Re: Part numbers for 1970 LT1 cam
Just to add this into the current discussion going on.
The engine in my car is a 300hp configuration .040 over 327 with upgraded connecting rods (Scat); flat-top hyperutectic pistons (KB), 461 heads (1.94 intake, 1.6 exhaust....(exhaust opened up to 1.6)...) pocket ported, gasket matched, etc., and running with an LT-1 cam.
Why use the LT-1 cam in this engine? ..
I've always liked solid lifter cams. In reading prior forum threads here and over on the CF forum, the LT-1 seemed like a good 'not too big' choice to go with. The wider 116* LSA looked good for not having so much unburned fuel mixture passing through the exhaust during overlap.
The idea was to have some fun 'winding it up' from time to time while the car is still in my hands. When the time comes to turn the car over to my daughter, the LT-1 would come out and be replaced with the hydraulic 929 cam. With that in mind, if the LT-1 cam didn't work out, initially, it would have been pulled and replaced with the 929.
With low end performance a key consideration, the LT-1 has worked out very well in this engine, IMO. Engine idles at 1000 rpm, @ 13.5 vacuum reading. The timing curve was bumped up along the lines of the 365 hp advance curve spec. .. This combination likes a lot of initial ignition advance. Initial timing set at 18* advanced.
With 4:11's in the rear, the engine would wind to 6K+, no problem. With 3:08's in the rear now, it takes a little longer to wind up but overall performance is very good. On a road trip up to WA a few months ago with speed kept between 60-65 mph, fuel mileage came in at 19.5 . . Running 70-75 mph, fuel mileage drops off considerably. The engine runs fine on regular gas - no detonation issues.
John
edit to add:
GM dealer over the counter price for a '151' cam was 30-35 bucks, in 1968. I remember the cam came in a white tube with GM blue color lettering on the outside. The cam went on loan to a friend who would replace it with same, later. .. Never saw the guy again! . .
Just to add this into the current discussion going on.
The engine in my car is a 300hp configuration .040 over 327 with upgraded connecting rods (Scat); flat-top hyperutectic pistons (KB), 461 heads (1.94 intake, 1.6 exhaust....(exhaust opened up to 1.6)...) pocket ported, gasket matched, etc., and running with an LT-1 cam.
Why use the LT-1 cam in this engine? ..
I've always liked solid lifter cams. In reading prior forum threads here and over on the CF forum, the LT-1 seemed like a good 'not too big' choice to go with. The wider 116* LSA looked good for not having so much unburned fuel mixture passing through the exhaust during overlap.
The idea was to have some fun 'winding it up' from time to time while the car is still in my hands. When the time comes to turn the car over to my daughter, the LT-1 would come out and be replaced with the hydraulic 929 cam. With that in mind, if the LT-1 cam didn't work out, initially, it would have been pulled and replaced with the 929.
With low end performance a key consideration, the LT-1 has worked out very well in this engine, IMO. Engine idles at 1000 rpm, @ 13.5 vacuum reading. The timing curve was bumped up along the lines of the 365 hp advance curve spec. .. This combination likes a lot of initial ignition advance. Initial timing set at 18* advanced.
With 4:11's in the rear, the engine would wind to 6K+, no problem. With 3:08's in the rear now, it takes a little longer to wind up but overall performance is very good. On a road trip up to WA a few months ago with speed kept between 60-65 mph, fuel mileage came in at 19.5 . . Running 70-75 mph, fuel mileage drops off considerably. The engine runs fine on regular gas - no detonation issues.
John
edit to add:
GM dealer over the counter price for a '151' cam was 30-35 bucks, in 1968. I remember the cam came in a white tube with GM blue color lettering on the outside. The cam went on loan to a friend who would replace it with same, later. .. Never saw the guy again! . .
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