Interesting II...(Sorry Paul)

[flyin ryan]

I'm just a little blown away at how popular these are in the performance world? You can't convince me our LT-5's wouldn't walk all over these Mod Motor's given equal development time from the aftermarket world. LT-5's valvetrain (or lack of!) is so simple, clean & well thought out crazy going to work on a Mod Motor, I think. Intake ports on the Mod Motor are decent but the Exhaust ports are no screaming hell. The fact you have some choices of Intakes is of coarse nice though. Just thought I'd share my thought's......

[mike100]

Originally Posted by flyin ryan

I'm just a little blown away at how popular these are in the performance world? You can't convince me our LT-5's wouldn't walk all over these Mod Motor's given equal development time from the aftermarket world. LT-5's valvetrain (or lack of!) is so simple, clean & well thought out crazy going to work on a Mod Motor, I think. Intake ports on the Mod Motor are decent but the Exhaust ports are no screaming hell. The fact you have some choices of Intakes is of coarse nice though. Just thought I'd share my thought's......

Maybe GM will re-embrace the DOHC V8 at some point and build it based on the experience from the LT5 and Northstars. Then you would have a proper, ideologically correct, transplant. problem is that that was so long ago, and GM probably has had so much turn over that the new engineers probably have to keep relearning from the same mistakes the old engineers already made.

[Paul Workman]

Originally Posted by flyin ryan

...You can't convince me our LT-5's wouldn't walk all over these Mod Motor's given equal development time from the aftermarket world. .

I agree - far as what could have been accomplished by now if the LT5 received the same development effort/resources since inception. I mean, a fully ported, 350 cid LT5 with headers and a free flowing exhaust and stock cams makes over 500 at the crank, yet idles smooth and gets 24-26 mpg in 6th/cruise at 70 mph...

For a block even just an inch longer, and considering GM had the opportunity to widen the gap between the frame rails an inch or so with the C5/6 platform...what monsters would there have been coming out of Bowling Green by now? Or, even keeping the 5.7L dimensions, and adding VVT and direct injection... I hate having to look to Dearborn (Ford plant) to see what might have been, if you know what I mean.

Just making noise...

P.

[tomtom72]

I often think about the same thing, what if there was a second LT5. At the 20th last yr they said they had done one specifically for the C5-6 chassis. Ours are too tall for the hood line of a C5.

This was a presentation given at the BBQ over at JVD's. There were a number of new LT5's made, 50 I think. It had VVT, relocated single injectors, OBDII management, no gas guzzler tax, redesigned combustion chambers, new I/H's & Plenum & T/B, MAF combined with MAP ( I'm not too sure as I don't speak EEC very well ), and wait for it, wait for it.....the opening bid on the new LT5 corvette base motor was to yield 450 hp @ 5.7L for the 97 C5.

I think if you want to see what the combustion chamber redesign would have looked like, or something similar to the thinking, look up Todd's 427 thread.

This presentation was given by Graham and Dave. They also had plans for somewhat larger displacement motors for the ZO6 & ZR-1.

It makes me sad to think that I could have bought a used base C5 coupe with a 450 hp DOHC motor someday if things were a bit different at CPC back in 91.

Tom

[flyin ryan]

& another thing! lol....These Mod Motors primary cam gear's that drive the cams are off the Exhaust cam...that makes no sense to me. To degree the cams need to start off the intake, makes it hard given movement, slop etc. when your starting everything at the exhaust...no matter how many tensioners are in the system. It was actually a good experiance for me doing this engine in the fact it heightened my appreciation, which was already quite high, for the original LT-5 design in it's era.

[DaveK]

I remember that presentation too Tom. I would love to have seen a further generation of the LT5 too. If I recall from the HOTB they had full working engineering prototypes for the 450 motor and also blueprints for a further iteration that would deliver 500+

Damn those GM bean counters for killing the development.

[tomtom72]

Okay, so I'm not dreaming! You know if you listen and watch closely when Dave, and even Jingles talk you begin to pick up things.

This year both of them participated in a Q&A seminar given by Marc about the unique qualities of the LT5. Dave & Jingles started to chew the fat over how to beat the emissions testing with an LT5. It was great stuff.

However, if you were at the JVD 20th BBQ and here at the NCM for the seminar this year I began to piece things that those guys said into a sequence. Dave's own words..." we poked too many sticks in too many eyes.."
The "with the LT5" was left unsaid, hanging in the air at the end of many thoughts that they both verbalized.

Sorry, rant over!

Tom

[VetteMed]

I think that a big part of the death of the LT5 had something to do with hurt feelings among the die-hards at GM who hated the idea of anything other than a genuine SBC powering a Corvette. Sure, the beancounters kill anything fun -- GN/GNX, Impala SS, the last Fiero, but as mentioned above, I bet the roots reaching across the ocean to England, made those sticks in the eye extra sharp.

[Kevin]

Originally Posted by mike100

I never liked the modular 2v engines...they would blow a head gasket at 100 and some odd thousand miles and usually you just junked the car.

having 98k on mine, i hate hearing this

[mike100]

Originally Posted by Kevin

having 98k on mine, i hate hearing this

Just stay vigilant with your cooling system. They are some kind of multilayer shim gaskets which required a mirror finish on the heads...I think the aftermarket ones work with a traditional finish, but the labor involved for a top end job on a 4.6 or 5.4 is kind of high for a car with 150k miles on it.

lots of complexity for 200 hp.