View Full Version : How to make sure I don't lean out my new motor

05-14-2013, 11:16 AM
I'll be putting in the water in about a week. I'd like to start gathering advice on not blowing it up.

It's a big cam 502, 9.5:1. Iron head, victor jr intake. I'm not running an MSD box (have one but don't see the need right now). I'm going to break in on a 750 Edelbrock that was supposedly jetted up. I am considering a used 1050 Dominator. I will be running only 92 octance.

Not sure if I should change the oil after the break in. The builder said
run it the rest of the year.

I'm going to put it at 34 degrees. I got a nice new timing light. Springs and weights kit for the dist. All new ignition parts.

I expect I won't damage anything on the break in because there will be no load. Then I think I will go for test run. Shut down immediately and check a plug. Do I need to check all the plugs? Should I check the same plug each time?

Just looking at the insulator for color right?

The 1050 Dom was set up for a 502 as well. I'd rather make sure I get through the break in and everything is good in that respect before buying more motor parts. I'm not sure if 1050 is too big for me.

1. break in

2. Set timing

3. 3000 rpm test on the edelbrock, check plug(s), go in if pinging

4. go in

5. change oil?

6. put on 1050 Dom?

7. Go test run?

8. Order jet kit?

Should I mess with dist springs/weights before I break in? I have to replace everything in there anyways.


05-14-2013, 12:32 PM
Miike, I don't know much about your questions but in terms of number 4 I would change the oil and filter after an hour or so of run time. Oil/filters are cheap and you never know what got missed in the machining part of the process.

Protect your wallet, change the oil.

Good luck and have fun. :thumbsup:

05-14-2013, 01:46 PM
The Edelbrock carbs I have installed come with fairly mild engines in mind with their metering rods, springs, and jets. You will likely need to increase the springs a little and reduce the metering rod sizes to allow more fuel flow. These all come in the Edelbrock calibration kits for your specific carb. As you know, you will want to run too rich than too lean. Bill

I should add that changing the springs and metering rods is so easy on the Edelbrocks that you can do it in a few minutes without having to put it back on the trailer.

05-14-2013, 02:19 PM
Should I bother tuning that 750 carb?

05-14-2013, 02:35 PM
In my opinion, it might be enough CFM for the 502. Since you already have it, you might try it and get the calibration kit for it. Do you have the marine version or street version?

05-14-2013, 05:49 PM
Marine version

Metering rods and springs and jets kit is like $60

I can get a 1050 Dom for $350 shipped and the jet kit is like $20.

I think the edelbrock will be efficient but I want this motor to turn up to 6500 if I want it to. Not going with a large prop. The 750 prob won't do me up to 6500. Maybe I should dial in the 1050 or maybe the 1050 is a poor match.

05-14-2013, 07:06 PM
your not going to be able to put a 4500 series 1050 Dommi on an Edelbrock carb base pattern..

05-14-2013, 07:31 PM
You mean the Edelbrock Victor Jr intake won't take a Dominator?

Just Say N20
05-14-2013, 07:40 PM
I also don't know how the outdrive would handle 6,500 rpms. I would think it better to build it so max hp is no more than 5,400. Boats love torque, not necessarily a lot of high rpm hp.

05-14-2013, 07:43 PM
Perhaps where I'm propping I'll only get 5500 which is 84mph at 8% slip. That gives me 46mph at 3000.

CFM range for a 502 @ 5500

800 CFM @ 100% VE

660 @ 83% VE.

The only wonky thing is that my original 454 had a 750 Holley and at 5000 rpm it would require:

656 CFM @ 100%

545 CFM @ 83%

If they chose that much bigger of a carb, shouldn't I? Doesn't that justify needing the 1050? Or should I ignore that and go with what all the calculators say is adequate?

05-14-2013, 07:55 PM
You mean the Edelbrock Victor Jr intake won't take a Dominator? depends what you bought > http://www.edelbrock.com/automotive_new/mc/manifolds/chevy/victor-bb.shtml

a Dommi wouldn't be a smart choice here what-so-ever

05-14-2013, 08:10 PM
It is the rectangle port 454 manifold.

Should I hold out for an 850 or 950? I believe the HP500 carb is an 800 and seems to come up often on OSO.

05-14-2013, 08:32 PM
find a HP 500 carb or get a BG 800

05-14-2013, 08:44 PM
Just so you have a reference point, I am running a 780 Holley and so far I have only spun the stock 502 (basically a truck cam) up to about 4400 Rpm. 14.5 21p viper prop, Bounced around 68 mph with 3 adults and about 1/4 tank of gas.

05-14-2013, 09:21 PM
Ok I locked in an 850 Holley off OSO. Should fire right up. Not going to use the 750 Edelbrock.

Here is my strategy now:

1 install 850 carb
2 break in at 3000 rpm for 25 min
3 set timing to 34 at 2800
4 test run 3000 rpm
5 immediately stop and check plug(s?) (is checking just one ok)
6 if plugs ok, drive around for until 1 hour run time complete
7 change oil
8 launch again test run 4000 rpm
9 stop and check plug(s) (same plug? all plugs? different plug?)
10 if ok, run at 5000
11 if ok run at wot

does this sound like a good way not to lean out the motor?

05-14-2013, 09:28 PM
what do you consider a BIG CAM?

if it's a roller cam you really don't need that 3000 rpm ritual

05-14-2013, 09:42 PM
Its a solid lifter flat tappet cam

600 lift