Thread: bbc help

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i am buliding a 555 big block and i am in need of some advice on parts pistons,crank,rods,cam,head,intake. i know the specs on bore and stroke but i dont know what type of pistion what legth of rod and how to match up the cam and heads and intake.just let me know what info you need and i will give you all i know.to start its a 427 tall deck. thanks for the help.
david

yep....... tell me what RPM you want to see most of the time? is there going to be any low speed driving?? what fuel you want to use ??? any blower? Nos ? how much HP you think you need to see? be realistic there s going to be trade off s with more HP you need as well as $$ parts need to be of a better quality.then send me your parts two shoe boxs $100 dollar bills and you will get back a intake to oil pan tall deck BBC engine. i would not wast to much time building a tall deck 427 out to 555 .way to much money. there two block s with two PC rear main seal blocks that gm made the late one may take the 4.750 ??? would not bet on it the last one i did i re work it for a 4.500 crank. to 555 .4.310 bore x 4.750 crank .your going to hit water? less you go sbc rod size .much better is a 526 . all the work and money find a used 10.200 deck block World .Dart .Bowtie .etc. bore it to 4.600 x 4.7500 and be 632 cid be done with it

its gonna be in a 1970 chevy c10 long bed its gonna be mostly just cruzin the streets and very little track time like the last friday of every month from march to october at roxboro track for freaky friday and that will be just for fun with some friends. im gonna run 93 octane and i am eventally put a blower on it.as for rpm no more than 6000 if that. i help a couple of buddys with promods and i have a 383 in the truck right now so i know im not gonna get 1200 hp on pump gas and run on the street and run 4s at the track for 3000 bucks.and i was going with a 4.56 bore and a 4.25 crank but the rods is where i need help with making up for the .400 longer piston im pullin out for a standard piston and the block was givin to me so i really wont to use it. thanks

you are not going to bore a stock gm 427 tall deck to 4.560 the wall s are not that thick

For a street crzer in a pickup you can get more tire smoking power than you can hook up at just a .030 over stock stroke--you can use a .400 long rod and stock ch selvf pistons and make over 800 hp with maybe just a touch of no2

I ran 8.003 at 175 with a similar(in some aspects) engine in the Monza in my avator

In fact the pic was leaving the line on one of those runs

@ mccarthy i dint mean to look like a know it all some guy at the drag strip told me that he used his 427 tall for a 555 and bored to 4.560 do thank you for correting me.

@ clayton could you tell more of the specs on the motor your are talking about. not the one in your pic though i dont think i have the money for that

Originally Posted by bigd1970

@ mccarthy i dint mean to look like a know it all some guy at the drag strip told me that he used his 427 tall for a 555 and bored to 4.560 do thank you

well i did not want to either .. but i have built and machine BBC stuff for a income over the years .i have fixed stuff many may run a way from so i know abit how thick some blocks are

ive thoght about it and since my 555 idea is done for i reckon imma bulid a 496

I would also welcome any input from Pat or Jerry or anyone else who wants to critique these combinations. I just did these to show that you really can make big power for cheap with a BBC tall deck block.

Cheapo BBC 505 tall deck grunt motor

I'm always interested in researching street/strip combinations that are easy on the budget. This is a combo based on the tall deck 427T block. The block deck height of this block is 10.200", 0.400" taller than a regular production 396/427/454 block. The total combined stack measurement of parts I've used here is 10.185", leaving 0.015" nominal piston deck height on a virgin block. I'd check the decks for being square with the centerline of the main bearing bore and if they were, I might leave them alone and use a gasket such as 0.041" compressed thickness for a squish of 0.056". You can put this same motor together using a standard production 427 or 454 block, you just use 6.135" rods instead of the 6.535" rods used in this build and forget about the spacer plates.
http://www.summitracing.com/parts/FPP-1071/
Scat cast steel 4.250" crank....
http://www.summitracing.com/parts/SCA-945420/
Eagle 6.535" rods....
http://www.jegs.com/i/Eagle/356/CRS65353D/10002/-1
TRW H112CP+.100 hypereutectic pistons...
http://www.flatlanderracing.com/trwchevyspecial.html
Read across the chart for effective static compression ratios with different chamber volumes....

This makes a 505 in a tall deck block for cheap.

Continuing with relatively cheap....
Racing Head Service cast iron heads, 119cc chambers for 10.2:1 static compression ratio....
http://www.summitracing.com/parts/RHS-11301-02/
Published head flow factored by 0.90...
.100 68 56
.200 149 106
.300 221 144
.400 278 176
.500 306 206
.600 324 223
.700 338 239

Use these Moroso rectangular port spacer plates between heads and intake manifold, using Edelbrock #7202 intake gaskets on each side of the plates....
http://www.summitracing.com/parts/MOR-65090/

Edelbrock RPM intake for rectangular ports...
http://www.summitracing.com/parts/EDL-7163/

Or this RPM Air Gap for rectangular ports....
http://www.summitracing.com/parts/EDL-7562/

Or this Weiand Stealth for rectangular ports....
http://www.summitracing.com/parts/WND-8018/

The following DynoSim pulls were made with large-tube, equal-length headers through mufflers and an 850 carb....

More than one professional engine builder has advised that big block Chevies eat flat tappet camshafts, so be aware. I have composed three different pulls, with the only changes being the cam. One hydraulic flat tappet, one hydraulic retro-fit roller tappet and one solid flat tappet combination. I didn't build these to be race motors, but rather low-buck street/strip grunt motor combinations that nose over at 5500. I went through about half a dozen cams on each combination and am publishing the best results here.

I'll run the retro-hydraulic roller motor first. I used 1.8 rockers with it for a new lift of .552"/.572"...
CompCams XR288HR, part number 11-433-8
http://www.summitracing.com/parts/CCA-11-433-8/
RPM HP TQ
2000 193 508
2500 245 515
3000 311 544
3500 386 579
4000 455 600
4500 508 593
5000 546 573
5500 555 530
6000 490 429
Peak volumetric efficiency 97.6% @5000
Peak BMEP 178.2 @4000

This combo uses a hydraulic flat tappet cam with stock 1.7 rockers...There are those on this board who will advise against using a flat tappet camshaft in a BBC, including the author.
CompCams XE284H, part number 11-250-3
http://www.summitracing.com/parts/CCA-11-250-3/
RPM HP TQ
2000 195 512
2500 247 519
3000 314 550
3500 394 591
4000 470 617
4500 533 622
5000 581 611
5500 600 570
6000 589 516
Peak volumetric efficiency 100.9% @5000
Peak BMEP 185.6 @4500

Now here's one for those of you who don't mind checking valve lash maybe twice a year, although you could probably stretch it to yearly with the technology used today. Back in the day, this used to be a frequent chore, but not so much today. See, the thing is that once you get the lash set properly with the motor hot, you allow it to cool and check where the lash is. Then you can set it cold from then on and encounter no muss or fuss.
CompCams 288CR-8, part number 11-713-9
http://www.summitracing.com/parts/CCA-11-713-9/
Used stock 1.7 rockers. You'll need more spring in the heads to run this cam. Cylinder head part number I listed above has max lift of 0.600". This cam has 0.714" lift.
RPM HP TQ
2000 192 503
2500 246 517
3000 314 551
3500 403 605
4000 492 646
4500 573 670
5000 635 667
5500 673 642
6000 680 597
6500 659 533
Peak volumetric efficiency 98.3% @5000
Peak BMEP 199.7 @4500

to techinspector1 would i have to run diffrent pistons if i ran a blower and nitrious.

Originally Posted by bigd1970

to techinspector1 would i have to run diffrent pistons if i ran a blower and nitrious.

Yeah, Pat and Jerry have built more of those than I have, but you should probably start with 119cc heads and flat-top forged pistons.

... I have a tall deck bowtie block bored 4.5" assembled but never cranked up for sale... I could get you the specs on everything I put in it, for you to build or sell you the kit and kabootle...

vstech i would like to see the specs on the motor and parts if you wouldnt mind