"if a FIRST base is available as a stand-alone purchase"

Ken sold me one.

 

BTW...I can't remember if I reposted this info in this thread....

The FIRST had a pretty good showing on the stock [L98] engine, but where it shines is on modified engines. Here's some numbers from a May 1991 Popular Hot Rodding article.

9:1 355 AFR heads hydraulic cam
RPM - FIRST - MiniRam - AZ Speed & Marine
2500 - 175 ---- 175 ----- 180
3000 - 237 ---- 222 ----- 238
3500 - 295 ---- 263 ----- 295
4000 - 350 ---- 300 ----- 325
4500 - 377 ---- 350 ----- 352
5000 - 388 ---- 375 ----- 350
5500 - 366 ---- 398 ----- 330

The FIRST made 443 TQ vs the Miniram's 395 TQ at 3500 rpm (+48)
The FIRST made 460 TQ vs the Miniram's 394 TQ at 4000 rpm (+66).
======================================== =====

If anyone has access to that article, you might look it up to see if/how much the FIRST intake was ported. If none (or not much, I have to think a bit more work could get that extra 500rpms reworked TPIs can easily touch.

I consider the LTx intake very similar to the MR power curve. And, if you notice, there's quite a bit more power in the mid-range simply by swapping to the FIRST. (17% more power at 4k rpms.) Consider other bang-for-the-buck options w/o cracking open a motor.

I also assume (since I've always owned a stick) that automatic's take some work to reconfigure their shift-point significantly above the 5000-5500rpm point. That's why the FIRST seems like a great bang-for-the-buck option to me. Especially if they still come with a larger throttle-body.

Maybe you (the reader) like the idea of gears better...or some other option. I'm just giving you something else to consider.

I can think of one other thought to end with....I was in C4Tech for 1yr before reading about this intake. With others were talked about daily, this one remains unadvertised. For 1/4m racers, I understand why. For street-builders (which aren't as common), I can't.

IMO, this is the best "answer" to Lingenfelter's superram. And, it's no secret not everyone is fond of it's issues either. For LT guys, all I can say is "Think LSx!".

 

[QUOTE=GREGGPENN;1577310026]BTW...I can't remember if I reposted this info in this thread....

The FIRST had a pretty good showing on the stock [L98] engine, but where it shines is on modified engines. Here's some numbers from a May 1991 Popular Hot Rodding article.

9:1 355 AFR heads hydraulic cam
RPM - FIRST - MiniRam - AZ Speed & Marine
2500 - 175 ---- 175 ----- 180
3000 - 237 ---- 222 ----- 238
3500 - 295 ---- 263 ----- 295
4000 - 350 ---- 300 ----- 325
4500 - 377 ---- 350 ----- 352
5000 - 388 ---- 375 ----- 350
5500 - 366 ---- 398 ----- 330

The FIRST made 443 TQ vs the Miniram's 395 TQ at 3500 rpm (+48)
The FIRST made 460 TQ vs the Miniram's 394 TQ at 4000 rpm (+66).
======================================== =====

I also assume (since I've always owned a stick) that automatic's take some work to reconfigure their shift-point significantly above the 5000-5500rpm point. That's why the FIRST seems like a great bang-for-the-buck option to me. Especially if they still come with a larger throttle-body.



On the 92-93 you have to change govenor spring or weights. On 94-96 its a simple reprogram of the computer.
By the way, do you have any hp nos. on the above post?

 

That is HP numbers. (notice the two statements about TQ at the end of the table.)

 

[QUOTE=93 ragtop;1577311006]Interesting graphs that I have never seen..... the First does look like it is producing a curve something similar to a Superram, which is a good thing. But not sure based upon that motor being a factory stock motor of some sort..... hence a cam/head combo not designed to go anywhere up in the rpm range and definitely a mis-match for that Miniram and even aftermarket tpi set-ups to a certain degree.

I think the question comes down to acceleration.... with your A-typical LT-1 or L98 owner who is going modify his motor with aftermarket cylinder heads, headers and a hyd roller cam in the 230ish area as so many do and run a gearing/converter combination that is a good match for the particular set-ups rpm capability...... which intake system would accelerate the fastest ?

My guess, if this question is answered, we would have all sorts of LT-1 & L98 owners jumping at the First Intake if it won the battle of acceleration.... which is of course, what we are all after.

 

Greg,
This exact posting is what concerns me about the First and what I plan on testing when I try it on my engine. The sharp drop in power after 5000 RPM is due to the runner length being 20" and the engine running higher than the third harmonic wave. The power drop is not related to it not being able to flow enough air. What I want to test is will the power come back up once the engine hits the second harmonic wave at approximately 6400 RPM.

FYI
The intake tract length of the LSX intakes is about 15" or the same length at the Superrram intake tract length. That is why the Superram works so well on the street; it is designed to peak around from 5300 to 5700 RPM.

I do believe the FIRST is a good street intake I just need to find out if it is a good street/strip intake.

 

In stock form, it's not the best 1/4m intake. With sticky tires, maybe an 1/8m setup. With significant modification like 89TA, I bet it's better than a SR. That's due to the base-to-head transition.

I don't see how you can take ENOUGH advantage of the second harmonic. In it's stock runner length, I think it's rolling off too fast.

 

"The sharp drop in power after 5000 RPM is due to the runner length being 20" and the engine running higher than the third harmonic wave."

The exit of the First intake manifold is around 1.95" CSA on average accounting for the radii. Do you think that might be to small considering the length of the runners? If one was to open it up to match the port of the AFR heads or slightly under and carry that CSA on through the performance might very well be a lot different in regard to the rpm range.

One more thing in general if the exhaust was "tuned" to fill in the gap between the 3rd and 2nd I think things would be different and there would not be much of a drop off. I have an intake system under construction that will test these theories. The total runner length will be 21 inches. Sometime after the Los Angeles Invasion we will find out. The intake manifold itself is currently over at Dr J's being opened up. The runners are virtually done. The plenum is 1/2 way done. So good progress is being made.

 

Hmmmmm, double post.

 

Below, you'll find another pic of the FIRST runners. You can see this owner (Z51L9889) had started on his siamesing. You can also see there's room for more of the partition to be removed. If you can remove about 3" of the divider, I think you're in SR territory -- but with a 20-30% bump in air flow. That's gotta make a difference on the ground!

Since these intakes have a "native" intake port that'll match up to 1206/1207 intake ports, you can put them on bigger heads. The question (in my mind) is how much above 300cfm can you get them. Of course, that's the range of heads with that size port, right?

For people interested in a SR-like powerband, I have to think the tube size, base transition, and ability to siamese provide some significant potential. For someone willing to cut/weld, I don't see why these runners weren't modified vs the SLPs (as 89TA) did. That's because there's NO WAY SLP runners can come close to the size of these nostrils!

Keep saying to yourself "300cfm out of the box!". Eventually, that should soak in!

 

I don't know if one could reach in the middle with a cutting tool but when I was doing some measuring on the runners it looked like a 1.90" ID was doable. It one was to make their own runners using 16 gauge 2.125" tubing with a 2.00" ID that appeared doable. That would support some serious horsepower.

I don't know if you could make a 2.250" tube runner fit. One would have to do some close measuring. If so that would support a big inch motor and a lot of power. The base is pretty stout and it might take a little welding to use a 2.250" runner.

Anyways a lot of possibilities with the First if one was so inclined.

 

As long as you don’t mind running what ever stall speed and gearing required,, similar builds,, the short runner intake making more HP at a higher RPM will always be quicker. For those that compromise on the gearing and stall speeds, it could be about a wash or the longer runner system might be quicker – depending on the build.

Which intake is “best” will all depend on the build criteria and compromises you’re willing,, or not willing to make. There’s just not going to be a “perfect” fixed length (or semi-fixed with siamesing) intake to fit every build. However, with the minimal cross-sectional capability of the FIRST in the 2.68” range (to put that in perspective the 235cc AFR heads measure in at 2.53”), it does open the door for use of a long runner system on rather serious,, and large builds.

The following are best overall time-slips, for a TPI/SLP, HSR, and FIRST intake run on the same engine/car,, all at the same track about 800ft elevation,, in the most similar conditions (HSR went 12.3s right at 110mph in 48-degree temps).

The engine is a middle of the road build that would make around 410-415HP on the dyno with a single plane carbed intake. It recorded 331RWHP @ 5850 with the HSR. 1986 IROC, 3450lbs with driver, TH350 (3-speed automatic), 3,000 stall, 3.23 gears, auburn unit, 26x11.5 ET Streets, 355 cid, 9.8:1 compression, Trick Flow G1 Twisted Wedge heads (245cf @ .500), 268/276, 218/228 – 110 custom (ground for carbed single plane intake) hydraulic flat-tappet .493/.502 lift with stamped steel 1.6 rocker arms, Hedman 1.625 shorty headers, 2.25” Y-pipe, no cats, single 3” exhaust, Dynomax Ultraflow welded dual outlet muffler. 52mm BBK (around 780cfm) used for the TPI/SLP combo and HSR, FIRST came with its own mono-blade 780-800cfm T/B. Used the stock 350 MAF chip, tuning consisted of best base timing and fuel pressure for best ET,,, set at the track.

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 to 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, 5800/5600 rpm shifts, foot-brake 1800 rpm, near full throttle launch, moderate traction problems (hard, but not impossible to launch)
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

I personally liked the FIRST for this combination although I did not dislike the HSR. When playing around,,, the midrange rush from the FIRST gave the illusion of driving a much quicker car (about like my SS with a 406 and 3.89 gears when it was running 11.8s). The FIRST was hard to hook on the street tires,, where the HSR was manageable. The HSR responded about like a Edelbrock Performer RPM with a 750 DP and felt like a mid-12 car,,, which is not bad. However,,, I really liked that the car would turn basically the same ETs shifting at 5800/5600 with the FIRST as opposed to 6400/6200 with the HSR,,, just depends on your preference. Can’t really go wrong with either intake, but you gotta love the idea of popping the hood and passing off one of these FIRST intakes as a stock POS TPI.

 

1.9" is doable. It's a little tricky,,, but once you open up the ends to 1.85" and larger you can get to the middle of the runner and shape it with a medium large oval burr on a 6" shank.

 

There you go folks. If one had the money and followed that up with an "Extrude Hone" look out. Even if you did not, look out anyways.

 

Got just the carbide for that one, 3/4" in dia

 

for cleaning up the inside of a runner, you can put pots/pans steel wool on a flex shaft and use a drill to clean out the inside if a runner. I did this to remove carbon and ended up removing casting flash with a dremel, then use the steel wool to polish the runner. it looked similar to my extrude honed super ram runners. I just dont thing it made them larger, unless you did it for a week straight.

 

I used (harbor freight) 1.5" wire wheels on a solid bit extender. That let me press laterally to "dig" off the alum faster. I constantly reciprocated the brush up/down the walls to avoid digging in one spot. Then, I finished with flap wheels. For the siamesing, I also used a carbide burr on a 6" shaft.

Ended up with this result on SLPs -- which is what I'd shoot for as mimimum siamesing with the FIRST to hit 5500rpms (vs MR/LT intake). And, if you can hook it up, accelerate faster for 55-5800rpm shifts. I wouldn't be surprised if this level of siamesing/porting got you into the 320-330cfm range. (Compare that to the best SR flow numbers you've seen.)

 

Interesting results.... based upon mph and the set-ups, not too far from predictable. I do not know the HSR all that well, never raced it, but I would have thought it could 60 ft considerably better than 1.80 .... however once I look at it, the 3.23 + th350, which I believe has a 2.52 1st gear.... hence 3.23 x 2.52 = 8.13 final 1st..... which would be equalivent to a 700R4 with a 2.65 gear (3.06 x 2.65 - 8.13)....thats not much gear.... those other set-ups probably do not need much gear, but I suspect the HSR does, but not sure. I'm guessing it seemed like it was taking forever to build rpm in 1st gear with that combination.

As a comparison, back in the mid 90's when I first started racing my C4, I added Dart 2 cylinder heads out of the box(226 cfm on a bench), 74211 LPE cam (211/219 - .503/.525 at the time), 1 3/4" headers, stock Y pipe, stock 85 GM 12" converter, which in 85 is basically equalivent to the S10 converter and was considerably looser than other year C4's, Accel base, Accel long tube runners, unported, ported plenum, 52 mm TB, 3.07 gears. I didn't weigh it back then, but at that time, it was 100% stock weight, front fatties, full a/c and heat.... plus I weighed 270lbs with helmet, hence I was probably a raceweight up around 3400 lbs at that time.

200 ft track, in 80 degree, dry air. (Socal track) It was always within a tenth or so of its below best thanks to the consistent California air. I bracket raced all combinations considerably.

1.72 60 ft - 12.42 @ 108 mph

Then threw the long tube runners out and switched to un-ported Superram, nothing else changed from above.

1.68 60 ft - 12.12 @ 111 mph

That was 2nd time out. Went to 383 shortly after that, ported the Dart 2's (Upped it to 256 cfm by Bob McCray), swapped to the 219 cam, also went to a 3000 rpm Vig.

1.54 60 ft - 11.55 @ 117 mph

Switched to AFR 190's unported, but did have a 5 angle valve job.

1.52 60 ft - 11.32 @ 119 mph

Have a 436 sbc now.... thus not relevant.

Nothing above is great or anything, others are doing better nowadays with similar set-ups..... but, for me to ever consider a First Intake, the above is the minimum type of performance I would look for out of it in such a docile tame street set-up. I'm not sure it can do it.... but it does look a little bit promising, primarily because of your results... its not the et, but the spread between the et's. But do need to see a few more get serious with it and try to dial in an et.... I think if we could see some C4's with 350's breaking into the 11's with it and some 383's going deep 11's would be pretty good with todays cams/cylinder head selections and make the First a welcomed and viable option.

The one thing that I am trying to figure out, somebody had said it has been around for 20 or 30 years, yet we really do not have much on it.... I suspect people are not running them simply because people did not know about it. (I didn't, and I thought I knew every intake choice for the last 10 or 15 years) Maybe there are some results out their we don't know about it.... not sure.

thanks for sharing !

 

Thanks for being able to look deeper than just the bottom line ETs/MPH. I was never happy with the way the car ran - I used to be able to get 13.4s out of cars like the IROC,, back in the late 80s and early 90s with little more than free mods. I got one to run 13.2s (3.23 gears and 26x8.5 slicks) with the same "free - mods", a ported exhaust manifold, gutted cat, and a single in/out Flowmaster (they flow much better than the dual outlet Flowmaster on the f-body). I’m near positive that thing would have cracked into the 12's with a little more converter on a cold day/night. So,, I was not overly excited that I actually had trouble cracking into the 12's with heads, cam, aftermarket runners, and a fairly healthy stall – regardless of the temperature.

Anyway, yes, the difference in MPH between the intakes says a lot. You picked up .3-seconds and 3mph with the switch from the long tube runners and plenum to the SuperRam runner and plenum. I picked up .35-seconds and 2.3mph from an extensively ported stock base and SLP runners (which I would venture to say flowed at least as well as a box stock aftermarket base and runners) to the FIRST.

What was the most impressive to me about the swap from the ported TPI/SLP combo to the FIRST,, is that I had taken the runners on and off,, taking .5" out of the divider until the ET and mph leveled off. I put a tremendous amount of time and effort into getting that combination as right as I could (and I’ve been doing this for a while). Throttle response was absolutely violent,,, and could spin over the street tires with a hard stab while in 2nd gear (1.52 ratio). Even with the weak gearing,, with that stall speed so close to the peak torque of the TPI/SLP combo,, it was basically impossible to get a good launch with the stock suspension. That's not an excuse, just that the car could have ET'ed a little quicker. Never-the-less (pick any number of the reasonable explanations) the box stock FIRST ran a better ET and MPH.

Also, the FIRST originally hit the scene around 1987 or so as the AirSensor Research’s “TPI” unit. They advertised in a couple magazines and Summit,, back when they attempted to build complete engines,, used the “FIRST” on their “TPI” engines – which were VERY expensive (explained later). Neither lasted very long and the rights to that intake was sold to Electromotive - they did even less marketing of what they called (minus the F and the T) the IRS (Individual Runner System). However, they did make their way into a couple dyno shoot-outs back in the late 80s and early 90s and did very well,, producing similar results to the SuperRam.

I wanted a "FIRST" back then,,, but the “problem” and the reason you didn’t see many back then is they sold for around $3000 with the electronics. I tried extensively with both AirSensors and Electromotive to buy the intake without the electronics and neither would budge,, both saying considering how advanced the intake was,,, it HAD to have their electronics,,, lol. Needless to say,,, when I found out FIRST Injections bought the old Electromotive stock and casting rights and started selling the intake system with and without electronics,,, I couldn’t wait to get one. I just hate I've had to put off my project for so long. There's a lot of potential locked within these intakes with porting - Allen with his 420rwhp 369 has scratched the surface, but I think there's definitely more to come.

 

Ahhh.... with you mentioning that they wouldn't sell it without the electronics rings a bell, I remember it. Although, I hadn't realized the runners & base were any different than your A-typical long tube set-up, thus didn't pay attention to it.

I think the lesson is, knowing your market and appropriately marketing your products to it is extremely important. They should have been the outright leaders in the longtube TPI market, instead, due to not knowing what they were doing, they're probably dead last in sales. However, it sounds like the new owners have a better understanding and that might change.

With those old HP tests you were talking about, is there a link or anything to them ? I know about the Superrod test, but I know the First wasn't part of that. Not aware of any other substantial TPI publication tests.