RC000E

I'm wondering if in hindsight any people have decided on a true preference between the L98 cars and LT1 cars. My personal preference is the newer body style and 6speed only cars, so I'm trying to make the best decision.

Through reading I've considered:

92+ has the LT1, more power, better improvements on rattles and things associated. Has opti spark issues and others?

91+ have the L98, but I've heard there's more in the aftermarket...I'm not convinced but an wondering what more informed minds have to say on the subject. Less power, but are these more build friendly for any reason?


My background is pretty intensive in racing, fab, headporting, EMS tuning, etc. So, it is likely while my car may stay stock or lightly modded for a short time I'll either be building a custom forced induction setup or be doing some various N/A setup. So, I'm curious which has the more affordable management solutions and which is the better starting point.

Internally speaking, what are the advantages of the LT1 versus the L98? The ZF trannies were no different I assume, is this correct?

Lastly, wiring aside, how much different are the LT1's versus the L98's when considering swapping the motors (LT1 into 91). Are there mount differences, bellhousing boltup issues, etc?

Any info you can lend....thanks ahead of time.

turbopezz

Both are good platforms,they made a black tag and blue tag trans.The early black tags are stronger.I am not sure when the blue tag was used but it might be 92 or 93 . Tune ports are just fuel injected SBC so its easier to find performance parts used and say a 400 sbc ... Lt1's are a little more limited but nicer from the factory.

I have A 91 vette wanted the newer body update but with the regular SBC.

BrianCunningham

If this is the one you want to turbo

Get an earlier car with the standup radiator

More room

jrzvette

Black tags were used until somewhere in the middle of the 93MY. I have a black tag in my 93 and the VIN is not quite the half way mark.

As far as the L98 vs LT1, both are good engines. To some, the L98 seems a little quicker off the line but it runs out of steam around the 4800 RPM mark. If most of your driving will be on the streets you'll have to ask yourself how often to you plan to redline the car. I don't race my car so I rarely go above 5000 RPM in any gear except 1st.

Tom400CFI

The guy is going to mod (a lot) it sounds like, so stock to stock comparisons and driving characteristics are kind of a mute point.

Both are highly modifiable and easy to work on

Both have the same block dimensions, engine mounts and bell housing flange.

LT1 has reverse flow cooling, fron mount dist, and gear-driven water pump so "top ends" are not practically interchangable.

Both are cheap to swap, upgrade, etc.

Wiring is not 'interchangable' engine to engine with out modification

Internally speaking, I don't think there is one advantage over the other. The LT1 makes more power b/c of the intake and heads.

I have a very strong running stock '92 6 speed ("Black tag") that I'm going to sell b/c I want a '91. I want a '91 b/c I want to go down the SBC 400 road and it will be way easier starting w/the '91.

Dudeurgettnavette

92!

traxx1

I picked the 91 with 6speed, engine wise the first gen sbc ended in 91 and you can find stock to wild crate engines for the first gen, Jegs sells a first gen 405 hp fpr about 3k

RC000E

Well, my intentions may very well be to mod lightly (headwork, custom headers, tuning, etc) in order to truly familiarize myself with these cars and this platform. Within a year to two years is likely when I'll do the custom FI setup in order to create jigs and develop a repeatable setup.

So, in essence I would like something to build in both realms...mild and wild I guess you could say.

If the LT1 is basically due to the development of heads and cam, then the L98 with the guaranteed strong tranny sounds like the way to go. I've got a lot of experience working with 4valve/cyl castings in terms of headwork, so improving the L98 heads and doing a cam sounds like the ticket to be in the same arena as the LT1 guys.

Do the L98's have forged pistons from the factory?

mnstrlt1

no question about it. The 91 and earlier cars will have much more aftermarket support due to the Gen-I engine. the Gen-I is not the only benefit here, it's also because companies like world castings, brodix, and a few others actually make an aftermarket block for huge cubic inch potential (450+ cubic inches).

the aftermarket head selection is also nearly unlimited. You can go with traditional 23 degree heads (which AFR seems to be the "king" of), or you can go with wild (exotic) castings such as 18 degree or 15 degree heads.

Finding aftermarket heads for gen-II is a different story. You're read the occasional thread about somone converting Gen-I heads for Gen-II use, but this really isn't cost effective.

After talking to Bill (zfdoc.com) he mentioned to me that the "blue tag, black tag" actually indicated the location that the transmission was manufactored. The nearlier cars (89'-93') got the "black tag". what this really means is that the gears themselves and the materials used internally are considerably stronger than the later cars (94-96'). The earlier transmission had the center section of the gears welded to the gear itself, the newer transmission used a clip to retain the center section to the gear. the pitch of the teeth are also slightly "improved" to reduce noise.

Bill can blue print and rebuild either one to hold 800rwtq or more.

mnstrlt1

a decent H/C/I/E and storker is capable of 450 rwhp (this is not uncommon AT ALL).

if you go "b@lls to the wall", you'll find a few monster small blocks in this community... 434's, 427's, 461!!!!

the guy with the 461 recently added a set of serious 23 degree heads and pumped out 650rwhp!!!!! I'll take one of those! lol...

Blue 92

It was tough.

250 HP or 300 HP

Hmm....

RC000E

Sounds like the 91 is the ticket based on that statement.

My familiarity is truly to that of 4valve/cyl heads, pentroof chambers, all aluminum motors, etc. So, getting into this world will be a bit of a change, but a change is definitely what I need at this point.

Time to start some reading and get it together. I truly thought the LT1 cars were the step up, but after catching several small hints towards the earlier cars in other threads I figured I'd look into it further. Works for me though...91's are cheaper...lol and no optispark hassles to bite me early!

I have an NX wet kit sitting right in the shop here that'll make up for that LT1 difference right out of the gate with no problem. From there it just seems there's more possibilities which is what I'm looking for.

Now I just need to battle through selling my own car in this tough market in order to get the funds to buy the Vette. Hopefully it won't be too long.

aboatguy

You forgot 95 or 96 they have a better opti.

400 plus rwhp is not hard on factory shortblock with LTX engines.

MIke

RC000E

Yeah, I read a good bit on the Opti to be prepared...lol.

Pistons info via search:

1985 = Forged
1986-1989 = Dished Cast
1990-1991 = Flattop Cast

RC000E

I sure hope so, we've been making 600whp+ on stock 1.6liter Honda shortblocks for years with forced induction. I assume you meant N/A though.

I would imagine the LTX can make a lot more than that forced.

mnstrlt1

I've been following a few of you're posts and the obvious assumption is that you're from the Honda camp?

The inline motors will tolerate boost much better than v-layout engines. the pistons have to deal with side loads in the v layout. Even though the honda's are typically open-deck block's, they do relatively well with ridiculous amounts of boost (oh, and money). this is also why the inline 6's (i.e. rb26dett, 2jzgte) do incredibly well udner boost.

Keep in mind, most domestic car owners talk about power with a completely streetable package (at least on this forum, and unless stated in NA form). Not an inline four running c16, 20+/30+ pounds of boost, needs to be rebuilt regularly, runs a solid transaxle making turning impossible, with 4-puck solid clutche etc.etc.etc... (you get the idea).

As for cylinder heads, Honda's have been known (at least the B-series in question) to have awesome flow charactoristics/volume/chamber design.

edit****

with that aside, you've got to understand you're dealing with 50+ year old technology with this pushrod v8's. Even the ford guys are now using overhead cams and variable valve timing. Although OHC engines are externally huge.

once you accept the technology, you'll find that ridiculous options are ALSO available with domestics (as with imports) like cams too large for practical street use, huge (300+cfm heads), and UBER high compression (like the import motors you're accustom to).

RC000E

Well, there are certainly some myths associated with what it takes to build Honda's in terms of cost. Costs are cheaper than any car out there though in my opinion. I could build a 400whp Integra GSR for 1500.00 no problem, and drive it everyday. Honda's have a ton of support, basically free full EMS's and have ridiculously capable motors from the factory.

Your description describes a top setup making 800-1100whp and is not typical of what's out there. My cousins car currently makes 890whp on 36psi and he has about 15,000.00 in it for reference. My car is built more for the street and makes mid 400's, has huge brakes, and custom suspension...I have 14.000.00 including the car. At 2300lbs it's a terror on the street and certainly capable of getting it done straight or in the turns. I love the cars, but the young group of core enthusiasts clearly have caused mixed feeling among middle aged or V8 enthusiasts.

Back on track though, while I love Honda's, they've provided me the window to return to my first love...the Vette. So, while I'll miss my pentroof chambers and variable valve lift, I have a lot to give the Vette world in terms of fab and build quality. What I bring to the table just wasn't appreciated in the Honda world so it's my hope to have some success here...we'll see.

Thanks for the info.

mnstrlt1

Very respectable power numbers, and even more so considering the displacement (PM me the details, block, internals, turbo used, etc). I think I would be hard pressed to find the average owner able to make the same power you've made with the few dollars that you've put into your build (retail pricing etc).

I've been out of the Honda game for some time, but you're certainly right, they are extremely cheap to modify. Huge aftermarket support, and a saturation of guys offering similar products (stiff competition).

I think I know what you mean as far as the honda community supporting the fab work that you do (i.e. they don't want to fork over the funds required for custom fab work).

The corvette community is certainly a little more inclined to pay the dollars for certain mods, but even the c4 is a bit long in the tooth. It's a dated platform and most "major" corvette oriented vendors have moved away from the c4 platform in the interest of the c5/c6. Which happen to offer the consumer a much more "tuner" friendly starting point. for instance, the fuel management can easily be programmed in real time with the flexabiltiy of the stock computer.

you'll find out that the stock computer on these c4's are pre-historic. For nearly any serious build on this forum, you'll see a stand-alone computer accompanying the build sheet.

For your intensions of boosting your ride (and I assume providing the community with a kit of sorts... since you mentioned a jig) will be a cool process to watch, but standalones (not MS) will run about $2K (accel DFI, FAST, BIG STUFF 3, etc). not to mention the proper fuel system to support any serious power.

I am definitely looking forward to seeing what you're capable of.


welcome to the community.

RC000E

Well, MegaSquirt would certainly be my app of choice. I've been building Megasquirts since VERY early in their availability when Honda management systems were still in their youth. I still have one unbuilt in my shop, so that'll be the one I use.

I've got some ideas and some things I've developed an interest in working on. Like I said, I want to do some N/A work and establish some familiarity with these, then I'll go from there. I've got some forced induction ideas as well...we'll see.

PM sent.

ScaryFast

It looks like you've made a decision, but I would add one more comment about the '92+ cars. The ignition system on the LT1 cars will be a nightmare for you to do the modifications you're planning.

The older cars are not much better as far as the computer is concerned, but it is a much more "traditional" SBC and therefore the options for aftermarket FI systems (such as the megasquirt, FAST, etc.) are far easier to implement on L98 cars.

The primary reason for this is the lack of a crank position sensor on the LT1 cars. Many people have adapted their optisparks to act as such, but it's a band-aid, and still prone to some of the common problems the optispark has in stock form.

My gut feel is that an LT1 car is a better ride in stock trim, but the L98 provides a much better platform upon which a tuner such as yourself can build.