I will say one thing good about the TPI motors...when compared to the LS1 that is. They are darn good looking intakes. In my opinion, probably the sexiest looking intake. Especially when polished, or when accented with some tasteful paint. No other cars had motors like that... Just the Bird, Camaro, and Vette... Which is pretty cool if you ask me.

The LS1, unless you relocate the coils, get new valve covers, and are really good at hiding wiring...is for the most part ugly as sin. Coil/Fuel rail covers help...but unless you want to customize them, they say corvette. I dont want to turn my car into a corvette, so Im staying away from them at the moment. However...take said LS1, and put a nice set of painted fuel rail covers on it, a few polished items here and there, and it looks hot.

Justin

 

Yea, TPI are the best looking intakes ever. And LS1s....are pretty ugly.
I think am going to have a customset of fuel rail covers made. White, with black lettering. CAMARO in the 3rd gen style. Sanded and clear coated to be smooth. Might see if I can have the intake painted white to match. I don't see why you couldn't. I mean, they're plastic.

 

To choose between keeping TPI and swapping LS1, I dont know because I like LT1. It depends on if you want to do the swap and what your goals are.

As an LT1 swapper, I admire the locations of the accessories on the F-body Ls1. A/C and Alt mounted low with PS on the drivers side, I would love that, well if I had a tubular K-member. Just really cleans up the bay by hiding everything down low. I like coil packs too but they can be put on an LT1.

Another thing to think about is the tranny if you go automatic. I really do not like TV cables and 700R4's. 4L60E's are nice. They can be made to work with Gen I SBC's but you have to buy an aftermarket controller/computer for them.

 

i didn't have time to read through everyone's responses but i've been there so i'll add my opinion.

NO. it definately depends on what you do with the L98 but to do it "right" it's right around the same price to make your L98 equally nice. in my case i wanted to blow the doors of ls1's and it was twice the price. what did that mean? well the motor ran hard but i was stopping at the pump alot. not to mention it's older technology.

for the price you can't beat it. i will never bother building a gen I sbc again as it's not worth it in anyway.

 

I've looked at this Gen I vs. Gen III issue almost constantly for the past few years as I try to find the time and money for "The Build". I've read test after test after article after article and I'm sorry there's absolutely no comparison. I'm a die hard TPI guy, but you just can't have your cake and eat it too with the TPI. I know I know, someone will always have a TPI getting 30+ mpg and making 500+ naturally aspirated, sure, OK, whatever, but for EVERYONE else, it's impossible. Post receipts, dyno charts and timeslips and then we'll talk, in the meantime, the rest of us all know it's impossible.

...as for cost, everyone has different goals, different budgets, and different hook-ups. If ya wanna be in this hobby, and ya wanna go fast, then you really can't be stingy with price. All in all, any motor is gonna cost money.

And to put the argument to bed, if the LSx motor wasn't an all around better motor, then GM would be running all TPI motors. They're not, and the LSx is better.... .....as much as I hate to say it.

You don't see many 4th genners swapping in L98s do you???

*EDIT*
Now don't get me wrong, there are still a hundred reasons to stay with the good old TPI. I'm still debating it myself. "Which motor is better", is not the same as "What should I do". ....and for that matter, if the L98 works for YOU, then it IS the better motor!

 

Wow. Great way to sum it all up, Kuddos!!

 

MSD makes a coil-pack setup for an LT1 that replaces the optispark. And its not cheap.

Of course not. A) its against emissions laws to put in an older engine, B) the TPI intake will not fit under the engine cowl, C) There's no question the LT1 and LS1 are better stock engines in 4th gens. The issue is whether an L98 can be built up like an LT1 or LS1 for cheaper and easier in a thirdgen, and I say they can.

 

I think turbo TPI cars are the set up to beat for the $$ with what TurboedTPI's car has done with how little is on it is amazing all told he may have slightly more than the average cost of an LS1 swap and runs 10s with a very streetable car (He drives it everywhere) It makes me very very pissed off that I missed out on BBS turbo headers every time I see his car

GO TIMMY!!!!!!

 

I agree TurboedTPI's car is pretty kick *** for what he has in it(my hero), I'am hoping I can get somewhere close to his times and still keep it TPI and cheap but if I didn't already have a blower I would go LSX. I don't know about you guys but I'am tired of looking for the gas station every time I go out LOL. How does the LSX compare to the L98 for city driving?

 

my car has a decent size cam, runs low 7s (well into the 11s if it was 1/4) and gets 19mpg city, 28mpg hwy, with me beating the **** out of it everyday to and from work.

 

Bout the same as Mr. Dude... My car will run low 11's on 93. Cruise around just fine. And if I get to use 6th gear, my wallet stays alittle fatter.

Not sure about beating the **** out of it tho... If I did that, I wouldnt get as good gas mileage. If I drive like a normal person...its great. If I dont stay out of the skinny pedal, then it drops a bit. But...what car doesnt? I will say, it doesnt take much to sling shot that car up to speed tho Sometimes it doesnt even feel like the motor is doing much work, but the car is hauling.

Justin

 

well, by beating the **** out of it:

i leave a light fast.... but at the top of 1st, i usually shift to 6th...

on the highway, i usually cruise between 70 and 80.

im not shy about dropping it down a few gears and revving the **** out of her, and making a quick dash into triple digits if traffic suddenly disappears on the highway...



if im really nice to her, she'll give me 20 or 21 mpg... but im willing to drop down to 19 to have some fun. it is kinda funny how if we have a week of rain/foul weather, my MPG goes up..... because im not flooring it and fuging around...

 

thats what the car was made for! enjoy its power! no shame there. but that mileage is very impressive. i would think a 400+whp LS1 would consume more gas than that when ur driving it hard. highway 6th gear crusing i can see 20-25mpg, but city/daily stuff on the pedal i would expect 16-17

thats one thing about the ls1's...they all talk about the powers they make with simple mods and what cam produces what power. they talk about head flow and all that fine stuff, and every now and then you hear about the great mileage they get, but i just never see the numbers.

 

Thats because its easy to get a dyno graph to show numbers.... or flow graphs to look at the heads... etc. But its harder to prove MPG. I can get a reciept at the gas pump, show you the amount I put in, and how many miles are on my trip... But again, you'd be taking my word for it that the trip was reset at fill up..etc etc.

I never thought Ide get the MPG I get out of a 400+ hp 11:1 compression ratio motor either. But...it works. Like Mr. Dude....I dont exactly drive my car like Miss Daisy. I take it easy but I definetly dont shy away from seeing 6500 rmps and triple digits. Its so easy to do... My old TPI motor I needed a good stretch of road to really crank up the speed. This thing does it in a snap.

Justin

 

i try to track my MPG as accurately as i can... i always fill up the same way, with the nozzle at the same angle, at the same pump...

i used to type all my receipts in a spreadsheet to keep track, but i dont always remember to do it anymore...

to be honest, the last 3 months, the car hasnt been my daily driver.... the clutch started slipping, i was moving into a new house, ect....
and now that i have my house and im settled into it, the car is currently on jackstands as i redo my exhaust, and upgrade the clutch.

 

...

 

OK, let's throw out ALL the variables. Here's the situation:

You have a fully ready to run Thirdgen F-Body, but no motor. Some nice stranger donates a BONE stock LS1, or a BONE stock L98, and you just happen to be a GM electrical engineer, so wiring and tuning isn't an issue. Due to a new federal ban on our freedoms, ALL car shows have been cancelled, and you're not allowed to EVER lift your hood, unless it's to work on your motor. THE ONLY THING to decide upon is performance and driveability. From here on out, any mods you make come out of your pocket, but you can do what you want.

What motor do you choose?

I've been here WAY too long to even THINK half of you won't say an L98, I just want to see what your reasoning is. It promises to be entertaining.

 

Same as it was before I read that. LS1. And who needs car shows when you have the internet?

 

...and for the record, (not counting the above situation) I still lean towards the L98. I love the nostalgia, the look, the braggin' rights for having a bad azz looking intake. I will probably end up building my L98 for those reasons.

....but I you just can't talk apples to apples and STILL choose the L98. It's old technology. If you take power, driveablity, economy, and reliability all into consideration, the LSx is the way to go.

 

My gas mileage isnt that great around town anymore. Probably 20mpg if I'm lucky. On the highway I still get 25-26 (3.73's hurt it some). Lately, I have been driving 170 miles to and from work, once or twice a week. Other than the highway driving, I very rarely "take it easy". Around town, the bottle is always warm and turned on.

IMHO it just makes more since to start with the LSX motor and go from there, rather than modding the L98 to just catch up. Thats just me though.

 

Yup, same here. You can do heads, cam, mod the plenums, get a bigger TB, aftermarket runners, headers, exhaust and make in the 300-350 rwhp range. Or, swap in a stock LS1, and make 300-330 rwhp range. Then do the heads, cam, LS6 or FAST intake, larger TB, LTs, exhaust and you'd make 400-500 at the wheels, depending on the heads/cam you use.

 

Your scenerio from above is an easy one for me atleast. LS1 for sure. And on the other hand....Im nostalgic as well. Otherwise I wouldnt be driving around an older car in the first place I guess. IF....IF... I had a very very nice thirdgen. Im talking showroom condition or better. Never wrecked, never wet from rain, zero rust... Then Ide keep the TPI. It would also probably have to be something special...Like a GTA or an IROC or something.

However..my car was hurting driveline wise, its got some paint issues, it has alittle rust here and there.... Nothing special about it. So....why not make the sucker run like a bat out of hell and be completely happy with it.

J.

 

okay, I have a question.
I was looking at a post on the DIY PROM board about an OBD II for the TPI.
is this probable at all and even practical cost wise.

If i could do this I probably would, or if I could just stick a TPI on a Gen III block then I would. Maybe i am just dreaming, , i dont know.

and most TPI's are faster than LS1 in the 0-60 mph range, right?
and the LS1 are faster from the 60-150 mph range, right?

if this is true (no taking into account really worked over engines, maybe suspension though) i like to go faster frm a stand still so i would go with the TPI. even though the LS1 in the end after its potential is maximized would kill the TPI in ever aspect except for appearance.

 

The TPI would choke the crap out of a Gen III even if you could get it mount up. And while the TPI are more of a bottom end engine and the LS1s are stronger top end, that doesn't mean the TPIs are faster 0-60. As far as I know, LS1s are stronger throughout the range.

 

well naturally thats not a real fair comparison. it be dumb to not choose the stronger factory motor. but what about a 350hp ls1 or 350hp TPI? then it be a hard call. the TPI motor would make more low end power and could potentially by faster by gettin off better 60 foots.

my L98 has an estimated 230-240whp and probly in the 300-330wtq. I cut a 1.74 60 foot so far, went 13.63 at 97
my friends LS1 goes high 11's/low 12's at 113-114 and made 365 without tune and near 340-350 wtq. he's only been able to get a 1.77 60. granted his is a stick car and mine a stalled auto, but he has a ton more gear than me and power, so his launching ratio is higher than mine. several other LS1's doin 11-12's are only doing high 1.6's to low 1.7's.

thats one reason i like TPI. it launches hard for the low power it makes

 

Do you mean crank, or rwhp? LS1s make about 350 at the crank stock, so it's pretty much the same question.

Good 60 foots, BTW. I wish I could get into the 1.xxs lol

 

why exactly would a TPI choke the crap out of a Gen III then a Gen I with Aftermarket heads?

and how about the OBD II on a Gen I? would the TPI be more effiecent then and also pick more HP and TQ, or just be a lost cuase thats just a little ealier to be tuned than a OBD I.

And besides the aluminum block, spark in head, better engineered heads, and OBD II what are the differences between Gen I and Gen III?

and one last questionwhat size/differnces are the LS9, the LS3? what exactly is the L92?

and as I understand low end power and "grunt" is the advantage of a LTR setup.

 

Because, stock TPI doesn't flow very well above 5500. LS1s rev to 6100 stock, and even higher with mods. I don't think that the TPI flows the same CFM as the LS_. Although, if you could get the TPI flow well past 6000, the longer runners would make for more low end grunt, but less top end.

I don't know about the OBD II.

The LS3/LS9 are both (supposed) to be 6.2L engines with awesome heads (same as L92, I think) and intake, but the LS9 will be supercharged. LS3=450 and LS9= 600.
The L92 (also 6.2l) is the truck version of the LS3. More low end torque at the price of top end power. But, that's mostly due to lower compression and the way the intake flows.

 

so let say you got a TPI base, SLP runners and ported the fudge out those and the plenum, then with a 58mm TB ( not saying it'll make a ton of difference) and put that on a GEN III block it should have plenty of low end, right?

and will LS1 injectors fit on a TPI base, and if so could you then use TPI fuel rails or make your own, install need sensors and hook up a painless OBD II harness, and BAAM, you got your TPI with your new Technology, your low end grunt and great luanching power (my personal favorite) with better gas mileage and easlier tuneable technology and of course nostalgia.

and being that i want to drive on the street my car needs to be smog legal, since the LS3 and LS9 are truck engines, does that mean that you couldn't legally put them in your car and get it smogged? or are you just talking bout using the heads/intake/blower on any other LSX engine?

 

I don't know the flow numbers from LS1 vs TPI, so I don't know if the numbers would be the same.
I don't know about LS1 injectors fitting, but you could just get bigger aftermarket ones.
The fuel mileage doesn't only come from the heads, it's from the intake and everything.
I don't really see the point in doing this kind of modification. With the money you put into all that, you could have modded the LS1 and made up the difference in torque and make more horsepower. At least I think you could. Plus, I'm not sure that a TPI setup can be mated to a LS_ block.

 

Uh... Im pretty sure there is NO way you could ever put TPI on top of the LS1 block. Unless you could cast a custom TPI base. The LS1 heads have long tall intake ports. The TPI uses regular SBC ports. Its just a totally different beast all together.

On the 350hp LS1 vs 350hp TPI topic... Assuming we are talking flywheel HP...which puts the LS1 at stock pretty much, you will only be modifying the TPI. Which takes us back to the reliability and economy thing. The LS1 will still be a stock block that is very reliable, and still get good MPG. Now, Im not saying the 350hp TPI motor wont be reliable or economic...but I still think the LS1 has the upper hand.

Man someone with some money to burn should build a TPI to match the output of the LS1...and we can do some testing Man I love both motors. haha.

Justin

 

yes i didn't expect a TPI base to go on a ls block and heads, but dont see the problem with sticking LS injectors onto a TPI base, and with a harnes/ECM/sensors, you woud have a an OBD II TPI. and I dont think the intake makes up the will ditate any MPG at all, but the effiecency and controlability of the ECM is what decides the MPG of the car (engine wise, not considering gearing and the tranny)

anyways thats what i would do, make a OBD II TPI on and Gen I block, it would still be easy to work on and bolts into the car pretty easily, just dont know if that even smog able since its technicaly two different engines.

 

No, it's not fair, that's my entire point. It's like asking who's the better football team, an NFL team or a pop warner team. Naturally the NFL team, and naturally the LSx motor. That's the point of the whole conversation. Now in the "real" world, things like money, nostalgia, friends who can pass you with no smog equipment, those things DO matter, but apples to apples, all things being equal, stock to stock, it's not fair, and it never was. The LSx is the choice hands down.
-----------------
As far as the TPI on a LSx block and heads, no, as stated, you can't do it. Gen one ports are EI IEEI IE, GenIII are IE IE IE IE. Maybe that's backwards, but you get the point.
-----------------
The TPI does make more torque down low, but that doesn't necessarily mean it'll get off the line faster. I'd consider myself an "average" driver on the track, and with my mild mods, my TPI overpowers my traction/suspension. In my case, it actually slows me down. I'm actually saving/buying rear suspension over the winter to solve this I wouldn't consider this a weakness of the TPI, but rather a weakness of suspension, but again, there we go comparing apples to oranges.

 

Well, you sorta can. I think the actual GM/LSx computer times the ignition off a crank position sensor, which our blocks don't have a provision for, and our "batch fire" computer/injectors don't allow individual cylinder tuning like the LSx computer. That's why the new blocks and old computer/old block and new computer thing won't work. However, all the aftermarket EFI software is tunable to the 'nth degree. They DO work with Gen 1 hardware/blocks/ignition, and they DO allow the Gen3 like tuneability. They're pretty darn expensive though.

 

when your comparing performance numbers its not fair to compare a modern day 350hp stock motor to a 17 year old 250hp motor. you have to compare motors that make the same power to really see what each design offers. TPI can reliably make 350 crank hp and get good mileage. 350hp isnt alot. but TPI will give you more power under the curve in all rpms 4500 and under. thats a nice boost of power. fuel mileage might be less tho, but not a whole lot different.

in the same car assuming same weight, that TPI motor will be faster. alot more usable power.

it all comes down to pricing to build the motor and to fuel it...comparing Gen I to puttin in the ls1

assuming you build the TPI motor fresh, aka 0 miles, you'd have to swap in a brand new LS1 crate, in order to compare two fresh motors for best reliability. cuz a 2500 dollar 60K mile LS1 wont have the same reliabilty as a 0 mile properly built small block. just the wear and tear factor.
the LS1 crate for 5 grand..then you'd need the swap parts and a trans to work. prices add up really quick.

GEN I for moderate power levels ( under 400-425 crank hp) seems to be the best bet, new motor to new motor. its cheaper. you build up a 6 grand (probly abit less tho) 350-383, that makes an honest 400hp crank, and compare that to the cost of a new LS1 with bolt ons that will make 400hp, its FAR cheaper to stay gen I for moderate power numbers.

the fuel mileage of the two motors will be different maybe...more in favor of the ls1...well thats great and all, but the amount of money you save in doing gen I compared to LS1 swap, you can buy the extra gas you need, not to mention other parts for your car.

and it money you'd need for fuel wont be much, cuz the majority of these cars with good bit of power are toys, and probly dont see more than 7K miles a year. unless your a southern boy lol that can enjoy that weather. even then it might be only driven not that many miles a year

if it is driven alot, its probly more highway than anything..which 400hp is capable of gettin decent mileage...esp if T56 trans, but even with 700r4 with ok gears, its not bad. probly near 20mpg if tuned ok, and i'd bet it be possible to get more out of it.

for big numbers, 450-500+hp n/a...you cant go wrong with LS1. thats where they shine. sure for similar price new motor to new motor, you can build a 383 to make 500hp and maybe for cheaper, but that 346 LS1 will do it and probly see better mileage and better streetability which pays off in the end.

and the fact is most swap in used motors that are goin for fairly cheap. 2500 bucks can get u a decent LS1 to start with. say 3500-4000 for the motor/trans combo. ppl will look at the cost to build that into 500hp, vs a Gen I which they'd have to start from scratch (cuz most 350 L98 cars have high mileage now and couldnt hold 500hp on stock internals anyway) or buy someone's built short/long block which is hard to find one that fits your goals/specs. so most times they do build new. now the prices look to be infavor of the LS1 combo for that big power output.

 

I know LSX makes great power and stuff but how would it compare to say a L98 with AFR heads with same cam and compression and with simular size runners for intake, how much are we really losing between the too? I'am talking power and gas milage.

 

that would be stupid.
the TPI would choke the crap out of it...
the LS1 DOES HAVE A LONG RUNNER INTAKE..... its just a modern one that doesnt stickup with stupid tubes.... think of a candy cane... long straight from the runner, then currving down and back...
then think of the top of the LS1.... the runner goes from one side across to the other, turns down, and back to the plenum..


no and yes.

the LS1 makes more power EVERYWHERE.
pick any point on a dynosheet and the LS1 makes more torque and more horsepower there.


i like the LS1s looks. maybe its just because im a gearhead and not a showcar guy, but an all alum block, alum heads.. powerful coilpack ignition, and a cool temp, well flowing nylon66 intake just looks damn good..
but then agian, im not into showcars.. im used to looking at race cars... so the pretty doesnt factor in as much as the wow of what this part or that part is capable of...


exactly. they make more power everywhere, including lowend torque.
L98s do FEEL faster.
LS1s pull so smoothly and evenly when stock that you dont notice how much faster they are.. thats why the powerband is often refered to as "sneeky fast"

they're also thought of as topend motors because around 3500 (where you tpi chokes and dies BTW) they start pulling alot harder..... but that doesnt mean they wernt pulling hard to being with.



well... the TPI flows like crap and chokes the stock TPI motors.

it would really choke the crap out of the LS1 because the LS1 flows so much more air then the TPI is capable of.

it would really choke the crap out of the genI with aftermarket heads because the the head wants to flow so much more air then the TPI is capable of delivering....



the root of TPIs problem is the intake. not the electronics.
you have a tiny throttlebody feeding a crappy plenum... after the air makes a sharp, non bellmouthed right angle turn in that plenum to the runner, it has to go down a poorly designed undersized tube.... then into a base that flows like doggy doo.

keep everything and swap to a LT1, stealthram, T-ram, or other performance SBC EFI intake, and you'll pickup power.



everything.
-----heh, i started to reply, but it was getting to long...
theres more then you can imagine.. its a diffrent motor. peroid.


thats like asking whats the diff between a L98, L03 and other SBC engine codes...
L92 is the first of the new wideport head motors... they make LS1 heads look like they flow doggy doo, and make SBC race heads a joke... all for $600 a pair.

then understand this... the LS1 has a LTR setup.




no, you wold lose power. and lose torque. that "lowend"? would be DOWN.




FYI, injectors are irrlevent..... and the rest of what you said is crap too...



you're so off base, im not even going to attempt to correct you....

no it doesnt make more down low.
but yes... more "down low" doesnt mean it'll get off the line faster anyway.. only a total idiot/newb would launch a dragrace from idle.. lol.


and that TPI hooking problem is common.. because the power isnt there... then it "hits" with some decent torque... then it chokes itself..... so it FEELS like a big lowend grunt hit..but really... its only useful for spinning tires and leaving the stoplight swiftly.... not for drag racing where the launch starts above three grand...

 

the LS1 would stomp it.

the stock, unported 18* LS1 heads outflow the CNC ported AFR heads.
the $650 CNC ported stock LS1 heads outflow anything the AFR heads are ever capable of..... by alot.

so from a power standpoint..... with the same stock cam (unlikely) the LS1 would have alot more power...

lets say you can mildly cam the L98... from a flywheel hp rating.. it'll now have 350ish (just saying.. mild cam, AFRs...) thats the same as a stock LS1....
cam the L98 more? then just cam the LS1 a little more, and it'll always be ahead.

from a MPG standpoint, the LS1 wins.


btw, im assuming you mean L98 with the TPI ditched for a diffrent intake.. if you want to keep the TPI intake, you'll have trouble reaching that stock LS1 level of 350flywheel.... nevermind the higher numbers.

 

I'm just wondering, but what CFM do the AFRs flow int and exh and at what lift?

Stock LS1 heads flow: 227/180
Patriot CNC 5.3L.......: 296/220 (stage II, stage III = 302/230)
stock GM L92...........: 328/223 ($800/pair, assembled)

 

most all 190-200cc aftermarket aluminum heads for small blcoks flow 250cfm or more. AFR advertises 260-270 or so. Patriot 23degree heads advertise 260's as well.

stock LS1 heads i thought flowed 250 or near that.

in chevy high performance, they did a test on a 406 gen I vs a 402 LS1. i dont happen to have that issue for some reason..i cant find it but i'll look harder. i do know that the ls1 made 583hp..Crank hp thats very stout. but a 406 with good heads and intake should have no problem matchin that. 87TA's 406 is probly around that if not higher..and still streetable. but it does have a solid roller. i'm not sure about the ls1

 

Mr. Dude: What was meant by the TPI making power down low was that it makes more of it's power down low compared to the LSx. I was thinking torque curve, not peak. ...and as we both pointed out, that doesn't necessarily mean it's gonna be quick.

And as much as I'm enjoying this discussion, it's difficult to really discuss all the different variable that effect any given situation and be sure we all understand exactly what we all mean!!!

....When I think L98, unless specified, I think long tube TPI. (That's just me). Now before someone jumps on ya for that quote, I have to say, I haven't seen many long tube L98s making 350 rwhp, and to those that have, post up a quick list of what it took to do it. hehe, I'd be interested!

 

re-read what i said.

take a LS1 dyno graph and a L98 dyno graph with the scale being the same between the two.


pick ANY point.. from idle, to 1500 to 2000 to 3000 to 5252...... and the LS1 is making more torque.



im not comparing peak either. the entire area under the curve is larger.

 

Nope, I'm with ya.

....what I am saying is that regardless of the numbers, the LSx motor has a flatter curve. That's a good thing, it's more of a well rounded curve. The TPI's strength is down low and then it's weakness is up high. I realize that the LSx motor's torque, regardless of RPM, is still a higher number.

I just re-read my original post on the "low-end TPI" and I guess it does look like I implied it actually had MORE torque than the LSx. Not what I meant.

 

thats not correct. heres a stock LS1 dyno chart and it never made more than 300lbft... and that seems low for an Ls1..most in the 310-320wtq range. but L98s are above that. i made 261 at 4000rpms!! thats way above peak rpm for an L98. i expected my car to do atleast 330wtq but its impossible to get a good read on the dyno with the converter and the trans kickin down at 3K rpms in drive


the LS1 torque curve being flat is better, but an L98 can make bigger numbers down low..below 3500rpms, in that window between 2800-3400rpms, and its fairly close below 2800

 

Well, even if a TPI makes more down low (and I'm not saying that they can) it does die around 3500, at that point, the LS1 car gets into it's go zone as the TPi is starting to loose it's gusto. And that's an extremely modded TPI to make power to match that of the LS1.

 

Your kind of missing my point here, just saying it will stomp and LS1 win's on MPG is not what I'am after.

There is also a couple of things I think your saying might be wrong.

First I'am just looking at this one mag in front of me here it's talking about the LS2. The stock flow for these heads are 254/189, I don't remember the LS1 heads flowing any better. The new 195 eliminator AFR heads flow 286/215 but I must admit after the LS2 heads were CNC'd they were flowing up to 305/237. Can't say how big the runners are at this point though but there next stage up CNC job there runner size was 220cc flowing 310/237.

Second your still thinking I'am talking about stock style runner TPI engine, I'am saying if you have a custom intake that has the same runner length so that 350HP you talking about for a mild cam engine seems really low.

Just to give people a example of what a LS2 can do stock and with mod's I'll go over what was in this mag artical.

Stock power for the 364 ci LS2 was 402hp/437ib-ft, with mild stage 1 cam 218/220 .570 lift(114 separation) power went up to 494/450. After they installed there stage 2 cam 234/236 .600 lift(114separation) and power was up to 500/449, out of head at this point. Next they installed there stage one CNC ported head and outcome of that was 520/467, not sure if they went back to the stage 1 cam on this pull but I'am guessing not.

Orr89RocZ, I also remember reading a little about that test between the 2 engines at the store, basically there wasn't really a HP difference but I do believe the 406 might have had a hotter cam and driveablity would be alittle ruffer. Thats basically why I was asking the question if a SBC1 could even come close to the LSX with todays head's, compression, same size cam and runner length intake, plus MPG to boot

 

The LS2 isn't a Z06 motor. The LS2s are 6.0L and generate 400-hp (stock crank rating) and are the base model engines for the C6 Corvettes.
And what Z06 heads are you talking about? C5s (LS6) or C6s (LS7), because the C6 Z06 heads flow more than 330 intake stock.
Stock LS6 heads (from http://www.smokemup.com/tech/ls1.php) flow 257/183.
According to LS1Tech, the stock LS7s flow 360 @ .700. But that seams a little low for the LS6 heads. I thouht that they would be be much closer to 300.

 

LS2 heads are just the LS6 heads with different valve train components.

todays 23 degree heads have come along way since the late 90's when the ls1's were coming out. power numbers can be closely matched, but i havent seen tests comparing mod for mod ls1 vs 350 small block or anything for that matter. only one was the 406 vs 402lsx test and i havent read it

 

My bad got the heads and cam mixed up, I'll just correct that lol!

 

It's cool, I was second guessing myself. I was thinking, "Well, I thought I figured the designations and the cars out...."
I know one thing for sure, I would love for someone to drop a free LS7 in my lap. The article I got those numbers from show right around 400cfm when ported....*droool*