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820vs840 kit

28K views 96 replies 26 participants last post by  PetesZ400 
#1 ·
Hi guys,
I'm having hunterworks build me a motor with the 820 fundy kit. My ? is what is the real difference in the 820 vs the 840, and how much hp does each have.
 
#2 ·
You should read some threads on these motors because you are about to open a big can of worms, I know both motors have alot more HP & torque than stock! I think you will still be happy with the 820 or 840.
 
#11 ·
My experience is very little gain from just cams without the high compression pistons to help with the flow, really just save your money and do it all at once.
I sure hope that this turns out to be a nice thread between all of our friends! :D
 
#12 ·
Why in the hell would anyone want to spend more money on an 820 vs. a more affordable 840? I don't care if the 820 is close in performance or not, the 840 is bigger and more bang for your buck. This infatuation some of you have with Fundy kits blows my mind. The way you defend using them over FST kits makes absolutely no sense. You have no argument whatsoever other than having to much money and no common sense.
I guess some people must have more money than brains, I don't. That is why I just purchased a standard bore kit from FST at almost half price of the Fundy kit. I'll be doing other mods with the money I saved and you choose to just throw away.
 
#18 ·
Best Post Ive read on here yet!!!
 
#21 ·
You didn't ask anything wrong,and you got your answer. There isn't that big a difference. I think what has people woundering why you wouldn't buy the better of the two when it's cheeper. You have to admit it sounds stupid if you use common sence.That's all I see that people are getting on you about.
 
#22 ·
It only gets heated when you made statements about something you never tested and you said thing that flat out were not true. STD bores do not make more power then 840's and 840's don't have any problems. Those two statements came from Fundy and you passed them off as fact. Now you were wrong in doing that and it blew up in your face because you tell everyone you test everything before you will sell it.

Now this blows up in you face too because you said you will sell someone a big bore kit but you will never instal one,remember that? You just need to watch what you say because when you get mad,or what ever happens to you when you get yourself in hot water like this you are going to have it come back on you. Now you have a customer that's not sure what to think because you say stuff and can't back it up with fact.

It's not a Ford vs Chevy thing.Ray builds good stuff,but he tells storys and it gets him in hot water too.
 
#19 ·
I agree FST 840 is a better deal.
 
#20 ·
Dont the 840 have thinner cylinder walls? Is that not a problem and does one of them tend to run hotter than the other. Not trying to start any shirt but just wanting to hear alls opionion since i am try to make up my mind on standard bore, 820 or 840 kit.
 
#24 ·
I think it is almost time for Popcorn, sit back and enjoy the show!!! :D:laugh::wave:
 
#28 ·
Well at risk of fanning the flames, I'll make some comments...

1) If Fundy is lowering their prices, I suspect that they want to hedge off the competition (FST) some. Companies don't give away margin unless the market place dictates it. This suggest that while I'm sure that the Fundy is a good kit, so is FST or they would simply be able to maintain their margins/price and convince the customer that they were technically superior. Aparently, they haven't made that case successfully. I don't know this, but its what I read into the statement.

2) Hunterworks has suggested multiple times that there is more to his support of Fundy vs FST ("We do what we do for a reason and I won't air too much here it is not the right thing to do") by hinting tha there is more to it than we know. Well, if that's the case, it's BS to go online & knock a product without telling the forums 'why' so that we can make a judgement on our own. For instance, I've had issues with an HW product in recent times, but this isn't the place to get into that.... Aparently HW prefers Fundy kits and that's fine. I only ask that you tell us why if you are going to question a competitors product.

These are just what I read from the post and I stand to be corrected. I'm sure that Fundy, HW & FST are all passionate vendors with good products who all occassionally make statements that are misunderstood or that they would like to take back. In any case, there seem to be a lot of 840s out there and those of us who've been online for a long while haven't heard any major issues with either kit. I suspect that the major differences are reputation, customer service & price. I like that all of these guys are passionate about their work in supporting what we enjoy...

Ride on.

Some people rub people the wrong way, some want the most expensive some the cheapest... Bottom line, I'm reasonably comfortable with all 3 vendors.
 
#29 ·
By the way... forgot to answer the original question ;)

I would think that bigger is better to a point. It would go for the 840 over the 820 just $ for $, but I doubt that there is much difference in power for the 20cc. Bigger is better though. To a point, and I haven't read about any 840 issues. This motor has been around & modified for a long while. There is history out there. I don't know all of it by any means, but some research should prove it out.
 
#30 ·
Crash,

The reason Fundy kits are coming down in price is the supplier is changing.

Fundy uses JE pistons not the lesser expensive Wiseco, they use the same cams as most everyone else Web cams so that is the same price except they have to cross the Canadian border twice which makes the price shoot up and they use a more expensive valve spring with moly retainers instead of a cheaper spring with no retainer that may or may not fit the stock retainer very well. They use the same gaskets too. The piston shape and cam profiles are custom for each company.

They now have a company in Europe that makes most of the Formula One engine parts making these parts and they are buying about 3000 parts at once so the price is dropping down and the quality especially on the cams is going up. A spray welded cam like Web's pits sometimes.

They also don't bore and plate the stock cylinders for there 820 kits they resleeve them which cost more but is better after going thru heat cycles.

They stopped doing 840 kits according to Ray because the other kits they had out did them and regardless what anyone says cause the cylinders warped according to Ray.

I still won't air everything I know or think I know about others, it is just not right.

I buy who I am comfortable with, who has top shelf stuff and who supports me like I support my customers and Fundy is that company.

If you have a dealer network you totally support then the retail price has to be higher than someone who makes the kits and sells them direct.

If the person who has a dealer network and then sells to the public at dealer cost even on a sale just screwed the people who support him.

It is not always about the product but in Fundy's case it is the product and the support.

The rest of my reasons I won't mention ever on a public forum.

If you had issues with one of our products you should call me and I will make it right!!
 
#31 ·
Good info HW. I still think that most companies don't give up margin unless they have too. That's not always true, but it is something that folks think about. The value is what you can sell it for and the quantity. Cost is generally only one part of the equation.

I appreciate the info regarding where Fundy is heading. I'm not sure that I'm qualified to say that JE pistons are better, as I raced with Wiseco pistons for many years. I also raced other brands including OEM and they all held up. That was many moons ago though!

I'm not willing to say one is better than the other because I personally don't know. I do appreciate your perspective better when it's set up as a technical comparision until there is good honest comparitive results. Just remember that when Fundy/ or HW question the mechanical integrity of an FST kit, there are lot of guys out there running it success. Suggesting that their kits are flawed in some way will get taken personally. I would want to be certain that there is some proof to that end that can be referred too.

No worries on your products. I made the statement to make a point... in my case, it was no big deal and I'm cool. I sent you a PM just because I think it's constructive feed back that I would appreciate.
 
#33 ·
To me this whole line of talk is about as constructive as why I drive a Chevy Duramax and will not drive a Ford cause I think they inferior in quality.

There is so much evidence that Ford is a good product but I just can't drive one cause of what happened to my dad on a 1979 Ford truck that was total junk.

I have no proof of anything I just like Chevy's and don't feel like I need to explain it cause my mind is set!!
 
#34 ·
So I can understand better just how many STD,800,820 and 840 kits
have you built ,engineered or modifyed Todd??? You keep speeking as
engine builder expert but I have searched all over the web and all I can
find is that you rebuilt your rhino engine and as I think I read it correctly
it didnt last long.....FST has been arround a long while and before I
purchased an engine kit from him I researched him and his business
and I found that the majority of the people that delt with him agreed
about very good service and thats what I got from him allso as far
as piston quality, Wiseco pistons have been an aftermarket piston
in the motorcycle/atv world for decades. Todd and for customer
service think VDI and our 45 min conversation on how it wasnt
your fault and not making that much yadayadayadablabla and I
dont think you even offer them anymore when you said they
were the best thing since sliced bread.
 
#35 ·
See this is why this goes no where.

My rhino is running fine, just got thru winning a 8hr endurance race with it against RZR's and Teryx's

When you cover the radiator up with mud and keep running it it will destroy it and when you put a 100% load on it on a dyno a bunch and then run out of gas during the test cause your stupid it will destroy it.

After both builds and under normal riding it is great!!

I never said I was the expert quiet the contrary I leave that to the experts like Ray and Mickey.

FYI I sell and use Wiseco for the Rhino just not on the Teryx cause we use Fundy and they use JE. If Ray thought the Wiseco was fine I would be running it in the Teryx too.

I just said I like Fundy and use them for my own reasons.

When you become liable for products and are in the line of fire for problems you want something that you are confident in and have a good line of communication with the designer or actual kit maker.

I have no real proof of anything negative on Mickeys kits same as the Ford truck in the example.

I'm done with this thread and won't comment again on any thread questions which is better I have learned my lesson.



I know there is lots of kits of FST out there running strong I just don't want to sell his stuff.

Todd
 
#36 ·
the biggest difference in my opinion..is price.i wouldnt image that 20 thousands would matter much in power department like the 820 and 840?but when you can go 840 for less it really seems like its a no brainer.but then again i cant really tell you about either kits or companys to make you lean one way or the other..but recently i ordered the 840 from mickey from fst and still waiting for it to come.but as far as research goes..i have followed the debate about fst and fundys for a few years now on who is better.and i guess it really boils down to who you decide you want to buy from.fst has sold more 840s than any other company and i have never heard anyone badmouth one of his kits ..so that is enough for me and plus its cheaper too.i know that fundy claims to have better parts in his kit and thats why the kit is higher..je pistons vs wiseco?i wonder how many 840 kits has had to change their pistons out to je due to being not worthy for the motor?i know ray has always leaned towards the standard bore kits because of the stock carbs couldnt provide sufficient fuel for that big of cc engine.and even sold an 840 and now sells an 820..go figure?but anyways...im sure which ever one you decide to go with you will be happy.
 
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