Engine Build Ideas

[ol'blu72]

So I think my engine build is actually going to happen. Well I should say rebuild. I saved almost enough money and can con the wife out of the rest lol. I have a small water leak comming from the back of the drivers head. I also have knocking noise comming from the belhousing area. Im told this is probably a cracked flexplate.
Here is the current stats. Its a 72 blazer that is almost totally stock besides the Edelbrock1406 and Edelbrock intake. 32in tires and (i believe) 3.75 gears.

Where I want to go. I want to find a good combination for torque and good street manners. So this is what im thinking

Vortecs
Comp extreme 4X4 cam
performer air gap intake
new Edel 600cfm
CR?

Im looking for any problems with this setup, better ways to go, where I need the CR to be, and any other helpful info. This will be my first build so I am working the learning curve. Here are some of my stupid questions.

Can I go to a roller cam?
I caught some reading about cylinder quench. Where should this be set at?

[blackedoutharley]

Originally Posted by ol'blu72

Vortecs

Good choice if you can score them on a deal.

Originally Posted by ol'blu72

Comp extreme 4X4 cam

Again, good choice depending on which one you pick. Bigger doesn't mean better.

Originally Posted by ol'blu72

performer air gap intake

I would go with a Performer RPM non air gap.

Originally Posted by ol'blu72

new Edel 600cfm

I am not a fan of Edelbrock carbs but you're in the correct cfm rating. No reason to put a huge carb on it either.

Originally Posted by ol'blu72

CR?

No more than 9.5:1 static. That means including head gasket thickness, piston specs, bore diameter etc.

Originally Posted by ol'blu72

Im looking for any problems with this setup, better ways to go, where I need the CR to be, and any other helpful info. This will be my first build so I am working the learning curve. Here are some of my stupid questions.

No question is stupid if you're smart enough to ask it.

Originally Posted by ol'blu72

Can I go to a roller cam?

Yes, in fact a hydraulic roller is a great idea but..... the initial investment for the needed parts is rather spendy.

Originally Posted by ol'blu72

I caught some reading about cylinder quench. Where should this be set at?

Its not a race car... don't worry about this.

Many decisions to be made will be determined by the actual gear ratio (not a guess), what transmission you have and what converter if an auto, any emissions requirements?, what engine you have now", are you going to bore the block and replace everything or just rings & bearings etc?, power brakes that require vac to operate properly?, what exhaust system you're running, what you actually plan to do with the truck as far as real usage and what you want the truck to do, and what your total budget is.

A mild .030" over 350 with a dual plane manifold, 600 cfm carb and small cam can make loads of torque and still be very street friendly without breaking the bank.

Really need more details.

[GASoline71]

That was an awesome post ^^^

Gary

[blackedoutharley]

thanks

[GASoline71]

Gary

[ol'blu72]

I would go with a Performer RPM non air gap.

What would the advantage of the RPM be? I was kind of going for the performer due to its RPM range (Idle-5500ish)

Many decisions to be made will be determined by the actual gear ratio (not a guess)

My SPID says 3.73

what transmission you have and what converter if an auto

stock TH350 with stock converter. What is the stalll speed of the stock converter?

any emissions requirements?

no

what engine you have now

stock 350

are you going to bore the block and replace everything or just rings & bearings etc?

Im planning on just rings and bearings, but that could change depending what is found once I tear into her.

power brakes that require vac to operate properly?

Yes that is part of the reason I want to go mild on the cam. That and she wont be seeing high RPM's as a Sunday cruiser.

what exhaust system you're running

Ramhorns and flowmaster 40's

what you actually plan to do with the truck as far as real usage and what you want the truck to do

She is my sunday driver. I take her out when the weather is nice and cruise. She makes quite a few trips to the beach every year. No track, no racing. Thats not to say I wont "get on her" cause I plan on it, but that is not the intent.

and what your total budget is.

Im planning on about 2k with some flexability.

[blackedoutharley]

Originally Posted by ol'blu72

What would the advantage of the RPM be? I was kind of going for the performer due to its RPM range (Idle-5500ish)

For me the main thing is I don't like running an adapter on a spread bore manifold to run a square bore carb. I like simplicity and a square bore Holley on a square bore intake is as simple as it gets. I also feel that the RPM does a better job across the mid range but my take on it is not scientific. If you want to stick with the idle -5500 rpm range I would steer you to the Performer EPS.
http://www.summitracing.com/parts/EDL-2701/

Originally Posted by ol'blu72

My SPID says 3.73

I probably know what SPID means but right now I am drawing a blank.

Originally Posted by ol'blu72

stock TH350 with stock converter. What is the stalll speed of the stock converter?

I don't know the factory stall but I would imagine it isn't lower than 1500 rpm (where the Performer RPM manifold starts making power btw).

Originally Posted by ol'blu72

stock 350

Stock as in 4.00" bore and is it an early engine? How many miles? What compression ratio (or piston type)? etc..

Originally Posted by ol'blu72

Im planning on just rings and bearings, but that could change depending what is found once I tear into her.

Lets assume that the engine is cherry with no ridge on the top of the cylinders, folded ring lands, scored bearings etc... meaning that honing the cylinders and a good cleaning is all the block and rotating assembly needs. continued below.

Originally Posted by ol'blu72

Ramhorns and flowmaster 40's

Nothing wrong with ramhorns and they are virtually foolproof.

Originally Posted by ol'blu72

She is my sunday driver. I take her out when the weather is nice and cruise. She makes quite a few trips to the beach every year. No track, no racing. Thats not to say I wont "get on her" cause I plan on it, but that is not the intent.

YES! Somebody with realistic, no b.s. goals on drive-ability!!!!!!!!! FINALLY!

Originally Posted by ol'blu72

Im planning on about 2k with some flexability.

That should be plenty if you're doing the engine removal, assembly and re-install.

Now back to the engine... assuming that the block is good and the cylinders are round and not worn to the point of causing rings to not seat properly etc... here is what I would do if it were mine, given the expectations you have and the planned usage.
After disassembling the engine I would do the following at a reputable machine shop.
1. Have the block thoroughly cleaned and checked overall.
2. Have the crank checked for cracks, measured and if good, polished.
3. Have the rods checked for straightness and resized with new rod bolts installed.
4. Have new cam bearings installed.

I would do the following for the rest...

1. Clean the pistons completely especially the ring lands in preparation for new rings.
2. Run a tap (thread chaser tap specifically) through every threaded hole you can find.
3. Make a decision on cylinder heads (you will probably find that it is cheaper to buy new, ready to run heads than to rebuild yours.
4. Buy a quality gasket set, new oil pump with screen, brass freeze plugs, rings, bearings, etc.
5. Not required but again, this is what I would do; new main, cam, intake and head bolts. You can clean up oil pan bolts etc and reuse them.

Selecting a camshaft is like asking who was the greatest rock guitarist in history... you will get so many different opinions its nearly mind boggling. Based on what you said you wanted, and assuming you're staying with a hydraulic flat tappet cam, I am going to recommend any of the following cams, in no particular order of preference.....

http://www.summitracing.com/parts/CCA-12-207-2/

http://www.summitracing.com/parts/CCA-12-235-2/

http://www.summitracing.com/parts/CCA-12-206-2/

Each one of these are mild and will make great torque on a virtually stock, freshened up, 350.
Don't forget that a new cam also gets new lifters and a timing set.

At this point I doubt that anybody can recommend using old stock rockers given the price of quality roller units these days.

You can get these and they are great units...
http://www.summitracing.com/parts/CCA-1412-16/

But for less than $5 more you can get these.....
http://www.summitracing.com/parts/CCA-17001-16/

Obviously I am partial to Comp Cams products but there are certainly others that are perfectly acceptable (except Erson, They SUCK! LOL).

Just to throw another wrench into the mix.....

You do realize that you can buy a brand new GM crate 350 with a factory 3 year/ 100K warranty that makes 260 HP and 350 Ft Lb of torque for about $1500?

http://www.summitracing.com/parts/NAL-10067353/

Again, for simplicity isn't it easier to just pull one engine and reinstall a new one? That can be done in a weekend easily and there are no guessing games or surprises once you tear your engine apart.

This is a long block... bolt on your intake, water pump and exhaust and go.

[ol'blu72]

I probably know what SPID means but right now I am drawing a blank.

I may have the terminology wrong. I'm talking about the sticker in the glovebox.

I don't know the factory stall but I would imagine it isn't lower than 1500 rpm (where the Performer RPM manifold starts making power btw).

The more I look into it, it seems this is going to be critical for some of the decisions I need to make. If it is 1500 then that would be awesome and it would change what cam and intake I'm going to use and get me more HP.

Stock as in 4.00" bore and is it an early engine? How many miles? What compression ratio (or piston type)? etc..

Like I said it is all stock never rebuilt (as far as I can tell). It has aprox 115,000mi. don't know for sure because the spedo was inop for some time. It is an early engine, 72, so no cheap roller cam I am running most of my numbers for my CR plan off of a stock never bored or decked engine. I will have to see if that's what I got when I break into her.

You do realize that you can buy a brand new GM crate 350 with a factory 3 year/ 100K warranty that makes 260 HP and 350 Ft Lb of torque for about $1500?

No I didnt. WOW!!!!!! That does give me pause. I am partial to rebuilding this eng though because it is the original eng. I would like to keep the truck as original as possible. I know then why am I going for Vortecs? I dont know I think its the lure of more power. I'm thinking I will run the vortecs and tuck away the originals for later.


I appreciate the time you put into that post, it is extremely thorough gave me a lot of ideas. It sounds like I am on the right track I just need to get more numbers and specifics on what I have to see what I need to do. Im just trying to do all my homework so I get this right the first time. Now I just need a place to do the work and Ill get started.

[Psycho71]

I have to wonder, and I know someone will step in here and educate me if I am wrong. But will the Vortecs really help on a vehicle that will rarely see peak RPM's? I am assuming, since it has 32" tires, and you are wanting a Xtreme 4x4 cam, that it's a 4x4, right? if that's the case, it's not like you're going to be twisting the engine to much over 3500rpm, except in rare instances (mudding).

What say ye engine guru's on this way of thinking?

Would a set of Vortecs really be worth the added expense over a set of 882's in a low rpm application?

[ol'blu72]

From what I have been researching the Vortec's do better in the mid range. They flow really well at the lower lifts, in fact you cant even run a cam over 480 lift with them. I've been told people don't like the vortecs for this reason in the high output motors. I am no expert and someone can correct me if needed. But I have been researching this quite a bit lately.

[Psycho71]

I could see that being possible. That's why i didn't post as advice, but more as an inquiry. I've certainly never seen anyone complain after installing a set of Vortecs.

[ol'blu72]

If I'm reading between the lines right their biggest benefit is from a more complete, even burn. I've never read any complaints either, I'm real excited to try them out.

[blackedoutharley]

Originally Posted by ol'blu72

I may have the terminology wrong. I'm talking about the sticker in the glovebox.

Okay, that makes sense but don't rely on a sticker... parts could have been changed over the years. To be certain it is best to pull the cover(s) and count. At the very least you will confirm what you have, get a look at everything for any possible damage and it gets fresh oil.

Originally Posted by ol'blu72

The more I look into it, it seems this is going to be critical for some of the decisions I need to make. If it is 1500 then that would be awesome and it would change what cam and intake I'm going to use and get me more HP.

If it is a stock converter (which is sounds like it is) any of the cams I linked will work great. My questioning it was in case there was a higher stall aftermarket converter in it.

Originally Posted by ol'blu72

Like I said it is all stock never rebuilt (as far as I can tell). It has aprox 115,000mi. don't know for sure because the spedo was inop for some time. It is an early engine, 72, so no cheap roller cam I am running most of my numbers for my CR plan off of a stock never bored or decked engine. I will have to see if that's what I got when I break into her.

I like the optimism but the realistic side of me says that with over 100K, on a 40 year old engine, the chances of getting away with just rings and bearings are slim. In the end, barring the new engine mentioned, you will probably be boring the cylinders and replacing pistons.

Originally Posted by ol'blu72

No I didnt. WOW!!!!!! That does give me pause. I am partial to rebuilding this eng though because it is the original eng. I would like to keep the truck as original as possible. I know then why am I going for Vortecs? I dont know I think its the lure of more power. I'm thinking I will run the vortecs and tuck away the originals for later.

If this was an all numbers matching SS ElCamino, Chevelle, Corvette etc I would say that originality is important. On a Blazer? Not so much. Don't get stuck on originality for the sake of driving pleasure and hassle free motoring.

Originally Posted by ol'blu72

I appreciate the time you put into that post, it is extremely thorough gave me a lot of ideas.

My pleasure.

Originally Posted by Psycho71

I have to wonder, and I know someone will step in here and educate me if I am wrong. But will the Vortecs really help on a vehicle that will rarely see peak RPM's? I am assuming, since it has 32" tires, and you are wanting a Xtreme 4x4 cam, that it's a 4x4, right? if that's the case, it's not like you're going to be twisting the engine to much over 3500rpm, except in rare instances (mudding).

Excellent point! I, for whatever reason, skipped over the 4X4 part. If it is a 4x4 I would probably go with this cam (which I recommended earlier):
http://www.summitracing.com/parts/CCA-12-235-2/
Remember that HP numbers mean nothing in a driver and especially a 4X4 or a truck.... its torque that you're after and its torque that you feel when you step on it.

Originally Posted by Psycho71

Would a set of Vortecs really be worth the added expense over a set of 882's in a low rpm application?

The 882's were an 'okay' head... for the cost of having them completely rebuilt you can buy new iron heads that flow much better. Even the Summit heads are a good deal @ about $600 a pair and I think they are made by Dart.
http://www.summitracing.com/parts/SUM-152123/

And they're on sale right now!

Originally Posted by ol'blu72

From what I have been researching the Vortec's do better in the mid range. They flow really well at the lower lifts, in fact you cant even run a cam over 480 lift with them. I've been told people don't like the vortecs for this reason in the high output motors. I am no expert and someone can correct me if needed. But I have been researching this quite a bit lately.

Again if you can get them on a deal they certainly wont hurt what you're trying to do. There are a few things I don't like about Vortec heads.
1. I think center bolt valve covers look out of place on an older vehicle.
2. You have to run a Vortec specific manifold which is an added expense if you already have one.
3. Most of them require self aligning rockers and again, its an added expense if you already have them.

[mud.man.rj]

Very good realistic engine build here, I agree on the mileage of engine you won't get away with a simple rering/rebearing on it so hardley worth it, the Summit engine would be a wise choice with realiability and warranty which is better than what you will get from an engine shop and finishing it yourself and also the time factor, nice to just replace for the price it should be compareable or even a bit cheaper.

[ol'blu72]

I've been thinking about the summit (dart) heads you suggested a few posts back. Do you think those would make more or less power than the vortecs? How about drive ability and performance at the RPMs I'm looking at (idle to 5500). Does anyone have these heads and have any input, good or bad? I did find a par of vortec straight out of the machine shop for $400 on CL. But I am weighing my options.

[ol'blu72]

Also does anyone know if all my accessories will bolt on with vortec heads?

[mud.man.rj]

Originally Posted by ol'blu72

I've been thinking about the summit (dart) heads you suggested a few posts back. Do you think those would make more or less power than the vortecs? How about drive ability and performance at the RPMs I'm looking at (idle to 5500). Does anyone have these heads and have any input, good or bad? I did find a par of vortec straight out of the machine shop for $400 on CL. But I am weighing my options.

Don't know much on the Dart heads, have heard a lot of good about them, in fact installing a set on a Big block soon, the Vortecs are good but then need an intake to match and don't really look right on an older truck/car with the center bolt covers, just look strange. I installed the Rpm's, totally awesome heads, just a direct replacement but need a head bolt kit with them, they come with guide plates and I like that they can be used with a .500 lift cam with a 350 and up a 283 and up can use a .480 lift I believe so up to a 268 Comp cam which is lots. The price I think was about $589 apiece for aluminum heads, they out flow the Vortecs but cost more so if savind a buck I would use the Vortecs, but for performance the Eddy's Good from idle up either head, if using a Edel intake the Rpm is nice but not airgap as it works exactly the same but takes longer to warm up, ask me how I know in our -15-30 weather we have up here in Northern Canada. Good luck choosing.

[Psycho71]

Another note on the air gap intake, if you're gonna be out doing any serious mudding, then you don't want all that mud laying up under the carb in an air gap. Would be better to have a regular rpm. I wanted the air gap too, but after a little thought I went with the reg. rpm. I've had my burb up to the frame in mud and just hose the mud off the engine when I'm done. It's amazing all the nooks and crannies that mud can find it's way into.

[mud.man.rj]

Your right on the mud thing with the airgap, that is whats on my 71, everything from leaves to mud collects down under there and when they did a comparison on intakes, Airgap to non the HP was the same, makes me want to change it out or Mud less.