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  #166 (permalink)  
Old 07-12-2013, 05:22 PM
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Quote:
Originally Posted by Dajerseyrat View Post
The intake is some custom cast aluminum welded and epoxy job..The gears in the Jerico are
1-308
2-193
3-134
4-1 to 1

Rear end is a 308
I am getting a picture now of why this car is such a pig to drive.

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  #167 (permalink)  
Old 07-12-2013, 05:30 PM
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Originally Posted by F-BIRD'88 View Post
I am getting a picture now of why this car is such a pig to drive.
It seems to be geared for top end speed right?
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  #168 (permalink)  
Old 07-12-2013, 05:47 PM
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Ya the3 gearing and gear spread are way off for a street machine with that cam.
Needs 4.56's. A 5 speed trans would be sweet. Rear ratio x first gear ratio should be in the 10.5:1 to 11.50:1 zone. The 3.08"s are killing it... bad ratio spread too. That 260-264 107LSA cam wants to rev.

What is/does the plenum of the intake look like,, with the carb off. There may be a problem there
Fuel distribution at low rpm. Some one off custom racey intakes make good WOT power but suck at low speeds.
Often the plenum is too smooth for its own good.
Measure the carb vernturii ...

The carb needs a tweek so it can idle with the throttles positioned correctly at idle.
When the throttles are too far open when its at idle, its gets all screwed up (fouls plugs)

Adding air bleed thru the PCV port on the car base corrects this. (easier to do than drilling throttles blades)
These 650 carbs were origionally made to employ a PCV valve. When the PCV valve is eliminated they get screwed up.
The cam makes it even worse. But its fix able.
You need to add a air bleed that does the same air leak as a PCV valve did. Then fine tune that as required.
This allows correct throttle T slot exposure at idle and correct idle circuit function.
Some people drill the primary throttles to get this extra bit of idle air leak/flow. I don't. I get it thru the 3/8" PCV port on the base. I suggest you do the same. This also trims/dials in the idle circuit AFR.
Hard to do over the internet.

Last edited by F-BIRD'88; 07-12-2013 at 05:57 PM.
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  #169 (permalink)  
Old 07-12-2013, 06:06 PM
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A set of 4.10's 4.30's would fix a lot.
Is this trans staying or....?
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  #170 (permalink)  
Old 07-12-2013, 06:52 PM
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Quote:
Originally Posted by F-BIRD'88 View Post
A set of 4.10's 4.30's would fix a lot.
Is this trans staying or....?
Not sure..If I wind up selling the engine and trans combo, I may go with a fuel injected LSX engine and 6 speed. But who knows..For now the set up is staying the way it is. I may swap a cam or the engine to my 355 over the winter, but that will require some fabrication and altering the position of the steering rack.
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  #171 (permalink)  
Old 07-12-2013, 06:55 PM
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Quote:
Originally Posted by F-BIRD'88 View Post
Ya the3 gearing and gear spread are way off for a street machine with that cam.
Needs 4.56's. A 5 speed trans would be sweet. Rear ratio x first gear ratio should be in the 10.5:1 to 11.50:1 zone. The 3.08"s are killing it... bad ratio spread too. That 260-264 107LSA cam wants to rev.

What is/does the plenum of the intake look like,, with the carb off. There may be a problem there
Fuel distribution at low rpm. Some one off custom racey intakes make good WOT power but suck at low speeds.
Often the plenum is too smooth for its own good.
Measure the carb vernturii ...

The carb needs a tweek so it can idle with the throttles positioned correctly at idle.
When the throttles are too far open when its at idle, its gets all screwed up (fouls plugs)

Adding air bleed thru the PCV port on the car base corrects this. (easier to do than drilling throttles blades)
These 650 carbs were origionally made to employ a PCV valve. When the PCV valve is eliminated they get screwed up.
The cam makes it even worse. But its fix able.
You need to add a air bleed that does the same air leak as a PCV valve did. Then fine tune that as required.
This allows correct throttle T slot exposure at idle and correct idle circuit function.
Some people drill the primary throttles to get this extra bit of idle air leak/flow. I don't. I get it thru the 3/8" PCV port on the base. I suggest you do the same. This also trims/dials in the idle circuit AFR.
Hard to do over the internet.

When you say measure the venturi, do you have an illustration of exactly what points to measure from? Do you also need the baseplate openings? I removed some of the smaller jets from the blocks but they were not stamped. Also this carb appears to not have removable idle air bleeds like a Holley would..
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  #172 (permalink)  
Old 07-12-2013, 08:08 PM
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Actually just measured them, they say 45R on them and measure .450
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  #173 (permalink)  
Old 07-13-2013, 01:13 PM
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the venturi is shown here
A 650 has a 1/4" pri and 5/16"sec venturii
a 750 has 3/8" pri and sec venturi
a 850 has 9/16" venturi
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  #174 (permalink)  
Old 07-13-2013, 01:21 PM
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Quote:
Originally Posted by Dajerseyrat View Post
Not sure..If I wind up selling the engine and trans combo, I may go with a fuel injected LSX engine and 6 speed. But who knows..For now the set up is staying the way it is. I may swap a cam or the engine to my 355 over the winter, but that will require some fabrication and altering the position of the steering rack.
This car will be worth nothing by the time you are done.

Why would you butcher the car to fit a oil pan. make the oil pan fit the car.

if you want a car your wife will like, get a Chevelle convertible. This is not a wifey cruiser car and nothing you can do will change that.
If you want a LS motor with a 6 speed just go buy a new 2013 Vette convertible. You wife will like that one.

Did you ever solve the crank trigger/ignition box issues?

Converting this car to a EFi system is a possibility too but I would change out the cam at the same time.
A EFI system that bolts on to the intake would keep the car looking all "road race"
But really all you need is a proper built (750HP based) carb and the street cam.
(Keep all the old stuff) You need not throow out the baby with the bath water, to fix this car.

Last edited by F-BIRD'88; 07-13-2013 at 01:39 PM.
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  #175 (permalink)  
Old 07-13-2013, 01:49 PM
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It's been quite a while since I visited Hotrodders. It's funny how things never seem to change. Guys are still jumping in neck deep without learning to swim first!
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  #176 (permalink)  
Old 07-13-2013, 04:46 PM
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Quote:
Originally Posted by F-BIRD'88 View Post
This car will be worth nothing by the time you are done.

Why would you butcher the car to fit a oil pan. make the oil pan fit the car.

if you want a car your wife will like, get a Chevelle convertible. This is not a wifey cruiser car and nothing you can do will change that.
If you want a LS motor with a 6 speed just go buy a new 2013 Vette convertible. You wife will like that one.

Did you ever solve the crank trigger/ignition box issues?

Converting this car to a EFi system is a possibility too but I would change out the cam at the same time.
A EFI system that bolts on to the intake would keep the car looking all "road race"
But really all you need is a proper built (750HP based) carb and the street cam.
(Keep all the old stuff) You need not throow out the baby with the bath water, to fix this car.
Ignition issue fixed. The pickups werent phased properly. The plenum on this car is definitely custom and has alot of porting work done to it. Was thinking of a divided plenum like some suggested.

So smaller cam, with say a 410 gear in the rear and a fuel injection set up with a vacuum advance distributor would make it more streetable? Wouldnt the 410's make it rev higher than it does now?
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  #177 (permalink)  
Old 07-13-2013, 04:48 PM
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Quote:
Originally Posted by F-BIRD'88 View Post
the venturi is shown here
A 650 has a 1/4" pri and 5/16"sec venturii
a 750 has 3/8" pri and sec venturi
a 850 has 9/16" venturi
I measured at the top opening and got .450 am I supposed to be measuring the outside diameter or inside diameter?
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  #178 (permalink)  
Old 07-13-2013, 04:50 PM
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Originally Posted by F-BIRD'88 View Post
This car will be worth nothing by the time you are done.

Why would you butcher the car to fit a oil pan. make the oil pan fit the car.

.
Well the very front of the oil pan on a regular oil pan just hits the steering rack. The rack would have to be lowered about 3/4". I wouldn't call that butchering the car really. The front of the dry sump oil pan is flat, and stepped to clear.
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  #179 (permalink)  
Old 07-17-2013, 02:23 PM
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I have clairification on this Custom camshaft and how to get it, now, if you are interested.

it is not a Bullet Cam. it is a Custom grind UD Harold camshaft. You order it thru him.
All you got to do is make a phone call and order it from "UD Harold" .

Then Lunati Cams custom makes this custom roller camshaft to UD Harolds pro-priority camshaft specs, just for you.
You cannot buy this camshaft from a cam catalog.

if you are not interested there is no point in giveing you the Contact information.

This camshaft has a lot less duration and valve overlap but serious valve lift. It is a street proven design
tested over 5 years in a serious street motor, very similar to yours. It will "drive" a hell of a lot better. and Go like hell.

He ("UD Harold") Harold Brookshire may even want to tweek the exact cam specs a bit, just for you.
Leave that up to him.

You got a good racing cam in your car now.. Now you need the right great custom grind "street cam".

Last edited by F-BIRD'88; 07-17-2013 at 02:31 PM.
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  #180 (permalink)  
Old 07-17-2013, 09:43 PM
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Originally Posted by F-BIRD'88 View Post
I have clairification on this Custom camshaft and how to get it, now, if you are interested.

it is not a Bullet Cam. it is a Custom grind UD Harold camshaft. You order it thru him.
All you got to do is make a phone call and order it from "UD Harold" .

Then Lunati Cams custom makes this custom roller camshaft to UD Harolds pro-priority camshaft specs, just for you.
You cannot buy this camshaft from a cam catalog.

if you are not interested there is no point in giveing you the Contact information.

This camshaft has a lot less duration and valve overlap but serious valve lift. It is a street proven design
tested over 5 years in a serious street motor, very similar to yours. It will "drive" a hell of a lot better. and Go like hell.

He ("UD Harold") Harold Brookshire may even want to tweek the exact cam specs a bit, just for you.
Leave that up to him.

You got a good racing cam in your car now.. Now you need the right great custom grind "street cam".
Absolutely interested. PM me his contact info. I plan on swapping the cam out eventually. I like the way this motor sounds and pulls, so if I would drive better, That would be awesome. Im assuming I can reuse all of my current driveline stuff?
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