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Why did the ZR-1 have to be heavier?

Old 11-07-2018, 04:04 PM
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Originally Posted by Zak2018 View Post
Ok, thanks. I didn't think it would be this complicated. I will have to dig out a manual then. Are there production numbers somewhere showing the number of manuals produced each year of the C4 run?
It's out there somewhere on the webernets. ZF-equipped C4s aren't that rare, since a couple years of L98s and five years of LT cars could be ordered with ZFs.

OK. Maybe what I'm thinking are hard tops are just targas with body color covers as opposed to the black glass. Pity. Wish there were hard tops.
Yes, you could get a C4 with either the body-colored fiberglass targa top or the acrylic "glass" top, but both are bolt-in targas. Some cars came with both. But there is no fixed roof at all.

Not too bad. So basically a LT. But would it keep the L98 bottom torque characteristic and great sound? If so, then I would have a LT with bottom torque instead of the LTs higher rev. Sounds good to me. For the road I think bottom end torque is where the fun is at.
So Tom really addressed the torque thing. With a short-runner intake you'll have the same off-idle torque, but a flatter torque curve and a wider rpm range to use, and no hump in torque at 3000rpm like with the TPI intake. Overall it's a better set of characteristics in every way.

I need to recant my last estimate of power on that combo, though. When I typed that post, for some reason I was forgetting that the L98 heads probably don't flow quite as well as stock LT1 heads, and the L98 will have a little lower compression ratio. So let's bump that estimate down maybe 310chp. Sorry for my brain fart there. If others disagree with my estimates, I hope they'll chime in.

And all of these would be just bolt ons right? And idle stock?
Well, a cam is a "bolt-on" in the sense that you don't have to pull the engine and tear it down, but does require the intake to be removed. The idle will still depend on the cam, and I don't have the expertise to advise you on exactly what grind you'd want. But you can get something that will bump the power a bit and still idle pretty much like stock. Hell, even the original LT4 cam was a significant improvement on the power of the L98 grind.

I wonder why people complain about the L98 and rave about the LT1 and prefer LT1 cars then. Unless this is expensive or difficult to do, seem to me like a non brainer. Unless the person either likes the new styles which comes with the LT1 engine or maybe have plans to increase hp and starting at 300 hp is better.
The answer(s) to that is long and debated. But suffice to say that a stock L98 is much less powerful and has a narrower range of useful rpm than the LT1/4. Stock for stock, the LT is a real improvement. And it even got better mileage to boot.

OK. And [a stroker 396] would still idle stock and get me around 400chp? So basically late ZR-1 power in a lighter car.

All bolt ons? Bottom torque still there? L98 sound?
A stroker can get those numbers with a stockish idle, yeah. So can the 400 engine that Tom mentioned earlier (still a small block, but built originally as a 400 with a larger 4.125" bore and a 3.75" stroke). Again, a stroker kit is not a bolt-on. It will be a full engine removal and rebuild, using a different crank, rods, and pistons.
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Old 11-07-2018, 06:41 PM
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46,061 Manual 6-speeds from 1989 to 1996
31,434 Manual 4-speeds from 1984 to 1988

286,685 Automatics from 1984-1996
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Old 11-07-2018, 07:25 PM
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Originally Posted by Zak2018 View Post
I wonder why people complain about the L98 and rave about the LT1 and prefer LT1 cars then.
Regarding this comment, I'll add to what Matthew said:
*1000+ more usable RPM. The L98 is a fun ride...up to 4000-4500 RPM. That number...that spot on the tach comes up quick in lower gears and it feels limiting. Frustratingly so, IMO. You talked about "L98 sound". IMO, when you shift a stock L98 where you need to for max acceleration, you ear is left wanting -it feels/sounds like you're short shifting. If you don't look at the tach and just wind it out by ear...you end up spending a lot of time in "no man's land" where you're burning gas but not making any power.
*No penalty -you get 50 more hp, the same tq essentially, the aforementioned 1000+ more usable RPM....AND you get better fuel economy. What's not to like?

The looks would be about the only thing that I can think of.
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Old 11-08-2018, 11:42 AM
  #84  
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Originally Posted by Tom400CFI View Post
1. The LT1 actually makes more bottom end torque than the L98.

[img]http://i14.photobucket.com/albums/a3...owertorque.jpg



2. All of the things Matthew is suggesting are bolt ons. Idle is defined (mostly) by the cam and tune
3. There is no difference in "sound" between an L98 and an LT1...or any other Gen I/II engine other than that sound which is created by the exhaust system and other engine changes (cam/compression). IOW, the intake doesn't define the sound. Any difference that you're talking about in and "L98 sound" is due to the L98's (single) exhaust system vs. the LT1's (dual) exhaust system. In any case where you're going for 300+hp, you'll ditch the L98's stock exhaust for something better and you'll no longer have the "L98 sound"...whatever that is.
Thanks. It seems my research is not to be trusted. This is why it's better to get info more directly from people with experience with the cars, such as the people here at the forums. In my research I found several people saying the L98 has more bottom torque while the LT1 revs higher. Also several people saying they prefer the L98 sound and even praising it. Then I searched for a few clips on YT and kind of thought the same based on the clips I saw. Of course, exhaust set up play a huge role and "nicer" is a subjective thing. But maybe the comparison is stock vs stock.

But thanks for clarifying the torque issue.
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Old 11-08-2018, 11:49 AM
  #85  
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Originally Posted by bb62 View Post
46,061 Manual 6-speeds from 1989 to 1996
31,434 Manual 4-speeds from 1984 to 1988

286,685 Automatics from 1984-1996
Thanks. So less than a 1/3 of the cars were manuals.

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Old 11-08-2018, 11:58 AM
  #86  
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Originally Posted by MatthewMiller View Post
Yes, you could get a C4 with either the body-colored fiberglass targa top or the acrylic "glass" top, but both are bolt-in targas. Some cars came with both. But there is no fixed roof at all.
Do you think there could be considerable chassis stiffness gains by making it a fixed roof?


Originally Posted by MatthewMiller View Post
So Tom really addressed the torque thing. With a short-runner intake you'll have the same off-idle torque, but a flatter torque curve and a wider rpm range to use, and no hump in torque at 3000rpm like with the TPI intake. Overall it's a better set of characteristics in every way.

I need to recant my last estimate of power on that combo, though. When I typed that post, for some reason I was forgetting that the L98 heads probably don't flow quite as well as stock LT1 heads, and the L98 will have a little lower compression ratio. So let's bump that estimate down maybe 310chp. Sorry for my brain fart there. If others disagree with my estimates, I hope they'll chime in.
Ok, so between the 98 with better intake, very mild cam, and maybe headers you suggested and the L98 built as a 396 (or is it 383?) and the 400 engine that Tom mentioned earlier , which one would be the easiest to do? Cheapest? And which would be preferable and why? It seems one of these 3 options might be the best way to get what I want, which is a 1990 C4.

Unless I find a very nice 1990 ZR-1 for a great price, full service history etc.
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Old 11-08-2018, 12:00 PM
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Originally Posted by Tom400CFI View Post
Regarding this comment, I'll add to what Matthew said:
*1000+ more usable RPM. The L98 is a fun ride...up to 4000-4500 RPM. That number...that spot on the tach comes up quick in lower gears and it feels limiting. Frustratingly so, IMO. You talked about "L98 sound". IMO, when you shift a stock L98 where you need to for max acceleration, you ear is left wanting -it feels/sounds like you're short shifting. If you don't look at the tach and just wind it out by ear...you end up spending a lot of time in "no man's land" where you're burning gas but not making any power.
*No penalty -you get 50 more hp, the same tq essentially, the aforementioned 1000+ more usable RPM....AND you get better fuel economy. What's not to like?

The looks would be about the only thing that I can think of.
Ok. But I guess with the mods Matthew proposes for the L98 that would change and be a nice engine it seems.

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Old 11-08-2018, 12:13 PM
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Originally Posted by Zak2018 View Post
I found several people saying the L98 has more bottom torque
People do this constantly and IDK why. We are seeing more of this behavior than ever, in politics right now; the facts are clear, but someone states a falsehood as fact. WTF? IT sucks b/c it does nothing but muddy waters that could and should be clear. Why do people think this about the L98? I think two reasons;
1. When the L98 came out, tq was a dramatic increase over any small block before it -especially at low - mid RPM. No carb'ed SBC before had anywhere near the tq that the L98 had in '85. So it made an impression on people that may have "stuck".
2. Torque is all the L98 has got to offer! So if you own one, that is what you focus on and talk about. 230-245hp @ 4000-4500 isn't what you talk about. So people talk about the "tork monster TPI", instead. Both the LT1 and the L98 made ~340 tq peak, so...



Originally Posted by Zak2018 View Post
Do you think there could be considerable chassis stiffness gains by making it a fixed roof?
YES. How to do it? IDK.




Originally Posted by Zak2018 View Post
which one would be the easiest to do? Cheapest? And which would be preferable and why? It seems one of these 3 options might be the best way to get what I want, which is a 1990 C4.
I like the 400 for the bore and cost. Matthew likes the 396 b/c he's in a different situation; he is limited by the "LTx" platform to a 4.0" bore so to get the cubes, he has no choice but to go w/a longer stroke. That works, and works awesome. But if you buy a '90, a 400 is nearly a bolt in. The one hang up is the flywheel which you can have a machine shop fix the flange and balance to run on a 400.

It all boils down to what's more available and cheaper in your area; a 400 block? Or a 3.85" crank?

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Old 11-08-2018, 12:24 PM
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And by the time you do all this work, you could have easily bought a ZR-1 with headers on it (400hp) for nthe same money or less...

Heres the deal of the century....

https://www.ebay.com/itm/1993-Chevro...2:pf:0&vxp=mtr

Last edited by 81c3; 11-08-2018 at 12:26 PM.
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Old 11-08-2018, 02:28 PM
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Originally Posted by 81c3 View Post
And by the time you do all this work, you could have easily bought a ZR-1 with headers on it (400hp) for nthe same money or less...

Heres the deal of the century....

https://www.ebay.com/itm/1993-Chevro...2:pf:0&vxp=mtr
yeah, but I heard it will need to be run out at full song to get its worth. Tow truck L98 for the win. Imagine the torque of a full tpi setup stock in a 400 block with 400 crank? The TOWAK would be insane for 2,000 rpms of power band and idle insanely nice.
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Old 11-08-2018, 02:29 PM
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I'm interested in the 93. Can't remember the name right now, but sounds like it is the ICM version of the LT5? At least I think that is why it's stalling.

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Old 11-08-2018, 02:45 PM
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Originally Posted by 81c3 View Post
And by the time you do all this work, you could have easily bought a ZR-1 with headers on it (400hp) for nthe same money or less...

Heres the deal of the century....

https://www.ebay.com/itm/1993-Chevro...2:pf:0&vxp=mtr

You probably said the same thing when it sold at BJ in sept of 17 for the same hammer price of 14,000. 15,400 after buyers fees.
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Old 11-08-2018, 02:45 PM
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Originally Posted by 1993C4LT1 View Post
I'm interested in the 93. Can't remember the name right now, but sounds like it is the ICM version of the LT5? At least I think that is why it's stalling.
Nice car for sure. He who hesitates....

Last edited by pologreen1; 11-08-2018 at 02:48 PM.
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Old 11-08-2018, 02:48 PM
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Originally Posted by 1993C4LT1 View Post
I'm interested in the 93. Can't remember the name right now, but sounds like it is the ICM version of the LT5? At least I think that is why it's stalling.

Primary fuel pump is probably dead. Secondary pump runs for a bit at start up and then turns off. An easy cheap fix, but the car probably has a few other needs as well.
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Old 11-08-2018, 07:01 PM
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Originally Posted by Zak2018 View Post
Ok, so between the 98 with better intake, very mild cam, and maybe headers you suggested and the L98 built as a 396 (or is it 383?) and the 400 engine that Tom mentioned earlier , which one would be the easiest to do? Cheapest? And which would be preferable and why? It seems one of these 3 options might be the best way to get what I want, which is a 1990 C4.
The 350 with intake, cam, and headers is easier and cheaper by quite a bit, but less powerful. Either the stroker kit or the 400 engine will provide significantly more power for the same idle quality. I honestly don't know enough about the 400 option to advise. I think you have to drill two cooling passages in the heads to make the 400 block work with them, too, due to the siamesed water jackets. Tom can probably confirm that (or not). I do know more cubic inches for the same size/weight engine is pretty much always better. One other thing I don't know about on an earlier L98 car is how much tuning the ECM would need for the bigger engines. I'm not really sure.

As for which option makes more economic sense, only you can answer that one. Of course the cam/intake/headers on a stock L98 is a much cheaper option than a ZR1. As for the big-inch engines, it depends a lot on how much labor you can put in yourself. If you buy a clean L98/6sp C4 for, say, $6k and then spend another $2-3k for a big-inch engine and do the work yourself, your still in it for a lot cheaper than a ZR1. If you have to pay someone else to do it all and then you might quickly get up to the cost of buying a nice ZR1.
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Old 11-08-2018, 07:04 PM
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Originally Posted by ChumpVette View Post



You probably said the same thing when it sold at BJ in sept of 17 for the same hammer price of 14,000. 15,400 after buyers fees.
I more than likely would have if Id seen it.... Why, do you consider it a poor deal for a 93 ZR-1 in that particular color combination?

Last edited by 81c3; 11-08-2018 at 07:20 PM.
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Old 11-09-2018, 06:56 AM
  #97  
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Originally Posted by Tom400CFI View Post
People do this constantly and IDK why. We are seeing more of this behavior than ever, in politics right now; the facts are clear, but someone states a falsehood as fact. WTF? IT sucks b/c it does nothing but muddy waters that could and should be clear. Why do people think this about the L98? I think two reasons;
1. When the L98 came out, tq was a dramatic increase over any small block before it -especially at low - mid RPM. No carb'ed SBC before had anywhere near the tq that the L98 had in '85. So it made an impression on people that may have "stuck".
2. Torque is all the L98 has got to offer! So if you own one, that is what you focus on and talk about. 230-245hp @ 4000-4500 isn't what you talk about. So people talk about the "tork monster TPI", instead. Both the LT1 and the L98 made ~340 tq peak, so...
I think your theory here explaining why the L98 has this bottom torque reputation makes a lot of sense.



Originally Posted by Tom400CFI View Post
YES. How to do it? IDK.
How about two pieces of metal on each side in between the targa top, connecting the frame? Then fix the top on top of that?




Originally Posted by Tom400CFI View Post
I like the 400 for the bore and cost. Matthew likes the 396 b/c he's in a different situation; he is limited by the "LTx" platform to a 4.0" bore so to get the cubes, he has no choice but to go w/a longer stroke. That works, and works awesome. But if you buy a '90, a 400 is nearly a bolt in. The one hang up is the flywheel which you can have a machine shop fix the flange and balance to run on a 400.

It all boils down to what's more available and cheaper in your area; a 400 block? Or a 3.85" crank?
No idea. I would have to check. Chances are I will have to order online no matter what.

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Old 11-09-2018, 07:03 AM
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Originally Posted by MatthewMiller View Post
The 350 with intake, cam, and headers is easier and cheaper by quite a bit, but less powerful. Either the stroker kit or the 400 engine will provide significantly more power for the same idle quality. I honestly don't know enough about the 400 option to advise. I think you have to drill two cooling passages in the heads to make the 400 block work with them, too, due to the siamesed water jackets. Tom can probably confirm that (or not). I do know more cubic inches for the same size/weight engine is pretty much always better. One other thing I don't know about on an earlier L98 car is how much tuning the ECM would need for the bigger engines. I'm not really sure.

As for which option makes more economic sense, only you can answer that one. Of course the cam/intake/headers on a stock L98 is a much cheaper option than a ZR1. As for the big-inch engines, it depends a lot on how much labor you can put in yourself. If you buy a clean L98/6sp C4 for, say, $6k and then spend another $2-3k for a big-inch engine and do the work yourself, your still in it for a lot cheaper than a ZR1. If you have to pay someone else to do it all and then you might quickly get up to the cost of buying a nice ZR1.
Thanks. Something is telling me I would probably just do the 350 with intake, cam, and headers etc and be happy with the 310chp. Or just buy a ZR-1 if I can find one in good condition and for a good price. If it gets too complicated to do and expensive, given everybody is saying the ZR-1 is reliable, despite the gamble if it does break, it would probably still make more sense to go for the ZR-1.Before spending a lot of money and time in modifying the engine too much etc. As long as I can find a cheap enough ZR-1 and in good condition.

Because I think I would be able to do the 350 with intake, cam, and headers myself. But I'm not a mechanic. So the more complex stroker project I might have to get help. With the 400 it seems I definitely would need to pay somebody.
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Old 11-09-2018, 09:36 AM
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Originally Posted by Zak2018 View Post
Thanks. Something is telling me I would probably just do the 350 with intake, cam, and headers etc and be happy with the 310chp. Or just buy a ZR-1 if I can find one in good condition and for a good price. If it gets too complicated to do and expensive, given everybody is saying the ZR-1 is reliable, despite the gamble if it does break, it would probably still make more sense to go for the ZR-1.Before spending a lot of money and time in modifying the engine too much etc. As long as I can find a cheap enough ZR-1 and in good condition.

Because I think I would be able to do the 350 with intake, cam, and headers myself. But I'm not a mechanic. So the more complex stroker project I might have to get help. With the 400 it seems I definitely would need to pay somebody.
Or you could do a good a 350 with a good set of heads, cam, headers, open exhaust, 1;6 rr's and use the shorter intake platform of the lt1 style and make 425chp and still be streetable. This has been done for decades now and 10's of thousands of GM cars from the 89'-90's and back.

Someone posted a link here the other day of a crate 420chp 350. The factory is now offering a bolt on built motor, so they are decades late to the party, but not as many people wrench anymore either, and nobody is happy saying they have 250hp these days in a "sports / performance car" Of course wiht this combo or any that improves HP you need to consider rear gear and trans combos. More hp equal lower gears to make it happen based on physics. Unless you built an awesome hybrid intake combining the lt1 with the l98 of course.

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Old 11-09-2018, 09:59 AM
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Originally Posted by pologreen1 View Post
Or you could do a good a 350 with a good set of heads, cam, headers, open exhaust, 1;6 rr's and use the shorter intake platform of the lt1 style and make 425chp and still be streetable. This has been done for decades now and 10's of thousands of GM cars from the 89'-90's and back.

Someone posted a link here the other day of a crate 420chp 350. The factory is now offering a bolt on built motor, so they are decades late to the party, but not as many people wrench anymore either, and nobody is happy saying they have 250hp these days in a "sports / performance car" Of course wiht this combo or any that improves HP you need to consider rear gear and trans combos. More hp equal lower gears to make it happen based on physics. Unless you built an awesome hybrid intake combining the lt1 with the l98 of course.
Yeah, but that crate engine or any other 350 that really makes 425chp isn't going to idle anything close to stock.
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