Predator and XR2500 head swap?

[juniorssrollin]

I have a Bandit chassis kart that me and quite a few other people all run a clay oval with. Everyone runs the Harbor freight 212cc. I although want a little bit more power with keeping it looking "stock".
I have a Honda Xr2500 that seems to be a strong motor, was curious if the head will swap to boost compression a tad. Already have the 140 E-tube and #35 jet in the predator. Any other mods that will appear stock?

 

[firemanjim]

Milling the stock head, boosts compression = +hp
Advance timing = +hp
Tweaking governor to get a few more rpms= +hp

 

[OzFab]

I like the way you think but, unfortunately, I don't think you can swap the heads; what you can do (apart from what Jim mentioned) is use a 14cc GX160 head (confirmation needed but, I'm pretty sure it's been done...)

 

[Half-breeder]

I like the way you think but, unfortunately, I don't think you can swap the heads; what you can do (apart from what Jim mentioned) is use a 14cc GX160 head (confirmation needed but, I'm pretty sure it's been done...)

(From what I hear/read)Yes, a GX160 head(old style 14cc stock), is an awesome addon/bolton for greater compression(aswell as the thinner gasket)! The compression ratio of a HF212 is 8.5:1... w/ the head and thinner gasket I think I read, itll be around 10.5:1. A flattop piston adds extra compression aswell as milling the head/block.

 

[anderkart]

Honda doesnt make a XR2500 engine, thats the model# of your pressure washer. Your engine is the Honda GC160 model, its an overhead cam engine that's a completely different design than a predator.

You'll find lots of predator performance info at these 2 links:
http://karting.4cycle.com/forumdisplay.php?73-Predator
https://www.google.com/search?q=hon...r=1#q=stock+appearing+predator+engine&spell=1

 

[Russ2251]

Good catch on Anderkarts part.

It should be pointed out that head is not removable on the GC series engines.
I use mine as a beater engine.

 

[firemanjim]

Good catch on Anderkarts part.

It should be pointed out that head is not removable on the GC series engines.
I use mine as a beater engine.

WHAT do you mean a beater? On a beater kart? Just to thrash-n-trash it? I had one of those..... Had being the emphasized....... It finally popped/pooped..... Good time,good times......

 

[OzFab]

Good catch on Anderkarts part.

I caught it, I just didn't say anything...

It should be pointed out that head is not removable on the GC series engines.

How is that possible? How would you remove the piston in the case of a rebuild?

 

[Russ2251]

How is that possible? How would you remove the piston in the case of a rebuild?

How did Russ2251 do it? Anyone?

 

[rmm727]

A GC160 or 190 is split diagonally across the the centerline of the crank. One crank journal is on one part of the block, the other journal is on the other. Very interesting how they come apart.

I have a GC190 (former pressure washer motor) on a DB30. I love that thing. Good pulling motor in stock form.

 

[Russ2251]

Very interesting how they come apart.

I also found a less messy way of re-assembly.

 

[juniorssrollin]

Awesome info guys! I was being hopeful for a free mod. I've looked around for the thinner head gasket and seems they are sold out everywhere. TS racing is close to me so I'll take a trip over there. I'll have to get video uploaded but these karts are a BLAST! I'm looking for another chassis to build my girl one.

 

[juniorssrollin]

Also what degree timing key would be safe to run?

 

[OzFab]

How did Russ2251 do it? Anyone?

A GC160 or 190 is split diagonally across the the centerline of the crank. One crank journal is on one part of the block, the other journal is on the other. Very interesting how they come apart.

I have a GC190 (former pressure washer motor) on a DB30. I love that thing. Good pulling motor in stock form.

That is interesting but, I still don't get how you would work on the head, I can't quite picture it, I'll have to look into it...

 

[zbuck]

GC190, the head and block are cast as one piece. Therefore no head work. It makes me wonder about the valve seats? Looks to me that you have to dis-assemble the whole engine to get to the valves. With the block and head being one piece, I am guessing that you remove and install the piston, from the bottom side of the bore.

 

[ML-TOYS]

I am curious as to wether you have rules that you are to follow for the engine since you
say stuff like
"with keeping it looking "stock" "
"Any other mods that will appear stock?"

 

[Moedog07]

What have y'all agreed on as "Stock"?
Stock appearing? Stock externals?

If stock appearing is the rule the cut open the botitle neck of a muffler and gut it out. Those things can't flow well.

 

[Russ2251]

That is interesting but, I still don't get how you would work on the head, I can't quite picture it, I'll have to look into it...

Can you wrap your head around the fact that it only has 1 cam lobe?

 

[Scout]

I like the way you think but, unfortunately, I don't think you can swap the heads; what you can do (apart from what Jim mentioned) is use a 14cc GX160 head (confirmation needed but, I'm pretty sure it's been done...)

You can buy new gx160 heads online. That and a cam will be my next mods.

 

[OzFab]

Can you wrap your head around the fact that it only has 1 cam lobe?