High Comp 120cc Build

The Mad Cadder

Well-Known Member
Joined
Sep 20, 2013
Messages
3,856
Reaction score
41
Points
48
Location
Detoilet Mi
samIam said:
Yea, I'm taking the springs down to the shop to get true number at .650.

Called lunati and they said 120-140 seat and 320-380 open. This is different info then before as I'm sure I didn't neglect this info before. Either way, things are getting fixed.

If you read my thread its the same spec they told me atleast twice.. I also got the same spec via email from comp, from crane off their site and posted links.. it's still pretty open ended 320-360 ..Thas obviously based on your cam grind and valvetrain components ..

Stay under 380 period and you'll be fine
Use beehives ..
 

samIam

Member
Joined
Aug 10, 2010
Messages
612
Reaction score
18
Points
18
Location
Minneapolis, MN
So on the hunch that I wouldn't have setup the springs that high off tolerance and someones numbers are wrong, I took the springs back to the shop and had them remeasure. My install height of 1.77 is actually 157lbs. My open height using .650 lift as the cam card says, they measure 368lbs at 2.42. I knew I couldn't have been that far off. Looks like they are close to spec and I'll leave them as is.

Wondering about valve clearance, I called Cadco about it and Chris told me that the pistons were first designed to run as a race piston for the 76cc heads so I should have nothing to worry about. He says there is .650 clearance with the piston at TDC with the 76cc head so I should have plenty of room with the 120cc heads.
 

samIam

Member
Joined
Aug 10, 2010
Messages
612
Reaction score
18
Points
18
Location
Minneapolis, MN
So I got everything back together and its running goooood. I haven't ran it much but I'm liking the lack of noise. They put a pipe plug in the leaky plug also.
One thing I'm having issues with is belt alignment and sizing and the belt squeal on start up. What is the correct bolt/stud/spacer combo that goes behind power steering resevior at the top of the head? Also, what is everybody doing for routing the wires in the engine bay? Its driving me crazy and These Xccel custom wires I just bought aren't long enough.




 

The Mad Cadder

Well-Known Member
Joined
Sep 20, 2013
Messages
3,856
Reaction score
41
Points
48
Location
Detoilet Mi
Not sure if you mean you have the precut wires
I get the kind you have to piece together and cut to length
It's a pain in the ass but the only way to end up with neat
plug wires.. I just use the looms that come in the kit

I have a set of red wires cut for the stock distributor for sale
if your interested
 

pila78

Well-Known Member
Joined
Dec 1, 2009
Messages
2,790
Reaction score
94
Points
48
Location
Saginaw michigan area
The wires I used came from Summit. I had called them about the wires, and the guy said " the Caddy guys have been using these" , so I ordered them & the fit very good. Screw that cut & fit crap ! :grumpy:

 

Member 3508

Active Member
Joined
Jan 1, 2012
Messages
1,611
Reaction score
18
Points
38
For belt alignment, i always have to custom shim stuff. I use fender washers till the spacing is right.

For wires, mine are kind of messy right now but they looked like this when i bought the car.

They have these sort of stand off plastic retainers that a very long bolt goes through. And then the separator clamps onto this plastic retainer thats attached to the valve cover. You can just see the first one on the corner of each cover. Getting the length right is key.
EDIT:
Added a second pic with different angle also.

Then the same retainer/separator combo is also bolted to the intake, so you get a neat cluster all the way across.

Its basically this. You can use the bolts they supply if you have factory or stamped covers. But i have cast which need much longer bolts;
https://www.summitracing.com/int/parts/tay-42502



 

dave brode

Well-Known Member
Joined
Oct 14, 2004
Messages
14,871
Reaction score
167
Points
63
Location
Frostburg, Maryland
samIam said:
What is the correct bolt/stud/spacer combo that goes behind power steering resevior at the top of the head?

Double ended stud, think rocker arm stud. Hex is thin, apx .180". I use a thin s/s washer on the hex, then put the bracket on, seems to work fine. In as pinch, you could use a bolt of proper length with .180-.210" worth of washers behind the bracket. You could also use threaded rod and a jam nut of you can find/make a jam nut that thin.

I used MSD cut to fit wires, plug wire ends bend to suit if an angle is better on some.
 

CaddyCrosley

Member
Joined
Jan 23, 2017
Messages
86
Reaction score
25
Points
18
Location
McPherson, KS
pila78 said:
The wires I used came from Summit. I had called them about the wires, and the guy said " the Caddy guys have been using these" , so I ordered them & the fit very good. Screw that cut & fit crap ! :grumpy:


Do you remember a part number for those?
 

samIam

Member
Joined
Aug 10, 2010
Messages
612
Reaction score
18
Points
18
Location
Minneapolis, MN
Thank you for the wire ideas. Good to see different wire routing cause I've struggled to get them how I want them.

I drove it today for the first time and its running great. Good temp, no noises at all, good oil pressure, drives like crazy. I also switched to the Autolite 63 spark plug, seems to like it but I haven't pulled one yet. The machine shop did a little porting of the intake also to help airflow near the carb base.

I was able to line up the power steering with some washers but I wonder what was there from the factory?

Thanks for the help yall.
 

samIam

Member
Joined
Aug 10, 2010
Messages
612
Reaction score
18
Points
18
Location
Minneapolis, MN
Well, things running good but the belts are giving me issues. A couple days ago, I raced a Challenger R/T on the highway and when I got back home the belts were flipped and riding on their back. The race went well, from about 60mph I slowly pulled away from him. I know he was surprised. Then he tried to fly past me but was unable to get to my fender...I love it. With my last motor I raced a R/T and he left me off the line so it feels good to get payback. I was at the rev limiter at 6400rpm. I haven't pushed a motor that hard in a long time, seemed to do well.

I just worry about the belts flying off, this is the second or third time the belts have flipped. Gotta figure out a different setup. Been reading on the serpentine belt setups people have here.
 

8ad-f85

Well-Known Member
Joined
Jul 25, 2014
Messages
1,787
Reaction score
277
Points
63
A bad dampener can flip belts.
I'd look to solve rather than completely change direction with a different setup.
I've seen a bent crank, broken main cap or cracked crank toss belts, but you just put your engine together so I wouldn't worry so much about that.
Those characterize by the rpm they flip at getting lower as the problem worsens.
Does your belt flip at a certain rpm point, such as from a slight imbalance or warp to a pulley?
Sometimes an inadequate alternator bracket adaptation will flex enough to do it.
 

The Mad Cadder

Well-Known Member
Joined
Sep 20, 2013
Messages
3,856
Reaction score
41
Points
48
Location
Detoilet Mi
If the belt gets worn they flip..
Pulleys out of align wear belts fast.. Went thru that
a bit last year with the Banana I had issue with the
water pump and 79 crank pulley had to shim the pulley
and grind the shit out of the pump took a while to figure
out the alignment issue. But I did..and the wearing flipping
belts phenomenon stopped

I hope you kept an eye on your oil pressure while you wound
it out to 6400 rpm... was that in high gear ??
 

samIam

Member
Joined
Aug 10, 2010
Messages
612
Reaction score
18
Points
18
Location
Minneapolis, MN
Well my dear caddy friends, I gotta come clean about what happened after I beat the hemi..

I did win, slowly pulled away at every pull we did(about 4). While somewhere around 110mph(?) and 6400 rpm, I hear a pop pop...temp shoots way up, I go from 14v to 12v. Get it pulled over about 45 seconds later and the whole side of the car is full of coolant(not even 20 minutes out the car wash). Pop the hood and the alt belt is hanging and the PS belt is flipped. Everything is connected but it so hot its pushing coolant out the front temp sensor. Get a new belt and not enough coolant and get it home around 240/250 degrees. 6 hours later, it still hasn't cooled down.

Takes 2 gallons of coolant to get full again. Been tinkering with it the last couple days and found the leak to be on the radiator where I capped the heater core outlet. Today was the day to start it up. Gets hot right away(4 minutes-ish) and the hoses have pressure right away. Compression test was in the works.
cyl 1...144
cyl 2...143
cyl 3...153
cyl 4...142
cyl 5...150
cyl 6...149
cyl 7...147
cyl 8...149

Seem pretty consistent but signs show a head gasket... Wondering if a blown intake gasket would do the same.

Help... :weeping:
Sincerely...the stubborn only child with too much pride.
 
Joined
Aug 25, 2008
Messages
586
Reaction score
15
Points
18
Pressure test the cooling system. What do the plugs look like ?
Was a compression test taken before the problems arose ?
Stuck thermostat ?
Funny engine noises ?
Oil pressure o.k. ?
Head bolts tight? (or not ?)

John
 

samIam

Member
Joined
Aug 10, 2010
Messages
612
Reaction score
18
Points
18
Location
Minneapolis, MN
I'll pressure test the coolant, I have the kit. Plugs look good, a little dark but nothing that stands out. All about the same color. Oil pressure still great, startup is about 55 like always, warm is 30/40 like always. No funny engine noises. I did a compression test a couple pages back. Can't remember what they were but the engine temp was opposite and the throttle wasn't open like it was today. Maybe a stuck Stat because even with overheating, the top hose was cold. I pulled the temp sensor and there was coolant behind it, back of passenger head. I haven't pulled the valve covers yet but outside head bolts are tight. Today's compression test was done with the motor over 200 degrees. It started getting hot, I shut it down and did the test.

The Alt and pulley brackets were loose after the race. I have a bad harmonic vibration in the rearend that goes away if I change loads. Like going around sweeping turns and Lane changes make the vibration stop. Going straight makes vibration. This is the root of the problem.

I beat that hemi tho...lol
 
Top