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HybridZ

interested in building a motor and have some questions


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alright well here goes, after sitting around for 5 days (got my wisdom teeth yanked) id done a bunch of research and talked to a few people about the motor in my Z its a recon rebuild chevy 350 the block is a 2 bolt main 3970010 and the heads are 333882s so here is my list of questions.

 

i did some research and found out that the heads on my motor are pretty darned restrictive. im interested in a budget build so id probably use iron heads... whats the best factory casting to start with that has accessory bolt holes?

 

since my Z is in running condition right now should i use this seasoned bored block as the basis for a new motor, or do i get an unbored seasoned block?

 

id like to do a 2 bolt main block so i can use the milodon splayed 4 bolt caps, this setup is stronger then the traditional factory 4 bolts correct?

 

my overrall goal for the motor is 400 hp without completely stressing all the parts in it IE: id like to build the motor so that i dont have to pin it to redline to make all that power, is this realistic with a budget built 350 ?

 

my last question is, who has published good books on building chevy motors, i see books at the speed shop all the time but what books do you guys prefer?

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The Vortec heads are a good budget Iron heads. I have them on my truck and like them. They require an intake manifold designed for them but that isn't too bad. They will need to be modified for a high lift cam which you will need for 400hp. As for the splayed four bolt main it is a nice piece but I'm not sure i would call it budget by the time you have them installed. I don't think you will need the splayed four bolt main for your requirements and that money would be better spent on a good set of aftermarket aluminum heads (Canfields/AFR's/Dart). In my area blocks are easy to come by and can be found with the factory four bolt mains (not a necessity IMO). I would get another block to build just for the reason that you can continue to drive your car while you build the new motor. Besides that you can then sell your current engine when you are done to help offset the cost of the parts.

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, after sitting around for 5 days (got my wisdom teeth yanked)

 

Awww sissy!When I had 4 wisdom teeth pulled, I was back at work the same afternoon....granted they sent me home because they couldn't stand to watch me spit blood every 2 minutes, but.... :D

 

I also have the Vortec heads on my truck and they are nice heads. I bought them with the stiffer springs and am runnung a L98 can grind. Unless you are going to running some very serious HP, the 2 bolt mains are fine. 400hp on two bolt mains is just fine. But you are correct, the splayed main caps on a 2 bolt block is stronger than a 4 bolt block, but overkill a bit. As for books...I love the Lingenfelter book the best!

 

Tim

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well as far as the wisdom teeth i went sledding the other night and hit a big jump the front of my sled dug in upon landing and i went head first into the snow over my back and onto my ass. then i realized i was spitting blood and that the moron stitched one of my gums to my cheek. anyways back to the chevys, i have a weiand single plane with the splitter thingy that i bought at a swap meet and put on my motor so that i could set my motor just low enough to clear with the big manifold. i know its way too big for what i have now, but it looks cool and itll make a great direct port manifold later on. anyways what did the l98 heads come in ? and whats a good price for a clean pair?

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the best deal for the money may be the vortec heads but it will depend on your goals.

 

http://www.chevyhiperformance.com/techarticles/41598/index4.html

 

http://www.chevyhiperformance.com/techarticles/41598/index5.html

 

http://www.chevyhiperformance.com/techarticles/41598/index6.html

 

 

now you might want to keep in mind that while airflow is not directly related to potential hp it is a good indication of potential

the vortecs can get about 430hp with some work they are limited in air flow potential compared to other options

here read this

 

vortec2.jpg

vortec3.jpg

 

http://sallee-chevrolet.com/Cylinder_Heads/Vortec.html

http://chevyhiperformance.com/howto/97458/

 

http://www.2quicknovas.com/vortecheads.html

 

 

http://www.babcox.com/editorial/us/us110128.htm

 

http://www.73-87.com/chp/gm3504.htm

 

http://www.babcox.com/editorial/ar/eb120121.htm

 

http://sallee-chevrolet.com/Cylinder_Heads/Vortec.html

 

http://64.90.9.168/cranecams/pdf/512e.pdf

 

http://www.summitracing.com/

CCA-982-KIT Chevrolet: 262-400, conical valve spring kit

 

http://www.streetrodstuff.com/Products/115/

 

http://www.carcraft.com/techarticles/116_0306_vort/index1.html

 

http://www.kendrick-auto.com/vortec_cs_gm_head.htm

 

 

(1) open throat to 85%-90% of valve size

(2)cut a 4 angle seat with 45 degree angle .065-.075 wide where the valve seats and about .100 at 60 degrees below and a .030 wide 30 degree cut above and a 20 degree cut above that rolled and blended into the combustion chamber

(3)blend the spark plug boss slightly and lay back the combustion chamber walls near the valves

(4)narrow but dont shorten the valve guide

(5) open and straiten and blend the upper two port corner edges along the port roof

(6) gasket match to/with intake and raise the port roof slightly

(7) back cut valves at 30 degrees

(8) polish valve face and round outer edges slightly

(9)polish combustion chamber surface and blend edges slightly

(10) remove and smooth away all casting flash , keep the floor of the port slightly rough but the roof and walls smoothed but not polished.

(11) use a head gasket to see the max you can open the combustion chamber walls

(12) blend but don,t grind away the short side radias

 

(13) have a local machine shop clearance the retainer to valve guide distance and add aftermarket springs and valve seals

(14) there are valve keepers available that add .050 extra clearance(USE THEM) but make sure the valve springs you use and the rocker/valve train geometry are set up correctly to work with the larger valve spring height and clearance!

(15) use the CORRECT matching rockers

(16) adding, machining for, screw in rocker studs is a good idea!

(17) your wasteing time and money runing a vortec head engine with an extreme high rpm cam,and intake, especially on a larger 383-427 displacement engine, the heads are designed to make massive torque in the 2000rpm-5500rpm range on a 350 displacement engine, they will not efficiently feed a 7000rpm combo on a larger engine so build your engine with that in mind

 

(18)if you intend to build a killer 383-427 sbc with vortec (STYLE) heads ID STRONGLY SUGGEST UPGRADING TO

 

E-Tec 200

Edelbrock E-Tec 200 heads have 200cc rectangular intake ports and 78cc exhaust ports. They outflow the “fast burn†aluminum heads by 10% on the intake and 17% on the exhaust, making power up to 6500 rpm. 64cc combustion chambers produce approximately 10.2:1 compression when used with flat-top pistons in 350-inch engines. E-Tec 200 heads come with 2.02" intake and 1.60" exhaust valves.

E-Tec 200

Chamber Size Bare (single) Complete (single)

64cc #60969* #60989*

 

heres a few things that you should read

 

http://www.zianet.com/v8monza/engine.htm

 

http://www.chevyhiperformance.com/techarticles/32458/

 

http://chevyhiperformance.com/techarticles/94138/

 

http://www.bracketmasters.com/small_block_stroker_383_cu.htm

 

http://www.gearheadracing.com/Reference/TorqueSpecChevy.htm

 

 

if you do nothing else buy and read these books BEFORE starting the engine build, and buy ,or borrow a quality engine stand I will save you hours of wasted effort,make the engine assembly far easier,SAVE THOUSANDS OF DOLLARS WASTED and YEARS OF LEARN TIME

check list

if theres any one tool you need its a good engine stand

stand info

you don,t need anywhere near a full selection of tools but be very carefull checking clearances and I highly advise buying a damper installation tool

IF THERES ONE RULE YOU MUST NEVER IGNORE ITS CHECK ALL CLEARANCES TWICE AND MAKE DAMN SURE THAT YOU UNDERSTAND WHAT THEY SHOULD BE AND WHY

 

 

 

71061744.jpg

 

 

 

 

http://www.73-87.com/chp/chp.htm

 

http://chevyhiperformance.com/techarticles/71298/index.html

 

http://www.sa-motorsports.com/diyport.htm

 

http://www.ryanscarpage.50megs.com/combos1.html

 

 

DO YOURSELF A HUGE FAVOR

buy these books, FIRST it will be the best money you ever spent, read them, and you will be miles ahead of the average guy. youll save thousands of dollars and thousands of hours once youve got a good basic understanding of what your trying to do!

 

HOW TO BUILD THE SMALL BLOCK CHEVEROLET by LARRY ATHERTON&LARRY SCHREIB

.

HOW TO BUILD MAX PERFORMANCE CHEVY SMALL BLOCKS ON A BUDGET by DAVID VIZARD

1884089348.01._PE30_PIdp-schmoo2,TopRight,7,-26_SCMZZZZZZZ_.jpg

.

JOHN LINGENFELTER on modifying small-block chevy engines

155788238X.01.TZZZZZZZ.jpg

how to build & modify CHEVROLET small-block V-8 CAMSHAFTS & VALVTRAINS BY DAVID VIZARD

 

SMOKEY YUNICK,S POWER SECRETS

0931472067.jpg

SMALL BLOCK CHEVY ENGINE BUILDUPS

1557884005.jpg

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well as far as the wisdom teeth i went sledding the other night and hit a big jump the front of my sled dug in upon landing and i went head first into the snow over my back and onto my ass. then i realized i was spitting blood and that the moron stitched one of my gums to my cheek. anyways back to the chevys, i have a weiand single plane with the splitter thingy that i bought at a swap meet and put on my motor so that i could set my motor just low enough to clear with the big manifold. i know its way too big for what i have now, but it looks cool and itll make a great direct port manifold later on. anyways what did the l98 heads come in ? and whats a good price for a clean pair?

 

L98 heads were availble on the 87-92 camaros(cast), and the aluminum heads where on the vettes.

 

You can see a complete write up on porting them here:

 

http://www.thirdgen.org/techbb2/showthread.php?s=&threadid=183264&highlight=L98+iron+head+project

 

 

Flow numbers listed in that article are:

 

.1 82.5 52.5

.2 145.6 111.8

.3 212.9 150.1

.4 245.4 178.6

.5 269.2 190.9

.6 270.6 195.2

 

Not too damn bad for a cheap set of heads. Enough for 400+hp

 

Phyte

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Guest woodyhooten

sounds like a cool project, let me know how it goes and that might be on the list of things to do for my swap

 

the stitches are supposed to be on the gums and the cheek because the incision they have to make is pretty big. Your dentist did it right, don't worry.

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sounds like a cool project' date=' let me know how it goes and that might be on the list of things to do for my swap

 

the stitches are supposed to be on the gums and the cheek because the incision they have to make is pretty big. Your dentist did it right, don't worry.[/quote']

 

ahhh alright that makes sense, those l98 heads are CHEAP, i like cheap :) now all i need is money time and money and time

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