400 sbc performance rebuild
#1
400 sbc performance rebuild
Got 400 sbc, no price limit but don't want to go
Overboard, want best performance parts for cost
-run premium or regular, 10 to 1 or 10.5 to 1
- naturally aspirated
-taking suggestions for pistons, rods, aftermarket heads,
Intake, taking in consideration it has to fit under stock hood
Of 76 sting ray.
Would like to hear your ideas, thanks.
Overboard, want best performance parts for cost
-run premium or regular, 10 to 1 or 10.5 to 1
- naturally aspirated
-taking suggestions for pistons, rods, aftermarket heads,
Intake, taking in consideration it has to fit under stock hood
Of 76 sting ray.
Would like to hear your ideas, thanks.
#2
Melting Slicks
I have no idea but Im sure others will ask for more info...
What are your intended uses, rpm range, rear gears, transmission etc?
Need more info to help you decide.
What are your intended uses, rpm range, rear gears, transmission etc?
Need more info to help you decide.
#6
Safety Car
Easily done. Afr 195's and a hydraulic roller in the 268 to 270 advertised duration. Performer rpm. Desired Compression determined by camshaft selection. Easy 400 horse tons of torque.
#8
Burning Brakes
Member Since: Sep 2012
Location: coon rapids mn
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with AFR heads and a mild roller cam you will probably make 450+ hp,500 tq.check out competition products for a 400 rotating assembly ,and alumimin heads.you mite need a 2500-3000 rpm converter for a mild roller cam.pick the cam after you have determined you static compression.talk to a cam techican to get a street friendly dynamic compression.try to run cooling lines from the back of the intake to the water pump.
#9
Safety Car
Id say pick a camshaft bias on its rpm range, use a dynamic compression calculator to figure the dynamic, figure in .10 +/- of 8.0 and figure that, so if you use a camshaft that alows for 10 to 1 with all thats figured in to bring you to 8.0, 8.1, even 8.2 dynamic compression ratio with aluminum heads and the intake closing point and youve got that part nailed, take the rpm range of the camshaft and add 400 rpm for the stall converter ie, if the rpm range is from 2000 to 5500 rpm, pick a 2400 rpm stall. Remember that if you plan to use nitrous, or a super charger later that you might want to consider an antiballoning plate, cheaper converters are alot looser, you might also want to forged components for all applications as you dont usualy uconsider futer upgrades. With a 400 youll need 1.75" headers min. Lastly regaurdless of what you'll hear balance, balance, balance. Its the longevity regaurdless of rpm range. H beams are stout, but most i beams will handle 500 horse and most come forged, which are lighter weight and rev quiker. If you decide that you want a higher rpm range than about 6200 rpm youll need to change intake runner volume. Any thing past 6200 rpm you might want to up grade to at least ductile iron mains.
Last edited by bluedawg; 06-13-2013 at 01:44 AM.
#10
Safety Car
I know that this might help cool, but my shp 400 runs 180f no matter what with out the the cooling lines from back to the thermostat. Ive seen other 400 builds using them. Main thing about a stock block 400 is drill steam holes. Some build 400 with out steam holes, but some end up building and tearing down to drill stewm holes.
Last edited by bluedawg; 06-13-2013 at 01:46 AM.
#11
Pro
Not long ago finished assembling a 400 SBC - Have not had a chance to drop it in yet, but this is the combo I went with. One reason I've delayed the installation was to get my rear end squared away - I just finished that, so now I only have to find a free weekend to swap motors. My car is pretty much a driver - I am shooting for a fun engine to cruise with on the highway, but with plenty of low-to-mid range torque.
My (soon to be) setup:
400 with splayed mains
New rotating assembly; set up for 10:1 with 65cc heads
AFR 195 Heads
Crower 00468 cam
7104 RPM Performer intake
2400-2600 stall
I have a 700r4transmission in the car with 3:55 gears.
Cam recommendation came from 63Mako, based on my heads and stated goals - You might want to read up on other builds and ask some of the more experienced guys on this forum - incredibly helpful and tons of knowledge.
My (soon to be) setup:
400 with splayed mains
New rotating assembly; set up for 10:1 with 65cc heads
AFR 195 Heads
Crower 00468 cam
7104 RPM Performer intake
2400-2600 stall
I have a 700r4transmission in the car with 3:55 gears.
Cam recommendation came from 63Mako, based on my heads and stated goals - You might want to read up on other builds and ask some of the more experienced guys on this forum - incredibly helpful and tons of knowledge.
#12
Safety Car
I have a 406 sitting on the engine stand for about 5 years now, waiting for my 350 too blow but no luck yet
I used my crank, rods and the summit 9.62 compression rebuild kit. Basically Hypertec pistons with 4 valve reliefs but it was brought to my attention that these pistons sit down almost .020 in the cylinder at TDC.
My advise is measure this in your piston to deck clearance BEFORE you buy heads so you can order the correct cc chamber!
Camshaft for @10:1 compression I like to stay under .220 duration at .050
Mild 400 aren't screamers 5800-6000rpm with stock internals is about as high as you want too go
As you progress with the short block come back with pics and throw at what Cha got and I'm sure the guys will give you plenty of tips!
I used my crank, rods and the summit 9.62 compression rebuild kit. Basically Hypertec pistons with 4 valve reliefs but it was brought to my attention that these pistons sit down almost .020 in the cylinder at TDC.
My advise is measure this in your piston to deck clearance BEFORE you buy heads so you can order the correct cc chamber!
Camshaft for @10:1 compression I like to stay under .220 duration at .050
Mild 400 aren't screamers 5800-6000rpm with stock internals is about as high as you want too go
As you progress with the short block come back with pics and throw at what Cha got and I'm sure the guys will give you plenty of tips!
#13
Melting Slicks
Getting close or even breaking 400 horse and 500 lb/ft of torque from a mild 400/406 is pretty easy to do. A set of Vortec heads with a small roller cam and 9.5 to 1 will get you there. This is of course if you follow through with a good intake, carb, headers, exhaust pipes, etc...
Be careful with putting a lot of stall in the convertor with your 3.08 gears. You can create a condition with a lot of slip at highway speeds and have transmission heat problems. A build like above won't need much stall if any over stock.
Or you can go crazy and be stupid like me!
Last edited by v2racing; 06-13-2013 at 02:00 PM.
#16
Race Director
Member Since: Jan 2000
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2020 C2 of the Year - Modified Winner
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400 HP won't take any work at all. We did a 400" one using a Dart SHP shortblock with a set of out of the box Dart 200cc SHP heads. It had 11.0 compression and a streetable solid roller cam..but runs on pump gas just fine in a '61 Vette with a TKO.
It made 495 HP with a ported 2x4 intake off a 283/270 HP '61 Vette using two WCFB carbs. Then we installed a Dart dual plane intake with a Holley 750 Street HP carb..it made 540 HP. Next we installed a Weiand single plane with the same carb (actually much shorter than the dual plane) and made 555 HP!
With some good CNC heads or porting as cast ones the power would have gone even higher. The point is you can detune it some and still make 500 HP easily. Don't scrimp on the heads...that's where the power is. Vortecs are good..but they will run out of steam early as compared to many aftermarket ones.
JIM
It made 495 HP with a ported 2x4 intake off a 283/270 HP '61 Vette using two WCFB carbs. Then we installed a Dart dual plane intake with a Holley 750 Street HP carb..it made 540 HP. Next we installed a Weiand single plane with the same carb (actually much shorter than the dual plane) and made 555 HP!
With some good CNC heads or porting as cast ones the power would have gone even higher. The point is you can detune it some and still make 500 HP easily. Don't scrimp on the heads...that's where the power is. Vortecs are good..but they will run out of steam early as compared to many aftermarket ones.
JIM
#17
Finally started measuring cylinders and they all
We're just barely over 4.125, considered just honing
Them .010 over for the sake of time and money, good
Idea or send it to machine shop?
We're just barely over 4.125, considered just honing
Them .010 over for the sake of time and money, good
Idea or send it to machine shop?
#19
Safety Car
no... it varies and depends what was done before.... all you need is a feeler gauge set to measure it though... at least thats what I used... found my flat tops were .039 in the hole! (because of the model speed pro pistons used)