Porting A Spree Case

[az_slynch]

Is it me, or does the spree case have the most ineffectual boost port ever?

I'm prepping FailSpree's original block for buildup with the standard upgrades (SB50 carb/intake/reeds, BBK, gears) and was starting to modify the case to maximise the benefit of these upgrades. Cleaned the flashing out of the case induction ports and reprofiled the rearmost port to expose more of the reed cage. Marked the case to match it to the 44mm BBK gasket, but I think I'll hold off on cutting until I get the 48mm BBK. I'd read on of Tjamz's 50mm Elite S build about the zen of maximizing the boost port performance. Upon cracking FailSpree's case, I found the shape of the house to be non-conducive to the boost port mods done by TJamz. I'll refer to the following image for reference:



If you look at the shape of the back wall of the case, it bends in past the vertical plane to follow the crankshaft, then bows back out into an oversized pocket before cutting back in to form a diminutive port. Has anyone bothered to improve the boost port on a Spree? I figure it would be useful on a kitted cylinder in order to help control engine temperature.

[tazland001]

No but I am intersted in seeing what you do. I am sure that you will get few good responses to this question.

Taz

[az_slynch]

Taz, I'm going to be picking up one of your 48mm kits shortly. Is it boost port size/shape any different than the 44mm kit? if it's close, I may just go ahead and shape the port based on the cylinder kit I have. Shame I missed out on the '88 Elite ES that was for sale in Phoenix a few months back, but I believe that the Spree can be made to zip with the right parts and tuning. Thought I had an idea for making a Spree ministroker from an '83-'84 Aero crank (39.3mm versus the spree's 37.4mm), but the cranks look too different.

BTW, the Jaingwayne AF09 Tact pipe is not a bolt on for a Spree as claimed. It will need to be modified.

[tazland001]

A stroker for the spree would be nice but the the air flow of the stock carb and muffler restrict the 48mm kit in my opinion. The 48mm has so much potentail for some great top end. I will have mufflers being made and then a intake manifold adapter for the spree. The variater for the spree is on hold for now. The performance muffler and the bigger carb will help alot on the top end. I have an idea how to variate a spree but it would kinda pricey...

Taz

[SPREEtown]

A stroker for the spree would be nice but the the air flow of the stock carb and muffler restrict the 48mm kit in my opinion. The 48mm has so much potentail for some great top end. I will have mufflers being made and then a intake manifold adapter for the spree. The variater for the spree is on hold for now. The performance muffler and the bigger carb will help alot on the top end. I have an idea how to variate a spree but it would kinda pricey...

Taz

are you going to out do the sb50 intake swap? any 44mm mufflers?

is modification of the case necessary for the 48mm kit?

[az_slynch]

are you going to out do the sb50 intake swap? any 44mm mufflers? Is modification of the case necessary for the 48mm kit?

I bought a used SB50P carb, intake and reeds. It does offer a small improvement in flow through the intake and the reeds are markedly bigger.

Noiseguy had designed a Spree pipe, but no longer makes them. I'm thinking about getting a Tecnigas Next for a Tomos A35 or A55 and reworking it to fit the Spree. Works nicely on my Puch E50, is designed for 50-70cc cylinders and has decent midrange and topend power.

Taz's kits are bolt-ons. I'm just fiddling with one of the motors I have laying around in an attempt to get even more zip out of the motor.

[ae86guy]

i built my own exhaust for my spree works well with low and top end check out wikispreedia some pics of my first attemps there i have a technocast exhaust as well to suit af18e i will be modding to suit my spree just interested in seeing how it works if its better than the other that i made then im giving the old one to a mate who just bought a spree trying to get him to buy the 48 bbk

[az_slynch]

i built my own exhaust for my spree works well with low and top end check out wikispreedia some pics of my first attemps there i have a technocast exhaust as well to suit af18e i will be modding to suit my spree just interested in seeing how it works if its better than the other that i made then im giving the old one to a mate who just bought a spree trying to get him to buy the 48 bbk

Saw the wiki on your pipe, looks pretty wicked. The pipe is key to making a fast Spree, the BBK is just a great way to make more high-end horsepower.

[tazland001]

can you post a pic of your muffler on the scoot?

Taz

[ae86guy]

heres my exhaust i made tried all sorts of shapes was told about this design by a guy who races chainsaws and builds racing go kart motors seems to work better as a all rounder others i made had either massive top end or vice versa i do have a technacast exhaust for a af18e which im gonna mod the header pipe to suit my spree as soon as i get more gas for the welder just want to see how it works compared to my home made pipe i chucked in a pic of the DJ1Rs factory expansion chamber exhaust Hows That Variator For The Spree Going

[az_slynch]

Dude, if you come across a spare NiftyFifty headset, let me know! I'd love to put one on FailSpree!

[tazland001]

I love those white walls. Sweeet. What BBK are you running with that muffler? And what is your top end now with that muffler?
Just curious????

Taz

[ae86guy]

44 bbk want a 48 but cant afford it at the mo dont have a working tach on it but it does rev a bit harder than stock tops out at 40mph between 25 and 40mph it has awesome power still takes off like a stock spree but pulls away at 12 to 15 mph and just keeps going had a race with a mate who just bought a 86 nifty fifty (spree) hes not to keen on modding it but ill talk him in to it