New Polaris Turbo Heads

700RMKBOY · Dec 9, 2009

Eightysixd Industreis has released its new 9:1 compression heads. These heads give that huge top end power your looking for with a minium loss on the bottom end. These also alow you to run higher boost levels on lower octane gas.

For more info call
406-539-3015

gtfoxy · Dec 9, 2009

If they work so well, then why do they need to produce a drop in static compression ratio?

KAWGRN · Dec 9, 2009

+++++1

snow_knight · Dec 9, 2009

Derek.. please post up MORE info on these..

JesseJames · Dec 9, 2009

gtfoxy said:
If they work so well, then why do they need to produce a drop in static compression ratio?

The lower compression allows for more fuel and air to be crammed into the cylinder to produce more power, on the same octane fuel.

Nelson · Dec 20, 2009

Precisely, It allows more room for your boosted charge, which is why you can run higher boost on lower octane.

snow-seeker · Dec 21, 2009

Are these for the 800 or 700?

supraturbo · Dec 21, 2009

700RMKBOY said:
Eightysixd Industreis has released its new 9:1 compression heads. These heads give that huge top end power your looking for with a minium loss on the bottom end. These also alow you to run higher boost levels on lower octane gas.

For more info call
406-539-3015

how is it possible to lower compression and gain hp at same boost?? if possible please explane all of us.

Boyko · Dec 21, 2009

supraturbo said:
how is it possible to lower compression and gain hp at same boost?? if possible please explane all of us.

A better head design with changes to the squish band and dome configuration will do it. Sounds crazy but it is possible if the areas have not been optimized already. I think Dereks point was getting more power by running a littel more boost with the same fuel.

maxrev3 · Dec 21, 2009

When you lower the static compression it allows you to use a lower octane fuel which is more prone to pre ignition or detonation at higher compression ratios Yes you loose thermal efficiency but you can run more boost pressure and fuel to compensate for the loss
With more boost and fuel added you gain Hp
there is more chance for detonation on a high say 11.0 static compression running 50/50 mix of race fuel and pump gas @ 14lbs of boost than the same motor running 9.0 comp @ 18+ lbs you will have approx the same Hp numbers on top but a little less on the bottom due to the static compression loss.
When you run higher boost the motor will tolerate a richer air fuel mixture due to the higher volume of the air charge
which will keep the combustion chamber cooler and decrease the chance of detonation meaning a larger margin for error can be seen with out damage to the engine hence a safer longer life high horsepower engine running pump gas
If you still choose to run a 50/50 mix you can run even more pressure to make higher HP numbers more reliably.
I hope this helps in understanding the issue of static comp on a forced induction motor
and for all the guru's out there If I have missed something here please let me know
Thanks

supraturbo · Dec 21, 2009

maxrev3 said:
When you lower the static compression it allows you to use a lower octane fuel which is more prone to pre ignition or detonation at higher compression ratios Yes you loose thermal efficiency but you can run more boost pressure and fuel to compensate for the loss
With more boost and fuel added you gain Hp
there is more chance for detonation on a high say 11.0 static compression running 50/50 mix of race fuel and pump gas @ 14lbs of boost than the same motor running 9.0 comp @ 18+ lbs you will have approx the same Hp numbers on top but a little less on the bottom due to the static compression loss.
When you run higher boost the motor will tolerate a richer air fuel mixture due to the higher volume of the air charge
which will keep the combustion chamber cooler and decrease the chance of detonation meaning a larger margin for error can be seen with out damage to the engine hence a safer longer life high horsepower engine running pump gas
If you still choose to run a 50/50 mix you can run even more pressure to make higher HP numbers more reliably.
I hope this helps in understanding the issue of static comp on a forced induction motor
and for all the guru's out there If I have missed something here please let me know
Thanks

you answered my question......it is not possible to gain any hp by lowering compression........!!!! you need more boost to make hp......so it is not fair to advertise heads with lower compression that will make more power at the same boost just mu .02

Spaarky · Dec 21, 2009

These also alow you to run higher boost levels on lower octane gas.

Doesnt seem like false advertising to me... no where did he say you gain HP running the same boost...

Boyko · Dec 21, 2009

Outlaw Addict said:
Doesnt seem like false advertising to me... no where did he say you gain HP running the same boost...

Ya what he said, and on the other side of the debate.. I could build you a low compression head that would detonate so fast at low boost it would make your head spin ,

lol

supraturbo · Dec 22, 2009

Boyko said:
Ya what he said, and on the other side of the debate.. I could build you a low compression head that would detonate so fast at low boost it would make your head spin ,

lol

what do you mean by``would detonate so fast`` low compression is to avoid detonation with low octan fuel........

Boston Racing · Dec 22, 2009

I am sure it is possible to lower static compression ratio and not lose power, just from a better head design. Its really all a [ackage though. I have a Superflow Dyno and have done lots of testing on Banshees and other 2 strokes and we see it alot, more compression is not always better. Even on normally aspirated motors

I also think was the previous guy was getting at was a bad dome design would be prone to detonate even if the static compression was low

Boyko · Dec 22, 2009

supraturbo said:
what do you mean by``would detonate so fast`` low compression is to avoid detonation with low octan fuel........

A wide squish band with .028 clearance to the piston dome will give you a trouble on a turboed two stroke.

There has been a lot of time spent on different squish bands and dome shapes to get a few more hp out of a stock 2-smokers some have a little less compression. The same can be done to a turboed engine

zrt1 · Jan 1, 2010

so bye running these lower comp. heads, what happens to the low end? In my experiance (wich isnt that much) it turns it into a total pig untill your on boost? am i right or no?

Spaarky · Jan 3, 2010

ZRT ...... that was my exact thoughts when I saw the 9:1 heads. It depends on the fuel you are running, but a lot of these pump gassers are running stock comp or real near it.

Search

New Polaris Turbo Heads

700RMKBOY

Free Member

gtfoxy

Member

KAWGRN

Well-known member

snow_knight

Well-known member

JesseJames

Active member

Nelson

Well-known member

snow-seeker

Well-known member

supraturbo

Banned

Boyko

Well-known member

maxrev3

Free Member

supraturbo

Banned

Spaarky

Well-known member

Boyko

Well-known member

supraturbo

Banned

Boston Racing

Well-known member

Boyko

Well-known member

zrt1

Free Member

Spaarky

Well-known member

Similar threads