90qzrblu

Well....I had my first ride in a ZR1 yesterday, courtesy of Lowflight... :seeya

I let him do the flogging on the backroads. All I can say is :eek: :eek: Wow, what a car! I was amazed at how the slightest acceleration pushes you back in the seat! The noises that the car makes while accelerating is just absolutely amazing! :thumbs: The ZR1 is intoxicating...

I went and drove my L98 later yesterday evening as a comparison...and well, there is no comparison. My car that usually feels like a sprinter was reduced to a whimpering dog, tail tucked and all.

So, here's my question to those that have modified L98 or LT1 cars. It's not hard to equal the output of a ZR1, but will it give me a similar feel of power compared to the ZR1? I don't think that the sounds and aura could be replicated, but is that push-me-back-in-the-seat whoosh something that I can recreate with more power in my L98 car?

I really do love my car. It's a beautiful car for its age. But this ride in a ZR1 reinforced my desire for a 6 speed and more horses.... :yesnod:

What say ye, O wise C4 sages? :seeya

scorp508

ZR1 has the best of both worlds with those secondaries. Long tubes for low end and massive air intake for the top end. It just makes torque and hp all over the damn place and into the atmosphere for RPM range.

90qzrblu

Yeah, it pulled so strong everywhere in the rpm range! It took a few shifts to get the feel of the gas and clutch. I didn't want to spin them and give his paint some scratches....Lowflight's car is very clean.... :yesnod:

Aaron71771

I would think any 400hp vette is going to give you a rush. With those 21' runners on the L98 any mod work is going to show up in the low end grunt of the car, which is usually a good thing.

The LT5 just moves tons of air with it's 16 ports and 32 valves. One would think as a car moves past 100mph the limts of a car start to come into focus, at least a little, no so with the ZR-1. The faster you go the harder it runs. These things are like freight trains going downhill.

jimb500

The key is always the same, airflow. The more air you push, well, you know.

86VETTEMAN

To answer your question, Yes, you can recreate that feeling in your car. I think you can even surpass the ZR1. At least you can get more tourque ie. "The push back in the seat feeling". Don't get me wrong, I'd kill to have a ZR1 but, I prefer the good ole push rod V8 (potential of more torque). So I believe you can surpass the ZR1 in low end power.

Aaron71771

What does the engine design have to do with torque output??? I would think the traditional V8 and DHOC design would both have equal potential for torque. Of course the advantages of dual runners are self evident over single runner design.

The difference between a 91 L98 and 91 LT5 is what? 35ft/lbs of torque. Seems to me there is more to the feel of the LT5 then 35ft/lbs. Of course there is peak torque vs. torque over time to consider too. Would you rather have a car that makes 300+ ft/lbs from 1500-7000 RPM, or one that makes 400+ft/lbs 4000-4500 RPM?


[Modified by Aaron71771, 2:03 PM 4/4/2003]

86VETTEMAN

Push rods will naturally produce mor toque. The Z06 is a good example. Same horses but look at the torque value. As for the 35 foot lb difference between the L98 vs. ZR1, Thats 35 lbs. more tourque with over 100 HP. less. Even the HP with one another then see what the difference in torque is. There is no arguing. Push rods produce more torque and DOHC produce more top end HP. Like you said, It's all in what you want your power range to be. I like 1/4 mile racing myself. DOHC would not be the choice for me.

Aaron71771

Can you please explain how? Is the LS6 torque due to push rods or technology?

You still have one design using a single runner, which is going to comprimise either on the low end (LT1) or the high end (L98). A dual runnder design is able to overcome this. Of course this may be a seperate issue from base engine design.

Isn't the HP that a DOHC engine produces just an indicator of that engines ability to produce torque at higher RPMs?. I don't understand how that has anything to do with that engine ability to produce torque at lower RPM's. The only thing I can think of is in a lower RPM band, it would take more energy to get all the parts moving in a DHOC, but that is just a guess.

ShawnZR-1

This statement escapes me. My 1991 Z (from the factory) Produced 375 HP and 370 ft/lbs at the crank. The first LS6's (trying to compare apples to apples) produced 385 hp with 385 ft/lbs due in a large part to a much lighter rotating assembly.
Here's a stock LS6 Dyno:


and here's my lt5's dyno with just exhaust:


Seems to me the LT5 makes more torque longer and that's what matters, the area under the lines, not the peak itself.

I'm not trying to flame or anything, I'm just trying to figure out how push rods alone would make more torque :confused:

86_RedRider

gravity, duh! :jester :lolg:

86VETTEMAN

Look at the Z06. Why are the LT5's doing less torque vs HP. The Z06 has 405 hp and 425 lb ft of torque. I am not saying the LT5 dose not produce enough torque, I am saying it doesn't produce more tourque than horse power like a push rod does. Ask yourself, how many top fuel drag cars use DOHC? How may ralley cars use push rods? The ZR1 is an autocross car because it produces power in the upper rpm's. The early C4's, although theoretically should be autocross cars, are great for 1/4 mile runs. DOHC will get you more top end HP because they will move the air through the engine faster, I mean come on, you have 4 cams for Pete sake! Push rods will not move as much air but can create a lot more torque. Like I said, I am not knocking ZR1's, I love them and I am not saying that the ZR1 doesn't have torque. I am just stateing that push rods usuall have more torque than HP. Where as DOHC will have equal or a little less torque than HP. Thats all

vader86

Anyone on here should know that DOHC has the potential to equal pushrod in terms of torque output, it just depends on the design of the cams. Pushrod can also equal DOHC in terms of HP output, also depending on the design.

Pushrod technology is just cheaper and easier for GM to use right now, so theyre sticking with it for the time being. DOHC will be standard in vette engines one day, but that day may be a long time in coming.

There was an extensive thread on this in C6 Discussion.

86VETTEMAN

:cool: Nice mediator man! I guess then every one is right!

GDP

Try some longtube headers and big blower. Also, 4.10 in the back won't hurt either! :steering:

robertpel9

ZR-1 owners RELAX. We all like your cars. There is some validity to the argument here but its no reason to write a book about it. Can you build an L98 up to kick an LT-5's butt. Sure but its gonna cost money. If you put money into the LT-5 you will make great gains as well and you are starting out with a higher performance motor to begin with. Geesh it seems owners of certain vettes (ZR-1's in particular) are very protactive about every littelt thing with their car. WE LIKE THEM THEY ARE NICE. I would rather have a convertable so i cant have an LT-5 under my hood but thats just me. Lighten up everyone.

sraft

The torque and HP curves are a product of the top end's ability to flow air, and not determined by the method by which the valves are operated.

383 Stroker

I've got the 383 stroker motor under the hood which puts out some ridiculous amount of power...take a look at the sig below. I've raced a stock ZR1 before and kept pulling away from it all the way up to 120 mph.

As for the sound my car makes, it sounds like a big block from hell. It's got that loud, lumpy, throaty sound you would expect from a sports car! :thumbs:

fourthgencorvette

you can build your L98 to outrun a ZR1, no problem. But anything past the 1/4 mile the ZR1 will stomp that choke your chicken TPI intake.

If you want to run with the ZR1 on a top speed run, you need a miniram II, cam, heads, gears, and exhaust.

I've beat my fair share of ZR1's on top speed runs, but im in a league where only a few are at.

But I love all Corvettes!!!!!!!!!!!!!!!!

:chevy

90qzrblu

Hey, 383....

I had your car as my wallpaper for a while. I got the pic off of idavette.net, the place that led me here. Sweet ride... :cool: :cheers: