700+hp sbc 23 degree heads

[rookie]

Chad,
What is the largest intake valve it will handle and what rockers are needed?

[lun40119]

I had to go in some of your threads and you didn't post the sheets to see what the power was. I did find where you stated you guys were at 1.8hp per cubic inch. You said it is a 402 small block so this would be 723.6 horsepower before you and Tom started gaining horsepower. I know Butch said your transmission is a low drag unit but I'm not sure so maybe you could clarify this because he said you have a Turbo 350 and I thought for that power you would have either a Turbo 400 or a two speed Glide.

I do agree you are not showing the horsepower on the track but I don't see how leaving at a higher rpm will help at all. I know you said your stall converter was very high rpm and you were leaving at 2,200RPM. The rpm your at off the line is simply the staging rpm and if the engine will respond with no hesitation when you floor it wide open it is very possible to turn faster times from the lower stage rpm. This is because if the stall converter is a 5500RPM no matter what the rpm is on the transmission brake the engine will flash to that 5500RPM when you release the transmission brake and the same is true with the lower rpm launch from the transmission brake and foot brake. If the engine will respond from the lower rpm without hesitation it will hit the tires and suspension harder. The way this was explained to me by your buddy Butch when I had a converter issue and the converter company I use confirmed his analogy was perfect. I will just copy and past his e-mail to me so you can see it and if your lucky you can understand it because he had to explain it to me on the phone. I was lost

Shane, the problem with your converter is your staging rpms too low and dont foot brake that thing ever. The stall is say 6200rpm like mine, if you foot brake leave at 2500rpm that is your staging rpm so if you can whack it wide open at 2500rpm with no hesitation it will flash the converter to 6200rpm and if you were to stage at 4500rpm its still gonna flash at 6200rpm, that rpm is just your stage rpm and off the brake the same way thus your traction issues are from the rpm, lets say you stage at 2500rpm and whack it wide open, the rpms have a running hit on the converter thus nailing the rear tires and suspension, where if you stage at 5800rpm you dont have the running hit but still flash 6200rpm, so think if the 2500rpm launchh as a running punch at a guy and your 5800rpm launch as a punch standing in front of him with no running start

I saw Jake run at Tulsa after they drove from the other tracks in Dragweek . I don't think you can compare a footbraked, 3700 lb., smallblock Chevelle to a transbrake Mustang. I doubt the coinverter in Jake's car will flash over 5500 and i don't think he has a lightweight T-350, but i could be wrong. For most of Dragweek he had worn out tires and only got good, bias ply, slicks at Tulsa. The air was good but not ATCO good. I think a good set of Hoosier Radial slicks would probably pick up a tenth or so from the 10.19 he ran here. So maybe there is a little left in the weather, little left in traction and a little left in the perfect converter, not to mention the Chevelle is not very aerodynamic. Put Jake's engine in a 3150 lb. Mustang or Camaro and it would probably go 9.60s-9.70s on most days.

Harold.........there really is no reason to respond to these two gents. Both are internet bench racers that really don't understand. Armed with there Wallace Racing Calculator, they start numerous fights on every board they find. Butch was actually banned from this board after a couple years of bullshit!!! I'm pretty sure you are aware that he was also banned at Team Chevelle for his same antics. Neither of these two gents will ever bring their stuff out, to let the whole world have a look. It is much easier to hide behind a computer screen and poke fun of everyone elses combo.

Ive got a set of radial slicks we will be trying shortly, along with some other changes. Ill report Shane's post to Don........they banned Butch for a reason. If he is posting through other people, that person should have their posting privilege revoked as well.

Keep your eyes open for the Jan. 12 issue of Hotrod Mag Harold........David Frieburger did a feature on the car and it will be in that magazine.

As I said before, it was an absolute pleasure to meet you there.......your knowledge of these A-body's is amazing. Thanks for taking the time to stop and chit chat.........sorry I was so busy, I didn't get more time to talk.

Take care.

PS. Here is a cool video of the car that the HotRod staff put together. Makes me proud.....
http://www.youtube.com/watch?v=skLbhe2CBAU

[900HP]

Chad, that's a really nice looking cnc program. The chambers are real nice. I see the valve guide trailing edge on the intake and that is very nicely done, I'm confused by the exhaust port though. Maybe its just the light reflection but there appears to be a step cut cross-ways where the valve guide will be? Or is the exhaust port not finished yet and that's all guide boss?

[user-9274568]

Chad,
What is the largest intake valve it will handle and what rockers are needed?

It was designed around a 2.08, but you can use a 2.100 as well. I wouldn't go bigger, not enough cross section for any benefit.

I had a customer use a set of wide body Comp SS rockers and he was able to get a 3/8 pushrod in it. You will have a hard time with a 3/8 with some of the cheaper aluminum rockers. You need a wide body or a .080 offset Probe shaft will clear a 3/8.

[user-9274568]

Chad, that's a really nice looking cnc program. The chambers are real nice. I see the valve guide trailing edge on the intake and that is very nicely done, I'm confused by the exhaust port though. Maybe its just the light reflection but there appears to be a step cut cross-ways where the valve guide will be? Or is the exhaust port not finished yet and that's all guide boss?

Long story short, the first cores will need to be hand finished on the exhaust. I'm having the CNC core box modified so that the exhaust port will be shrunk .100 for full clean up. I had the port digitzed and ran just to see where it stood.

So yes, a little clean up required.

Here is the exit.

[900HP]

Gotcha! That kind of what I was thinking there. Nice looking heads there, I might just have to have a pair if I can talk someone into building a real hot 23* small block.

[user-9274568]

Gotcha! That kind of what I was thinking there. Nice looking heads there, I might just have to have a pair if I can talk someone into building a real hot 23* small block.

I have many options like a 2.08/2.100 valve, 5/16 or 8mm, 11/32 valves, 72-63cc chambers...

[mdross1]

Gotcha! That kind of what I was thinking there. Nice looking heads there, I might just have to have a pair if I can talk someone into building a real hot 23* small block.

You got my attention,all I need is a good set of 23*s that will get me what I'm after.The more I look the more choices I find.Need a set that will feed at least a 427" all it needs.

[user-9274568]

Gotcha! That kind of what I was thinking there. Nice looking heads there, I might just have to have a pair if I can talk someone into building a real hot 23* small block.

You got my attention,all I need is a good set of 23*s that will get me what I'm after.The more I look the more choices I find.Need a set that will feed at least a 427" all it needs.

This will feed a 427" SBC. 2.72in² at the pinch, standard rockers, 345cfm w/2.100 valve.

[Orr89rocz]

^^ i have a pair of those for my 401" twin turbo street motor Just assembling now but the heads look awesome and I will dyno it n/a first to get the intial tune down and then add my 70mm twins. Should be a wicked pump gas fun car

[mdross1]

Gotcha! That kind of what I was thinking there. Nice looking heads there, I might just have to have a pair if I can talk someone into building a real hot 23* small block.

You got my attention,all I need is a good set of 23*s that will get me what I'm after.The more I look the more choices I find.Need a set that will feed at least a 427" all it needs.

This will feed a 427" SBC. 2.72in² at the pinch, standard rockers, 345cfm w/2.100 valve.

Been away from it too long I guess.Always was led to believe that a port will only flow what is let through the seat,and was taught the 85% rule.Make the seat opening at least 85% of the valve diameter,always figured that the pinch area was not a big deal.Obviously I do not play with a flow bench,sure would like to! Honestly the flow numbers are interesting and I will always enjoy talking about technical side,bottom line is I need a topend that will give me the big number or very close to it and on street gas.Because this motor will be in a motorcycle torque is not a big deal.Will insist on instant throttle response don't we all.

[user-9274568]

Been away from it too long I guess.Always was led to believe that a port will only flow what is let through the seat,and was taught the 85% rule.Make the seat opening at least 85% of the valve diameter,always figured that the pinch area was not a big deal.Obviously I do not play with a flow bench,sure would like to! Honestly the flow numbers are interesting and I will always enjoy talking about technical side,bottom line is I need a topend that will give me the big number or very close to it and on street gas.Because this motor will be in a motorcycle torque is not a big deal.Will insist on instant throttle response don't we all.

Yea, you've been away too long! The port will only flow what is let through the minimum CSA, wherever that might be. I agree, it should be the seat ring. A 85% seat is really small. Even my street heads are 90%+..

[CamKing]

This will feed a 427" SBC. 2.72in² at the pinch, standard rockers, 345cfm w/2.100 valve.

Chad, can you send me a flow sheet on these?
I'm always getting customers that are building big inch SBC's, but want to stick with a 23deg head.

[user-9274568]

This will feed a 427" SBC. 2.72in² at the pinch, standard rockers, 345cfm w/2.100 valve.

Chad, can you send me a flow sheet on these?
I'm always getting customers that are building big inch SBC's, but want to stick with a 23deg head.

Here is a pdf of a set I just did last week. Just a valve job and a little blending.

http://www.speierracingheads.com/v2.72_flow.pdf

[CamKing]

Thanks, I just stapled it to the wall, above my desk.