" you open the port wall,
will help noticeably
if we just take the figures you quote

The entrances measure at 2.05" x 1.59". (3.26 sq inches) roughly a 6000 rpm capability
The exits are 1.84" x 1.15".(2.12 sq inches) roughly a 4000 rpm capability port
thats roughly a 40% reduction in cross sectional area

CALCULATORS
http://www.wallaceracing.com/calcafhp.php

http://www.wallaceracing.com/calchpaf.php

http://www.rbracing-rsr.com/runnertorquecalc.html


http://horsepowercalculators.net/intake ... old-design



http://garage.grumpysperformance.co...cedure-step-by-step-guide-with-pictures.5378/

http://garage.grumpysperformance.com/index.php?threads/porting-can-help.462/page-3#post-72525

http://garage.grumpysperformance.com/index.php?threads/throttle-body-size-52mm-vs-58mm.641/

http://garage.grumpysperformance.com/index.php?threads/port-speeds-and-area.333/#post-37693
 
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For reference, that is about .125 material or less showing around the inside of the 1205 port openings. Now that I see this, I realize that I could take the runner exits out to the full 1205 dimension if I so choose, without any need for welding.
This info maybe helpful ....

FelProGasketDimensions01.JPG

CylHeadMinPortCrossSection01.JPG

PeakTorqueTable01.JPG
 
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Thanks IndyCar. Now that I have the intake gaskets and porting rolls, I'm ready to mark up the runner exits and get to work on those. I want to get the tb adapter finished first though. Unfortunately Edelbrock goofed on the tb gasket that i ordered for the XT. I need it to use as a pattern and then ill use it to seal the adapter to the manifold. The gasket came in the correct package marked P/N 3813, but the gasket in the box is not a 3813. Weird really. Dont know just what P/N it is, but it sure doesn't fit the XT. Summit has the right part on the way. Told them to double check the package in case eddy fouled up on more than one.
 
Thanks Grumpy. I missed your reply earlier. I was going to sit down at some point and calculate the taper. Thanks for doing that. I was guessing it at about 30%. Looks like that was an underestimate. I see your point on bringing the runners out to the full 1205. I got a 6" mandrel to reach into the runners as far as the runner entrances. That way I can produce a good runner profile as I open up the exits.
 
I was just thinking yesterday about the runners on this XT. They aren't truly rectangular but rather have rounded vertical sides. I'm sure that's to encourage flow from the plenum. Because they aren't rectangular, the true csa is less than the product of height times width.

Two of my sons are engineers. The youngest told me of an equation he learned in applied calculus that can quickly determine the csa of any shape. I think I'll have him run that equation on the runner entries of this intake to see what he comes up with.
 
Two of my sons are engineers. The youngest told me of an equation he learned in applied calculus that can quickly determine the csa of any shape. I think I'll have him run that equation on the runner entries of this intake to see what he comes up with.
Now that sounds very interesting. What I want to see is how you measure the port for the
input to the equation.
 
and posting the math here would certainly not hurt either
 
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