Trying to put my motor together

dukebradbury · Joined: 13 Oct 2009 Posts: 185 Location: Spokane 5-mile

I am trying to finish up putting my 1776 back together. I purchased it used from a guy close to Seattle.

Came with some Italian 44 idf webers.

Jetting was
main--115
a/c----165
venturi-36

I just ordered some new jets from CB Performance
Main---130
a/c-----200
Venturi--32

What do you think about that to start with?

Also found some nice heads that came with the bus.
CB ported heads 40x35.5
Combustion chamber looks untouched. I measured them at 45cc.
I contacted CB and they said that they are around 55cc.
Deck Height is .050"
If 45cc is right, that puts my compression to around 9.5:1. Does this sound right?

Previous owner "believes" that the cam is an Engle 110

Thanks

dukebradbury · Joined: 13 Oct 2009 Posts: 185 Location: Spokane 5-mile

Cylinder head combustion chambers are at 45cc.
Deck height is .050"
Puts the CR at 9.3:1.

Sound high? Or will that be ok?

Long-roofs · Joined: 23 Aug 2007 Posts: 715 Location: valley

CR sounds real high to me, with todays gas.

dukebradbury · Joined: 13 Oct 2009 Posts: 185 Location: Spokane 5-mile

Yeah, thats what I am thinking!

I have a set of heads with 55cc combustion chambers with 40x35.5 valves. That would put my CR at 8:1. However, they are not ported.

I would like to have the flycut to about 50cc, putting my CR to 8.6:1

Also, possibly a port job.

Anyone local?

I know that the sky is the limit with $$ and cylinder head work, but what would a flycut run me?

Porting/polish?

Thanks

ONEBADBUG · Joined: 25 Oct 2003 Posts: 440 Location: Spokane

8:1 is still pretty high for a street motor. Since it is a bus, I would assume your focus is on durability, not speed, so porting is the least of your worries. I always polish the exhaust ports to help keep the engine cool. You can easily do that yourself.
BTW, my baja has an 1835 with (I think) 9:1 and a stock carb, and it won't run on normal pump gas. I have to put some race gas in it to keep it happy.

sandals · Posted: Fri Nov 19, 2010 7:52 pm Post subject:

By polishing, do you mean making things all nice and shiny? Or just cleaning up the flashing and smoothing the rough surfaces?

ONEBADBUG · Joined: 25 Oct 2003 Posts: 440 Location: Spokane

ONEBADBUG · Joined: 25 Oct 2003 Posts: 440 Location: Spokane

Alright, my real answer is:
To keep the engine cool, which is the #1 priority, you want all the parts on the inside to be as smooth as possible because it reduces the surface area.
So, I usually polish the tops of the pistons, clean up the exhaust ports, and polish those too. To "port" the intake is only appropriate for a race motor that will only be used in warm weather, where max power is a priority.
If you drive a car with polished intakes in cool weather, it will be more likely to have liquid fuel run right through it. That will harm the rings, thin the oil, and run like crap.

Just my take on it.

sandals · Posted: Sat Nov 20, 2010 6:28 pm Post subject:

Thanks. That is what I figured, as I have read many threads and articles about it. I just wanted another take on it. I may be doing some of this stuff this winter so the info is timely.

To the original poster of this thread, sorry for the hijack. I have nothing to offer you for your questions as I am no engine expert.

tball · Joined: 30 Apr 2010 Posts: 22

for the heads,port the intakes slightly(just clean up the casting marks)do not POLISH intakes ever.It will washh the cylinders out.How ever open up the exhaust just a bit bit.Polish the crap out of it!!!!!!!!!!Depending on the condition of your chambers and your skill level you can;unshroud the valves and clean up the chambers,then lap in the valves.Most just relap valves as headwork is an aquired skill espesialy in the chambers.Theres a tutoral by ohio tom on cal look.com that shows you how to do all this with a dremel.I have a headporting station at my shop but can say ohnestly say that ohios methods will net you results.Its how I did my very first set many years ago.Last,you can run a 10,20,30 or thousanths head shim to adjust your compression ratio down to 8.0 to 8.5. 9.3 will run like a banshee but high octane gas and total seal rings are a must.Maintenance issues are sure to follow.Plugs,valves,tuning ect are much more critical with comp ratios above 9.0 .8.0 is kinda my magic # for my street driven motors.Here is my baja motor.69x88,40 x 35 044s,full port and polsh,unshrouded valves,reworked chambers,relief valve guide humps,lapped valves,solid rocker shafts with swivel feet adjusters.120 engle cam,vw german lifters,toal seal rings,comp ratio 8.3.dual kads match ported manis,1&5/8ths baja header.009 with high rev points,one loose spring for custom advance curve.timing @10 degress.Nothing too fancy here,just a little bit in every department.desk top dyno gives me 91 hp.I think it may be slightly lower , I stop light ricers and big trucks all the time with a 30 inch rear tire,1st and 2nd gear are just hillariuos,I know this is a long post but information is knowledge.Good luck,take your time,and HAVE FUN!oh,I like the 32vents,and original jetting,switch it up on the fuel and airs to see what your best combo is.Lean is good but too lean is expensive.POP!Aloha.Tom.