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My TPI Breathe Build

Old 01-27-2019, 09:54 AM
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My TPI Breathe Build

Well I have been a member here for about 4 yrs now and have done a few projects on the car but never done this, a project thread, so here I go .Like alot of us I want a few more ponies from my TPI. I have done the "freemods" and cleaned and dressed up the engine and aside from the absence of the smog pump the engine still looks stock. I want to maintain this look and I am willing to leave a few HP on the table to achieve this. There are plenty of threads that show to to flow a TPI system and I want to do it my way with using stock parts as much as I can. I will be going through the entire air intake system and finishing with the exhaust system. This may take me a few as I don't work fast anymore and am working weekends at the moment.

I Purchased a set of new AS&M runners from a member here. I chose these as they have the stock look. The SLP and Edlebrock flow better but I do not like the look of them. AS&M still sells these sometimes? The old TPIS looks stock also but good luck finding those. These are the biggest purchase of the project.




I will be retaining the stock TB as I have researched those to be good for at least 300HP which I will not be getting out of this build. The new runners will fit right in with the look of my engine bay!







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Old 01-27-2019, 10:08 AM
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Re: My TPI Breathe Build

The runners are the "bottleneck" of the air intake system. After doing my research and getting the runners and gaskets I quickly realized that there are a few more "bottlenecks" along the way. I would not get the full effect of the large tubes if I just swapped out the runners. So I went and bought a used Plenum to gasket match up.





As you can see the hole sizes are small, not round and have restrictive tabs in the end ports. Let alone the "wall" in the inlet behind the TB. I did not take a pic of that. I looked at some aftermarket intakes as that has it's own restriction issue!. As I stated I wanted to use mostly stock parts, so I purchased a intake manifold from the same car where I got the plenum.



The runners you must purchase aftermarket, there is no way of "hogging" those out, they are to thin.
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Old 01-27-2019, 10:39 AM
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Re: My TPI Breathe Build

My plan is to port and gasket match the plenum and the intake manifold. I have never done this before and I am going to purchase some basic tools that can be had at the home improvement stores. After all it is just aluminum right? I bought these parts to work on so I could still drive the vert during this time of year here in FL.

My plan is to also replace the injectors, EGR valve and maybe do lifters, rockers and push rods, my original Multec's work perfectly but Bosch 3 will deliver more fuel to go with more air. I will pose that question to you all later for your opinions.I may need a tune also. I will not be doing the heads, cam and exhaust manifolds For this project I do not want to incur the extra work and costs.

I do not have any HP goals with this project, maybe if it gets it to 250 or so. The runners state a 20%-25% increase so throw in the port work and a better exhaust I think 30=35 HP gain is not unrealistic. I have a mechanic customer that owes me a trade so I may have him do the parts swap when I am done with the work.

I got some basic drill tools to start the porting of the plenum




I bought the drum sander kit in 3/4, 1, and 1.5"



This extension is the ticket! You can put any of the round shank tools in the end and lock it in. The lower end is a hex that fits in any drill. they make a 12" that will reach all the way into the intake manifold! The rasp also fits this extension.
I will be doing all the machine work myself. I have no prior experience at this but if my plan works anyone should be able to do this at home. I have tried the carbide cutters but they are expensive, you have to order them online or go to a tool store and no matter how much WD 40 you spray on them you can't stop them from clogging.

Last edited by vinny R; 01-27-2019 at 10:44 AM. Reason: no pic.
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Old 01-27-2019, 10:56 AM
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Re: My TPI Breathe Build

I am going to start with the plenum. I am going to use a jig saw with a metal cutting blade to do the rough cut I traced out the gasket holes with a fine point sharpie and did the rough cut. Next I took the rasp put it in the drill and cleaned up the cut. That thing is bad ****! It removes metal like a mother! Best $4 I sent so far. Next I took the 3/4" drumm sander and cleaned it further. At this point the 1.5" drum sander fits inside the hole. It does not fit with the factory opening. Put it in my air Die grinder and moved it up and down and round and round. As you do this it kinda rounds out the holes as it is only about an 1/8" smaller than the hole. When I was done the hole looks more round the the factory cast!



You can really see the size difference of the new runners! Just common sense looking at this and you can see why you need to mach the components for maximum flow.



Now off to the other side and the inlet!
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Old 01-28-2019, 12:16 PM
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Re: My TPI Breathe Build

Fun stuff - keep us updated!
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Old 01-28-2019, 03:52 PM
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Re: My TPI Breathe Build


Try some cutting bits with long shanks. This will help cut down on time. Sanding drums are for finishing.
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Old 01-28-2019, 04:02 PM
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Re: My TPI Breathe Build

Nice work Vinny! ....following along!
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Old 01-28-2019, 05:45 PM
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Re: My TPI Breathe Build

Originally Posted by tealman92 View Post

Try some cutting bits with long shanks. This will help cut down on time. Sanding drums are for finishing.
Do you know where you can buy these? I know the home improvement boys do not carry them. I used to have a industrial tool supplier but they closed up a few yrs, back.

Also do you have any tricks to solve the problem in the pic below.I started by borrowing these cutters. I saw on youtube where they say WD 40 but that just prolongs the inevitable. I cleaned these once with a torch and a wire wheel but that is a PITA. Maybe it was the die grinder spinning to fast? I have noticed the drill works better even with the drum sanders. I think the slower speed is better for soft aluminum.



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Old 01-28-2019, 05:48 PM
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Re: My TPI Breathe Build

Originally Posted by Abubaca View Post
Nice work Vinny! ....following along!
TY Chris!
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Old 01-28-2019, 06:36 PM
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Re: My TPI Breathe Build

Sweet thread! I'm watching. You are doing all the right things. I've read our TPI induction can support over 450HP with just some opening up. I think you or I should have snapped up that extrude honed manifold renegade69 was selling.

Last edited by Tootie Pang; 01-28-2019 at 06:41 PM.
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Old 01-28-2019, 07:54 PM
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Re: My TPI Breathe Build

You use a slower rpm so they dont melt the aluminum. You can get them easily on amazon. They also make ones specifically for aluminum.
You will be able to do the job in hours instead of days.
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Old 01-28-2019, 07:56 PM
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Re: My TPI Breathe Build

Originally Posted by Tootie Pang View Post
Sweet thread! I'm watching. You are doing all the right things. I've read our TPI induction can support over 450HP with just some opening up. I think you or I should have snapped up that extrude honed manifold renegade69 was selling.
450 is doable but the base manifold has to be cut and welded to change the port entry into the heads. The biggest problem with tpi is the base manifold.
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Old 01-29-2019, 07:49 AM
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Re: My TPI Breathe Build

Originally Posted by Tootie Pang View Post
Sweet thread! I'm watching. You are doing all the right things. I've read our TPI induction can support over 450HP with just some opening up. I think you or I should have snapped up that extrude honed manifold renegade69 was selling.
The funny thing is Tootie that after I bought the runners I looked for 2 or better weeks and could not find a single, good condition, honed manifold for sale! So I found this used parts guy here in FL and purchased my stock parts.Then a few days after I bought the used stuff to do my own, that one and another one and another just kept popping up for sale, geeze! I thought about buying renagades anyway and just selling the stock one I bought, but the more I thought about it this is something I have always wanted to try myself, So I just decided to go with my plan!
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Old 01-29-2019, 07:50 AM
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Re: My TPI Breathe Build

Originally Posted by tealman92 View Post
You use a slower rpm so they dont melt the aluminum. You can get them easily on amazon. They also make ones specifically for aluminum.
You will be able to do the job in hours instead of days.
TY, I will look for the aluminum specific!
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Old 01-29-2019, 08:36 AM
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Re: My TPI Breathe Build

Vinny, you need to make sure you're using the right burrs for aluminum. I did all my port matching with two burrs, and with using WD40, I only had to clean them a few times with small wire brush. Very easy. ....I have heard that the WRONG burrs with gum up like that. Couldn't tell you what is right and what is wrong though. I didn't know that when I got mine though, I just got lucky!
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Old 01-29-2019, 09:06 AM
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Re: My TPI Breathe Build

Nice work Vinny! Id love to see a before and after 1/4 time.
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Old 01-29-2019, 12:17 PM
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Re: My TPI Breathe Build

Originally Posted by vinny R View Post
Do you know where you can buy these? I know the home improvement boys do not carry them. I used to have a industrial tool supplier but they closed up a few yrs, back.

Also do you have any tricks to solve the problem in the pic below.I started by borrowing these cutters. I saw on youtube where they say WD 40 but that just prolongs the inevitable. I cleaned these once with a torch and a wire wheel but that is a PITA. Maybe it was the die grinder spinning to fast? I have noticed the drill works better even with the drum sanders. I think the slower speed is better for soft aluminum.

This is THE bit to get- I used it on my manifold and it eats aluminum like no ones business and never clogs.
https://www.ebay.com/itm/13288813362...item1ef0bffffa
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Old 01-29-2019, 12:32 PM
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Re: My TPI Breathe Build

Originally Posted by dmccain View Post
Nice work Vinny! Id love to see a before and after 1/4 time.
I do have a drag strip close to my house that does the test tune. I have been afraid to take it out there and actually see how slow she is! But for what I am doing it would be a great way of seeing actual results. Great idea man! This may throw my **** dyno results off!
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Old 01-29-2019, 12:49 PM
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Re: My TPI Breathe Build

Those dont look like the right burrs for aluminum

you want non ferrous burrs which dont have many “teeth”
https://www.summitracing.com/parts/s...iABEgKyDfD_BwE


but wd-40 constantly and often helps alot

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Old 01-29-2019, 12:53 PM
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Re: My TPI Breathe Build

Thanks for the advice on the cutting burs guys. I found these on amazon and going to order them tonight. These are specific for aluminum. You can see the difference in the blades, just as Abubaca pointed out. The ones I pictured are for steel. So between that and the high speed of the die grinder i see why WD had not much effect.



These are the extended shaft aluma cut tungsten carbide. $60 for the set of 4.
Below is one made for cast iron/steel and you can clearly see the difference in the blade pattern. This looks like the one I have that gets all clogged up.

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Old 01-29-2019, 12:59 PM
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Re: My TPI Breathe Build

Yeah those open designs will eat thru aluminum so go slow loland the wd40 works well with them
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Old 01-29-2019, 01:26 PM
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Re: My TPI Breathe Build

I buy my burrs at McMaster Carr. I don't think the burrs are made specific for aluminum so much as just the design of the flutes. All of the ones shown are either single cut or double cut burrs, and I have used both on ferrous and non ferrous metals and they both work equally well, it depends on how fast you want to remove the metal. If you use the double cut burr on soft metal you can use a lubricant, but I don't find that works well, or too long. I just keep my file card handy when I use it on aluminum and I brush the burr periodically so it doesn't look like the one that has the aluminum coated around the burr like peanut butter. Stop every couple of minutes, brush out the build up and continue on. This is basically what I have
Amazon Amazon

Last edited by scooter; 01-29-2019 at 01:41 PM.
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Old 01-29-2019, 01:34 PM
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Re: My TPI Breathe Build

Originally Posted by Orr89RocZ View Post
Yeah those open designs will eat thru aluminum so go slow loland the wd40 works well with them
Will Do Orr
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Old 02-01-2019, 03:37 PM
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Re: My TPI Breathe Build

Be careful when you use the new burs. They remove ALOT of material real quick. Keep WD40 handy and spray the part and the but occasionally. This will help reduce the amount of fouling in the flutes of the burs. The walls of the lower intake are not of a consistent thickness. With the burs you have ordered, it will be possible to machine a hole in the intake while porting.
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Old 02-03-2019, 07:52 AM
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Re: My TPI Breathe Build

I made some good progress this week and I finished the plenum. I was going along so good that I forgot to take a before pic as I just went right into the inlet after I finished the passenger side runner holes. I will be ordering the cutting burs later today. My wife wanted me to wait so we could group some other stuff she was ordering from the same place. I used the tools I already had and I really want the burs for the manifold.

I started with the jig saw and cut out the machined tapered lip that chokes down the air into the plenum. I continued with the saw and proceeded to cut into the "wall" with the jig saw. I did switch the blade to a more aggressive wood/metal blade. The metal blade was getting clogged with aluminum, the teeth are to small. I do apologize for not taking photos of this part, I am new at this build thread stuff! I came down from both sides of the circle and met in the middle of the bottom of the wall and the piece fell right out. Next I used the rasp on a drill. Guys I gotta say again, the best $4 tool in the arsenal! I went to town and cleaned up the circle cut, took down the bottom of the wall and removed the intrusions of the plenum sides. Now this is where you need to be carefulll as Hawgtied warned. the metal is real thin on the plenum sides. You want to remove material from both sides as it intrudes into the opening, just don't go to far! Next I used the 1.5" drum sander with 50 and went in there and not only smooth the rasp work out but it did a good job of removing the last little bit of metal from the inner part of the inlet. There is a "hump" from the wall that I want to knock down some. Next I put a 120 grit on the small drum sander and polished it up.



I took a flat block I had and covered it 220 sandpaper and went over the flat gasket surfaces to smooth out the outward burs you get from working the openings. I taped of the openings and shot a coat of paint on the exterior. I found this rustoleum paint and the color is aluminum. I must say, it does look the part when painted. I used it on the engine currently and the heat does not bother it or turn it yellow.



Below is a photo I found on the net that shows the plenum in a before and after. You can see all the restrictions GM felt necessary.



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Old 02-03-2019, 08:15 AM
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Re: My TPI Breathe Build

If you have noticed how much cleaner the plenum looks I have been cleaning it in between cuttings, I am using ZEP 505 Fast Industrial Decreaser. This stuff eats carbon better than carb cleaner! it does not evaporate and can be washed off and the carbon just flows away.

I have to confess I have a problem with spray paint, I am addicted! I paint everything, if I take a part off the car even the nuts, bolts, and screws get painted! After I painted the outside of the plenum I cut open the intake holes and painted the inside of the plenum with caliper paint. It is high temp and chemical resistant so I don't see an issue with it failing over time.



Next I painted the vacum hose fittings... see above confessions

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Old 02-03-2019, 08:33 AM
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Re: My TPI Breathe Build

Behold the finished product! Ready to get stashed in my closet next to the runners. This entire part of the project took me about 1 day worth of work. I do believe that someone who works a little faster, has a little more knowledge and just does it all at once it is probably 4-6 hrs. You may save a little time with the proper burs but to remove that wall in there it is just time consuming. It is thick and the hump in the center is tall. When you are all done this will support a 52mm TB if your build requires that.





Gaskets all matched up nicely!



I did not pic the inlet gasket but my opening is slightly larger than the gasket.



Chloe is my dog chilling with me while I post these pics!
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Old 02-03-2019, 08:39 AM
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Re: My TPI Breathe Build







I am going to wait to get the burs before I start the manifold. I am going to make a run with the rasp just to see how it works on the manifold. But first it's off to get a gallon of Fast 505 and start cleaning this nasty thing up!

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Old 02-03-2019, 10:37 AM
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Re: My TPI Breathe Build

Looking good Vinny! .....I spend Saturday pulling the old rear, and stripping down the brakes to put 'em on the NEW rear. ...my buddy said we could do it in a day. I said "are you kidding me", I clean and paint EVERYTHING!!!! LOL, just like you said!
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Old 02-03-2019, 03:32 PM
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Re: My TPI Breathe Build

Nice work! What part of FL are you in? Tampa Bay for me...
AS&M always made the TPIS Runners...
I thought the AS&M runners flowed the most, since they were thin walled as opposed to cast like all the others...
I know people hogged out the SLP and got more flow, but I too like the "stock look" of the AS&M.

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Old 02-04-2019, 07:02 AM
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Re: My TPI Breathe Build

Originally Posted by luvofjah View Post
Nice work! What part of FL are you in? Tampa Bay for me...
AS&M always made the TPIS Runners...
I thought the AS&M runners flowed the most, since they were thin walled as opposed to cast like all the others...
I know people hogged out the SLP and got more flow, but I too like the "stock look" of the AS&M.

Raf
I am in (or on) Jupiter.
You are right about the cast thing, but with my limited knowledge of this I have heard that the SLP's and such are shorter and fatter so more CFM's can get through. Maybe someone else here knows for sure. I did not know that AS&M made the TPIS, that makes sense as they look the same.
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Old 02-04-2019, 07:44 AM
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Re: My TPI Breathe Build

And Edelbrock made the TPIS intakes for them too... TPIS later did some CNC porting to them before selling them...
Let me know how it goes with your car... I've got some parts, AS&M Runners, Ported / Extrued Honed base, Teick Flow Heads (all in box).
My ported plenum is on the car though... I have a 91 305 5 speed, and while it's fun, I'm sure it would be more with those parts... but moving in a couple years and may keep parts to sell if need down the road...

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Old 02-04-2019, 07:45 AM
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Re: My TPI Breathe Build

Great work Vinny! I like the look of those runners..stock appearance aspect of them.
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Old 02-04-2019, 09:12 AM
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Re: My TPI Breathe Build

Originally Posted by dmccain View Post
Great work Vinny! I like the look of those runners..stock appearance aspect of them.
Thanks Dmccain! I am pretty impressed myself, it I do say so. Hopefully I can translate the same quality of work to the base!

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Old 02-04-2019, 11:59 AM
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Re: My TPI Breathe Build

I'm following this closely as this is mirroring my current build direction. I have an Edelbrock base on the way that I just ordered and a set of AS&M runners as well.
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Old 02-05-2019, 08:34 AM
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Re: My TPI Breathe Build

You may discover that without those humps in the plenum floor behind the TB, the transition from idle to part-throttle could get a little unstable. I believe that was a band-aid applied by the factory to address that.
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Old 02-05-2019, 11:56 AM
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Re: My TPI Breathe Build

Originally Posted by Vader View Post
You may discover that without those humps in the plenum floor behind the TB, the transition from idle to part-throttle could get a little unstable. I believe that was a band-aid applied by the factory to address that.
I always wondered why they put them there and would really like to know if this is the case. Maybe it is a air reduction to match the other restrictions in the TPI system. From my common sense world it looks like it is there to create vacuum to suck the air in from those 2 holes. I think they connect to the PCV valve. I am to think if the air is rushing in the plenum it will block the flow coming from the pcv system. The pressure is greater coming in the plenum than the crankcase pressure, so without the wall, less bad air into the engine? Maybe excess pressure in the engine? I have seen countless threads where people port the plenums all the time and have not read any side effects, but I can't say for sure.
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Old 02-05-2019, 01:32 PM
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Re: My TPI Breathe Build

Originally Posted by vinny R
I always wondered why they put them there.
It was more of an in lieu from GM. Remember that drive-ability was more of a concern for them, not all out power. The TPI's were very restrictive, and the factory valve train essentially ridiculous. Wouldn't surprise me if they were having an off idle issue with the plenum being wide open, and rather than go back into the prom to somehow compensate for it (time constraints), they just added a barrier/obstruction to slow the incoming air down...

- Rob
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Old 02-09-2019, 09:37 AM
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Re: My TPI Breathe Build

Great thread......keep going.
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Old 02-10-2019, 07:31 PM
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Re: My TPI Breathe Build

Originally Posted by Jetmeck View Post
Great thread......keep going.
Thank you sir! I will

Got the manifold cleaned up and the patient ready for surgery. The new cutters have arrived and I am ready to go! It is amazing how good that 505 cleans. It is much better than Gunk IMHO and washes off clean. This is after 2 cleanings and a couple hosings.



I am not going to use any air tools for this part of the project. I will be using the cordless drill I think slow and low is the way to go. Below is a couple pics of what the entry ports look like in the factory cast. Well you can see the big, about 1/8" lip on the left side, flat spots in the circle and very rough overall casting on the inside walls. Now all I can say that if you want air to "flow" well this just is not going to help.



This crappy casting looks the same on pretty much all 8 ports. I hope to remove that left side edge and enlarge the overall opening of these ports.

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Old 02-10-2019, 08:00 PM
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Re: My TPI Breathe Build

I had some time yesterday to start the port work. First let me say as the other poster said those cutters I bought will CUT! He was spot on. If you press to hard they will "dig" in so be careful if you try this at home. I found the cutters used on the drill and keep them lubed and moving they worked great.Use light pressure and constant motion. I used the cutter to take the majority of that left side restriction and then followed up with the rasp. The rasp leaves a better finish in the aluminum and still removes a good amount of material. You could use the rasp only but it would take longer and you need more pressure on the tool. I kept both lubed with WD and neither clogged, the combo worked great together for a DIY guy.



As you can see I pretty much did just the opening and have not ventured down the tunnel yet. I also chose to start on the right front. The first port shares the wall with the water passage in the manifold so I really go be careful and go slow, especially on the right side. I have the first pass on the first 2 ports. I am happy with the results so far. I have only used the cutters and the rasp so far. I figure I do this in stages, openings first, inner passage and head side last. This way I can kinda assembly line it.



I know this pic is not the best but you can really see how much each port is opened up. I will draw out some gasket lines next but I think I will keep up on step 1.
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Old 02-11-2019, 04:51 PM
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Re: My TPI Breathe Build

Originally Posted by luvofjah View Post
Nice work! What part of FL are you in? Tampa Bay for me...
AS&M always made the TPIS Runners...
I thought the AS&M runners flowed the most, since they were thin walled as opposed to cast like all the others...
I know people hogged out the SLP and got more flow, but I too like the "stock look" of the AS&M.

Raf

I get wanting it stock looking. Theoretically SLP are stock. They were available from GM dealers.

So either way.
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Old 02-11-2019, 07:41 PM
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Re: My TPI Breathe Build

Well I was having some issues last night when I was posting this and did not finish. Between my computer and phone acting up to me being sun burned out from parking cars at my club's car show I just gave in.

After the first pass I decided to go a little further with the ports, a little deeper .The pic below I did a finish run. I used the flap wheel and used a in and out motion to create a cross hatch pattern. Similar to a cylinder hone.I used the slow speed on the drill for this. I take it this is where the term "honed" comes from when they talk about the intake manifold. I actually have a small engine hone (and know how to use it) so this is actually something I do have knowledge on. When done it is not like a polish smooth but is still pretty good. I may leave it as is when finished.





after I looked at this and drank a bottle of thinking fluid I was not happy with the opening. If you look close you can see it is still choking down the port. I then thought of the words from the OP's about how thin the walls are and after more "thinking" I decided I want to remove some more aluminum. I have noticed that the left side and the top is pretty thick especially in the front. There is a casting mark that runs down the right side. I went slow and low as stated and took more from the left and the top. I used the casting mark on the right as a guide and just took enough to get rid of the mark and smooth the wall, This area on the right about 1/2 way or so in looks to be one of the thin spots mentioned. I had earlier marked my gaskets out so I was careful to not open that area. I used the rasp after the cutter just like step one. Now I am happy (and got a nice buzz) and as you can see the ports are happy too! I did not run the flap wheel on this yet. I have not touched the other side so that will be next. I am a little over 1/2 way down the port and running out of reach with the rasp. I think I will JB weld a new rasp to a bit extension to get it all the way down. This will hold it firmly in place as the magnetic holder does nothing.





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Old 02-11-2019, 07:48 PM
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Re: My TPI Breathe Build

Looking good, you will want to remove the Allen head pipe plugs on the bottom of the plenum and clean out the shavings.
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Old 02-11-2019, 07:54 PM
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Re: My TPI Breathe Build



I have about 4 hrs and a 6 pack into the manifold thus far! I have about an hr, in just getting used to the cutters so I think it will move a little quicker now. I also feel more confident in me. This is something I have always wanted to do so I am really enjoying the whole process so far, actually enjoying the time I am putting in.

While I am working on this part I want your guys opinion on manifold gaskets. I have always used Fel-pro and liked their gaskets. Is there a certain number gasket I should use? Are they all the same or is there a certain one I should use based on thickness and such? I would like to order the gasket set so when I get to the head side of the manifold I can match it up.
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Old 02-11-2019, 07:57 PM
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Re: My TPI Breathe Build

I think felpro 1204 is the closest to the port size.
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Old 02-11-2019, 08:01 PM
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Re: My TPI Breathe Build

Originally Posted by Tuned Performance View Post
Looking good, you will want to remove the Allen head pipe plugs on the bottom of the plenum and clean out the shavings.
Thank you Brian...Will do!
I was going to reach out to you when I was done with the work for your advice and help if you think I will need a tune? If so I will need you for this. Also your thoughts on whether I should change, upgrade the injectors.
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Old 02-11-2019, 08:06 PM
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Re: My TPI Breathe Build

I’m not a big fan of your multecs.
Delphi’s should be a direct replacement
https://www.southbayfuelinjectors.co...-1986-1992-851

bosch 3s will work as is but you will run alittle lean without tuning.

https://www.southbayfuelinjectors.co...fuel-injectors
The only way to know how it’s running is to datalog with tuner pro rt. You would need a cable from aldl cables.com or moates.net extreme aldl cable. It should run great as is with the Delphi’s but the Bosch will need some tweaking.
You just missed a 15% off sale
The bosch injectors also have a loud tick to them like a lifter noise just a FYI.
You should also use new o-rings on the fuel rail. You will have a few left over for 85-88 cold start injector. Standard motors sk24 on amazon or

https://m.autozone.com/fuel-delivery...5_327287_24890


Last edited by Tuned Performance; 02-11-2019 at 08:22 PM.
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Old 02-12-2019, 07:42 AM
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Re: My TPI Breathe Build

Originally Posted by Tuned Performance View Post
I think felpro 1204 is the closest to the port size.
Below is a pic of the Fel-Pro gasket set. Those metal plugs in the middle, do you know if those pop out? On my manifold one side is blocked by the factory casting. The other side is open and needs to flow throgh fom either the EGR or PCV systems

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Old 02-12-2019, 09:26 AM
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Re: My TPI Breathe Build

Originally Posted by Tuned Performance View Post
I’m not a big fan of your multecs.
Delphi’s should be a direct replacement
https://www.southbayfuelinjectors.co...-1986-1992-851

bosch 3s will work as is but you will run alittle lean without tuning.

https://www.southbayfuelinjectors.co...fuel-injectors
The only way to know how it’s running is to datalog with tuner pro rt. You would need a cable from aldl cables.com or moates.net extreme aldl cable. It should run great as is with the Delphi’s but the Bosch will need some tweaking.
You just missed a 15% off sale
The bosch injectors also have a loud tick to them like a lifter noise just a FYI.
You should also use new o-rings on the fuel rail. You will have a few left over for 85-88 cold start injector. Standard motors sk24 on amazon or

https://m.autozone.com/fuel-delivery...5_327287_24890


If you are going to do a custom tune then I would say go ahead and play with the injectors, if not, I would recommend just putting it all together and not changing too many things at once...
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