Hi all, want to get some feedback regarding Air Intakes for my 91 stock L98 with Auto-trans What I found so far and interested in are the following 2:




anyone installed any of these or have a good experience which way to go. Which is better performance, easy to install and clear the stock hood? (Any other brands recommended)
there is a big difference in $$ between the two but let’s put this a side for now ...

I’ll be adding Headers and exhaust soon and maybe 1.6 RR...

so I appreciate any feedback
TIA

 

The stealth ram does not normally fit without modification to reduce its height.

 

The very short version is that the Stealth Ram doesn't fit under a stock C4 hood, but it performs great. Whereas the FIRST TPI intake has a fairly hard RPM limit due to the length of its runners, and that will prevent you from realizing all the power potential of other mods you do down the road. For example, if you decide to go with a "hot cam" package in the future, which will raise your power band to 6000rpm or above, all TPI intakes will keep it from making power up there. This is regardless of runner cross sectional area and has nothing to do with flow bench numbers - it's all about the runner length on a resonant system like an engine intake tract. Also, TPI-length intakes don't make more "torque" off idle, like most people think. They only create a spike at around 2500rpm and only have that advantage over short-runner intakes for about a 1000rpm window.

The "easy button" solution for C4 intakes is to get a Miniram, which fits under the hood easily and doesn't limit power. An LT1 is very similar, and I believe it can be adapted to an L98. Cuisinartvette was selling three of them very cheap in the C4 Parts For Sale forum recently. He can tell you what is needed to adapt them to your engine. I have no idea if he'd ship to Dubai, but that would be an interesting story to tell. At the prices he's asking, you could buy at least two and then if you mess up the mods on one you can try again on the second one!

 

I am happy with my Edelbrock Pro-Flo XT. It fits under the C4 hood with no problem.

 

Thanks guys, I’ll take these notes and if more feedback received ... and I’ll do more research to decide.
as for the mini ram I don’t think new is available, Right? But I’ll keep looking as I’m overseas so it won’t be that easy to get a second hand...

 

I came across this one while researching but according to their site it’s for SB up to 86 model! Is that true?
which part no. You have and any additional parts or mods required? Or just bolts on...

TIA

 

mini ram still available new tpis.com

 

For an automatic street car the First will be more fun. Stealth doesn't fit under hood as described above. Mimi-Ram makes things much easier to work on and the way to go if you have plans to build a stroker in the future....

 

I have a FIRST but I haven’t put it on yet, I will be as soon as it gets warm enough to. I think I will be happy with it, it is still good at 5000 rpm or more and the stock intake stops at 4500 rpm from what I’ve heard, plus it should make more power throughout the whole rpm range. It won’t flow in the high rpms as good as the pro flo or mini ram though. But these cars were built with long gearing to run in the low rpms and the FIRST is better at low rpms so I think I would like the FIRST better. Plus it looks good in their painted version. here’s mine, they took this picture before they added the throttle body.

 

wow that looks wicked
And it’s close to the stock in shape
how much did it cost you?
does it come all with the parts as in photo or you need to add additional?
cant wait to see it mounted!

 

It came with all the parts in the photo plus the throttle body. They sent me that picture before they added the throttle body. I have had it since December. It cost $1200 plus $60 shipping. It’s expensive but it does come with the fuel rails and throttle body too and most other intakes don’t. Plus you can fit the big cap distributor with this one and with others like the mini ram you have to buy a small cap distributor. Yeah it’s close to the same shape as stock and I like that part because the tpi looks good, it just flows bad. This one when sitting next to a stock one is giant though, the runners are really big and all the ports are bigger than stock. I will have some pictures probably the end of March or April when I get it installed. I still need to get injectors, an adjustable fuel pressure regulator and new sensors to use.

 

thanks and good luck 👍🏻
looking forward to see it mounted and running....

I’m interested more in this one now

 

Why not use an LT1 intake, it would be a lot cheaper way to go.

 

Guy in this video explains why it isn't worth it

 

https://www.edelbrock.com/pro-flo-xt...fold-7137.html Another option that will fit with a tad bit a trimming to the Throttle body lip but will cost as much as the TPIS Min-Ram by the time you buy all the hardware and the Throttle body.

 

It will only make a little more power for a roughly 1000rpm range centered roughly around 2500rpm. At all lower RPMs it's no different than a short-runner intake, and at higher RPMs it's worse.
But let's be clear: the longer gearing may help stretch the MPH range of each gear to match the lower-geared, short-runner engine; but it will be slower to accelerate throughout that MPH range because it's making less power.

I'm not trying to be argumentative, because I know we discussed this in your thread. I want the OP of this thread to have the full scoop, though. For similar outright costs, the Miniram is a far better bet than the FIRST if performance is the goal. Two things are not debatable: 1) the FIRST is the best of all the TPI-like intakes out there, and 2) the FIRST intake looks awesome.

PS - the Edelbrock Pro Flow is interesting. I know nothing about it.

 

I know someone with that intake, he used an ls style throttle body that is a lot easier than making the stock throttle body work. He is really happy with it, I planned on getting the pro flo until i found the FIRST and decided on it.

 

It's obvious you are biased against the FIRST and favor the MR. As such, I'll conclude you enjoy/target 1/4m racing as much as anything. That said, I thought you mentioned auto-x as a hobby too. One of our "historical" members (mcrx...or something like that) ran both an HSR and longtube setup in auto-x. I'm not familiar with auto-x classes but he started with the longtube, converted to HSR, then went back to longtubes. He won way more races leveraging "power under the curve" of a lower-hp/bigger torque setup. That's why he went back.

Before I selected a longer-runner intake, I communicated extensively with a member more visible in 3rd gen. "BADSS" was in the biz of engines earlier in his career. The following review of an mega-ported SLP, FIRST, and HSR factored heavily into my own intake selection:

Back in the late 80s a company out of Seattle, Washington called AiRSensors introduced an EFI product line called Fuel Injection Research and Technology Systems (F.I.R.S.T). The FIRST product line was comprised of their flagship “TPI” system - hence the reason “FIRST” is cast on the plenum and TPI is cast on the throttle body plate. The FIRST lineup also included a “MultiPoint” single-plane intake system, much like the Edelbrock “Pro-Flo” EFI and a “SinglePoint” throttle body system, similar to the Edlebrock “E-Street”.

They were well ahead of the times, but very expensive and not available without their electronics that utilized a 4” Air Mass Sensor. In the early 90s AiRSensors sold the TPI intake rights to Electromotive where they machined off the F and the T on the plenum and marketed it as an "Individual Runner System" (IRS). The Electromotive IRS intakes were even more expensive because they added an ignition system to the package. I’m pretty sure I wasn’t the only one that tried to get both those companies to sell me the intake without the electronics,, and I’m sure others felt just like me when they refused to sell just the intake. Best I remember it was around $2,700 from AiRSensors and $3,000 from Electromotive – that was crazy high back then,,, and the reason you didn’t really see any of them.

I was glad to see Ken of FIRST Fuel Injections resurrect this intake system and sell them with and without electronics. I’ve also heard FIRST is looking into siamesing the runners. I just wish they would take the creases out of them to look like the SLP runners so one could siamese them to whatever effective length you wanted!!!

As for comparisons, I really hate chiming in on these FIRST posts because it makes me look like some kind of poster boy for the FIRST. However, I think I'm one of very few people that has tested the FIRST against a HSR. So, I do believe I have a little better insight than most when it comes to the FIRST (the only thing in common it has with the stock type TPI intakes is it looks a lot like it). Anyway, whether the FIRST or any intake for that matter is “best” for a given combination relies solely on the intended use and the amount of compromises one makes for drivability and/or street manners. There is not a fixed runner intake made that will work “best” for all engine/car combinations.

TPI / SLP Intake (fully ported GM base and ported SLP runners to the 1/2 way point)
88*F / 29.92 barometric pressure / 86 percent humidity
8* initial timing, VERY heavy burnout, foot brake off idle, staggered throttle launch (pumping the gas well past the 60ft mark), 5,500/5,500 shifts. Practically impossible to launch with the base timing at 10-degrees – dropped timing 8* to help hooking, 6-degrees helped 60ft, but really killed MPH
60ft------ 1/8 ET -----MPH ------ 1/4 ET ----- MPH
1.873 --- 8.268 ----- 83.94 ---- 12.953 --- 104.40

Holley StealthRam (minor clean-up, rolled the top edges on the base intake)
85*F / 29.92 barometric pressure / 89 percent humidity
16* timing, 46 psi fuel, 20 psi tires, heavy burnout, foot-brake 1,800 rpm – full throttle launch with heavy burnout, 6400/6200 rpm shifts. A blind monkey could launch the car after a decent burnout,,, no traction problems.
60ft------ 1/8 ET -----MPH ------ 1/4 ET ----- MPH
1.803 --- 8.133----- 86.27 ---- 12.673 --- 107.84

FIRST (box stock, even used the older gasket that overlapped the runners)
83*F / 29.92 barometric pressure / 84 percent humidity
10* timing, 42 psi fuel, 20 psi tires, heavy burnout, foot-brake 1800 rpm, near full throttle launch, moderate traction problems
60ft------ 1/8 ET -----MPH ------ 1/4 ET ----- MPH
1.707 --- 7.992 ----- 85.53 ---- 12.599 --- 106.70

--------TPI/SLP – HSR -– FIRST
60ft --– 1.873 – 1.803 -– 1.707
1/8 ---- 8.268 – 8.133 -– 7.992
MPH -– 83.94 –- 86.27 –- 85.53
1/4 –- 12.953 – 12.673 – 12.599
MPH – 104.40 – 107.84 – 106.70

For a “driver”, I preferred the FIRST intake. It made a lot more midrange power and made the car feel like it was a much bigger and more powerful engine while playing around – MUCH more fun to “drive”. However, the HSR was much easier to launch and would have been my choice if I were more interested in racing the car than driving the car – I couldn’t mess up a launch at the track with slicks, just heat the tires and floorboard it. Now, I must add, once I got the tune right on the HSR it wasn’t what I'd call unresponsive – I’d compare it’s power band to a good dual plane carbed intake in the lower RPM range and a good single plane in the upper end. However, again the FIRST ran near identical times on this combination and I much preferred it over the HSR for its intended purpose.

I will also add that mid-length superrams put the gen4 SBC on the map (by Lingenfelter)...and that LS engines use a mid-length runner system over the short-style of the MR. More so for tall-gearing but really for any, that mid-range bump in power IS useful for street-driven cars -- and may even bump sales with the impression of more power. So, there is a case to be made for running a longer-runnered intake. The FIRST has been closely compared to the SR -- which may be the best combination of runner-length designed for the SBC. Again, it was Lingenfelter's choice too -- and used heavily in 80's-90's racing. To me, it's unmistakable that BADSS preferred the FIRST for a street-intake. I understood why.

The difference isn't really 1k rpms worth of the powerband. Plus, there are things you can do (especially with camming) that boost/extend upper rpm range for a long-runner intake. And, the larger the tubes, they higher the ceiling -- as flow overcomes reversion.

In another 3rd gen post, BADSS includes a bit more -- including shift points:

I liked the StealthRam when I switched over to it,, but missed the midrange rush of the old TPI - although I did like how the car could hook decently on street tires,, something impossible to do with the old TPI/SLP combo,,, and how well it ran from a kick. The FIRST is middle of the road,, but that's not necessarily a bad thing. It moved the power band up a few hundred RPM compared to the fully ported TPI/SLP combo,,, but not as high as the StealthRam.

Power band wise:
TPI/SLP - off idle to 5500 rpm - high-12.9s@105mph
FIRST - 2000 - 5800 - mid-12.5s@107mph
HSR - 3000 - 6400 - low-12.6s@108
ETs are for similar conditions with temps in the high 80s

To help with the comparison, a buddy with a 13.0 second LS T/A would pull ever so slightly away from me with the old TPI/SLP combo from a 60mph kick. I could blow his doors off with either the HSR or the FIRST - with the HSR being a steady even pull while the FIRST would really put it on him on the initial hit and kinda tapered off a bit. That same 13.0 car could hand over the TPI/SLP combo on street tires,, bad,, I could not hook the thing. Again,, with the StealthRam and the FIRST I could flat blow his doors off,,, but the FIRST was harder to hook. Like I said,, it all depends on what you're looking for. I never ran a ported FIRST on the IROC, but would have expected about a .12 reduction in ETs over the box stock FIRST with relatively minor port work / clean-up. Not that it's bad out of the box,,, it's just sized to a stock exit,, and it turns down into it. The injector bumps are also quite large and can be dang near flattened out.

I've made this statement a few times over the years and it still holds true. If I raced the car more than I drove the car, I'd pick the Stealthram - put some heat in the slicks and foot to the floor at the track. It was hard to mess up a launch. If I drove the car a lot and raced it occasionally, which I did, I'd go with the FIRST. It rolled off a little of the initial hit at launch making it a little easier to hook than the TPI/SLP combo, but it was manageable,

Another thing to consider is that the FIRST ran well with the stock MAF tune with a couple pounds added with the fuel pressure regulator and a couple degrees bump of the base timing - can't say if that would be the same with a speed density system. Regardless, the HSR requires a lot more tuning to get it to perform decently - have to add a good bit more timing compared to a long runner tune and have to mess with the tip-in tuning or it'll feel a little sluggish. Definitely need a custom tune with the HSR.

To me, there was/is appeal in making more power in the rpms I drive more often. I don't race. I also liked not having to worry about running to redline to leverage WHERE power is made -- which spoke to my desire for longevity. Specifically -- between the FIRST/HSR, BADSS had only about .1th difference in trap speed between the two intakes. It was hard for me not to notice the difference in 1/8th mile times too. The FIRST was faster...and...BADSS hadn't ported it yet. Yes, it's also obvious you have more speed "on the backend of the track AND that the HSR would win all 1/4m races. Between and HSR and a MR, I don't believe that answer is clear -- from other posts I've seen. Because of LS intakes and the rich SuperRam history, I would choose an HSR over a MR. And, I would do it for the same reason BADSS recommends the FIRST over the HSR -- midrange power.

In the TPI shootout article, "Ten Times the Torque", a TPIS large-tube intake holds clear "midrange" advantage all the way from 2500-4500 rpms. (You can't determine below that because it wasn't measured. (Typically, dynos reflect that engines are "revved" to launch 1/4m races.) That's a bigger advantage than indicated by Matt's "Let's be clear" post above. So, on that, I call "BS" especially when a FIRST has been shown to perform even better than the TPIS large-tube variety. That doesn't mean I will dispute a MR's advantage in the 1/4m OR it's ease in changing injectors. For the lion's share of my driving, I stay well-below the 85mph trap speed's of BADSS's review and I don't hit WOT very often either. That "modest" 2k rpm advantage is enough to cover most situations. And, compared to a C4 ZR1, my 383 puts out up to 100ft/lbs more torque. Even for common, everyday activities like downshifting one gear, I land in the rpm range where the extra torque provides an extra enjoyment. You know...2500rpm...and up. In my ZF6 car, that makes 5th seem like 4th (non-OD), and 3rd pull like 2nd. I can say it feels like I'm driving something bigger -- like a 427/454. Plus, compared to my SUV, it's still (by far) my "economy" car with the ability to hit 27-28mpg on the hwy.

My whole point isn't to say a MR won't be faster. Drive it in 1st, 2nd, 3rd, etc... in the upper rpms -- to redline and it will (as stated) put out a bit more power. Dropping another gear (2 gears) -- to leverage higher rpms can represent additional advantage -- when you consider torque-multiplying of gears. You just have to decide where you want power and how you will use it. If I drove an automatic, I'd likely be more inclined to use shorter runners. But, I don't. I own a ZF6 car and find intakes (like the FIRST) to be "just what the doctor ordered"....especially when it's for everyday driving around town.

Disclaimer: I run a mega-ported SLP setup...which shows I'd likely be "even faster" by converting to a FIRST. I also own an HSR (which will fit under my hirise hood). I've had it going on 10 years. The biggest reason I've never put it on -- is the description provided above. I drive "on the street" and feel like I'd miss midrange power and want it back....even if the HSR was clearly faster above 4500 rpms. Let's just say -- without making a lot of noise -- I can maneuver through traffic quite easily. In some ways THAT also has it's appeal since I'm running side pipes. I've owned my car since 1999 and have never gotten a citation. Being a black car helps.....a lot.

 

superam get no love

 

I've had the SR, AS&M large tubes, and the mini. Mini has been my fav for a bunch of reasons and the fastest.