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Bowtie
14-11-01, 06:01 PM
Hi all

I probably have to change my engine of choice from a Chevy 350 to a Chevy 305 (Swedish law). Below is a list of modifications I was planning for my 350. The scope is an engine that sounds like a real American V8, durable, cheap to buy and maintain, reasonable torque, easy to drive in city traffic and as low fuel consumption as possible.

I plan to do most of the job my self with some help from my father’s garage. We usually work with British and Italian cars so an American engine is a new experience, at least for me. I would therefor like to ask this forum about an opinion on my rebuild specification. Is it sane? Any suggestions for improvements (please keep my scope in mind)? The spec is made up for a 350 is it applicable for a 305 (using 305 parts)?

Last question, what is the chance that someone would spot a 350 stamped with a 305 engine number as the 350 it really is? :7

Thanks in advance for you opinions / Bowtie

Specification for my Chevy 350 rebuild:

[li]Block – stock 2 or 4 bolt mains, re-bore and block-deck if needed.
[li]Crank – stock, re-grind if needed.
[li]Bearings – stock or MM&S.
[li]Damper – stock or Vibratec Street Damper.
[li]Rods – stock or sportsman style from Lunati/Scat/Wheeler.
[li]Pistons – Silvolite “Claimer” pistons, Hypereutectic cast.
[li]Piston rings – stock budget ductile iron rebuilder.
[li]Balancing – none.
[li]Oil pump – stock.
[li]Oil pan – stock or Canton/Moroso.
[li]Oil filter – K&N paper element filter.
[li]Heads – World Products SR or Sportsman II.
[li]Head gasket – Steel 0.15-0.25 thick.
[li]Cams – overlap around 50, timing 2-4 degrees advanced, Lobe Centerline Angle - >= 108 degrees, duration to match RPM and maximized lift.
[li]Rockers – 1.6:1 Comp Cams Ball Pivot Stainless Magnum roller tip, bronze guides.
[li]Retainers – as light as possible.
[li]Keepers – stock.
[li]Lifters and rollers – Crane’s SR Roller Profile or Comp Cams equivalent.
[li]Push rods – stock quality 5/16 in or Chrome Molly.
[li]Air filtration – K&N.
[li]Carburetors – stock TBI later replaced with a replacement Holley 670 CFM 2-bbl TBI.
[li]Manifold – stock aluminum 4-barrel ported or Weiand Street Ram/Edelbrock Victor Jr/Weiand Team G/Holley 300-25.
[li]Headers – Walkers or custom made with primary pipes 1-5/8 in, secondary 2.5 in, pipe length spread 24-36 in, collector length 18-24 in.
[li]Exhaust – custom made under-slung with terminator box and mufflers by Walkers or FlowMasters, balanced pipes if possible.
[li]HEI - stock with Accel “Blue Print” rebuild unit.
[li]Coil – stock.
[li]Module – Nology.
[li]Cables – Accel Super Stock cables.

robert
15-11-01, 10:44 AM
>[li]Balancing – none.

Get it balanced, there is no point building a nice engine, and then for it to vibrate and cause problems later.

Robert
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Bowtie
15-11-01, 05:31 PM
The value of balancing could be discussed. It might be essential for a race tuned high reving engine. My specification is more like “most bang for the buck” and with a maximum RPM at around 6000. I am not so sure that a professional balancing job is really worth it on this kind of engine. I might balance what I can myself by hand but that will probably be it. But you are right, balancing is generally a good thing…

/ Bowtie

Purple Ronnie
15-11-01, 07:06 PM
I would recomend getting it ballanced. If you don't I think you would eventualy regret it.I started off going to fit a Rover V8 but ended up with a very expensive Chevy. When Ken Coleman of EDA explained all about the Chevy V8's and what machining work improves what on the road it was clear that I couldn't cut corners. Spend as much as you can on the engine, you won't regret it.

dave
15-11-01, 07:53 PM
>I would recomend getting it ballanced. If you don't I think you would
>eventualy regret it.I started off going to fit a Rover V8 but ended up
>with a very expensive Chevy. When Ken Coleman of EDA explained all
>about the Chevy V8's and what machining work improves what on the road
>it was clear that I couldn't cut corners. Spend as much as you can on
>the engine, you won't regret it.

but spend it at the right place...some engine tuners are bandits (not the one above though,he is highly recommended by a number of people on this site)

;-)

Purple Ronnie
16-11-01, 07:17 PM
Too true! If only we all had an excess amount of cash like Rob!:7

robert
16-11-01, 07:40 PM
>Too true! If only we all had an excess amount of cash like Rob!:7

Where, and if I have got an excess, don't tell Andy as he might want paying!!!

Robert
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RigMan
17-11-01, 08:57 PM
Errr.....ballancing is a must in any American V8 that you intend to use in anything but a lumbering pick up which won't see anything but lazy duty. American engineering standards for these engines was not brilliant and if you care to look at the numbers for forces/loads applied with increasing RPM, for every gram the rotating assembly is out off ballance you would be horrified. If you want performance and longevity out of the motor then it is a must that you perform the propper ballancing procedure at a good machinists. If you are also using old rods, it is also essential the you have them recircled, they often go out of round. Also upgrade to ARP bolts! Chrome moly rings are also a good investment as they bed in quicker!


RigMan:-)

Purple Ronnie
17-11-01, 08:57 PM
Do I get the impression that you've got another project under way?

Purple Ronnie
17-11-01, 09:00 PM
Sounds like this man knows what he's talking about.

robert
17-11-01, 09:28 PM
If I can get it past the wife, then yes.

Robert
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imported_admin
18-11-01, 08:13 AM
Sorry to sound a twat... but whats involved in 'balancing' an Engine? I'm going to go for a Chevy myself, but I'm going to get it pro-built as I think building such an important part should be done by someone who knows what their doing.

Cheers guy's

Sedge

mikey
18-11-01, 09:40 AM
Listen to the guys. Kenny Coleman balanced mine and the difference is significant. The engine didn,t seem rough before but Oh boy once its done the pick up characteristics and just the way the unit revs without any perceivable shake is much better. What is balancing? well it means an engine strip but if you're building one thats O.K. Basically the parts which put a load on the spinning crankshaft are weighed e.g. pistons,rods as they have to be similar. It is worth buying a decent set of rods (Eagle are a good budget brand) as they will come out of the box as a matched set near as damned it. Piston skirts can be relieved to achieve matching weight. The crank, flywheel and clutch are then balanced and tested as a complete unit in a balancing rig and that is similar in principle to the one used when you get your wheels balanced. Instead pf sticking on weights holes or part holes are drilled in the material to get the balance. If you are going to get balancing carried out I believe it is worth grinding off all the flash casting marks off the crank as this relieves stress points.BUT DO THIS BEFORE ITS BALANCED (unless you're called Robert who can afford a forged crank).
If you're getting it pro built check on the Pro, if he or she is a real pro they will carry the above out but make sure by specifying it. I dont know anybody any better than Kenny Coleman at Engine Data Unit in Castleford. He's not cheap but he's bloody good value even though he is a Yorkshireman like me.
Best of Luck.
Mike. :-) :-)