port and polishing a 800 ZX H.O

[chopshop]

I was wondering if anyone has port and polished an 800 ZX H.O. Roughly how many horse can I expect to gain from this mod, Is it worth the time and money? I have done it to a YFZ450 and was quite impressed. I dealt with tom at MOTTS machining in St.Albert, and he was a stand up guy with good service.Thanks for your help :d
Nate

 

[maxwell]

it isnt huge gains. maybe 5hp i would guess. but the rk or shr bb kits with head new pistons larger displacement the combination really rips. 20-30hp

 

[RT Ryder]

I have been thinking of doing this to my 04 YFZ 450 but was curious of the gain. Would you say it made more of a difference than a pipe?? could you PM me with the price you paid??

 

[Pappillion]

Personally, I found it to be a waste. I didn't notice any difference until I put on a high compression dome, v-force reeds, pipe and can. Together with all the mods I felt it was worth it but on its own I wouldn't recommend it. Not worth the time and money. jmo.

You may want to consider clutching or even playing with your gear ratio. These are much cheaper options and you will definately notice an improvement.

 

[Canuk]

I talked to Tom at Motts and considering it's already an HO you will gain little from more porting, Tom indicated polishing wont produce big gains either. He suggested you I would be lucky to get 5hp. Seemed to me my $600 is much better spent on a head or BB. Maybe a drop-in kit?

 

[magnet]

or add abit more dough and all you need is tyree little letters nos:djust sayin.

 

[maxwell]

or add abit more dough and all you need is tyree little letters nos:djust sayin.

i fully support this statement

ha

 

[Terra Alps Racing inc.]

proper porting will make good gains, its worth it on the 800 HO, we also build custom y pipes for our 830HO and 800 HO performance kits.
Add dual ring cast pistons and a billit head and the performance is good.

 

[DRD]

proper porting will make good gains, its worth it on the 800 HO, we also build custom y pipes for our 830HO and 800 HO performance kits.
Add dual ring cast pistons and a billit head and the performance is good.

What are "good gains".

 

[Deano670]

What mods have you currently done on the machine or is it stock??

 

[Terra Alps Racing inc.]

What are "good gains".

Consider your making 130-135 hp on a stk used zx800, get a real port job, install a good head, good set of pistons and make up to 160 on pump gas. Some race motors will make over 170 but rev high. not for mtn use.

I would say these are good gains.

 

[the devils reject]

i was wondering if anyone has port and polished an 800 zx h.o. Roughly how many horse can i expect to gain from this mod, is it worth the time and money? I have done it to a yfz450 and was quite impressed. I dealt with tom at motts machining in st.albert, and he was a stand up guy with good service.thanks for your help :d
nate

call ted at terra alps. I installed his head on my xp. Worked awesome. Well worth the money. Imo

 

[Deano670]

Just my opinion, i would spend the money on a set of crankshop twins, v force reeds and some good clutching. Considering its an ho already. Will porting make SOME more power yes indeed it will. But i think you will find larger gains in pipes and reeds than porting. Money better spent. However if you spend the money in pipes and reeds aswell as porting and heads well all in all its a package deal. How much do you want to spend? How much are you looking to gain for what your willing to spend? I will say this, i have seen first hand Teds porting on an 1160 big bore cat and the difference it made, It worked and it worked well.

Deano

MAD MOTORSPORTS

 

[Terra Alps Racing inc.]

Thanks deano, yes with some real porting all motors will work good and better, I ported quite a few of the 1150 big bores and they work much better. changing the shapes of ports as well not just raising a port height to try and get more top end power, but gain more air flow which gains more hp thru out the whole power band. The 800 skidoos even the HO motors need porting they are restricted and the gains are very good. The 800r motors are ported alot more then the 800 ho's stk. and we have a porting package for the 800r's as well, that we have been doing on our 860 bigbore kits. When we bolt on our 860 kits and drop the primary spring rate from a 320 to a 260 and add a few grams of pin weight and its on clicker 1-2 and still over revving that is impressive. that says its making some power.
I find the stock pipes of skidoo work well, for the average rider in the mtns I perfer to set them up with a stock pipe over a twin set, no need to repack teh glasspacks every year. and not so noisy, man sounds like I'm getting old!

 

[team dirt]

Ted did an awsome job on my 04 800ho. Flat out rips now even with my fat as$ on it. I highly recomend terra alps. I am getting one of his chassis this summer.