New engine build advice

[aahx2011]

Some of you may have read my previous thread that my most recent engine build was not successful. Well since this is a do over I am sending another block to the machine shop, it is already a thirty over bore I really hope it can just be honed do not want to bore it as I have heard there can be issues with boring a block to much, cooling issues mostly. Anyways to the point I am putting this in a 1979 Chevrolet 4 wheel drive, automatic 350 turbo transmission, 3:73 gears, gm axles for now will up grade later. My last engine set up was almost all top end very little low end unless it was in 4 low. I want to increase the low end torque on this motor looking at using a comp cam part number 12-249-3 here is a link to the specs 12-239-3 - Xtreme 4 x 4, I already have the cam that is part of the reason for the use, so I would like to build the rest around the cam if possible. I would like to get some suggestions on build options and other products to build with so that I can get this one right.

[jerry clayton]

you previously said you put the cam in retarded 2 degrees for low end----------for low end you need to advance it---when the smog shit started in 72? cams were retarded 8 degrees in the ford 429/460s and they lost between 20 and 40 lbs tq at low speeds-------------


Oil pressure--------do you have the plug in the gallery going up from the oil pump that directs the oil thru the filter????? what distributor are you using??/ does it fit in the hole that intersects the right side lifter galley tight enough to seal the oil flow there---what pushrods/rockers flowed oil and what ones didn't?? was it side to side ??
do you have the front plugs in the oil galleys?????????how much clearance between pump piclup and oil pan bottom??????too much/too little are severe problems


High volume pumps aren't a big problem at slow speeds as pil will still be bypassed at the pump relief that is excess of the clearances amount---at high speeds it can pump too much upstairs more than can drain back in time to keep pan level good


do you have correct head and manifold gaskets installed properly ----early blocks/heads need water flow from block to heads at the rear not front----------


with th stat out take top hose off radiator and back fill engine until water comes out top of rad and then put hose on=== you can take a short belt on the water pump and use an electric drill to turn the pump to see if waterflows----also you can use industrial/marine see tru hose on the heater bupass nipple to determine same----


also----where do you have the temp sensor?????????? do you have Teflon sealer or tape on the threads???? has the water boiled or have you actually taken temp reading with a thermometer?????????? how about your oil pressure sensor? electric??? if electric do you have temp and pressure sensors or wiring reversed??????


Need more coffee--------------

[Dave Severson]

Yeah, what Jerry said!!!

One of my Dad's favorite old sayings applies here, too, "If you don't have the time and money to do it right, when are you going to have the time and money to do it over???

[jerry clayton]

One more item---------you said that you installed the cam bearings and that you clocked them---------just exactly how did you go about installing them----tools and equipment?????????????

[aahx2011]

I used a cam bearing install tool, measured the cam bearing journals and matched the measurements up to the correct bearing. I installed them with oil hole in the four o'clock position from the top of the engine. I did get the oil pressure and the overheating problems solved. The oil pressure was a mistake on my part and left the oil galley plugs out of the front of the motor behind the cam gear, the overheating was due to a defective clutch fan I now have 50 psi of oil pressure at an idle from a fresh start and warmed up. The engine also does not climb above 180 with out a thermostat installed which it is getting as soon as I get to the store today. I would like to say thank you for all the help, I know I made a stupid mistake one that I can say I will not be making again in the future. And I am still going to build another engine from my old block as soon as I get it back from the machine shop with all the final specs.

[rspears]

HOORAY!!!
Thanks for coming back with the story of what you found. I think I said before I always drill a nominal 1/8" hole in the thermostat poppet to let air bleed out. The trickle through that hole when it's closed, trying to warm up is all but insignificant, but the benefits of hearing the air bubble out are of great value.

[aahx2011]

Thinking of building a 383 stroker, however a friend of mine keeps mentioning a destrocker type of engine. Not sure what he means my destroker, also not sure of if a 383 strocker is worth all of the work or not, I hear a lot of people who love them and some who do not. I would be putting it in a 4X4 truck with a manual transmission, anybody got any suggestions or comments on the thought of a strocker or what a destrocker is?

[Dave Severson]

As for building torque into a SBC, an old "rule" comes to mind, There's no replacement for displacement!!! A 383 (or larger) stroker kit with the correctly matched hydraulic roller cam would build a ton of torque!

[aahx2011]

Dave, any suggestions on a good cam and should I go with a cam kit or buy the pieces individually. This one will be almost all torque for a pulling truck and trailer truck will probably never see a paved road in it's life.

[34_40]

A "de-stroker" = means less stroke than stock, a "Stroker" generally means you're adding more stroke than stock.

The ancient mantra that Dave S. quotes still holds true. There will never be a replacement for displacement in hot rods.

Find a cam company you're interesting in working with and discuss your requirements and needs... although there are a few guys here that can help guide you with some good decisions that'll help get you started.

[aahx2011]

34_40 thanks for the info and clearing up the confusion for me. I will definatley be increasing the strock and going with a 383 now that I get what is going on a little better.

[glennsexton]

Here’s a re-post of a 383 combination that I know works very well together with “off-the-shelf” parts installed in a properly prepared block. That said, I used a flat tappet cam in this build and if I were to do it today, I’d opt for a roller. I like the looks of the Lunati 270-278 Voodoo (but have not personally used it – others on the site may have firsthand experience with this cam) and they sell a kit with the cam and lifters (Part Number 60111SK).That means your block has to be set up for a roller cam and lifters, but there are a lot of them out there. Rollers are a bit more money up front as well – but with the changes in oil, it’s worth considering as the break in with flat tappet cams is critical and a new cam can be ruined in short order if not done properly.

First and foremost – find a good machine shop where you can talk to the machinist who will be doing the work. The prep on your block is critical. The 383 can be a screamer if built correctly, but heaven help you if clearances are not correct as the whole thing will come apart and you’ll have one very expensive door stop! Make sure that the machinist has built many 383 motors. I know everyone has to learn somewhere – but you don’t want it to be your engine.

Have the block cleaned and tested – no need to build a block that has cracks or cannot be squared. Make sure that the machine shop understands that you’ll be building a screamer so you want to have the crank journals align bored and the decks cut to 9.003”. Have the machine shop install new cam bearings and new brass freeze plugs. Also have the machinist go over the location of all the galley plugs with you so you know where they are and that they have been properly installed. When you get the block back from the machine shop make sure you really scrub that baby down with hot soapy water. I like Dawn dish washing liquid and water straight from the bottom of the water heater. Put the block on the engine stand and dry with compressed air really well.

Paint the inside of the engine with Glyptal. Its $50 a quart from Eastwood – buy the brush on and a quart will do the job real nice. Also paint the exterior at this time too with some good high temperature block paint. I like VHT brand in the rattle can and have had good success with it over the years and their Chevy orange is spot on for color. Let everything dry real well. If you don’t have heat in your garage, you may want to opt for a small portable unit (with a sealed heating element) to assist in the drying process. I mention sealed heating unit as you never want to promote a flash-fire with a glowing element near any combustible vapors.

Rotating assemblies are really your choice. Eagle makes a kit that includes crank, flexplate, damper, rods, bearings, pistons and rings for $850. (Some here hate the Eagle components and others have had issues with Scat. I’ve used both and not had problems and believe either to be fine if you take your time and measure everything as you go.) Part number from Summit is ESP-B13005E030. It’s probably fine for your application – uses a -7cc flat top and with the deck height recommended above (9.003”) should keep you in the 10-10.5:1 compression ratio with a .041 head gasket. Have your machinist press the pistons and rods together – it’s a bit tricky if you’ve not done it a lot and you need a press.

Use lots of good assembly lube (I like Red Line). Keep your hands really clean and wipe thing as you go (remember I told you to paint the engine? Lot’s easier to keep nice and clean with fresh paint inside and out!)

I like the Milodon lubrication components and have used several variations of their pump. I used to use the 18750 high volume/high pressure pump but have reverted back to the 18756 high volume/standard pressure and it works just fine with a Milodon 30901, 7 quart pan that fits stroker motors. The pan may need a bit of adjustment with Eagle rods. Use Milodon 18756 oil pump with a 18314 pickup. Use Milodon 23050 oil pump drive shaft and 41000 one piece gasket. Milodon 81300 is an oil pan stud bolt kit – worth the $20 for ease of assembly.

Top the engine off with the components listed below:
AFR 1040 195 Street Eliminator heads
Double roller timing set - Summit is fine
Edelbrock 2102 cam and lifter kit
Edelbrock 7104 Performer RPM manifold
Summit 210216 Summit Q-Jet, 750 CFM
Fel-Pro 1205 intake manifold gasket
Fel-Pro 1003 head gasket
HEI Ignition - stock Chevy is a good unit - pair with a MSD ignition

Remember that this is supposed to be fun so stop when you’re tired or if things start to become irksome. Write everything down as you go and you’ll end up with an engine diary for your build. Can’t tell you how many times I’ve references previous builds and you’ll be able to share your experiences with others who ask.

Let us know when you start the build so we can share in your project!
Glenn

[Dave Severson]

Dave, any suggestions on a good cam and should I go with a cam kit or buy the pieces individually. This one will be almost all torque for a pulling truck and trailer truck will probably never see a paved road in it's life.

I use "Cam Quest", a free download from Comp Cams, and follow that up with a phone call to one of their techs.....

[pat mccarthy]

Glenn hate is a strong word i am a dealer for both scat / eagle and many others eagle cranks very hard to beat scats .this is where it.s comes to over all looks of the crank then getting down to putting a mic on it and checking the stroke the PEP s i think have a edge on them both but i only buy and use about 10 new cranks a year . milodon still make a never nice oil pan.i still use them i would watch there oil pumps as the casting are not as clean as they should be oil ports packed with red sand /clay from casting ?.but the pump should come apart for a prep job . last can of VHT sucked. i could eat a orange and piss a thicker chevy engine color . but use what you like i just know what works for me

[rspears]

i am a dealer for both scat / eagle and many others eagle cranks very hard to beat scats .

Can you help me understand what you've said in the above, taken directly from your post?