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Discussion Starter #1
383 staterted up today crate engine, getting a lot of black smoke and all the plugs are black. Blueprint engines use a 750 CFM edlebrock, this was purchased from summit thus for some reason after running and making many adjustments she is running to rich..

Engine sounds strong but she isnt dialed in to where you can truly feel the horse power, could this be a combination of the carb and an older MSD muti spark external box issue?
 

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Evan,

First thing is timing, your initial and total.

MSD make sure you run power and ground straight to the battery.

Second carbs transfer slots .020 on the butterfly's and all mixture screws out about 1.5 turns.

What do you have the timing set at right now.
 

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MSD boxes either work or don't work. Your's is working.
Use a vacuum gauge to intake vacuum and adjust for highest reading, both in fuel mixture screws, from Skeeter's suggestion of 1.5 turns out, a good starting point, and initial timing, advance it, CCW on the body.

Next, look down the air horn of the carb to ensure there is no fuel dribbling from the venturi booster. If there is, remove the carb top, easy to do on an Eddy, lower the fuel level.

Since the plugs are blackened, you might need to change them, unless you can get some road miles on them to clean them up.
 

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As stated above, msd works or it doesnt!!..is the carb you have new??..sounds like she need a little rich lean adjuxtment on the carb!!
 

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Discussion Starter #5
First "thank you all so much"

well the shop is adjusting the distributor by ear as they say its msd, and they have tunned the carb but than they started saying that i have an electric fuel pump? im like so what? engine sounds strong but seriously i dont feel any 430 hp at all, and the tires dont really lite up like i was expectingthem to, im not confident that they can tune the vehicle properly as they are doing it by ear, no timing light etc, they calim it could be the carb do to jets and the plugs being black but that could also be initial burn off or something due to initial start of the crate engine..

if the engine does get dialed in correctly today and i still dont feel the diffrence in the hp when the engine was dynod at 430hp than im thinking sence i did the engine and the transmission that maybe my drive shaft and or rear end needs to be looked at, as the engine does sound strong and the compression is high on all cylinders..
 

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383 staterted up today crate engine, getting a lot of black smoke and all the plugs are black.
When an engine is assembled there is a heap of lube used ...cam , pistons, rings, etc etc.

Guess I'd only do that if I really knew the guy was good...
I would immediatly take that as...dont touch my bloody engine m8

well the shop is adjusting the distributor by ear
Thats BS u end up over advancing, and on a new engine, not preheated the chances of collapsing a piston skirt are real high....


Set mixture screws and idle speed screw to middle of factory spec, adjust the sec set screw till you get a reasonable idle, dropping the intial advance back as low as possible.
Check that the VA is full in at idle speed.
Then fine tune the idle mixture screws keeping with factory spec tolerances, and as low as possible idle advance.
Then check you have the curve setup within ball park of 36 degs (no VA) at approx 3000/3200 rpms..dont change the intial, add more degrees to the curve.
 

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Discussion Starter #9 (Edited)
the carb isn't opening up all the way due to an after market "foot" i have over the gas pedal, additionally we drove the4 vehicle to another hot rod shop accross town, the mechanic there adjusted the carb and is goingto take the distributor out tommorow and put some diffrent springs on the distributor which will assist the vacumm better.
 

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You said you have an electric fuel pump? The eddy is set up for about 6 to 7 psi of fuel pressure going to it. So with out a regulator it would probably be spilling fuel out.

I too purchased a a 383 blue print fully dressed from Summit. The motor was on the dyno and came with a print out. It puts out 405 hp and 440 ftlbs of T. It ran pretty good out of the crate. I am running a MSD on it. I did change out the springs in the dist. to a light silver and blue and set my initial to 15 with a total of 34. My 750 eddy has the mixture set at about 1.5 turns out. I did up the jets to a 110 on the secondaries and left the 110s on the primary. I did try and run a 113 on the primary but it seemed just a hair too much.

Don't let anyone bull **** you and say I can set it by ear.

Once I set my initial and swapped out the springs for the advance I found all sorts of torque and tire spinning power. I have 383 in it and it will chirp tire with the th350 in second and third.

I really haven't laid into it yet, still breaking it in

Good luck
 

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Discussion Starter #13
Thanks, at this junction and after reading all the posts the dialing in of the vehicle is very important they got the engine in the car thus i will look around for a berrter place that really knows how to tune up the car properly.

I honestly was told in the past that with the msd set up and a stronger CAM that it was some how diffrent when setting the timing with the exception of changing out exterbal parts etc i am a novice in that area. I think i will call around and query the shops expertise versus simply dropping the car off at a shop that looks good this time as they couldnt even fit headers on the car. I concur with the fuel regualtor i think she is getting to much and the regulator put the exact amount into the carb the right time, and thus the timing and thus the air and fuel mixture must be correct or they are seriously wasting time as the blue print engine lacks hp right now... will not chirp tires right now at all but sounds loud..
 

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Rule of thumb.. back to basics.
higher the compression lower the advance (and faster)
higher the octane the more advance (and slower)
It is the DCR that is important...a higher rpm cam (increased duration/overlap) the lower the CR at low rpms and cruise and visa versa.
So when u get to idle, the engine becomes very inefficent and rough idle.
Hence why most curves come off reasonably fast, then flatten off about 2000/2500 rpms till they reach around 3000/3800 rpms and added VA at cruise lower dcr.

Also carbs are 2 separate carbs in one...there is the power circuits that only work when the car is moving above idle rpms
And the idle circuit that only works at idle (idle screw and mixture screws)
Hence the idle advance and under power advance are separate, and also at cruise with lower dcr another advance curve with the VA.
 

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Discussion Starter #15
thanks for all the replies everybody, i got a call late tonight and was told they had driven the car accross town to another shop and replaced the distributor springs and adjusted the carb etc and now the car really kciks tail and burns the tires pretty much they said that after replacing some hard springs on the distributor the vacumm opened up and that the car has serious power now?

I am hoping to get her back on saturday i wasnt able to break away from my military unit today to go and get her, lietrally i was stuck completeing a report all day and night they couldnt believe it since i have been down there every day for the last 3 weeks, but i was on post deployment leave so when ever you get back you know they are waiting to work the dog out of you and we dont have any clock watchers at my unit lol... the damm car better have some balls after this 5k project to go from a 327 to blue print 383
 
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