Need help with engine mods

[Wildrebel]

i just purchased the predator 212 hemi 60363 and installed performance header pipe, after market filter, 18 ib springs, rejected carb and replaced e tube with a 140 and also bypassed the gov it is an obvious improvement in performance but im continuously floating the valves between 5300- 5500 rpm but have never exceeded 6k, my freind bought a new predator as well except he has the non hemi and has only upgraded the header and bypassed the gov still running every thing else stock and his valves dont float until a good 6k. i want to make mine run circles around his but dont wont to spend a whole lot on performance parts so i was gonna try to use the other engines i have to make my hemi out perform my freinds the engines i have is the old style predator 69730, harbor freight 6.5 196cc model 96549, and a honda gx160 clone off of a red lion water pump. what could i use off of these to make one?

 

[Whitetrashrocker]

What kind of karts are you comparing? Tire size, gearing, weight?
Too many variables.

Post pics for these guys.

 

[Wildrebel]

out of those varibles which of them will help assist with engine mods. the advice im seeking is how can i upgrade my hemi with parts from my other engines instead of spending alot of money on performance parts. as an example i know a guy who raced karts before ohv engines and they would run smaller diameter flywheels from other engines and different heads, twisting cranks without having to buy all the performance parts,like putting a gx160 14cc head on a gx200.

 

[Whitetrashrocker]

Ahh young grasshopper.

I could take a stock, governed engine and make it smoke a "built one".

Again gearing, weight , tire size.......

---------- Post added at 08:40 AM ---------- Previous post was at 08:39 AM ----------

How do you know Rpm's. Do you have a tach on them?

 

[bob58o]

Tell us the what kind of karts and also the gear ratio and tire size on each kart, then....
Get a billet connecting rod.
Put the 160cc head on the 212cc engine.
Since the head is off, buy a new thinner gasket.
Shim the springs to get more seat pressure???????? (Not sure if this will work, is this a reason why one would shim valve springs?)
Make sure you are geared correctly.
Get a rear view mirror.

---------- Post added at 10:12 AM ---------- Previous post was at 10:08 AM ----------

Ahh young grasshopper.

I could take a stock, governed engine and make it smoke a "built one".

Care to put your money where your mouth is?
JK I get what you're saying.

 

[Whitetrashrocker]

Care to put your money where your mouth is?
JK I get what you're saying.

Sure! Come to the drag strip.
Last time we were in El Paso I was watching 2 stock street legal Hellcats just whoopin up on the other door cars.

 

[Wildrebel]

i assure you i understand gearing and rations i do that type of work for a living, and yes your right for the most part about smoking a built one with a governed one all with tire size gearing and weight, but back to my question with the hemi i just bought ive seen some forums that said something about taking those engines i have and making one but it didnt go into details

 

[Whitetrashrocker]

Then follow Bob's advise. Billet rod, thin head gasket, perhaps an offset timing key, stiffer springs. (Yea bob shims make the spring feel stronger but at the cost of travel).
More fuel more compression more spark more hp.

 

[bob58o]

Sure! Come to the drag strip.
Last time we were in El Paso I was watching 2 stock street legal Hellcats just whoopin up on the other door cars.

Assuming the modified engine was built for the specific race and the vehicle was geared for the distance of the race,... A governed stock Predator WILL NOT smoke a modified one. Assuming chassis are similar.

https://www.youtube.com/watch?v=LQCU36pkH7c
Kidding, just been wanting to post this. Sorry. LOL

---------- Post added at 11:31 AM ---------- Previous post was at 11:28 AM ----------

Then follow Bob's advise. Billet rod, thin head gasket, perhaps an offset timing key, stiffer springs. (Yea bob shims make the spring feel stronger but at the cost of travel).
More fuel more compression more spark more hp.

Oh ya, offset timing key.

 

[OzFab]

i assure you i understand gearing and rations i do that type of work for a living...

Regardless of whether you know exactly what you're doing when it comes to gearing, WE DON'T know what you're doing; knowing all the variables will help us advise you the best we can...

I was in the auto & metal fabrication industries for over 25 years but, I still joined here for help & guidance...

 

[Flyinhillbilly]

.009 head gasket
GX 160 head with some port work & 18lb springs.
8 degree timing key
22mm mikuni

I'm getting geared up to do a video on how to set your timing without a key. I found the easy button.