Tell me more about my Carb/engine

denpo

Carburated Nihilist
Joined
Jul 14, 2010
Messages
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Location
Montreal, QC
While I'm getting more knowledgable about suspension and drivetrain everyday, I'm still a freaking noob when it come to engine.
So Here is pics of my engine the former owner have made built for him.
Tell me more about it, especially about the carb (allegedly a Holley 850cfm), is it single or double pump, is it normal the secondary vaccum is not plugged, etc etc....
All i know so far it that's a 350 bored .30' over, with forget pistons and a very agressive cam.
All you can tell me from the pictures, just tell it, the more I know about it the better.
Thanks
thum_16554c92fd4c233be.jpgthum_16554c92fd4d540fe.jpgthum_16554c92fe2437555.jpgthum_16554c92fe284d524.jpg
 
The carb is easy- on the front of the airhorn, left side, there are some numbers- (3310,4130, or like that) that will tell you what model the carb is- from there you can go to Holley's website and get the info on that.

On the left rear of the block is a casting number- look there and at the right front, at the head mating surface those numbers will give some insight as to where the block was originally.

Casting numbers for the heads are on the surface of the head under the rocker covers.

Those numbers won't help as far as knowing what the full combination is, but will provide some help.
 
850cfm is huge for a 350, in combination with that intake (looks like a Edelbrock Victor) and the agressive cam it's likely going to run like crap below 2500rpm but it should make good power at higher rpm... I hope you have a manual tranny, I would not expect this engine to be very street-friendly, especially with a auto trans...

I'd replace the alternator bracket "spacers" with something other than hex nuts and replace the fuel line with something that's a little safer before you drive the car....
 
850cfm is huge for a 350, in combination with that intake (looks like a Edelbrock Victor) and the agressive cam it's likely going to run like crap below 2500rpm but it should make good power at higher rpm... I hope you have a manual tranny, I would not expect this engine to be very street-friendly, especially with a auto trans...
I dug up the P/O bills and started googling the part's #, I guess I have to ask people to find answer by myself *facepalm*
So here's the setup :

Intake Team-G
Patriot 2180 performance head
Forged crank
Forged piston
Forget I-beam rods
Performance bearings
3500 torque converter

I could even get a CR approximation (couldn't find the gasket thickness), I might be around 10.4:1

Couldn't find info on the cam setup, aggressive I'd say from how it idles.

Manual trans, man, I'd love to, so far I'm stuck with the TH350+shift kit. I'm european, I grown up with manual trans. Maybe this spring, if I can afford, I'd opt for a TKO500 or a T56.

All this was the previous owner setup, not mine.
Run like crap at low RPM ? maybe, don't have much reference, but when I hit the pedal, god it pushes hard.
The setup was for drag racing, not really MY goal (sporty cruising), but before buying it I only tried stock vette, which i find to be sluggish to say the least.

Once I'm done with the frame rebuild, I might do something with the engine setup, and i'll need input from you guys.
Still have to read that "How to rebuild the SBC" book I bought, but from what I understand putting a milder cam, a more low-RPM-friendly intake and maybe a smaller carb would do the job without dismantling the whole engine.
Making a stroker would be awesome too, but that looks like too much for for me so far.

I'd replace the alternator bracket "spacers" with something other than hex nuts and replace the fuel line with something that's a little safer before you drive the car....
Thanks for the tips MYBAD, yeah the spacer is bubba's work I'll get one custom made.
Fuel line is on my frame swap to do list, I'll take care of that.
 
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try to find out what pistons he used, then we can determine what the compression ratio is. If it's too high you have to be careful with a mild cam - you might run into detonation problems.
Just assuming some numbers here:
Your 2180 Patriot heads have 64cc chambers. Let's say the bore is 4.030", decked block (pistons .010" in the hole) with flat top pistons you're at around 10.8:1 CR and with a 3.5cc domed piston you're at 11.2:1 CR.

For drag racing it's not a bad setup, just not my first choice for a street driven car. The 3500 stall converter helps, see how you like it when you get it on the road.
 
try to find out what pistons he used, then we can determine what the compression ratio is. If it's too high you have to be careful with a mild cam - you might run into detonation problems.
Just assuming some numbers here:
Your 2180 Patriot heads have 64cc chambers. Let's say the bore is 4.030", decked block (pistons .010" in the hole) with flat top pistons you're at around 10.8:1 CR and with a 3.5cc domed piston you're at 11.2:1 CR.

For drag racing it's not a bad setup, just not my first choice for a street driven car. The 3500 stall converter helps, see how you like it when you get it on the road.
The piston are flat -5 cc.
http://www.jegs.com/i/SRP/867/138081/10002/-1
The compression calculator give me 10.4:1, but still I don't know how thick is the gasket.
 
Usually the gaskets are .040" compressed thickness, that would be 10.4:1 CR with -5cc pistons, 64cc chambers and a zero decked block. If the pistons are .010" in the hole then the CR is 10.15:1 acc to the calculator.

With a thick gasket like many Felpro gaskets (.040-.050 compressed thickness) you should have no problems if you decide to install a milder cam later. But again, wait and see how you like it when you drive the car, if you're planning on a TKO it will change the game quiet a bit.... an engine with a aggressive cam is much more driveable with a 5spd
 
Isn't .02-.025 standard for piston depth? Why are you assuming .01?

Good thing you got those performance bearings! Those are good for 40hp. :lol:

Looks like a sweet setup, where do you shift it? I'm assuming it's a hydraulic cam if he didn't tell you that you have to adjust it. Get it dynoed, see what it's really doing.
 
Also, assuming the guy who built the engine knew what he was doing, a camshaft with 240 degrees of actual duration, or more, calls for a single plane manifold, which you have. So I would guess your cam is around a .540 lift cam. Maybe less, but I would doubt much more. Those heads are decent, but not the top of the crop, and you can't do much better with a 91 octane motor and 10:1 compression.
 
PS, rent a tube bender, flaring tool and buy some tube, ends and o-rings, then get rid of that high pressure rubber line.
 
Isn't .02-.025 standard for piston depth? Why are you assuming .01?

Yes, .025" is stock but he says he's got forged (aftermarket) pistons so the block was bored and likely decked... some deck it to "0" and some don't ... I just took .010" to run the numbers
 
That is the correct and proper way to make a fuel line. It takes a some practice to get it right, but once you get it there, it's bulletproof.
 
Also, assuming the guy who built the engine knew what he was doing, a camshaft with 240 degrees of actual duration, or more, calls for a single plane manifold, which you have. So I would guess your cam is around a .540 lift cam. Maybe less, but I would doubt much more. Those heads are decent, but not the top of the crop, and you can't do much better with a 91 octane motor and 10:1 compression.
I'm reviving this thread because I finally found my cam specs:

Comp cam 12-678-4
Cam Style: Mechanical flat tappet
Basic Operating RPM Range
: 2,400-6,800
Duration at 050 inch Lift
: 244 int./252 exh.
Advertised Duration
: 282 int./290 exh.
Valve Lift with Factory Rocker Arm Ratio
: 0.520 int./0.540 exh.
Lobe Separation (degrees)
: 110
Intake Valve Lash
: 0.016 in.
Exhaust Valve Lash : 0.016 in.

Looks like you was spot on :thumbs:
 
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