Cold starting problem - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

andrewcrocos1 · 06-26-2003, 04:37

I have a 351c which has done 25,000km since I fully rebuilt it. The motor ran beautifully. It was originally a 302. I changed the crank and rods. It has 302 closed chamber 2v heads with alot of work done to them. A 650cfm vac holley fed into a edlebrok performer. The thing was dyno and ran great. (200hp @ the wheels).
I have just replaced the mild cam with a 234, 244 duration and 560 inlet, 580 outlet lift. The cam was installed at 0 deg. New anti-pump lifters were installed. I have all so brought and regraphed a electronic ignition (XD) dizzy and coil. I have been instructed by the dizzy rebuilder to run the cam at 22deg BTDC on 98 ron fuel. It has no vac advance.
When starting, the motor turns over a few times and tries to fire and then continues to crank over slowly. The motor has fairly high compression. If I add some aerostart, the motor will eventually fire up. Once warm, the car is happy to idle at 850 rpm. (The cam has already been run in)
I know I need to get the motor tuned. But I'm trying to work out why it wont start easily. Most clevo's have problems trying to start when they are hot, not cold. I'm wondering if I need a high torque starter motor, to gain more cranking speed or wether I have another problem. I have tried changing batches of fuel, still no joy. I have good ignition voltage and spark and have tried all different static timing. Maybe not enough fuel???

brenx · 06-26-2003, 04:52

Sounds like it's either to advanced or too retarded. Also Clevo dizzies have 14 deg initial. So 22 deg on top of that initial 14 deg is 36deg total advance. Which sounds a bit much for that cam. Try dropping back 8 deg to 14deg so 28 total advance. If it fires up nice? Try advancing in small amounts 2 deg lots.

I run a F246 and I am only running 38deg total advance.

Although your right compression doesn't help in the starting stakes.

Mine turns over real easy running 10.5:1 compression. What compression do you think yours is running?

Brenden

AndrewsXR8 · 06-26-2003, 05:54

I had a windsor with 10.8:1 compression on a standard starter motor, and it turned over fine, your starter could be on the way out, or the battery may not be big enough. My cleveland is a pain to start, i thought due to a fuel leak out of the front bowl which i fixed last night, but it turns out that its constantly pumping fuel, even when not running, which means when i go to start it in the morning it has to crank over till it picks up fuel again.

andrewcrocos1 · 06-26-2003, 23:47

Thanks fellas. Brenden, I think it is running high 10 compression. I went out this morning and gave it 4 pumps of the accelerator and 3/4 choke and she fired straight up. My next mission is to find out wheather I should run a electric fuel pump (holley blue or a larger mechanical pump. I know I have to upgrade my fuel line to 10mm to prevent fuel strarvation. Any suggestions.

brenx · 06-27-2003, 05:58

Best bet is pay for a $50 power run on a dyno. They'll let you know whether it's getting enough fuel or not. A mates 351 was running a similar cam with the stock mechanical pump without any issues.

Brenden

TruBlu351 · 06-28-2003, 09:47

4 big pumps to the floor works every time for me! You're lucky to have a choke! I've got to do the tap dance on the throttle which takes great skill when she's cold!

If your car is revving fine at full throttle under load your fuel supply shouldn't be too bad. It wouldn't hurt to get the dyno run though.

I'm making a trick electronic air/fuel ratio gauge supplied by Jaycar electronics. It gives the actual A/F ratio readout on a small digital display. You can stick it somewhere on the dash (matchbox size). It will allow you to see if you've got your carby jetted right and have the best mixture for max power...........and if your engine is leaning out due to lack of fuel.

My hi volume Holley mechanical pump spat the dummy last week. I put on a new stock one it works fine. It puts out 9 psi at the carby and supplies enough for my warm engine (only go to 5500rpm).

Good luck.

andrewcrocos1 · 07-02-2003, 04:23

Thanks TRUBLU351. Car is great under load. I haven't taken it past 4000rpm yet. I'll wait for the dyno run. The cam makes max power @ 6000rpm and a mate of mine with a gt has fuel starving problems @ about 6000rpm in third and fourth. I'm also running a stock 6 cyl fuel line (5/16). I know I defiently have to upgrade this to 3/8 and I'm seriously looking @ a holley blue fuel pump. I let you know how I go.