I haven't heard of any larger deinonychus discovered, but then there's so much to keep track of, I'm finding more is slipping passed me than used to. So I admit I may be wrong. However, I believe you may be referring to the discovery of Utahraptor which was discovered about the timeframe you're referring to, and slightly larger than the raptors in the film.
Also Utahraptor probably has about the fastest turnaround from it's announcement to toy ever, as Kenner put one in their JP line almost immidiately.

As for grimlock, funnily I just had a conversation about him. When his toy was originally designed as a diaclone, they were already overturning almost all the old concepts about dinosaurs. By the time the Transformers came out, the old portrayals only lived in pop culture. And that's where there was a big war over dinosaurs. The new concepts (Which paleontologists were actually aware of right from the start) were not popular. Pop culture didn't want to embrace them, schoolbooks didn't want to embrace them, and some paleontologists didn't, either (I used to get cs, ds, and fs in the eighties on my reports in school because I was constantly pointing out the schoolbooks were wrong). That, combined with the general ignorance of most cartoon writers and toy designers... well, the eighties were full of 50s stereotypes.
It's why I love Dino-Riders so much. Everything about them took dinosaurs seriously (The only reason the Rex is dragging it's tail is exclusively for stability of the toy. Kentrosaurus and Deinonychus held their tails high)

On a side note, Grimmy's toy almost makes me wonder if his designers were aware of the newer theories, as his tail is almost straight, and it can take an anatomically correct stance and look good doing it. (Something that does not work for his godaweful MP dinosaur mode. That thing makes me ill)

Sorry Sectaurs-but you dont stand a chance!

The Utahraptor discovery was a separate incident (but still lent some credence to JP's design choices after the fact). I'm paraphrasing here, but Stan Winston (effects creator for JP and many, many other films) was asked about the Deinonychus discovery and said basically "We made it up and science made it real."

And personally, I've never had any real big complaints with Jurassic Park's portrayal of dinosaurs, mostly because I always assumed it was because they were mutants (frog DNA and whatnot).

I've often wondered that too. Maybe the designers were aware of the debates going on in the scientific community at the time and decided to hedge their bets, as it were.

As for MP Grimmy, his dino mode was based solely on the cartoon's portrayal, so that's why he looks like the long-lost little brother of Mechagodzilla.

I never had much issues with the movies. Dispite innacuracies, I love them. And they were a lot of peoples first excposure to what dinosaurs could really be like.

Yeah, I understand exactly why MP Grimlock has his godzilla-mode. Doesn't mean I like it though.
Takara's obcession over a very bad 80s cartoon is one of the reasons I've come to hate the sunbow cartoon as much as I do.

Dino Riders, you say?

http://farm8.staticflickr.com/7084/7...98ba8402_b.jpg

Oh..
I voted Dino Riders, though I still would even I had heard of Sectaurs.

Because, come on. Riding dinosaurs bristling with artillery. The concept is incredible, it's difficult for any logical person to dispute that. There are things that supersede personal taste and are awesome beyond refute. Dino Riders is one such thing.