400 SBC- performance on a budget buildup --- opinions/experi

[Guest heinera]

I have aqcuired a 400 sbc and want to build a performance oriented motor with an eye toward value and bang for the buck. I have read the book by David Vizard about max perf SBC on a budget. I want to put the engine in my Z, but may also put it in something else later. I want an engine that will be reliable to 100K miles. I am interested in your thoughts on camshaft selection. Solid, hydraulic, hyd roller, solid roller, and specs. Here is what I am considering building so far. I would like 450-500 lb/ft torque, and 400+ horsepower. All at less than 5500 rpm- desktop dyno 2000 said its possible, but only with a roller cam...

 

 

400 SBC bored .030

either reworked stock crank, OR scat 9000 internal balance(ebay)

5.7" LT1 rods with ARP bolts(ebay), OR Scat/eagle rods 5.7(ebay)

Hyper dish pistons(ebay), about 9-9.5:1 static compression?

Vortec L31 heads, w/ mild exhaust blending/smoothing, drilled for 400 steam holes, reworked spring base, and lifter guide for higher lift.

RPM airgap intake port matched.

Miloden oil pan baffled

Quieter mufflers- I Don't want attention every time I stand on it.

 

Now the questions...

 

My main question is- in a torque and midrange HP motor is it of any benefit to use a roller camshaft? And how much benefit. Also does it matter if hydraulic or solid? And again, how much difference.

zero gap rings? worth it?

Carb? Demon, HP holley, holley double pumper, edelbrock AVS, etc? Do I need the more expensive carbs to make the power?

Roller rockers, worth it? Needed?

A guy on ebay sells directions for how to adapt an LT1 hyd roller camshaft and associated lifters, retainers etc into a pre 86 SBC. I think it involves drilling and tapping a few holes to mount the spider valley retainer thing. Anyone try this, and does it work?

 

Anyone with similar combo have any ideas or experiences.

[grumpyvette]

Now the questions...

 

My main question is- in a torque and midrange HP motor is it of any benefit to use a roller camshaft? And how much benefit. Also does it matter if hydraulic or solid? And again, how much difference.

 

first read this

http://www.idavette.net/hib/camcon.htm

then keep in mind that theres no real advantage to useing a solid

lifter because the engines stroke, the heads ax lift potential and port flow plus piston speeds all tend to keep the power peak under 5500rpm where the hydrolic lifters work with less maininance[/b]

 

zero gap rings? worth it?

 

Id say NO but its close

 

Carb? Demon, HP holley, holley double pumper, edelbrock AVS, etc? Do I need the more expensive carbs to make the power?

 

not really to make a set power level because most carbs can be moded to make good power but the better carbs are normally easier to tune and adjust and the tend to have a better mix

 

Roller rockers, worth it?

Id say the steel full rollers like crower or comp cams sell are wort it ON THE ENGINE YOUR PLANING

Needed? NOT REALLY BUT I THINK THEY WILL HELP

 

A guy on ebay sells directions for how to adapt an LT1 hyd roller camshaft and associated lifters, retainers etc into a pre 86 SBC. I think it involves drilling and tapping a few holes to mount the spider valley retainer thing. Anyone try this, and does it work? not that well, thats why chevy did not do it that way, the main problem is the pre-1987 non-roller block lifter bores are to short and lack support

 

Anyone with similar combo have any ideas or experiences.

 

yeah, carefully port the heads, do a good valve job,use good full length headers with a merge collector, a hydrolic roller cam and a windage screen with an 8 qt oil pan to insure good oil flow

 

look at this 350 build, built as a 406 with a similar roller cam,your almost sure to be 50 hp PLUS and 50 ftlbs PLUS higher

Displacement: 355 cu. in.

Carburetor: Demon Road Demon 625

Heads: GM L31 Vortecs, with 1.94/1.50 in. valves

Intake: Edelbrock Performer RPM Vortec

Camshaft: Comp Cams Xtreme Energy 268° hydraulic, with 268/280° of duration, 224/230° of duration @ 0.050 in. of lift and 0.477/0.480 in. of lift.(Corrected valve lift with 1.6:1 rockers is 0.508/0.512 in.)

Rockers: Comp Cams roller, 1.6:1

Headers: Hedman Elite 1 5/8 in.

Pistons: Speed Pro dished

Rods: stock

Crank: Scat

Distributor: Pertronix HEI

Timing: 36°

Comp. Ratio: 8.75:1

 

MAX HP: 390 @ 6000

MAX Torque: 426 @ 4000

 

_________________

 

heres a good matching hydrolic roller cam but you should be useing about a 2500 stall and 3.73 rear gears, and you MUST CLEARANCE THE HEADS/SPRINGS ETC. and use about 9.5:1 compression

 

http://dab7.cranecams.com/SpecCard/DisplayCatalogCard.asp?PN=119831&B1=Display+Card

[Guest heinera]

Thanks GrumpyV!

That is just what I was looking for.

If anyone else has an engine that is similar to what grumpy has suggested please let me know how it works, and what you might change. Below is what I am now planning

 

400 SBC .030 over

3.75 stroke

dished hyper pistons

vortec L31 heads- ported, cleaned up, moded to higher lift springs.

Hydraulic roller camshaft probably like what grumpy advised above, but maybe a little more mild, as I might put the engine in a larger car or 4x4 later.

large baffled oil pan

1 5/8" shorty headers (easy fit in the JTR position)- 2.5" to dual in 3" out muffler under/beside drivshaft to 3" muffler in back. (I want it to be quiet)

th200r4 tranny with RV shift kit, and 2000 or so convertor

[Len]

What do you estimate the rebuild will cost? With all those GOODIES? I may obtain a 400 SBC and had the same ideas.

[Guest heinera]

The costs... That is what I have been subconciously ignoring. Even though I call it a budget build it will cost a bunch. Here is the breakdown, but add more for misc this and thats.

 

used engine................................$200

 

machine work...all are estimated...

...clean..........................................$80

...magnuflux...................................$40

...bore/hone..................................$200

...if needed align hone....................$100.....I'll prob skip it

...polish crank................................$60.....maybe buy new crank

...press pistons...............................$30.... may use floater pistons

...balance rotating assembly............$150...may skip it and use OEM or slightly lighter weight pistons/rods

...rework heads .............................$200

Replace engine parts

...crank Scat 9000 int bal................$200 ebay

...Rods Scat 5.7"............................$150 ebay

...Pistons Sealed Power dished hyp..$160 ebay

...rings moly...................................$60 summit

...Vortec heads used.......................$300 ebay

...Camshaft Hyd roller.....................$150 ebay

...Hyd roller lifters..........................$150 ebay

...timing chain, cam button, etc........$50 ebay

...pushrods.....................................$20 ebay

...roller rockers...............................$150 ebay

...intake ........................................$150 ebay

...Carb...........................................$250 ebay

...distributor...................................$150 summit

...oil pump/pan...............................$130 summit

...gaskets.......................................$80 summit

...bolts...........................................$100 summit

 

What have I forgotten? Probably a bunch- but the total it already well above 2500

[Len]

Yea! I guess I was a bit sneaky along with wanting to know for myself. I figured it would be around the $2000 to $3000 range. But also didn't want to outright ask you if you thought of it. Now we both know .

Thanks

Hey maybe Santa for Christmas might give us a hand!

I always wanted to work a 400 SBC maybe not as hot as what your interested in. But would be neat to see what one could do with good rebuild & decient heads, cam etc.

Good Luck

[Chaparral2f]

You may want to check out Racingjunk.com I've bought a lot of stuff there, at some amazing prices

Joe