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Robert Stoner
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East Alton, IL, USA |
Registered on 7/23/2003 |
6 posts |
1 Vehicle |
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Posted:8/1/2003 01:26 |
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Hi I got a 1949 Ford F-1 truck with a 302 it has a bad lag at take off.(NO LOW END)...
It has stock pistons bored 60 over,stock rods,Stock heads with crane roller rockers ,Shorty style headers, Edelbrock performer intake, 650 holly carb, the cam has 218-283 duration with a 447 lift,distributor is a point type converted to elctronic with a 40.000 volt coil.with a set advance(no vacum).Backed up with C-4 trans and a 2000 stall converter and B&M shift kit... The rear end is a 3:70 ratio.Open diff. with 225/70 tires.
It does fine once it gets rolling about 30 MPH... but under that it is a real slug bug.
It also has a .5 degree off set key in the lower cam gear .I installed this to try to help ,It did some but the problem is still there. any ideas or pointers would be appreciated.
Rob S |
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John Barrett
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West Palm Beach, FL, USA |
Registered on 1/31/2003 |
106 posts |
1 Vehicle |
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Posted:8/16/2003 17:32 |
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Quote: | Hi I got a 1949 Ford F-1 truck with a 302 it has a bad lag at take off.(NO LOW END)...
It has stock pistons bored 60 over,stock rods,Stock heads with crane roller rockers ,Shorty style headers, Edelbrock performer intake, 650 holly carb, the cam has 218-283 duration with a 447 lift,distributor is a point type converted to elctronic with a 40.000 volt coil.with a set advance(no vacum).Backed up with C-4 trans and a 2000 stall converter and B&M shift kit... The rear end is a 3:70 ratio.Open diff. with 225/70 tires.
It does fine once it gets rolling about 30 MPH... but under that it is a real slug bug.
It also has a .5 degree off set key in the lower cam gear .I installed this to try to help ,It did some but the problem is still there. any ideas or pointers would be appreciated.
Rob S |
What did you do to the heads ?.
What Compression Ratio do you have ?.
What Pistons did you put in ?.
I got a 302 H.O. that came with a set of stock 64CC heads, and Bored the Block 0.030" over, to make it a 306cid motor, with Stock Compression Ratio at or about 9.0:1, did not CC everything out at this time.
Below I CC'ed everything out & Mic'ed too.
The pistons I used came out PROUD of the cylinder hole 0.010".
Then what I did is have the heads Milled to give me 59CC, also put reciever grove (O-Ringed) in the block and used 4.060" * 0.041" Copper Head Gaskets (using NOS later), This raised my Compression Ratio upto 10.56:1, Stock valve 1.760" Int. & 1.460" Ext., Also had to have the intake Milled a little too, used a Holley 650cfm with Bigger pumpers installed.
Used a Ford Z303 Cam with 0.552 int. & a 0.552 Ext. lift, 7 degrees BTC, 41 degrees ABC, 51 degrees BBC, 3 degrees ATC, Duration is at 228/228, dead nuts set at 0 timing, not 5 degrees Advanced or retarded.
This left me on the dyno about 337hp @ 354 @ 5000rpm, With about 400 CFM induction air flow.
This left me with lots of clearance (Valve to Piston).
What I am trying to get at here is this, you would be wise to increase your Compression Ratio a little or back to 9.0:1 or better.
Now is that 5 degrees advanced or Retarded on the timing key ?., if you advanced it you would bring the piston closer to top or heads, this would increase your Compression a little not much.
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