[Elkyblack]

Whats good guys? Need your opinions and advice
Ok here it goes, just bought a 5.7 Vortec motor today. Im thinking of removing a sbc 350 with double hump 291 heads, comp 280h cam, Edel Airgap,holley 750, stock bore with stock dish pistons. out of my el camino. and building up this Vortec, By the way I have a th350 with b&m 2400 stall with 373 gears. Would this be a good idea? I would like to have a nice torquey motor for mostly street that sounds nice and performs great. Would it benefit me at all to build up the vortec motor? If so which mods. The motor was pulled from a wrecked 1998 Chevy 1500. Any and all advice would be appreciated. Thanks

[techinspector1]

Originally Posted by Elkyblack

Whats good guys? Need your opinions and advice
Ok here it goes, just bought a 5.7 Vortec motor today. Im thinking of removing a sbc 350 with double hump 291 heads, comp 280h cam, Edel Airgap,holley 750, stock bore with stock dish pistons. out of my el camino. and building up this Vortec, By the way I have a th350 with b&m 2400 stall with 373 gears. Would this be a good idea? I would like to have a nice torquey motor for mostly street that sounds nice and performs great. Would it benefit me at all to build up the vortec motor? If so which mods. The motor was pulled from a wrecked 1998 Chevy 1500. Any and all advice would be appreciated. Thanks

Assuming you planned on bolting on an intake manifold and carb....
Bore the block +0.030" and use these pistons. Cut the block decks for zero deck and use a 0.041" compressed gasket for 9.6:1 static compression ratio and 0.041" squish.
http://www.kb-silvolite.com/kb_car/p...tails&P_id=155
http://www.summitracing.com/parts/FPP-1003/

The problem with using more lift with the stock L31 springs is that the bottom of the retainer crashes into the guide seal with lifts over (depending on whom you talk to) 0.430" to 0.450". There is more play than that, but you must leave some of it for a safety margin. Crane Cams makes a drop-in spring and retainer that requires no machine work and leaves the stock seal in place for a 0.640" max net lift capability. You won't be able to use that much lift though, because the tappets can drop down below the dogbones at lifts exeeding about 0.535" (not absolutely sure about this figure, but I think Cobalt has it and will probably correct me with the right figure). Also, sometimes the seal is not pushed fully onto the guide at the factory, so use a 1/2" socket to tap the seal home before assembling the springs onto the heads.
http://cranecams.com/?show=browsePar...Number=10309-1
http://www.summitracing.com/parts/CRN-10309-1/
Spring description:
O.D. 1.255"
I.D. 0.870"
Seat pressure 124# @1.750" installed height
Open pressure 374# @1.150"
Coil bind 1.100"
Rate 409#/inch
CompCams 08-432-8 hydraulic roller camshaft. Use the stock L31 roller lifters, dogbones and spider.
http://www.summitracing.com/parts/CCA-08-432-8/
http://www.compcams.com/Company/CC/c...?csid=189&sb=0
Edelbrock 7116 RPM Vortec intake manifold mounting 750 carb of your choice, vacuum secondaries.
http://www.summitracing.com/parts/EDL-7116/
1 5/8" long tube headers
RPM HP TQ
2000 133 350
2500 169 356
3000 218 381
3500 278 417
4000 334 439
4500 383 450
5000 417 438
5500 441 421
6000 445 390
6500 417 337
Peak volumetric efficiency 99.0% @5000
Peak BMEP 189.5 @4500
Use manual trans or 2500 stall converter with auto trans. Use 3.73 or shorter gear.

[turbolover]

I agree with everything Techinspector said, but I'd go one step smaller on the cam. Stock Vortec heads don't see much gain after about 220-225 intake duration (.050" numbers)- especially on street engines.

[Elkyblack]

Ok, so you think building the vortec motor would benefit more than the motor I already have?

[turbolover]

Originally Posted by Elkyblack

Ok, so you think building the vortec motor would benefit more than the motor I already have?

Yes. Especially if those 291 heads are stock. HOWEVER you need to weigh the cost VS reward. You can expect to gain about 50hp and 50 tq but to build the engine will cost you about 3 grand and you could sell the one in your camino for about $500, if you part the engine out you could maybe get about $700.

[zildjian4life218]

Originally Posted by Elkyblack

Ok, so you think building the vortec motor would benefit more than the motor I already have?

Definitely. It has a roller cam from the factory and the heads flow better than the old camel humps.

[Elkyblack]

Ok, just kinda inherited a eagle cast 383 crank for the late 5.7 motors. Can anyone give me a good combo using this in my vortec motor?

[zildjian4life218]

Originally Posted by Elkyblack

Ok, just kinda inherited a eagle cast 383 crank for the late 5.7 motors. Can anyone give me a good combo using this in my vortec motor?

First send the crank off to be checked over by a machinist who can make sure its all good. I have never used an eagle crank but never really heard great things about them.
change the pistons to ones with a different compression height like: http://www.summitracing.com/parts/UE...-030/?rtype=10

Your compression will remain around 9.6:1

[V8 Super Beetle]

Originally Posted by zildjian4life218

First send the crank off to be checked over by a machinist who can make sure its all good. I have never used an eagle crank but never really heard great things about them.
change the pistons to ones with a different compression height like: http://www.summitracing.com/parts/UE...-030/?rtype=10

Your compression will remain around 9.6:1

I had mine, 3.75 internal balance Eagle crank, checked out by a machine shop and the journals were a hair on the big side. That was ok because my rods were a hair on the big side after resizing. All bearing clearance were between .0018 - .002.

The problem I ran into was I didn't know you need narrow bearings. I can't recall the part number, but I believe they were H series, or N series (?)( Clevite bearings. Eagle cranks have a little extra material, or a bevel / flange where the journals meet the throws. This gives them extra strength over stock cranks.

[turbolover]

Originally Posted by Elkyblack

Ok, just kinda inherited a eagle cast 383 crank for the late 5.7 motors. Can anyone give me a good combo using this in my vortec motor?

Just change the pistons as noted, the rest will work just fine.

[V8 Super Beetle]

Originally Posted by Elkyblack

Ok, just kinda inherited a eagle cast 383 crank for the late 5.7 motors. Can anyone give me a good combo using this in my vortec motor?

The same setup Tech put together, but with the pistons zildjian recommend for a 383, should work nicely. You'll more than likely at least pickup another 20hp and 30 ft / lbs.

Although, you'll have to grind the rods and possibly the oil pan rails so the 3.75 crank will live comfortably. I would recommend getting a small base camshaft to avoid having to grind on your rods or get some 5.7 eagle rods with have more shoulder clearance. You'll still more than likely have to kiss the eagle rod shoulders to get the needed .05 clearance between the cam and rod shoulder.

With the KB135-030 pistons and the block zero decked, you'll arrive at a 9.008 stack. To keep the squish within the .035 - .045 range you would need to go with a gasket no larger than .037".

[zildjian4life218]

Originally Posted by V8 Super Beetle

The problem I ran into was I didn't know you need narrow bearings. I can't recall the part number, but I believe they were H series, or N series (?)( Clevite bearings.

yup H series...http://www.competitionproducts.com/C.../products/738/

[Elkyblack]

Thanks for all the input guys. So basically the combo Tech put together with the pistons Z recommended with the 383 crank should be a solid combo. What would the sound quality be with that cam Tech recommended, and what kinda power would this motor yield with this combo.

[V8 Super Beetle]

Originally Posted by Elkyblack

Thanks for all the input guys. So basically the combo Tech put together with the pistons Z recommended with the 383 crank should be a solid combo. What would the sound quality be with that cam Tech recommended, and what kinda power would this motor yield with this combo.

It'll sound like this cam. Same specs. 110 LSA, 230/236.

http://www.youtube.com/watch?v=V10Ks0_aXk8


Look in the previous post #2 for power. I would guess around 450 hp and 475 tq with the 383 setup.

[turbolover]

a smaller cam would produce better torque and not give up much at all in terms of hp. The cam recommended will sound nicer but dropping about 5-10 degrees will save you gas and gain you performance for the street.