Building a new 355 SBC

[econo racer]

Will have a stock cast crank eagle rods and a set of OLD Lunati Taylor flat tops forged. Anything speacial about these pistons? I have had them stored for decades. They do not have wrist pins. I think there 2.97 7.50 pins will check. Will they take a 175 shot of nos?

[mag2555]

More info is needed here!

How much hp will the motor look like its going to make without the NOS and how high will it be spun up?

Modern pins should be no sweat a the 700 hp level, but long before that your weak link is that cast Crank followed by the block if you do not have 4 bolt splayed main caps!

Those old Pistons are likely very heavy and need .008" wall clearance.

[LSP]

Will have a stock cast crank eagle rods and a set of OLD Lunati Taylor flat tops forged. Anything speacial about these pistons? I have had them stored for decades. They do not have wrist pins. I think there 2.97 7.50 pins will check. Will they take a 175 shot of nos?

The Lunati Taylor pistons I know about were for Super Stock drag racing, about 345 grams, worked well at .005"-.006" clearance measured .500" from shirt bottom, and not at all designed for nitrous use.
Post a few pics of them if you can.

[econo racer]

I'm sorry I don't know how to do pictures. Its a 2 bolt main block. The heads will probably be world products 200 cc int heads. 2.02 & 1.60 valves angle plug too. Looking to shifting around 6500 rpm. Super Victor intake and a solid cam somewhere around the 250-260 degress at 50. maybe 550 lift. Will run behind a car weighing 3400 lbs with 4500 converter and 456 gears on 28-29 tire. Has a 750 dbl pumper carb. With the piston about 13 thou. down and a 38 head gasket it might be 10.1 comp.

[1980RS]

I'm sorry I don't know how to do pictures. Its a 2 bolt main block. The heads will probably be world products 200 cc int heads. 2.02 & 1.60 valves angle plug too. Looking to shifting around 6500 rpm. Super Victor intake and a solid cam somewhere around the 250-260 degress at 50. maybe 550 lift. Will run behind a car weighing 3400 lbs with 4500 converter and 456 gears on 28-29 tire. Has a 750 dbl pumper carb. With the piston about 13 thou. down and a 38 head gasket it might be 10.1 comp.

Here is what I ran with my SBC 358, .040 350, the car ran the best of 11.29@117

flat top 358 ARP bolts cast crank, PM rods 9.8:1 compression
Sportsman II home ported heads with 7/16" Roller Rockers and a stud girdle
Engle .600 lift cam, 250° duration@ .050 on a 108LCA
1 3/4 Super Comp headers but I think the 1 5/8 would be stronger
Holley 300-25 and a test with a 300-36 dual plane with the single being a touch better on the top
850 Might Demon
42°timing

[GARY C]

Will have a stock cast crank eagle rods and a set of OLD Lunati Taylor flat tops forged. Anything speacial about these pistons? I have had them stored for decades. They do not have wrist pins. I think there 2.97 7.50 pins will check. Will they take a 175 shot of nos?

Most of our early day 1/8 mile racing was stock cast crank, rods and cheap forged pistons with around 150 shot, never broke anything.

Ck with your ring mnf on end gap for nitrous.

EMC tv ran a stock 305 with nitrous and at 300 hp they butted the end gaps and broke a ring land.

[steve cowan]

I'm sorry I don't know how to do pictures. Its a 2 bolt main block. The heads will probably be world products 200 cc int heads. 2.02 & 1.60 valves angle plug too. Looking to shifting around 6500 rpm. Super Victor intake and a solid cam somewhere around the 250-260 degress at 50. maybe 550 lift. Will run behind a car weighing 3400 lbs with 4500 converter and 456 gears on 28-29 tire. Has a 750 dbl pumper carb. With the piston about 13 thou. down and a 38 head gasket it might be 10.1 comp.

Are the heads and intake manifold ported??
Be mindful of your finish line rpm as well with the nitrous, it will probably add around 1000rpm extra at the stripe.
Sportsman 2 heads and S/V can both work really well but need work,as cast the intake runner flows about 250cfm
The exhaust port is poor and suffers from the usual turbulence issues.
James(MELWAY) ran a 3400 pound car with a 358sbc with Sportsman 2 heads ran 9.8s NA.

[steve cowan]

I'm sorry I don't know how to do pictures. Its a 2 bolt main block. The heads will probably be world products 200 cc int heads. 2.02 & 1.60 valves angle plug too. Looking to shifting around 6500 rpm. Super Victor intake and a solid cam somewhere around the 250-260 degress at 50. maybe 550 lift. Will run behind a car weighing 3400 lbs with 4500 converter and 456 gears on 28-29 tire. Has a 750 dbl pumper carb. With the piston about 13 thou. down and a 38 head gasket it might be 10.1 comp.

Here is what I ran with my SBC 358, .040 350, the car ran the best of 11.29@117

flat top 358 ARP bolts cast crank, PM rods 9.8:1 compression
Sportsman II home ported heads with 7/16" Roller Rockers and a stud girdle
Engle .600 lift cam, 250° duration@ .050 on a 108LCA
1 3/4 Super Comp headers but I think the 1 5/8 would be stronger
Holley 300-25 and a test with a 300-36 dual plane with the single being a touch better on the top
850 Might Demon
42°timing

I think your engine run really good for the sum of parts used,I like the 300-25 intake,
Do you have access to a flow bench or are you very good at measuring with inside dividers to get your cross sections without a bench

[econo racer]

also have this cam new. Its a Bullett PT# S9892 solid 258 in 254exh 5.19 lift int and exh. 106 CL lash 15-17 any good? I see a 6400 rpm shift? I am filing top rings 27 and second ring 25 just in case I bolt a small B&M 144 blower with 7 lbs boost. I paid premium for these ancient parts years ago but want to use them the best I can.

[econo racer]

1980 RS that motor you put together looks like it would not be harsh on parts, possibly a good long life motor.

[Racer97]

Will have a stock cast crank eagle rods and a set of OLD Lunati Taylor flat tops forged. Anything speacial about these pistons? I have had them stored for decades. They do not have wrist pins. I think there 2.97 7.50 pins will check. Will they take a 175 shot of nos?

I ran a ho305 with a 250 shot years ago . It was stock with a victor me intake(it came on the car) stock manifolds fuel pump ect... About 30 street races and 50 passes at atco raceway .ran 12.50 all day . replaced the cam with a comp 280 ran about 10 more street races then back to the track and finally melted the number 2 cylinder piston on a 13.00 @ 70 mph . With the correct fuel pressure it would have lived alot longer . So add some ring gap and correct tune and you should be good with those pistons and gap the rings.

[1980RS]

I'm sorry I don't know how to do pictures. Its a 2 bolt main block. The heads will probably be world products 200 cc int heads. 2.02 & 1.60 valves angle plug too. Looking to shifting around 6500 rpm. Super Victor intake and a solid cam somewhere around the 250-260 degress at 50. maybe 550 lift. Will run behind a car weighing 3400 lbs with 4500 converter and 456 gears on 28-29 tire. Has a 750 dbl pumper carb. With the piston about 13 thou. down and a 38 head gasket it might be 10.1 comp.

Here is what I ran with my SBC 358, .040 350, the car ran the best of 11.29@117

flat top 358 ARP bolts cast crank, PM rods 9.8:1 compression
Sportsman II home ported heads with 7/16" Roller Rockers and a stud girdle
Engle .600 lift cam, 250° duration@ .050 on a 108LCA
1 3/4 Super Comp headers but I think the 1 5/8 would be stronger
Holley 300-25 and a test with a 300-36 dual plane with the single being a touch better on the top
850 Might Demon
42°timing

I think your engine run really good for the sum of parts used,I like the 300-25 intake,
Do you have access to a flow bench or are you very good at measuring with inside dividers to get your cross sections without a bench

I sure wish I had access to a flow bench. The closest and most affordable take like 3 weeks to get one heads done. I am still trying to figure out how to attach runner dividers without a tig welder. Some say you can use AB epxoy and just extend them out but I am not to comfortable with that.

[1980RS]

1980 RS that motor you put together looks like it would not be harsh on parts, possibly a good long life motor.

I have used the 358 since I put it together in 2007. One freshen up, started out in the mid-12's and so far has run in the low 11's. I think a set of Vortec would outshine the Sportsman II head I have on it now.

[steve cowan]

Here is what I ran with my SBC 358, .040 350, the car ran the best of 11.29@117

flat top 358 ARP bolts cast crank, PM rods 9.8:1 compression
Sportsman II home ported heads with 7/16" Roller Rockers and a stud girdle
Engle .600 lift cam, 250° duration@ .050 on a 108LCA
1 3/4 Super Comp headers but I think the 1 5/8 would be stronger
Holley 300-25 and a test with a 300-36 dual plane with the single being a touch better on the top
850 Might Demon
42°timing

I think your engine run really good for the sum of parts used,I like the 300-25 intake,
Do you have access to a flow bench or are you very good at measuring with inside dividers to get your cross sections without a bench

I sure wish I had access to a flow bench. The closest and most affordable take like 3 weeks to get one heads done. I am still trying to figure out how to attach runner dividers without a tig welder. Some say you can use AB epxoy and just extend them out but I am not to comfortable with that.

I just bought my first tig welder a couple of weeks ago for the same thing,I use epoxy in cylinder heads and intake manifolds but have never tried epoxy runner extenders.