Tuned Port style EFI w/ conventional sbc heads
 

I like the idea of EFI on a Gen 1 SBC and really like the tuned port style intake. What are the options or real world experience vs throttle body/ direct port inj? Worried about hood clearance with this Holley style "ram" efihttps://cimg4.ibsrv.net/gimg/www.cor...6cc22bae2b.jpg

The TPIS mini ram or equivalent is what I would like to use with a stock height hood:
https://st.hotrod.com/uploads/sites/...mage_large.jpg

Looking for real world experience from users or??

I am happy to give some feedback on TBI and future plans.

For starters, my TBI install is documented here.

I went with TBI because it is a great platform for future plans. What I mean by this is that any EFI install requires an improved fuel system with larger return line and electric fuel pump. Plus wiring and provisions for an ECU. For TBI, that is pretty much it. Simple system, so easy to troubleshoot. Baby steps, if you will. I did a GM OEM system because parts are cheap and readily available at local pull a parts. Everything fit fine under the hood and the driving experience is much better. No longer lots of cranking to get the car started.

Everything has been running well for several months. I have been putting together parts for a TPI system. Going this path for the "cool" factor more than anything else. To that end, Ive been polishing the plenum and runner to a mirror finish. No rush on the project as Vette running so good under the current setup.l

The Miniram you pictured looks cool, but I couldnt justify the price. I bought a complete TPI setup from another forum member for $160 shipped, including injectors.

You have probably already figured this out, but be aware of the variation in the TPI setups over the years and between F-bodies and Corvettes. If you have pre-87 heads, look for a Corvette system as it will bolt to your heads. 87 and up F-bodies will have center bolt angle issues.

If I can be of any help, let me know.

Thanks Matt, and yes ideally I would like a GM TPI or equivalent, but am using conventional (aluminum) non vortex head so...

I was actually doing a google search and some were saying a throttle body on a single plane intake (direct port) was making good power over the above style manifolds. But as you said, the cool factor of a TPI. TBI on a single plane leaves a little to be desired in the looks department.

And beautiful article and write up. Love the tip about the '82 pump. Thanks for your due diligence! And while I too loved scouring the junkyards back in the day, those days are gone here in NJ. Few pick it yards and time.... never enough lol!

Any year Corvette TPI system will work, and 85-86 F-bodies . The fuel injection install was one of the most fun projects I've done on the Verge. The OD transmission swap was great to make the car more fun to drive, but the EFI was a fun puzzle to solve!

Programming the ECU was fairly simple with the new tools and software available. Tons of info on gearhead-efi.com.

Consider a GEN II LT1 intake conversion. Very similar to the mini-ram but less expensive. Third Gen . org has a lot of good threads and information on the LT1 conversion. Myself I don't consider the Ram type manifolds TPI induction as the runners on the mini-ram and LT1 intake are way too short to provide the same pulse wave tuning the TPI does.

Good luck.

Edelbrock has an LT1/4 style intake that doesn't need conversion therapy. Pro-flo xt

A friend of mine used the TPiS (brand) LT1/LT4 style intake on a solid roller 383. He built this thing probably 15-16 years ago so there wasn't many management systems out then, I believe he used an Accel management system. This is in a C2 and fit under a C2 hood, the car made 430 rwhp on motor and 600 rwhp on a 175 shot, all controlled through the ECM.

I think I'd likely use the same TPiS brand intake, but use Holley Dominator EFI or the likes to control it. Can't go wrong with any of the Holley EFI options.


The new throttle body systems are cheap, reliable and easy to install, like the Sniper series...a great option and simple to setup. Probably the easiest way to go these days.

I have an older TBI set up on my car and its great for what it is but it hits a power level limit quick and the only way to upgrade is a new $1000 TBI. The Ramjet/TPI/LT1 you can upgrade to bigger injectors to support higher power levels.

WOW! Talk about "cool factor"!! Would just hate to hear how much $ that cost! Any hp numbers? How about drivability? Definitely the look I'm after, just not sure I want to pony up the funds.... And Hogans has done a lot of EFI manifold R&D research with some top Pro Stock teams. Would love to hear more....

The 5.0 and 5.7 used different intake manifolds. The 5.7 manifold will bolt on older conventional heads. The 305 intake has revised bolt angle in the center location for the 305 heads. Factory TPI intake is good to about 4500 or so.

What TBI unit are you using?

Yes, it was not cheap John. I had the manifold made a few years back, I think that was about 3k. Then there's the throttle body, injectors, fuel pump/regulator/filters, plumbing and ecu. I'm not sure what it totaled to.
The engine is a 427 sb and dynoed 465/465 at the wheels. The drivability is good. Its got 3.9 gears in the rear and a 5 speed Legend transmission, this give it good performance with a reasonable highway rpm.

I don't believe that statement is accurate. The 305 and 350 lower intake manifold setups are the same, but vary based on year and model. Pre-87 units fit traditional sbc heads. 87-and up manifolds from Camaros and Firebirds have the newer bolt angle in the heads. Corvette aluminum heads never changed the center bolt angle,so the Corvette lower manifold will also bolt to traditional heads. If using a Corvette manifold, you'll need a block off plate for the rear EGR port that originally bolted to the exhaust manifold via tube.

Other differences in years are the MAP vs MAF systems, food start injecfors, etc.

As stated above, the manifolds 5.0 and 5.7 manifolds are identical, and this is one of the major factors limiting a tuned port to 4500 rpm. Others (in descending order) are internal runner size, throttle body size and injector size. The plenum must also be ported to match the larger runner size and the larger throttle body (and smooth flow). I have made all of these mods, and 'solved' the manifold base problem by using Vortec heads and mating them with a Scroggins-Dickey manifold base (I understand that the Edelbrock vortec base is similar). It will pull hard up to 5500-6000, which is as high as I am interested in going with hydraulic roller lifters

We used the manifold in the photo on a friend of mines 383 motors for a 28 ft Donzi boat. The lower part looked like it was based off an old tunnel ram intake. Port matched it to the heads I built him and it needed some port matching to the plenum. The engines both made just over 500 horse with about the same torque with a cam with mild duration and a wide LSA. They pull hard from idle to about 6000 rpm.

Mike

What heads are you using? If they flow anything at all, TPI might not be the best way to go as they're a HUGE air restriction, even fully ported. The 400+ HP TPI guys (and there's not very many of them) have to use fully ported plenums, aftermarket runners, aftermarket bases, descreened MAFs, and aftermarket throttle bodies.


Your options are: GM TPI (huge power and RPM limitations), ported GM TPI -slightly less power and RPM limitations but still significant, after market + ported GM TPI required for 400hp, Stealth Ram, TPIS MiniRam, or FIRST Fuel Injection giant TPI intake (can support 460hp unported).http://rcsracingengines.com/Perf%20C...evy%20EFI.html

The GM TPI options will either hugely limit power, or limit power some but cost a big stack O $$$$.
The Stealth Ram is pretty perfect and a very much like the long-runner LS intakes, in terms of power band - makes less low-end torque than the long-runner TPI intakes but doesn't restrain the high-end HP. -Won't fit under a stock C3 or C4 hood, though. It just won't. (Think of this as a really good dual plane intake equivalent in terms of powerband.)
TPIS MiniRam- Completely different. Personally, people shouldn't call this a TPI intake. This has a shared plenum and a front throttle body but the similarities end there. This is the "single plane equivalent" of the family. It's for high RPM usage and significantly hurts low-end torque compared to the long-runner (TPI/FIRST) and mid-length runner Stealth Ram. Big Stall, Big Gears, Big Cam combos. -It WILL fit under a stock hood. Cost is pretty bonkers for what you get, IMHO. Big power also requires that you clean it up / lightly-port it.
FIRST Fuel Injection: Looks like a giant version of a GM TPI. The runners are slightly shorter (19.5" plenum to valve vs 22" for GM TPI) but everything else just supersized which increases the RPM of the 2nd wave tuning. This is another torque beast intake, but it won't run out of breath until after 6,000 RPM on a 350 or right at about 6,000 RPM on a 383 (without being ported). $1,050 for everything except a few computer sensors and your EFI ECU.


If you buy a higher rise aftermarket hood the Holley Stealth Ram is an amazingly balanced choice. If a stock hood only, my opinion is the FIRST Fuel Injection intake (I've got one), ESPECIALLY if you want a torque-focused build. Ken @ First will CNC port the intake's to the Felpro gasket size of your heads for free upon request. (They're a rough port with a "Step" that you can then choose to smooth out if you want, or leave the step for a bit of anti-reversion dam.)

The stealth ram will have more HP @ 6,000 than a FIRST, as it's runner lengths are tuned for that RPM range, the FIRST will have more torque/hp in the lower and middle of the range than the stealth ram, but will be slightly below it @ 6,000. Your @ 0.050 duration should probably top out in the 2teens - 220s with a FIRST intake. The Stealth RAM I think will be happy into the 230s and after that you're in miniram / single plane territory.

A single plane intake with an elbow and a throttle body and EFI injectors welded in will have better cylinder to cylinder distribution than any of these intakes, though. Personally if you're looking for high RPM, don't even bother with the TPIS miniram unless you just can't live without the look; just go with a good single plane and throttle body injection (Holley Sniper) and keep some $$$ for something else if you want a high RPM motor.


Adam

On the definition of "Tuned-Port Intake":

ALL intakes are "tuned" to some particular RPM range, even dual and single planes, and individual stack intakes.

TPI refers to the GM TPI, long, curved runner intakes that try to use the 2nd harmonic wave (queue even more pedantic responses about how to count the waves in: 5, 4, 3, 2....) to build great low and mid-range torque at the expense of upper-RPM torque/HP.

Stealth Rams and TPIS-MiniRams aren't 'TPI" intakes (despite what the "TPI" in "TPIS" stands for). They don't have the big curved runners and don't have long-runners tuned for the 2nd harmonic wave (although I do think it's possible for a Stealth Ram to pickup both the 2nd and 3rd harmonic waves with the right cam timing and porting, if I remember correctly). The TPIS mini ram certainly doesn't focus on low end or mid range torque nor the 2nd wave. It's an oxymoron of an intake name.

People have started using "TPI" to mean "Any GEN1 SBC intake that has a shared plenum, front-facing throttle body, and port injection"; that's IMHO a terrible, nonsensical, and inconsistent definition that doesn't mean much.

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Adam

It's TPiS with a small i so I'm doubting the TPi in TPiS stands for tuned port intake. The TP might stand for Total Performance.