bamaboy0323

iTrader: (1)

After taking MoJoe's advice I had my engine measured. Just a street car with HP goals 320-350rwhp 375+wtq

I will be running at 10:1-10.25:1 on my 350 with a FIRST intake.

I've been going back and forth as to which heads I need to get. It's between the Profiler 185's or 195's or AFR's 195's. I really want to run the CC503 cam and all heads have good flow with 1.6 rockers and puts it at .537/.544 lift or the 268xfi at .570/.565.

Would I get good power and torque running a 180cc head with a .500 ish lift cam with the FIRST? Say the Jegs/Profiler 180cc head?

Thanks

TORN

iTrader: (17)

Don't waste your money buying a FIRST injection system if you only want to make 350 HP.

mrestrictrplate

iTrader: (2)

I'd put the best intake I can on these cars. I've seen alot of builds hoping for 350 or 400 hp dynoing at 250 range on this site. I'd fish here and see some proven combos. Alot of knowledge here.

bamaboy0323

iTrader: (1)

I already purchased the FIRST lol

bamaboy0323

iTrader: (1)

I've looked for FIRST builds on a 350 and haven't seen many. Most are on a 355 and up.

sofakingdom

iTrader: (1)

355 IS a 350; it's just had the first episode of maintenance done to it.

You probably won't see many FIRST builds for acoupla reasons; one, it's a relative newcomer, and two, not many people want to build long-runner setups anymore, for obvious reasons, so there aren't a whole lot of em out there. You're a bit more "on your own" than you would be with some of the more popular ones like the Stealth Ram for example.

375 ft-lbs to the wheels out of a N/A 350, in ANY overbore, is not realistic. Torque is kinda basic... you put x amount of air/fuel mixture in a cyl, you ignite it, its pressure increases to x psi from the heat, it pushes on a piston of x area thereby producing x pounds (psi times area), it rotates a crankshaft using a lever arm of half the stroke, that's how much torque you make. The shape of the intake runners doesn't affect it, beyond the degree to which they create a more dense cyl fill; and since at peak torque even a stock motor reaches around 90% of "theoretical" max, i.e. atmospheric pressure (the term we call "volumetric efficiency"), there isn't a wholehelluvalotta room for GIGANTIC improvement in it. By raising the compression above stock, and by tuning the intake (as TPI does) to employ the inertia of the air in the intake runners to pack the cyl as fully as possible, you can get closer to 100%, and maybe a bit over 100% in a narrow RPM range only, but that's about all there is available.

A well-tuned free-flowing engine with a compression ratio that will allow it to run on pump gas is capable of around 1.25 ft-lbs per cu in. For a 350, that gives you an ABSOLUTE MAXIMUM POSSIBLE torque, at the crank, of around 435 - 440 ft-lbs at the crank, which of course assumes ABSOLUTELY PERFECT optimization of EVERYTHING. A feat rarely achieved to say the least. Then after drive train losses of around 25%, expect around 330 ft-lbs at the wheels. And that's only the PEAK #, at whatever RPM the intake, exhaust, cam, head ports, etc. result in the engine's MAX efficiency; it will be lower at all other RPMs.

An HONEST (read: not Southern California) dyno can be a truly humbling experience. Of course ANY operator can inflate the "correction factors" and come up with YOOOOOOJJJJJE numbers, like someone on here had happen: they put a TPI car, CA emissions compliant, on a dyno in LA or Orange County and came up with like 400 HP, then posted the dyno sheet, on which the correction that had been applied was like 5500 ft above sea level. Once the "accidental" correction "mistake" was taken out, the car turned out to do the 265 or so that was expected... but the owner SURE WAS disappointed. He had several $$$large in the motor and was expecting somehow that receipts = HP in some kind of direct relationship I guess. Unfortunately it doesn't always work that way.

I once pulled my car onto an HONEST one, where I saw the altimeter and corrections with my own eyes, right behind a pretty much gutted 1st gen race car, still mostly steel though. That car had a 454 with a Comp 302 Magnum cam; not sure what heads. (it was a long time ago) Obviously not a "pro" car, just a bracket racer; but still. It was a reasonably successful car that ran pretty much right on the index for the class it ran at its "home" track, which if memory serves was 11.something. It did 330 HP and 330 ft-lbs to the wheels.

Butt anyway... how long are the runners in that intake? That's going to determine the RPM that it makes power at. I'd suggest starting there. Then pick a cam that takes advantage of what those runners give you. Don't try to do it like you'd do a carbed motor with a single-plane intake; won't work very well.

Orr89RocZ

iTrader: (20)

180's likely give you more torque than the 195's but the 195's would be capable of slightly more peak/top end

I'd run a xfi based lobe on a 108-109 lsa and let it eat. 218-224 or custom 222-226 duration range is about right for the first and either head. Tight lsa will compliment the shorter rpm band of the tpi and build the torque you want

Tibo

iTrader: (15)

I think the FIRST setup will do better in 1/8 mile distances so I would stick with the 180's. 195's with the 224/230 duration might be too much RPM for the FIRST setup. Definitely use lower gears, probably stock would work with a good suspension setup and street legal sticky tires like the Nittos. That'll be about the only way you'll keep traction. I had the LT4 hot cam in a 355 with 195 trick flows and peak power was right smack at 6000 rpm and peak torque at 4000. The 224/230 should be really similar, is the FIRST setup on a 350 meant for peak Horsepower at 6000? That may be the most important question to find a reliable answer for.

Orr89RocZ

iTrader: (20)

It can support hp in the 5500-6000 rpm range. The cross section of the port and runners are large enough

Tibo

iTrader: (15)

Well then give it a whirl.

sofakingdom

iTrader: (1)

It's not about "cross section"; it's about length.

Just like a musical instrument. The pitch (frequency, RPM) isn't determined by the diameter; it's determined by the length.

TPI's runners for example are about 22" in length, which results in its "tuning" effect - the musical instrument behavior - reaching its peak at about 3600 RPM and then rapidly falling off above that. Physics would predict that the FIRST system will behave similarly, at some RPM determined by its runners' length.

Once you know the RPM range that the intake will force the engine to be most efficient at, choose the parts around it to optimize THAT, not try to fight it somehow. (i.e. with heads and cam that DON'T support peak power at that same RPM but rather defeat the strong point of the intake, and likewise the intake defeats the strong points of the heads & cam)

bamaboy0323

iTrader: (1)

Thank you all for great advice. I actually ordered everything already. I went with the profiler 185's with the cc503 cam with 1.6 rollers. I hope i didn't make a big mistake.

Orr89RocZ

iTrader: (20)

Let me ask this question...

22" straw, vs 22" 3" exhaust pipe. Which is easier to breath thru? Think of how air flows and behaves.

There are several harmonic levels at play that vary in lengths, however to support the power you need flow which comes from cross section

Tibo

iTrader: (15)

Sounds like we have some difference of opinion. I did a quick internet search (limited myself to 10 minutes since I have no dog in this fight) looking for people posting actual numbers for a FIRST intake and only came across this: https://www.thirdgen.org/forums/tpi/...o-results.html

Although his cam is smaller (212/224) he talked about power dropping off after 5000 RPM.

Also found a youtube video of a 383 (unknown cam and heads) with a FIRST making max power at 4500.

It's looking less likely that the FIRST will be well matched with a 224/230 cam but without any readily available results it may just be an ongoing argument. Post your dyno results!

Orr89RocZ

iTrader: (20)

His cam is too small to support more rpm and the twisted wedge heads werent comparable to what the OP has

The op will be happy with the 503 cam and 185 profilers.

Pipemax will calculate induction system lengths based on 8 harmonic levels. Typically most intakes land in the 2-4 harmonics. Single plane intakes are usually around 9-11" can be 3rd or 4th harmonic. The 2nd is long, 19-20" level for a 355 at 5800 rpm but in addition to this, you need a plenum runner min cross section of 2.1-2.3 inch sq. long small diameter tpi runner wil not support the flow for higher rpm tuning. Big tube setups usually do have abit more flow to support more hp and alittle bit more rpm

You'd have to measure the first to be certain but a combination of length and runner flow area will go a long way to keep hp going in the rpm range. Bigger cam will help hang onto that power without dropping off. This is more area under the curve and extends shifts, gets better et.

Also look into 1989gtatransam's tpi build threads. He did a 369" motor with first base, and i believe 20" long total induction length with custom huge runners and made hp to mid 6000's rpm

sofakingdom

iTrader: (1)

Yes straw size will influence how much air can be drawn through the straw.

Doesn't change the fact that a tube has a resonant frequency (same word as "RPM") that is dependent on its LENGTH, not its diameter. IOW if a runner is long enough compared to its diameter to act like a tube, it will exhibit tuning effects.

In the case of a runner in the 20"ish neighborhood and of any diameter that will realistically fit on a small block Chevy, that resonant frequency is going to put its torque peak (cyl fill reinforcement) at somewhere around 4000 RPM, just like TPI's 22" overall runner length creates a resonant frequency (optimized RPM) of 3600 RPM. Then of course torque falls off RAPIDLY above that, reaching a point of DESTRUCTIVE interference, rather than the CONstructive type that occurs at the torque peak.

It might "make hp" up to any random point, but the car will usually go MUCH faster if shifted before that, because even though it "makes hp" up to whatever, it makes MORE hp at lower RPMs, before the torque curve craters.

You don't happen to recall what part of the country the "6000 RPM" build was in, do you?

Orr89RocZ

iTrader: (20)

Lol california

I am sure you are aware of it and it did work as it was dyno'd at a respected builder shop joe sherman

The best system is going to be a shorter runner for high rpm use. Packaging concerns underhood is the reason why

But yes there are several harmonic orders that can tune for an rpm band and those occur in a variety of tube lengths. The theory does work if you can design the manifold without compromises, which in our cars theres always some compromises. Bigger diameter tubes at same length will most always support alittle more rpm because of less flow loss on a given engine.

Heres some good discussion

http://speedtalk.com/forum/viewtopic.php?f=15&t=37899

cardo0

I like that cam for your FAST intake. It should spread the power band out and not become too peaky/punchy. Much better for the street manners and just as much fun. U gonna use up tires as fast as u can buy them. I dont think u will gain much with 1.6 rockers and it will only shorten your vlv spring life. U have generous lift as is and 1.5 rockers will be good enough but u do need roller rockers.

Now becareful w/Profiler heads. IIRC those are budget heads and to get them to even work u need to have a cyl head shop check them out - seats, guides, vlv seals and maybe even springs. But once set up correctly they make as much pwr as expensive heads - from what ive read.

Good luck bamaboy and let us know what power it makes if u can.

Dyno Don

iTrader: (7)

Still think our dyno is dishonest?

Tibo

iTrader: (15)

What dyno is it? dynojet, dynapak, mustang?

confucius101

This is some info i got from ken @first awhile back

The flow rate of the FIRST Tpi will vary, depending on what is done to it. "As cast" it will average 234 cfm per runner all assembled, not just base or base runner combo like other companies like to print their flow numbers. With the plenum attached you can lose up to 11% of flow, that is why they test assembled. If you port, siamese etc. You can easily surpass 300 cfm, according to independent testing. As far as rpm range you can figure off idle to 5800- 6000 rpm "as cast" and substantially more with the aforementioned modifications. A lot this rpm range is really determined by engine and cam.

ASE doc

To the OP, I will say that unless you are going to the extent of exhaustive system engineering, it's best not to focus on a particular power level, rather on best performance from a given combination.

An excellent example of exhaustive engineering would be Allen, mentioned above in Dyno Don's post. His own work on his 1989 GTA is legendary. The time spent determining and achieving flow rates, runner lengths and engineering a very advanced exhaust system to compliment the engine allowed him to come very close to his power calculations.

Most of us don't have that kind of time, resources, or patience. I wish I did, but I have to admit I don't. Therefore, I take what I can from my own experience and what others have accomplished, and apply it to the best of my ability to make the best of what I have to work with. I do have the time, resources, and patience to do a good job of one thing at a time.

When I build another new engine a few years from now, I will certainly take the time to optimize the build. Then, I will install it using an intake that I have hand ported and prepared myself and my own self designed and built exhaust system. Can I honestly say that I will achieve any particular power goal? Certainly not. I can't even state for a fact what the flow rate or specific tuning point of my intake or exhaust will be. I have a power number in mind based on the results I've seen from other builds of the same type, but I am not prepared to take the steps needed to ensure meeting any particular goal.

I can predict with certainty that the car will be fast enough to scare the pee out of me, even when I work on factory hot rods most everyday for a living. I know that it will do very well against the flock of performance cars that it will meet at the local dragstrip. And that it will blow past almost any car on the road. It will certainly outrun the new SS Camaro and base Vette. That's good enough for me. It already kicked butt against the other street tire cars on its last trip to the dragstrip with the little 355TPI it runs now. That made me feel pretty good, even if I wasn't able to break into the 12s without sticky tires.

BTW, I would go with the 195cc heads. The velocity gained from the 180cc doesn't make up for the loss in cross section and flow potential. A good clue to how the heads really compare for flow and velocity is to look at the flow charts. Not just the peak number but from .300 up. The First, especially if you spend some time and clean up the runner castings(may require extrude honing), base runners and plenum, will flow enough to justify the larger ports.

The key to all of this is have fun, don't get too stuck on numbers, and be proud of what you build!

irocphilly

I hope thats its ok if I jump in here but I too need some help. I have a 1988 stock L98 IROC with cat back. I really want to order this FIRST TPI. I'm really hooked on it. I have an engine builder who has quoted me a price of about $7000.00 to rebuild my motor which has 116,000 miles but runs and starts. It does not seem as strong as my brothers stock 1987 L98. First 5 minutes of driving it feels strong but then seems to lose power. Do I need this expensive rebuild or are their better options. This is a street car and I would really like to keep my engine. First TPI is like mandatory. From Philly so if anyone knows of someone in this area who could help me out please let me know.

ASE doc

$7000 has to be alot more than a rebuilt engine. That must include R&I along with some upgrades. You can make 350hp with stock TPI components with some head work and a cam swap. TPI is one of the few factory systems ever made that is capable of a 100hp jump while using stock intake components. This of course requires porting of the stock TPI base, tuning the ECM, headers and exhaust upgrades, but it's still an easy 100hp compared to alot of other engine combos.

If you want more than that, you need to do more. I would start by looking at better cylinder heads. If you're going to go the expense and effort of a First Injections TPI, I would certainly make sure the base engine is capable of supporting the increased flow. This means good cylinder heads. The options there are many, AFR, Trickflow, Edelbrock, Dart, RHS, to name a few. That will allow you to make the most of your First TPI.

Sorry, don't know anyone in Philly.

irocphilly

ASE doc, thanks for the response. My particular engine feels as though it needs an update. My brother's car feels really strong and it has more mileage although mines appears to be in better shape. I'm hoping that someone can put together a combination with the First TPI for me. What heads, headers, cam............ I keep reading how well
everybody's third gen upgrades have worked out. Any help would be appreciated.

confucius101

I'm not really sure how well my combo is going to work out but

I'm running a first tpi with 355 with ported l98 heads dyno don headers ypipe into a 3" magnaflow catback

I'm at the moment looking swapping to some AFR 195 or 210 heads and either the tpis zz409 or zz9x cam along with a Holley engine /fuel control system

I'll keep you posted on my progress

ASE doc

Hi confucius. The 195 heads with 288cfm at .600 lift are all you will ever need, especially on a 355. Even if you upgrade later to a 383 or 400, the 288cfm supports over 500hp. The 195 comp package raises that 288cfm up to 308. That's a head capable of close to 600hp.

The larger 210cc port flows a slight bit more but at the cost of port velocity. Unless you're building an all out high rev motor for max top end and don't care so much about mid range torque, the 210, while they would work, will be less suitable for your build. The 195 is certainly better suited to the power band of the First TPI.

ASE doc

It's telling that your motor seems to run stronger cold. I wonder how your injectors are doing. Injectors tend to show their age more as they heat up. I also wonder if your ECT sensor is a little scewed and perhaps inaccurate at operating temp. Any performance upgrade needs to include modern injectors like the Bosch IIIs, in the correct flow rate for your new power level.

irocphilly

Ase doc what is an ECT sensor? I am currently buying the First TPI along with 1 3/4 dyno don headers. I have a Magnaflow exhaust. I have the opportunity to buy ported L98 113 heads with 24lbs fuel injectors used for $500.00 or lingenfelter 113 heads for $900.00 brand new. Which is the better buy. What else can add. I have a posi rear 277. Should I do a stall? What size cam? Roller rockers? Please help

ASE doc

Any good aftermarket head is a better buy than any factory head, regardless of porting. The only factory heads that are decent are the 113 vette heads, the vortec, and the LT1s. These all compare very poorly to any decent AM head made today. Take the $900 you would pay for the ported 113s and add $600, now you can buy AFR 195 street eliminators. They will out flow the ported 113s right out of the box and have alot more capacity for future power building. One thing to remember about power is too much is never enough. Once you have the taste for it, you will eventually want more. Best to start with hard parts that allow for growth.

Dyno Don is a great guy. I just ordered his dual cat collector pipes for my new exhaust project. His stuff is among the best there is. I wish I had his headers. I will likely get them when I do my new motor in a few years. For now, I will fit his pipes to my 1 3/4 SLPs and continue to dread plug changes.

Roller rockers are a given. Specify full roller fulcrum, forged units. Whether you choose the Pro Magnum stainless steel, or something like the Crane Gold Race narrow body, they reduce friction, help prevent valve float, reduce valve guide wear. The only reason you would ever put stamped rockers on a performance build if you were a crappy crate engine builder trying to shave cost. Ask me how I know that.

The 277 is numerically low(read as tall geared) for performance. Whatever you do with the motor, you will not see the results you should at the rear wheels, due to the tall gearing. Also, whether you have the 700R4, or the 5 speed, you have a great overdrive. So you don't need tall rear gears. I have the factory 3.23 rear gear. With the 700R4, the shifts are big and would be less big with a lower rear gear, like 3.73. But with a wide power band, I get by. At 65 in 4th gear, I'm doing about 2,300rpm. At 6,900 rpm in 4th, I would be doing something like 215mph. No need for a tall rear gear. Swap for something in the mid threes range. Anything from 3.23 to 3.73 would work well for you. The higher stall speed(I really like my 3,500 Egde converter) will help your motor get into its torque curve more quickly off the line, but it won't make up for the tall gearing. That you will want to change.

While you're shopping for rear gears, thing hard about a rear axle swap. If you ever get the itch to go drag racing and think you'd like to run sticky tires, the factory rear, whatever gear package you have, will not tolerate it for long. I see all kinds of upgrade efforts but I don't see anything that is going to make that tiny 7.5" center section strong. The 7 5/8" from the 4th gen isn't that much better. There is more than one AM rear housing and axle package available that allows us to bolt in either a 9" ford, an 8.8" ford, or a 12 bolt GM. I am going with the 9" ford from Quick Performance. It's a bargain for the peace of mind, knowing I can run stickies and not leave my rear axle in a puddle on the track.

What size cam is a personal choice. Whatever I suggest, you will either think it's too large, or you will think you want something bigger. The First has enough range to allow for some room here. The one thing I would strongly suggest is stay above 110lsa, 112 is better. The long runners want a higher lsa to prevent reversion. If you run the AFR heads, you can choose either a milder cam for better low speed manners(thinking of 223 @ 050, 510 gross lift), or you can go bigger for a wider flatter power band and that great big cam idle. I run the ZZX cam from TPIS cause I'm a little nuts. It's a single pattern grind with 240 @ 050 and 560 gross lift. I love this cam. BTW, I run Trick flow heads that flow about 270cfm.

ASE doc

BTW. ECT sensor is the ECM's "engine coolant temp" sensor. It is mounted in the front of the intake manifold, just below the T-stat housing. Black and yellow wires. To test it, you measure resistance cold and hot and compare it to the chart in the service manual. Basically, 3,400 ohms at 70 degrees, 180 ohms at 210 degrees.

irocphilly

Man you know everything. I bow my head. Maybe this evening you could give me a call so that I could discuss my build with you before I blow my money on the wrong parts. To us guys that's new to this, its very confusing. I need for someone to tell me what cam exactly to buy with what heads and rear. please. I'm locked in on a first tpi and dyno don headers. my car is stock with magnaflow exhaust. I just want to have some street fun and to never lose to a Fxxx Ford. My car is quick right know but not fast. 350 with 700r4 posi 277.