My ported cast L98 heads flow 248 intake@.480lift and 181 exhaust @.500".
Stock LT1s flow 210

 

L98 means an aluminum head 350 cubic inch TPI Corvette engine. B2L means an iron head 350 cubic inch TPI F-body engine. That's the difference. The F-body has both because the B2L changes the L98 designation into an F-body engine from the Corvette engine.

Of course the LT1 is superior to the L98. Anyone who argues that is a fool. The LT1 has better heads and better intake. What we're saying is the L98 is cheaper to mod, and responds just as well to mods, up to a certain point. Then the long runner intake kills off the horsepower potential. However, throw an upgraded short-runner intake onto an L98, such as a SuperRam, MiniRam, or StealthRam, and you have all the power of an LT1 with a fraction of the cost.

So which is better? It all comes down to your preference. Drive both and see what you like. The LT1 will be a newer, faster car, but it will also cost more to insure, and cost more to modify. The L98 will start slower and older, but the money you save will allow you to modify it.

5.0L Mustangs and 4.6L Mustang owners do argue amongst themselves over which is better. However, the 5.0L to 4.6L changeover was a sideways move, whereas the L98 to LT1 changeover was a step upwards. And the LS1 was an ever bigger step upwards. Ford had to add a blower to their 4.6L engines to get them to LS1 power levels.

 

My l98 bone stock with 3:73 gears ran 14.34. here is a ist of the mods I had: zz4 cam 487 510 lift. ported heads,slp runners,ported intake, ported plenum,slp 1 5/8 headers. flowmaster exhaust . 10:1 flat top pistons. I had the tranny built , it also had tpi tech 24lb injectors. The best it every ran was 13.7's . Now that was alot of shi@ to just pick up 6 or 7 tenths. Now you are still missing the point. You can take a l98 pull the tpi off. Port those heads stick a carb on it with the same cam I am running and there is no way it will run in the 11's. NOt even close. And I might seem a little up tight about this but you are the one that called me a idot and it is clear that you are the one that knows nothing about making power because if you did you would understand that not only the intakes on the l98 motors hold them back but that the heads just dont flow. And you talked about the corvete heads? They dont flow much better. Do your homework show me a tpi corvete that makes the earth shake. It just doesn't happen. Please do me a favor spend thousand's of dollars on a tpi with upgraded vortech heads all the bulls@#! and then put a supercharger on it a come run me. Because you still wont be able to stay even close. That is a open race invite to all tpi owners. See you all next spring. Still waiting for you to show me some 9 or 10 second tpi's. Must be having a hard time finding them. But yet you said that if you did the same to them as a lt1 that they would run the same. Should be a bunch of them out there hu????

 

Did you mean idiot?

 

Hey 91rsrider,

Glad we can discuss things in a civilized manner. Just wanted to throw out that I don't really consider heads and cam to be bolt on items since you have to get into the internals of the motor. If it doesn't require removing the valve covers, it's a bolt on (except rocker arms, they are bolt on).

Hey guys, it's not just peak flow numbers that make power. It's really more of the mid range flow where you see your power. How long does an valve stay open at peak lift? Not long, however it's open for quite a bit in the mid range while it's opening and closing.

One other thing, didn't some mag do a story comparing the L98 aluminum vette heads to a pair of vortec iron heads a while back? I remember seeing something about it, but I didn't get to read the article. Maybe someone has that story hidden away somewhere. It would be interesting to see how they compared since the vortec heads are based on the LT1 heads.

 

You say TomAto,I say TomAHtoe! My cars better than your car! neener,neener! Apples ,and oranges,and a Grapefruit,will this ever end? Technology will always win,and technology is always obsilete,but is always improving,getting better. Does this mean what you bought yesterday is junk,I think not,just older technology. What most of the TPI people are saying is mod ,for mod you will improve the same as the mod's to the LT1,you won't gain on or lose performance,and yet they try! That is what it is all about,like I care that someone has a faster car,or newwer motor than me,hell yes I care that's why I will keep-up my relentless searce for more HORSE POWER,that's hot rodding,that's what counts.

Oh yeah! And beating the pants off of them critters that challenge our F-BODIES.....Do I hear an A-men?

 

Amen brother.

Ps... I ROCK!!

 

There are some fast TPI cars out there, you just gotta look. Assuming that there isn't is just stupid. LT1s are not some kind of incredible wow improvement over L98s. It's true they don't feel as fast as L98s, but LT1s are only a few clicks faster and do lose to L98s on occasion. And I've met a few overly problematic 1's too. An L98 is a better place to start than an LT1 because of it's simplicity and available choices.

Wanna race this TPI? www.tpi305.com

 

No, I don't really want to try racing that TPI yet. Technically, it's not a stock 305 block.

Bowtie 4.025” bore x 3.0” stroke-305 cu/in.

Yeah, it's 305 inches, but it's a 350 bowtie block that's been destroked.

Also, when you start talking about forced induction, intake limitations are not quite as big a deal.

I'll kill'em if my GTA is ever completed.

 

Wasnt the LT5 TPI?
If so, let the LT1 guys race that one hahah.

 

Hey guys can't we get along as I said in my previous post when the mods start all bets are off. It should be common knowledge that the LT1 is a different and better design than the L98 from the heads up earning it the term Gen II SBC. I'm just waiting to install a set of AFR heads hotter cam and HSR. Then the L98 does compare. It just doesn't have the Opti crap. So what I'll stick with tried and true. As far as cooling I've never seen anything to prove the performance gains with reverse flow cooling. But I've seen many an overheating LT1.

 

come to think of it i think it was a shorter version of TPI.the runners were probably close to 75% of the length of TPI runners.still shorter than an LT1.

 

LT5? TPI? Have you ever seen one? It's a dual runner design! Absolutely no comparison. Just because the runner tubes look similar doesn't make it TPI.

And to jonesy91z28: Just because your car runs like a$$ doesn't mean all TPI's must. You had bad luck with yours, as I've seen a true bone stock 91 Formula run a 14.2@97MPH. Just a custom CAI, headers and full 3" exhaust with an 85 Vette torque converter it went 13.4 on street tires. Either you can't tune, can't drive, or have a something mechanically wrong with the car. My guess is all 3

I've also seen carbed ZZ4s (almost identical to your setup) running 12s. The ZZ4 components were not designed with TPI in mind.

And what's with the focus on TPI anyway? The topic is about thirdgens, not TPIs. Last time I checked thirdgen cars came with several different induction setups. Besides, the fastest thirdgens are carbed - no argument can be made about that.

And to whoever claims they don't see any fast TPIs here: Most dedicated racers I know don't visit message boards like these. Don't limit your perspective to an LT1 oriented internet site...

 

whoa whoa settle down man i wasnt implying that the LT5 is TPI.i just remember there being 2 runners per cylinder,and that they were TPI-esque in appearance.are you sure that the runners arent tuned though?if they are then surely it would be TPI i would think,just not L98 TPI .

 

All fuel injection intake runners are tuned. Otherwise they wouldn't work very well would they? Chevy just coined the phrase Tuned Port Injection for their new V8 EFI in 85.