1955 Chevrolet Q/SA Build

Dwight Southerland · 09-09-2020, 07:47 AM

Lyn Smith · 09-09-2020, 01:49 PM

When NHRA put the older cars back in the guide a few years back they raised the 1955 4bl HP from 180 to 200. It has been lowered some to 197. Needs to go further down, as the 55 265 has to use flat top pistons which means you have to use a cam with 230 degrees duration or less, or you will have valve to piston clearance problems. Mid way thru 1956 GM started building 265s with valve notches. They discontinued the over counter sales of the flat top piston about that time also. In the Jr Stocker days you could use the notched 265 pistons, but not now. Go figure.

Dwight Southerland · 09-10-2020, 08:39 AM

Find an OEM piston with notches, submit..

Lyn Smith · 09-12-2020, 11:30 AM

Dwight, I have talked to everyone at NHRA who would listen to get the notched piston okayed, but it always comes back No. I have the flat pistons,and the low duration cam purchased now so that is what I will run. Thanks for the suggestion though.

The ideaman · 09-21-2020, 10:43 AM

How much gear, 6.14's? Still have a powerglide?

Lyn Smith · 09-21-2020, 07:20 PM

I currently have a 5;57 and a turbo 350 trans with a 2.74 first gear. The little motor really likes a lot of gear.

jakane254 · 03-11-2021, 01:46 PM

Quote:

Originally Posted by Lyn Smith

I currently have a 5;57 and a turbo 350 trans with a 2.74 first gear. The little motor really likes a lot of gear.

Lyn, What style rear and posi unit are you running? I am building a 56 265 stick car.

Randall Klein · 03-12-2021, 04:28 PM

FWIW: at one time Speedway Motors in Lincoln, NE had a stockpile of NOS Firestone 7" slicks, I'll bet they would work

Just a thought

09-09-2020, 07:47 AM	#1
Dwight Southerland VIP Member Join Date: Dec 2001 Location: Arkansas - In the middle of everything. Posts: 2,001 Likes: 64 Liked 780 Times in 194 Posts	Re: 1955 Chevrolet Q/SA Build __________________

09-09-2020, 01:49 PM	#2
Lyn Smith VIP Member Join Date: Dec 2001 Location: Pontiac,il. Posts: 1,201 Likes: 283 Liked 973 Times in 195 Posts	Re: 1955 Chevrolet Q/SA Build When NHRA put the older cars back in the guide a few years back they raised the 1955 4bl HP from 180 to 200. It has been lowered some to 197. Needs to go further down, as the 55 265 has to use flat top pistons which means you have to use a cam with 230 degrees duration or less, or you will have valve to piston clearance problems. Mid way thru 1956 GM started building 265s with valve notches. They discontinued the over counter sales of the flat top piston about that time also. In the Jr Stocker days you could use the notched 265 pistons, but not now. Go figure.

09-10-2020, 08:39 AM	#3
Dwight Southerland VIP Member Join Date: Dec 2001 Location: Arkansas - In the middle of everything. Posts: 2,001 Likes: 64 Liked 780 Times in 194 Posts	Re: 1955 Chevrolet Q/SA Build Find an OEM piston with notches, submit.. __________________

09-12-2020, 11:30 AM	#4
Lyn Smith VIP Member Join Date: Dec 2001 Location: Pontiac,il. Posts: 1,201 Likes: 283 Liked 973 Times in 195 Posts	Re: 1955 Chevrolet Q/SA Build Dwight, I have talked to everyone at NHRA who would listen to get the notched piston okayed, but it always comes back No. I have the flat pistons,and the low duration cam purchased now so that is what I will run. Thanks for the suggestion though. Last edited by Lyn Smith; 09-12-2020 at 11:42 AM.

09-21-2020, 10:43 AM	#5
The ideaman Junior Member Join Date: Oct 2015 Posts: 10 Likes: 23 Liked 1 Time in 1 Post	Re: 1955 Chevrolet Q/SA Build How much gear, 6.14's? Still have a powerglide?

09-21-2020, 07:20 PM	#6
Lyn Smith VIP Member Join Date: Dec 2001 Location: Pontiac,il. Posts: 1,201 Likes: 283 Liked 973 Times in 195 Posts	Re: 1955 Chevrolet Q/SA Build I currently have a 5;57 and a turbo 350 trans with a 2.74 first gear. The little motor really likes a lot of gear.

03-12-2021, 04:28 PM	#8
Randall Klein Senior Member Join Date: Dec 2002 Location: Lincoln, Nebraska Posts: 785 Likes: 45 Liked 316 Times in 67 Posts	Re: 1955 Chevrolet Q/SA Build FWIW: at one time Speedway Motors in Lincoln, NE had a stockpile of NOS Firestone 7" slicks, I'll bet they would work Just a thought