can this make 520 hp?

[DCal]

Getting older and don't need my big block torque and horsepower any more and I wanted to build one last SBC so I'm needing some guidance. I would like to drop 200hp and whatever torque comes with that. That means about 520 hp

My combo so far is what I have ready to assemble but the short block can't change;
Dart SHP at 4.125 bore
CP pistons at 10.5 ;1, rings are 1mm, 1,5mm and 3mm
Carrillo 5.850 rods
Lunati 43# 3.750 stroke
Brodix track1 with M2 program. 2.080, 1.600 T&D shaft system with 1.5 rockers
heads flow 312 @ .600 lift, head int.port is 223cc
Mike Jones HR 233/236 @ .050, 109 in at 105, .585 lift
Intake is Air Gap ported to 1206 gasket. Also a Vic jr will be dyno'd
carbs go from 750vs to 950 but I'm banking on my HP950( actually 830 cfm)

I know that you don't need the manufacturers names but I called in a lot of favors and I really appreciate them.
So am I close? looking for a zesty motor but decent street manners. Thanks in advance.

[GOSFAST]

Getting older and don't need my big block torque and horsepower any more and I wanted to build one last SBC so I'm needing some guidance. I would like to drop 200hp and whatever torque comes with that. That means about 520 hp

My combo so far is what I have ready to assemble but the short block can't change;
Dart SHP at 4.125 bore
CP pistons at 10.5 ;1, rings are 1mm, 1,5mm and 3mm
Carrillo 5.850 rods
Lunati 43# 3.750 stroke
Brodix track1 with M2 program. 2.080, 1.600 T&D shaft system with 1.5 rockers
heads flow 312 @ .600 lift, head int.port is 223cc
Mike Jones HR 233/236 @ .050, 109 in at 105, .585 lift
Intake is Air Gap ported to 1206 gasket. Also a Vic jr will be dyno'd
carbs go from 750vs to 950 but I'm banking on my HP950( actually 830 cfm)

I know that you don't need the manufacturers names but I called in a lot of favors and I really appreciate them.
So am I close? looking for a zesty motor but decent street manners. Thanks in advance.

Hi Dave, you'll do that number with one plug wire off??

I would maybe pick another cam with slightly different numbers (a bit larger). We're seeing 600+ on a similar (pump-gas) platform!

Thanks, Gary in N.Y.

P.S. Not sure you remember me but we spoke about my friends '56 Chevy (Dragweek ride) a few years back when you were still working. He's up around 3000 HP now with the same brand pistons. With your help and theirs you all solved a major piston issue for us at the time and they are still helping today!!

[KnightEngines]

Pop some taller ratio intake rockers on it & let it eat.
You'll get there no probs, nice streetable combo.

[DCal]

Big difference in what Glen calls streetable and what I need LOL. 3000 hp is insane. We ground the cam a little small mainly because I kept losing focus on my goals and toward the end I tried to calm it down a little. I have plenty deep valve pockets so I can change the cam later. Thanks for giving me the benefit of your opinion Gary.

[cgarb]

What does CamKing say? He is usually very close in his estimates. Its a great engine with way more potential. If you want more power down the road you have all the right stuff already in place. If you only wanted to make 520 you should have built a 355 with those kind of parts. Should be a fun street engine for sure, mild but powerful.

[CamKing]

Mike Jones HR 233/236 @ .050, 109 in at 105, .585 lift

That doesn't look like any Hydr roller cam of mine. .585" Valve Lift, with 1.5 rockers would be .390" Lobe Lift. I don't have any .390" lobe lift HR profiles, under 250@.050"

[kimosabi]

I don't know if it will make 520 but it will most probably be a GREAT overall street engine. My build is very similar but a bit milder with a Mikes .360 lobe, hyd roller 232/232 on AFR 210 heads and 6" rods. Apart from that it's the same engine I built.

I run 8.0 sec 1/8 mile with it with over 2 sec 60ft from footbraking and on a shitty track it spins the tires all the way through all three gears. Good track it only spins first & 2nd. Stock interior 70 Camaro, 3600lb or so, 3.42 gears.

Torque from idle. Very driveable. Over 3000rpm on the highway for longer periods was NO PROBLEM for that valvetrain.

[cpmotors]

Easily.
This was a pretty mild 388ci to make 520hp.

[DCal]

Mike Jones HR 233/236 @ .050, 109 in at 105, .585 lift

That doesn't look like any Hydr roller cam of mine. .585" Valve Lift, with 1.5 rockers would be .390" Lobe Lift. I don't have any .390" lobe lift HR profiles, under 250@.050"

In Mike's defense I brought down a 20 year old Axtell hydraulic roller cam that I thought was too big for my converter etc. and he reground that cam for me leaving a nice base circle and a .389 lobe, .583 lift. I have the cam card ( # HR73389-75375)and my notes. So I'm happy with what he did and I want something different I'll call Mike again.

[DCal]

Easily.
This was a pretty mild 388ci to make 520hp.

Thanks Peter-I'm encouraged now. Did you modify the plenum divider or try any carb spacers?

[cpmotors]

Easily.
This was a pretty mild 388ci to make 520hp.

Thanks Peter-I'm encouraged now. Did you modify the plenum divider or try any carb spacers?

Intake is bone stock, not even a port match as the heads are a 1206 gasket and the intake is smaller upstream, so I didn't see any benefit for what the customer needed. 1" open spacer is pretty much standard, not that it is generally a big power increase but heat insulation and plenum volume seems to help even things out. Power goes up a bit, but don't remember exact numbers as it's usually maybe 5-8hp.

[SchmidtMotorWorks]

Are you starting from scratch or using parts you have?

If you are starting from scratch, using a Gen 1 SBC seems like an expensive and troublesome way to go vs an LS[X].

[DCal]

Are you starting from scratch or using parts you have?

If you are starting from scratch, using a Gen 1 SBC seems like an expensive and troublesome way tbut Io go vs an LS[X].

I Started from scratch, I got rid of everything SBC when I moved. I have a 68 Camaro so this should be Plug-n-Play with no fabrication or wiring mods and I'll have a real nice complete 565 BBC for sale in the future to help offset the cost of the new motor. I know the LS is popular but I went with what I was more familiar with.

[CamKing]

That doesn't look like any Hydr roller cam of mine. .585" Valve Lift, with 1.5 rockers would be .390" Lobe Lift. I don't have any .390" lobe lift HR profiles, under 250@.050"

In Mike's defense I brought down a 20 year old Axtell hydraulic roller cam that I thought was too big for my converter etc. and he reground that cam for me leaving a nice base circle and a .389 lobe, .583 lift. I have the cam card ( # HR73389-75375)and my notes.

OK. .583"/.562" Valve lift. That makes sense.
Should make over 520hp @ 6,200rpm.

[DCal]

Apparently it can. It made 553hp and 531tq. The small cam seemed to be the limiting factor as expected, but should provide the vacuum I need along with the Air Gap and 780vs 3310 and be a nice street engine. Thanks to everyone who helped with advice.