Performance Upgrades?????

[raptor ridin bubba]

Ok so I have my plastics in the shop being painted, then I'm going to put the kat back together and ride it through the rest of the season. Once winter gets here if history repeats itself I will be tearing down the Katana due to a serious case of upgrade-idise. I'm not sure what wrong with me, but it doesn’t matter if it a car, a bike, or and ATV, I gotta have the go fast parts!!

I have a few questions about which upgrades the 1100 will respond to the best.
Obviously I’m going to put a pipe on it, and a jet kit.

I’m wondering if there is a lot of extra performance left in the stock heads, or are they pretty good from the factory? Just as an example, my raptor had a lot to gained form head work, but the LTZ 450 came pretty close to maxed out from the factory.

Is there a hotter cam set up avalible for the 1100? Looking low and mid range power. I wouldn’t mind a high RPM cam, but don’t want to sacrifice the low end power.

Who makes a reliable big bore kit? Basically I want to increase the displacement, and torque but still run pump gas. As a side note I hate wisco pistons, so anything made by wisco is out of the running. I’m not saying wiesco is junk, I’m just saying I have not had good experiences with them.

I have a fairly good understanding of engines, and have built many cars, and ATV's, and a couple bikes, but have no experience with the Katana so I figured I would ask the guys that know the Katana 1100 intimately.

[tone]

1216 kit is good in these engines for the road, plenty of power if set up correctly & wont produce too much heat, having said that a good aftermarket 19 row oil cooler is always a good idea gsxr cams, (or just the exhaust cam if you believe some ) 36mm carbs & a 5 deg ignition work well with this kit along with a decent pipe & free flowing filters

theres a couple of makers of the pistons but wiseco is believed to be the best in some circles, the other (cheaper) option is to use busa pistons but you will need to machine the head/barrels to restore the CR

hope it helps

[NiteMare]

if you want to push the power a little more the head could accept reworking, the amount of reworking depends on how much you are prepared to spend ...

posted this a few times now (no info just a picture to study)..

[Mojoe]

if you start modding much past 150hp, do yourself a favor and swap out the crank for a gixxer crank and clutch basket with the straight cut gearing. the cams are great in the kat engine (even better than the gix, imho), but the crank is inferior just because of the diagonal gear.

[suzy1052]

Get yourself a 88-89 Gsxr750 head and any any Gsxr oil cooled exhaust cam allthough the 89 750 seems to be the hottest profile.A 1st gen. 750 Katana head is the same as the Slingshot Gsxr.You will get the same size valves as the Gsxr1100 and more compression and higher intake tracts to provide a slight downdraft effect.Worked REAL good for me even though I used the stock Katana 1100 34mm carbs.

[loudnlow7484]

Get yourself a 88-89 Gsxr750 head and any any Gsxr oil cooled exhaust cam allthough the 89 750 seems to be the hottest profile.A 1st gen. 750 Katana head is the same as the Slingshot Gsxr.You will get the same size valves as the Gsxr1100 and more compression and higher intake tracts to provide a slight downdraft effect.Worked REAL good for me even though I used the stock Katana 1100 34mm carbs.

That is a beast of a setup (probably time for the slingshot carbs, though!)...... I've heard a lot of good things about putting the short-stroke 750 head on an 1100. What kind of compression do you end up with?

[suzy1052]

I dont know what the comp. ratio was but it pinged/dieseled at low rpm(1-3k) on anything other than 92 octane or above.Back then 103 was 2.50 a gallon so I would throw a gallon of that in with every fill up.After much reading I took a base gasket apart and used that section as a spacer to raise the cylinder block to lower the comp. slightly.I wouldnt run an ignition advancer with this setup.We all know that in stock trim this bike has awesome roll on but after this mod it was insane.BTW I fitted some 90 Gsxr calipers to help with the much needed braking.They bolt right on but didnt sweep the whole rotor but still stopped much-much(very highly much) harder than stock.I had a cheapo Yosh Zyclone 4-1 and K&N filter.After 5 or so jetting changes I ended up using the 110/112 stock jets with Factory Pro needles and there wasnt a flat spot anywhere.

[raptor ridin bubba]

Get yourself a 88-89 Gsxr750 head and any any Gsxr oil cooled exhaust cam allthough the 89 750 seems to be the hottest profile.A 1st gen. 750 Katana head is the same as the Slingshot Gsxr.You will get the same size valves as the Gsxr1100 and more compression and higher intake tracts to provide a slight downdraft effect.Worked REAL good for me even though I used the stock Katana 1100 34mm carbs.

This sounds like a very interesting set up, but I do have questions. I noticed you stated that it pinged with anything below 92 octane, but will it run well on 92? I want to continue to run pump gas, as race fuel is not readily available here in NY.

Do you know what size the chambers on the 750 head are compared to the 1100 head? If I had this info I may be able to calculate the the ball park of what compression it may end up with.

If I go to a 750 head will a aftermarket 1100 exhaust fit?

What RPM range did you notice the increase of power? Was it a very noticeable power increase, or was it just kinda like yeah well, maybe its got more power?

Thanks for the info.

[suzy1052]

I dont remember the size of the chambers except that the Slingshot's was smaller for more squish.It ran fine on 92 octane.There were not any type of drivability problems.All 750-1100 Suzuki oil cooled heads(SACS era) have the same exhaust spacing and spigot size so I used my 1100 Katana Yosh Zyclone.The power increase was no illusion on my part.Low and mid range was greatly increased with better throttle response(I know-these bikes had good response due to flat slide carbs)with the now added Gsxr top end rush.Everything you need to know including the comp. ratio of this setup(if you cant find it post your ?) can be found at oldskoolsuzuki.info and any parts interchangability questions you may have can be found if you google Frankensteins guide to oil cooled monsters.They are very eager to help if you ask and live and die by the oil cooled Suzuki motor.One member even sent me a hard to get part from the Netherlands and wouldnt take anything for it so I donated to the site.I no longer have this bike but still have great affection for it which is why I cruise this site more than the site for the bike I have now.

[Paolo]

Thanxs for all the great info ...guuuysss

[SupRnatural]

Back then 103 was 2.50 a gallon so I would throw a gallon of that in with every fill up.

Man, you are talking 18-20 years ago . Race gas is 7.75-8.00+ now for VP UL 101 at the pump. You must be talking about Sunoco race fuel, I used it a lot back in the day.

[suzy1052]

Actually it was back in 2001-2002 which is when I sold the bike.Here in the midwest (Iowa)racing gas was in the 2.50-3.00 range.