Hello folks,

I want to share with you my -more or less- freestyle build/swap conversion to an Edelbrock Pro Flo 4 XT from tpi.
This thread is about making my personal experience with this swap and to help all the others who has thought about doing it.
In process of beginning, I want to thank E.T. Garage for some good valid information in his videos about that chinese copy of the pro flo 4 xt.
Here is the link if anyone is interested:


So after watching his videos the fitment difficulties and problems are manageable, at least I thought so.
It happened the way it had to, I purchased one manifold for me on ebay.com and now trying to make that whole thing fit.
First tip here, like the guy in the video told, if you find a cheaper pro flo somewhere (for example on amazon), just copy the link and make the seller an offer with the listed price. They will accept it. Some bucks already safed if you just want to purchase through ebay like me. And you will need some money..

So the manifold arrived today. Attached are some photos of the -as is- quality when it came to my door.



The first look was okay, but....



The second look shows too deep machining at the place for the injectors. This is on the injector number 1,3,5 and 7 (passenger side looks solid).
The guy in the video warned about that, he had that problem also. So since it need to be welded, I attached pics of the problem in a message to the seller and requested a partial refund. I will let you guys stay tuned about that.



The injector holes look pretty rough, sharp casting rests here...


Just some mild porting and cleaning needed here, no big deal. Work for the soul at afternoon.



Next problem I found was that the right thread of the thermostat housing and the thread underneath it ended in each other...


If you watch closely you can see light shining out of the hole. No real problem as well because there is no coolant passage there ending in.



For the ports I dont really have something to complain about. I´ve seen worse castings. Sure it needs to be opened up at the entry for the cylinder head to match 1,99" x 1,23" on my trickflow 175cc heads.


I had a dent (some alu material pushed in) on one gasket surface, not nice but I can cut and grind it flat.


The coolant passages look solid as well, just a clean up needed...



I will let it get welded the next days and then inspect all threads and start by making my tpi 48mm throttlebody work with it. Or should I start with other steps?
What you guys think? I paid 400$ shipped and clearanced to Germany, not too bad for me.

If this review is requested and well recieved till yet, I can continue posting further steps of the swap and the all around work.
Greetings,

Chris

 

Probably wouldn’t of been much more for a nicer used one

https://www.ebay.com/itm/35568859056...mis&media=COPY

 

The build has been completed. For those who are interested in some details, I put some photos in. Feel free to ask. Definetely a good improvement over ported tpi manifold.

 

How does it feel in the bottom end? I've been seriously thinking about getting one for my tpi swapped 92 k1500.

 

Did you adjust the calibration at all?

 

Didn't realize they were all over Ebay for 200 bucks. What about hood clearance for a Camaro. And I'd be interested in the tune as well. Im running an HSR right now, be interested to see what changes were made.

 

Feels still very strong in the bottom end. The torque curve is more linear now from bottom rpm on up against the peaky tpi torque curve from 2500-3500rpm. For my feeling, it didnt loose bottom end but gained sooooo much top end🤩😬

Yes, Im still using the modified apym prom but changing to fitech soon. I would definitely recommend to tune After swap. The new higher breathing capability needs to be adressed.

I just know the hood clearance for a Firebird Formula hood with new stock motor mounts. It fits without modifications to the hood and im still having a finger width space between the dual tpi throttlebody adapted to the XT manifold. But it depends on how low you gonna drill the holes for the adapter. I can post pics if you need.

And for the tuning: Im not sure what you want to know but feel free to ask if you have specific questions.

I want to admit: Changing to the pro flo xt is not the easiest work. It needs some modifications!!
But its well worth it.

 

I have an Edelbrock pro flow XT on my 82 trans am. I have poly engine mounts and had to cut a relief in the brace on the stock hood. It was more for the throttle body vs the actual intake. If the one in this tread has a similar rpm range it revs well. I've had mine up to 6k regularly and it has no issues. Torque down low is good also.

 

Basically just if you did any tuning on it. Or are you running the base TPI tune?

 

Nope. Its not stock tune. Main changes are pretty standard: timing, fuel wot and acceleration enrichment. Im switching to fitech soon since its easier to handle.

 

Very cool! Can you give more details/photos of the throttlebody adapter? Did you fabricate it or did you have someone else make it?

 

About an 1" thick aluminum Plate needs to be drilled for the correct bolting of the OEM throttlebody. Place the Adapter plate as low to the pro Flo flange as possible to provide hood clearance with the 48mm throttlebody.


After drilling and tapping the adapter holes for the mounting of the body its critical to cut enough material off to provide the throttle blade movement and a smooth air transition. You can see where I was going to cut.

 

If you swapped driver and passenger side valve covers it would put your oil fill in a easy to get to location on the front driver side of the car.

 

It probably gained bottom end vs. the stock TPI. All but one (the Mini Ram) aftermarket intake in my 10x the tork take too" test, gained low end torq over the stock TPI. See HERE.

Or, right HERE

 

god job on the TPI TB adapter plate. Have a pro flo and went LS1 tb and haven't yet figured out how to retain cruise control - and am starting to miss it!

 

I decided to pick one of these up. I am happy to say that it seems they sorted out the casting errors. Rather than start my own thread, let me add some pics of my build to help anyone else undertaking this project.


View of the 1 inch aluminum adapter plate under fabrication.

Before porting overlayed with a 1205 gasket.

Getting close!

 

 

 

I ported the drivers side using the traditional carbide burrs and sandpaper abrasive rolls. This method is effective but takes time to master, creates a huge mess, and poses the risk of gouging the aluminum from bad technique or a moments loss of concentration.

That’s when I came across an elegant solution considering the straight tunnel ram style. Use ordinary metal files! They are very precise, carry a low risk of damage, and so clean you can work on the intake on your desk at work!

 

I love that.

 

Been tempted to get one of these for my C4 TPI car but i got enough to do atm.

 

You are going to need to figure out what you want to do for the throttle cable bracket. The included piece mounts on the wrong side and does not fit the OEM throttle cables.

i decided to fab my own from sheet metal and a bit of “stakin tacks” with my mig welder. I plan on drilling and tapping the plenum.

 

 

HEADS UP!

For anyone porting take notice that there is a single thin casting on the cylinder 5 runner (third runner back on the driver side) where the surface was milled for a bolt.




The proper fix would be tig welding but I bet a patch made of 2-part metal epoxy and carbon fiber will work fine.

and let’s be honest, the best part of this intake is how insanely cheap this thing is. Can you imagine if 15 years ago there was an “as cast” intake that outperformed a Super Ram (according to Motor Trend) for $200? https://www.motortrend.com/how-to/vemp-1010-edelbrock-pro-flo-xt-intake

 

This looks nice. I'm wondering if you will need to add a plate at a 90* angle to stop that long ear for the cable from flexing?

 

Good point. I occasionally get throttle sticking in my current Holley TPI setup from the stock bracket. Damn annoying!

I will pay attention to this when I get around to installing it this winter. And I left that “ear”…”Dumbo sized” under the assumption I may need to relocate that throttle hole position.

 

…and my wife says I never listen…

 

Hi @ Chris_Formula
I can't send pm, how can I contact you? I have a several question reagrding this manifold. Thx

 

@ mativ8: Post your question here so that everyone can benefit from this thread.

 

First: What fuel pressure regulator did you use? The one from Edelbrock or different one?
https://www.edelbrock.com/fuel-injec...le-43-psi.html
Second: Do you have any other pictures of the adapter plate? Could you please provide me the external dimensions of the aluminium plate?
Third: What thermostat neck did you use? Does the stock TPI fit right?
PS. I will be instaling Fitech as well

 

I used an adjustable fuel pressure regulator for the 5.7 LT based engines. Its the same design like the edelbrock‘s

The throttle body adapter plate? Sorry they’re the only one I have.

Thermostat Housing: 10108470 GM Performance

 

Was the retainer for FPR in the FPR kit? Do you have a part number for the kit as well?

 

 

The 01 is the high pressure (58 psi) model. You are essentially paying an exorbitant amount of money to be able to retrofit a stock LT1 fuel pressure regulator to work with the intake fuel rails.

I assume someone else has had to develop a more reasonably priced alternative. However, after extensive searching, I simply couldn’t find it. You’re stuck using an aftermarket adjustable fuel pressure regulator or buying this kit to get the adapters necessary to use a stock fuel pressure regulator on a aftermarket fuel rail.

 

Did anyone try to use LS1 throttle body? I sent message to Fitech if it this could work but they replied that they didn't test.