Phoenix'97

For a future build, I am looking into what type of camshaft would be the optimum choice for a daily driver. A camshaft that focuses on low end to mid-range torque production from idle on up to 5000 RPM, a camshaft with a smooth stock idle, a "sleeper" if you will, that can maintain stock emissions and fuel economy. After diving into some very mild camshaft upgrades, I am curious to get your opinions on which of the camshaft choices I am looking at will be a solid choice for the future build I have in mind. The motor I have is a second-generation LT1, but I would like to build it to behave like the L98 with the same focus on low end to mid-range torque production from idle on up to 5000 RPM.

The Camshafts I am looking at are:

1. TPIS Super L98
   220/220 @ .050" Duration
   .420/.420 Lift
   112 Lobe Seperation
2. Lloyd Elliot LT1 Custom
   212/222 @ .050" Duration
   .563/.562 Lift
   114 Lobe Seperation
3. GM ZZ4

As per the Smokin Vette forum: http://www.smokinvette.com/corvettef...cam-specs.html,
quoting Bad Karma,

1985-1986:
Duration @ 0.050 202/206 Lift with 1.5 R 403/415 Lobe Seperation 114.5

CAM 87 L98 14093643 Dur In/Exh 294'/294' Dur@.050" 202'/206' Lift (w/1.5) .403"/.415" LobSep 114.5'
CAM 88-89 L98 10066049 In/Exh Dur@.050" 207'/213' Lift (w/1.5) .415"/.430" LobSep 117'
CAM 90-91 L98 10111773 In/Exh Dur@.050" 202'/207' Lift (w/1.5) .413"/.428" LobSep 114.5'

92 LT1 205/207 @ 0.050" .451"/.450" Lift, LSA 117
93-95 LT1 202/207 @ 0.050" .450"/.460" Lift, LSA 116
96 LT1 200/207 @ 0.050" .447"/.459" LSA 117
96 LT4 203/210 @ 0.050" .475"/.479" LSA 115

With all of this information, I notice the GM ZZ4 has damn near the same specs as the LT4. So, pretty much I am clueless as to what camshaft or camshafts would be the ideal choice for the build I have in mind. So, here is where I ask for your wisdom and input to help me make an eventual educated choice. On a last note, the LT1 motor will likely utilize aftermarket heads with emphasis on port velocity performance over flow number alone, it will utilize long tube headers that can equip emissions devices and oxygen sensors and is optimized for low end torque, California catalytic converters must be used, and the exhaust system after the catalytic converters I would like to be a custom true dual Magnaflow set-up linked by an H-pipe.

Cjunkie

ZZ4 gets it lift specs from a 1.5 rocker, LT4 gets its lift from a 1.6.
Don’t be fooled the LT4 cam is really NO different than an LT1 except it gets a 1.6 rocker arm.
The ZZ4 cam is going to make a ton more power than all the stock cams.

vader86

Well you have the LT1 intake, which is not set up for low end and midrange torque, its an intake that comes into its own in the midrange and on up. Its not the camshaft or the heads that will change that.

Best thing you could do to improve that low end and midrange feeling is to add 4.10 gears if its a manual, or 3.54(or 3.73) in an automatic with a higher stall TC. Then it will feel more like an L98 off the line because you're getting into that power band more quickly.

So then my focus would be on a midrange & up cam, more like the LE Custom or LT4 Hotcam. Have the heads redone and install either of those, and I think you'll be happy, AFTER you do the gears.

cardo0

IMHO the cam is the last item to choose in a engine build. Gearing and headers w/exh system will limit what you need for a cam. If you have stock exhaust you will need a cam with much more duration than the intake to allow the cylinder to blow down. Gearing will emphasize the need for low end torque or allow less low torque for high RPM hp.

What I'm saying is if you are just considering a cam begin looking at the gearing and manifolding first.

Hope this can help.

Tom400CFI

Slap a stock L31 Vortec cam in there;

Vortec PN 10241264

Intake Duration @ .050: 191
Exhaust Duration @ .050: 196
Intake Lift (w/1.5): 414
Exhaust Lift (w/1.5): 442
Intake Lift (w/1.6): 428
Exhaust Lift (w/1.6): 457
Lobe Separation: 111


The thing will be a STUMP PULLIN" TOWAK MONSTAH!!!

Phoenix'97

Well, I really want to avoid gearing low to encourage higher RPM band driving. The way I drive, I prefer to keep my RPM low which is why I am interested in getting my LT1 to behave like an L98. This was what I was afraid of, the stock intake becomes a problem if I wish to use a cam meant for the L98. So, this helps to confirm the necessity to swap my LT1 intake manifold for one set-up for low end to mid-range torque. Thank you for your comment.


What you are saying does help. It makes me realize more what I need to do to my LT1 to get it to perform the way I wish. Thank you.


I will keep this one in mind as well.


Now the question becomes how to make a ZZ4 cam work well with an LT1.

ddahlgren

Does not seem like that big a deal. 112 LSA is still pretty tame.

GREGGPENN

Phoenix, this is actually the best recommendation of the choices posted so far.

To abandon SOME higher rpms -- in lieu of lower torque, you want to reduce duration. Keeping maximum lift will help too. (You want to get air in quickly...then seal off the chamber.

Lower LSA favors "front-loading" power.....just like a TPI. Something closer to 110 vs 117 is better for quick...low performance. You COULD use 1.6 rockers on a small cam -- but I doubt it will help since you don't care about power above 5k rpms.

Again, the choice posted above is a good one.

One "secret" that I'll tell you is TPI's "like" more duration on the intake side. It helps "catch" that 3rd reversion harmonic. And...like a restricted exhaust needs more duration, the TPI is a "restriction". It takes more time to move that long column of air.

The LT1 exhaust is FAR better than an L98 which means you can use the same OR LESS duration on the exhaust side. Listen closely....reducing exhaust duration can serve the same purpose as having less INTAKE duration. BUT...A TPI NEEDS MORE INTAKE DURATION.

You COULD consider a custom grind (from Bullet) which is what I'd do if I were building what you have in mind.

You should choose as lower OR LOWER duration than the L98 has....but you could pick more lift...or put 1.6 rockers ON THE INTAKE SIDE ONLY. Bullet has a few high lift cams in the 195-203 range. You could have them cut a single-pattern cam and leave the exhaust side with 1.5 rockers. Cut it with a lower LSA...and 4-deg advance built in.

IF YOUR BUILDER CAN DO IT, INSTALL THE CAM 4-DEG MORE ADVANCED THAN WHAT'S BUILT IN. IN FACT GO FOR ALL THE MECHANICAL ADVANCE YOU CAN GET W/O VALVE CONFLICT.

In reality, you could mechanically advance your stock cam, add 1.6 rockers on the intake and be pretty close.

Changes of 5-10 deg of duration isn't going to make/break what happens.

Here's the final caviat.... SINCE LONG TUBES LIKE MORE DURATION AND YOU NOTICE THE 89 CAME WITH 207 DEGREES OF IT, YOU'RE PROBABLY NUTS CHANGING THE CAM AT ALL.

Bonus note....Bullet cams has a tab for "Tractor Pulling". I'm serious. It says "We can regrind your stock cam for MORE TORQUE". Check it out.

Like I said in your other threads, you need to study up more. Simple basics of cam theory will point you in the right direction. The point I made about long tubes is about the only "secret" you'll find here. And, the irony of it IS...it's impossible to decide if you want less duration for super-low response OR more duration to maximize that mid-range reversion "hit". Or...if you can get both with a combination of lower duration, lower LSA, and high lift.

Guess who'd be the best expert on that? Us? Or a company specializing in cam grinding? Guess what I think the odds you'd actually CALL them are? ZERO. That's because you'd rather WASTE time talking about something you've tentatively got planned for your RETIREMENT.

LOL

So there you have it...the good, the bad, and the ugly.

GREGGPENN

What helps to confirm "the necessity"? You've GOT to be kidding! This entire paragraph CLEARLY demonstrates how confused you are and why you end up laughed out of forums.

If you WANT more torque AND you use gearing to get it BUT you won't be able to resist high-rpm driving, YOU don't have the desire/control to drive like you THINK you want to! Gearing provides what you WANT but you won't choose it because you can't control yourself. PLUS, you've made ABSURD comments about mechanical limitations that will PREVENT you from driving above certain RPMs.

You expect us to take you seriously? Really? If you were SMART enough to see what you say, you'd get it...

If you REALLY want the most low-end torque but be able to pull it WITHOUT high rpms, you need more CUBIC INCHES. A 454 will PULL in lower gears, now won't it?

If you want to create that same level of torque WITHOUT actual engine power, GEARING is the only other solution. PERIOD...the END...FINITO...ARRIVA-DERCHI...SMELL THE ROSES...DUDE.

What MAKES it to the wheels is a combination of engine torque (at any given RPM), differential gearing, and transmission gear selection.

Do you want 3rd to pull like 2nd? Or 2nd to pull like 1st? But not have a bigger engine? GEARS....GEARS....GEARS....

Why can't you understand that? REALLY.....WHY NOT?



BTW...I'll give you 3 guesses why there's little-to-no research on the best combination for a TPI low-torque, high-output, longtube setup? You know...the kind that would show YOU whether YOU want more of the lowest RPM response OR maybe better midrange.

That's because people abandon the TPI when shooting for more power. Builders didn't spend any time on it. Lingenfelter spent the most and he determined SHORTER tube lengths more similar to our modern LSx engines were better.

Is shorter better because it IMPROVES off-idle performance? Is shorter better because you can get a good mid-range bump with more duration and less LSA AND....

Use less duration for off-idle torque?

Do you think anyone here will KNOW the answer to that? Do you? Do you think it will affect what you'll do in 3 years...or when you retire?

I think you should spend hours and hours on the phone with cam grinders until THEY point you in the right direction. After all, THEY are the ones who will eventually get your money.

Or....

Will they?


Sorry, I gotta go before you drive me batchit-crazy again.

Churchkey

IMHO its not worth a cam change to achieve your goal.
Simple solution = change the gear.

or

Advance the current cam 2*, 1.6 rockers, 1 5/8 long tubes, dial it in with a gear change.

or

leave it as is & add a blower.

Phoenix'97

Short and sweet, will this comment of yours work with my stock LT1 intake meaning I don't have to jump through hoops to TRY to get a TPI intake to work on my LT1? If I can gain the same performance of an L98 from a camshaft and necessary modifications while using my stock LT1 intake, then I will drop the notion of trying to use a TPI intake.

You get more from comments coated in sincerity than you do with comments coated in insults.

GREGGPENN

OK....In ALL sincerity, I answered your question halfway through the post you just quoted. If you REALLY want to use a TPI intake, put 1.6 rockers on the intake side of the cam and call it good. Advance the cam as much as you can w/o conflict in the valve train. That's not really for the TPI so much as to MAXIMIZE the crawler RPMs you want most responsive. And, since you don't care about top-end performance.

Personally, I still think you'd be better off with a 396 with a small performance cam installed/ground with maximum advance. Your mileage wouldn't take a hit, it would be as responsive as possible and you'd have more fun than with a TPI.

In ALL sincerity, that's what I would do...if I was starting with an LT1 right now. Of course, I'd also port the heads or buy AFRs with a big enough budget.

In ALL sincerity, how many people have giving you feedback about gears, or cam, or forced injection, or more cubes vs converting "back" to a TPI?

In ALL sincerity, how relevant is ANY of this 3 years out from any consideration of a serious build? Find some cars to drive to get a better feel for what happens with each "build". Try LS cars. Try TPI cars. Get personal experience, read about options, THEN ask your questions.

Tom400CFI

....Totally. OP, listen to Greggpenn

...and he'll probably never do it!

383vett

My goodness, you just trolled through this forum a couple of weeks ago with your ridiculous intake questions. , Now it’s the camshaft. Did you already abuse the fbody forums with this stuff? Why not just trade for a truck? As I recall one important requirement is that you can drive in snow at a low rpm. A pickup should suffice. Then you can bust your chops at the truck forums.

Tom400CFI

Right?

For the price of making that intake "work", he could buy an old beater 4wd truck and run the wee out of it in the snow...save the car for fun days.

Phoenix'97

Well, a pick-up is too lazy an option for me, so too is a beater ricer. The real test is surviving winter driving something like my LT1 fourth gen Trans Am; it is fun, it can be very difficult, but I wouldn't want to drive any other car knowing what my rear-wheel-drive is capable of in the heart of winter when I get the momentum going. For me, my thrills come from experiencing the *** end swing out on a snowy road and only needing to let off the gas pedal to get her straight again.

Now, I am seeking knowledge on what to do with my motor. I had a game plan with using an L98 intake to make use of L98 camshafts on an LT1, which can be done. It is easier, yes, to use my stock intake but try to find a way to replicate L98 behavior out of an LT1, which the camshaft seems to be a major area to do it.

Now I received advice on that L31 camshaft and basically they told me to avoid it like the plague as it too goes "backwards" in performance and won't really satisfy what I am trying to achieve out of my LT1.

So again, opinions can be good and they can be very bad, especially when it's all a joke to some.

Tom400CFI

Who told you that? When? Where?

bjankuski

I do not really understand the problem, the LT1 makes almost the same amount of torque as a L98 330 ft/lbs compared to 340 ft/lbs. It is a flat torque curve compared to the peakier torque curve of the L98 so the L98 appears to hit harder when in reality it does not. Just change the torque converter to be around a 2000 stall or change the gears to something slightly more aggressive. You will have just as much low end power as a L98 and it will not be rev happy on the highway. You can still shift at just as you do now.

Phoenix'97

Other forum, I won't be specific. I told you I am doing research and collecting all avenues on which to proceed. You have hella crazy with trying to get a TPI intake on my LT1 and to clear the metal cowl in the engine bay, and to brave using an L98 camshaft on an LT1 using a TPI intake. I do understand there are problems galore to be had. There was a guy running a ZZ4 cam on his LT1 without a tpi intake but that was for his chevy pick-up truck and he was running lower gears than my stock ones.

The other option, with more predictability, is to keep my intake but have a custom grind made to give me my at idle instant torque and to push that torque as far as we can go with the cam. Like I said, I want my LT1 to behave like the L98 and I want that instant torque at idle on up, to pull hard on up to where it peaks. I thought the L31 camshaft might be a good idea but I have other LT guys saying no, and that a Lloyd Elliot camshaft will be far superior to the L31.

Tom400CFI

Sounds good. You've got a good plan.