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more HP wanted

ruffryder said:
BooBoo said:
You can do some head work and gain another 10-15hp on top of what you are doing.
Click to expand...
hmm.... I thought it was 10-15 hp for head work while you are boosted. I haven't heard big gains like that from a little port work, as that seem like more then an exhaust and header w/ commander combined.
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This is what they told me at hurricane. They asked if i had header and intake mods first and then stated that yamaha left alot on the table as far as porting goes and that I could gain 10-15hp. Boost was never brought up, he just ask what mods i had and recommended that i had header and intake mods done first.
 

The only thing I dont want to do is jump into race gas, I would not mind puting premium in the machine and if I could keep it on regular that would be even better.... 10-15 hp extra would be killer
 
When I spoke to Dave last fall about head porting he said that running 87 would still be possible...as long as you are still running stock compression...once you bump that up you need to start running better fuel...but with a "port only" job you should be fine on 87.
 
so how much do you think i can shave off the head and still have the engine be yamaha strong? 10-15 thou?
 
NOS is not a very good solution in my opinion. You can't just press the nos button all day and cruise around with an extra 20 horsepower. You'll run out of juice. Would be good for the occasional drag race but thats where my interest in NOS ends.

I'd look into the head porting from Hurricane. And if you want a little more, ask him about shaving a little off the head, so you can get a little extra with Premium fuel.
 
That is what I am looking at doin, i have the porting abillity here at out shop and have another shop that will shave the head for me..... just have to think about how much to take off :o| I think i will start at 15 thou and maybe jump up to 20 thou
 
yukon yamaha said:
That is what I am looking at doin, i have the porting abillity here at out shop and have another shop that will shave the head for me..... just have to think about how much to take off :o| I think i will start at 15 thou and maybe jump up to 20 thou
Click to expand...

Do you have a Dyno available? I know a lot of guys would be interested in how much horsepower the porting and head shaving will actually free up.
 
NO I live to far up north, there is really nothing up here for dynos and to ship the motor or sled out would be double $$ of the porting and shaving... But I would also like to know what the gains would be!!
 
I took 25 thou off and did a mild porting. I didn't dyne but I know on a top end pull he keeps her speed and rpm.... Before on a wet sticky snow ride I couldn't get over 85mph with a 20 top gear. Same conditions with same gearing and I'm seeing a constant 94-95 mph and I've even seen 98 on nice snow with that gearing.. Never had a chance to try with the stock 21 tho.
 
yes! That is great!
I dont think that will only shave off 15 thou and do alot of porting and polishing
 
Just remember that a head gasket and head bolts must be replaced.. I live in Canada but I bought my parts in the US and it ran me $100 just for those parts. No idea what it would cost in Canada.
 
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