[68Chevele]

After I test my PP 461 for the last time with the cam change I have a new project I am going to start. I call it Junk 400 test, I have an old stock bore 400 SBC sitting that has had a hard life but I think my test will be a real eye opener. The 400 has the following things done to it
Stock 4.125 bore
Stock Stroke 3.76
Stock 487X heads (80cc's)
268 Comp Cam (an older grind that works)
Performer RPM
1 5/8" headers
Will test 4 different 600 to 650 carburetors

My goal will be to to run the mild junk engine to get a base line then switch out the heads for my other set of Stock Vortec 906's that ran mid 11's last year. I will need to add some Moroso ceramic sealer as they have some tiny cracks and that stuff works. It will be fun to see what difference a 30 year old rebuilt engine can do with some new life.

 

[WHT/73]

Should be interesting! What are the pistons? Flat top, Didshed?
Stock 5.65 rods?
What's the planned compression?
You can use a shim to try to keep the compression closer to each other so we can see the net gain if at least the compression remains the same or close and the weather of course.

 

[68Chevele]

Should be interesting! What are the pistons? Flat top, Didshed?
Stock 5.65 rods?
What's the planned compression?
You can use a shim to try to keep the compression closer to each other so we can see the net gain if at least the compression remains the same or close and the weather of course.

Factory Dished pistons, 5.65 rods and the compression with the 487's is like 8.2 and with the Vortec's might be 9.5 and you are right the weather is always a player when It comes to performance.

 

[Dragginwagon467]

After I test my PP 461 for the last time with the cam change I have a new project I am going to start. I call it Junk 400 test, I have an old stock bore 400 SBC sitting that has had a hard life but I think my test will be a real eye opener. The 400 has the following things done to it
Stock 4.125 bore
Stock Stroke 3.76
Stock 487X heads (80cc's)
268 Comp Cam (an older grind that works)
Performer RPM
1 5/8" headers
Will test 4 different 600 to 650 carburetors

My goal will be to to run the mild junk engine to get a base line then switch out the heads for my other set of Stock Vortec 906's that ran mid 11's last year. I will need to add some Moroso ceramic sealer as they have some tiny cracks and that stuff works. It will be fun to see what difference a 30 year old rebuilt engine can do with some new life.

I’m a big fan of the Comp 268H cam, it delivers strong mid range torque. Using that in a 400 should make a true stump puller.

It’s a reasonavly small cam, it’ll be interesting to see how much hp it will show.

 

[wes migletz]

My son went [email protected] at Fontana with a 268 high energy cam in a worn out dish piston short block, with a set of Vortec heads that were ported by another forum member. It had a RPM air gap, 3.42 posi, stock TH350 and converter in a 68 Camaro.

It was a real nice driver.

 

[68Chevele]

My son went [email protected] at Fontana with a 268 high energy cam in a worn out dish piston short block, with a set of Vortec heads that were ported by another forum member. It had a RPM air gap, 3.42 posi, stock TH350 and converter in a 68 Camaro.

It was a real nice driver.

I am hoping out of the gate this old thing runs some 12.90's for a baseline. After all I have run 13.07 with a bone stock 350 Vortec SBC shifting at 4500 that day. The car had a bad alternator or it might have gone high 12's.

 

[WHT/73]

Factory Dished pistons, 5.65 rods and the compression with the 487's is like 8.2 and with the Vortec's might be 9.5 and you are right the weather is always a player when It comes to performance.

Oh ok. When it was rebuilt, it was just honed and re ringed,bearings and such? Almost 1.5 comp diff will help too. That's why I suggested a .015 shim HG to kind of keep compression close so it's an apple to apple deal. I used these on my 355 with my afr heads to bump compression and quench and went [email protected],114 in my nova with 3.73's depending on weather.

What's it going in? Combo of the car?
Just curious. I love these engines! So nothing would surprise me. IE; 441ci small block with twins going back in my car.

 

[68Chevele]

Oh ok. When it was rebuilt, it was just honed and re ringed,bearings and such? Almost 1.5 comp diff will help too. That's why I suggested a .015 shim HG to kind of keep compression close so it's an apple to apple deal. I used these on my 355 with my afr heads to bump compression and quench and went [email protected],114 in my nova with 3.73's depending on weather.

What's it going in? Combo of the car?
Just curious. I love these engines! So nothing would surprise me. IE; 441ci small block with twins going back in my car.

I don't think there is a steel shim head gasket for a 400 sbc, the engine was a budget re-ring way back in 1991 and all the miles are pretty hard on it but even the day I took it out of my Son's car it still ran great. It's going in a 2nd gen Camaro, turbo 400 4.10 geared car I run. I know one thing about this engine, I won't have to worry about hooking up with it as this one will make a lot less HP than the one I ran last year. Tried to sell it several times but not going to let a good 400 snc go for the $200 offers that I got for it.

 

[6426yy]

Speedway has a .022 shim gasket for the 400

 

[6426yy]

.024 Sorry

 

[WHT/73]

4.10's should still blow the tires off IMO. What's a 2nd gen weigh? 3500?

 

[68Chevele]

4.10's should still blow the tires off IMO. What's a 2nd gen weigh? 3500?

Last time I weighed it was back in the 90's it was like 3240 without me in it. I can get it done again as my Super Stock friend just gave his analog scales to someone I know that will weigh it for me this year and I will re-check it when I have the BBC in it also. I guess if I had my street tires on the car it might blow the tires off but not the 30X9's. I plan to video the whole project from start to finish. I am even going to test some Eddy carbs I modified for this test and I really don't like them at all.