Thread: What do you guys think about this combo for my 355

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OKay I have a set of 062 vortec heads that are 64cc. Guides cut etc etc. I have a block bored .030 over and I am in need of all the other parts.

I am thinking about buying some of the D dish Keith Blaack pistons that are something like 22cc. I am thinking its gonna be something around 8.7:1 compression.

What kind of power numbers do you think I could realistically achieve? Whats a good cam? Any other suggestions?
This engine is for my jeep CJ7 I want something with good power but also want decent road manners etc. its gonna kinda be a daily driver.
Thanks

Brian

Anyone with any suggesstions? I would like around 325-350 hp. But I want something I can also use as a daily driver. techinspector you out there?

Why so low on the C/R ? With those heads you can run right up to 9.5 actual compression. That means without decking the block etc.. purchase 10 to 1 and standard 0.040 compressed gasket with the down the hole deck to get an actual 9.5+.
It will run fine on pump gas and full 40 degrees total timing. It is free torque , use it

Originally Posted by LURCHBIOTCH

I want something with good power but also want decent road manners etc. its gonna kinda be a daily driver.

OK, I'm going to take you at your word here and put together a nice little daily driver 355....

Deck the block to 9.013" block deck height. Using a piston with a compression height of 1.561", this will set the piston deck height at 0.012" and square the block up. We'll use a GM 10105117 head gasket that compresses to 0.028" for a squish of 0.040". Squaring up the decks end to end (parallel with the main bearing bore) will also go a long ways toward insuring that the intake manifold/cylinder head interface will be square to prevent vacuum leaks.

Keith Black hypereutectic pistons #KB142 18cc D-cup. You miscalculated the static compression ratio with an 18cc piston. With 64cc heads, the static compression ratio is 9.1:1 and that, in my opinion, is close to the perfect scr to run with iron heads and a modest cam. (Remember, daily driver).
http://kb-silvolite.com/performance....tails&P_id=154

CompCams #12-208-2 flat tappet hydraulic cam, using stock ratio 1.5 rockers. 1.6 rockers will only add unnecessary stress to the cam/lifters and will show only single digit hp and torque gains. (Remember, daily driver). Install the cam advanced 2 degrees (intake closes 33.5 degrees ABDC @ 0.050" tappet lift).
http://www.compcams.com/Cam_Specs/Ca...?csid=104&sb=0
Use Comp #981 springs that incorporate a spiral wound damper spring to control spring harmonics, #742 7-degree retainers and #648 7-degree locks. Install at 1.700". See post #6 on this thread for suggestions concerning the installation of flat tappet cams....
http://www.hotrodders.com/forum/cam-...ht=Racer+Brown
It caused quite a lot of controversy, but somebody had to do it....extreme pressure lubricants have been removed from motor oils for the most part and I see more and more roached cams as a result.

Alternately, use GM Z-28 springs, retainers and locks. Scoggin-Dickey has these in a spring/retainer/lock kit under part number SD1004. Install at 1.735". They are a little less money than the Comp pieces and will do the same job.
www.sdparts.com

Edelbrock #7116 RPM Vortec intake manifold with 600/650 square bore carburetor of your choice. Polished is #71161, Endurashine is #71164. I'd like to use a high-rise, dual-plane Vortec intake mounting a Quadrajet on this build, but nobody makes the manifold to do it. Alternately, you could use a Professional Products Crosswind Vortec high-rise intake manifold, #52028 satin or #52027 polished in place of the Edelbrock manifold. It's a little less money and will do the same job. There's a used 7116 on ebay right now, item #120457563835.

Fel-Pro has a new intake gasket set for the Vortec heads that is supposed to be the hot ticket....# MS98000T. For best results, use Scoggin-Dickey intake manifold bolt kit #SD12550027.

Use full-length, long-tube headers, 1 5/8" primary tubes with 3/8" thick flanges to reduce warping. Install an "X" pipe right after the collectors, before the mufflers. Run 2 1/4" pipes (no need for any bigger on a 355) to the rear of the Jeep. Terminating the pipes under the Jeep will make you nuts after a while from the drone noise. Use any mufflers you want, but I like glasspacks. I'd use 3" core X 36" long like these....
http://cgi.ebay.com/ebaymotors/HEART...Q5fAccessories

Use this 8" rebuilt damper on the crank snout. Wrap it with a degreed timing tape after you have verified that the notch on the inertia ring is at absolutely TDC at your timing tab with the #1 piston at TDC.
http://www.damperdoctor.com/Merchant...egory_Code=CHE
Here's a tape for an 8" damper....
http://www.jegs.com/i/Mr-Gasket/720/1591/10002/-1
Or use a ProForm damper cover like this....never mind that it says Big Block, it'll fit the 8" damper on your Small Block....
http://paw-engineparts.com/shoppingc...568&catid=1249

On trial assembly, follow the instructions here to make sure the heads and manifold are parallel in both planes. I wrote this for the Crankshaft Coalition wiki....
http://www.crankshaftcoalition.com/w...ak%2C_internal

I'd use a standard GM HEI distributor, although if I started with a used one, I'd tear it down and rebuild it, tightening up the end play.
http://rmcavoy.freeshell.org/HEI.html
Vortec heads have a very efficient chamber, so the motor will not need as much total (initial + centrifugal) ignition lead as other heads. Use an advance curve kit to put 20 degrees centrifugal lead into the distributor and begin your initial advance at 12 degrees BTDC for a total (initial + centrifugal) of 32 degrees BTDC. Dial in a little more at the crank one degree at a time and see if the motor likes it. You shouldn't need more than 34 degrees total with the Vortec chambers. Use a vacuum advance can and connect it to manifold vacuum.

Pin the rocker studs with a Mr Gasket kit....#806G.

If you have any money left over, Scorpion roller rail rockers would be a nice addition. The needle bearing trunnion will lower oil temperature and free up a little hp from reduced friction....#1035
http://scorpionperformance.com/newsi...1_no_%20MD.jpg

On your trial assembly, make sure the pushrods have clearance where they come up through the head, through the full travel of valve lift.

RPM HP TQ
2000 144 378
2500 181 381
3000 231 405
3500 283 425
4000 329 433
4500 361 421
5000 373 391
5500 335 320

Static compression ratio 9.1:1
Dynamic compression ratio 8.08:1
Volumetric efficiency 91.1% @4500
BMEP 183.5 @4000

There now, a nice little high-torque daily driver 355 that should run happily ever after on cat-piss pump gas.

Yeah, like Techinspector1 says. I wish all builds were that easy.
Keith

yeah...what he said, lol

Cat piss meaning 87?

Very nice tech very through. I have a couple questions:
The block has already been decked to what degree I dont know. Do I need to take it back and have them measure and possibly cut it some more?

Also about the heads. I bought my heads already rebuilt with new crane springs. I dont know which ones they used though. Do i need to dissasemble the heads and replace them?

You said I should use a quadrajet? So I should get a square to spread bore adapter?

Finally since my heads have guide plates can i use standard stamped rocker arms. Or am I that much better off with the scorpion ones?

"Cat piss meaning 87?"

Yes.

"Very nice tech very through. I have a couple questions:
The block has already been decked to what degree I dont know. Do I need to take it back and have them measure and possibly cut it some more?"

Probably not. Install the crank on oiled bearings. Snug the main cap bolts. Install a piston/rod assembly (less rings) into #1 cylinder on oiled rod bearing inserts. Snug the rod caps down. Make sure you turn the rod so that the chamfer is next to the cheek at the counterweight. Doesn't matter whether the piston is facing front or back for this measurement. Bring the crank around so that the piston is at TDC and measure the piston deck height. I don't know if you have precision tools, but you can do this with tools as simple as a steel rule and a set of feeler gauges. Stand the rule up on edge and span across the bore about 1/4" from the edge of the bore at either the 3 O'Clock or 9 O'Clock position as you are standing at the side of the block. Insert different feeler gauge blades between the bottom edge of the rule and the piston crown until you find a blade that will just slide in there with a little resistance. That will tell you the piston deck height. Be careful that you don't push the piston down in the bore after you have it at TDC. Move the crank back and forth a little each way and check with blades until you find the least blade measurement that will fit. Having a buddy hold a long bar and socket on the slightly tightened harmonic damper retaining bolt will help keep the crank where you want it to do this operation. Once you have #1 done, write it down and remove the piston/rod assembly. Now, using the same rod/piston assembly, install them into #7, #2 and #8 and repeat the measuring operation. Now you have the piston deck height on each of the four corners of the block and will know whether or not the block is square. Report the measurements here and we'll go for there.

"Also about the heads. I bought my heads already rebuilt with new crane springs. I dont know which ones they used though. Do i need to dissasemble the heads and replace them?"

Probably not. Post the particulars on the springs here. Installed height. Seat pressure. Open pressure. Spring rate.

"You said I should use a quadrajet? So I should get a square to spread bore adapter?"

No, those never work like they should. The transition is too abrupt. Use the small square bore carb.

"Finally since my heads have guide plates can i use standard stamped rocker arms. Or am I that much better off with the scorpion ones?"

Yes, use standard stamped rockers or non-rail aftermarket roller rockers. I didn't know you had the guide plates. Disregard what I said about pinning the studs. You have screw-in studs.

Okay sounds good tech. I will get back to you when I have these measurements. I am guessing the best way to determine the spring pressure, seat pressure, etc. Is to just take them to a machine shop where they have the tools for that kinda stuff?
Also....
.....what kind of square bore carb do you reccomend?
.....I have read a few other posts by you and you always rec the Keith Black D dish pistons. Why are you so fond of these? Just my own curiosities.
.....Is it considerably better to use roller rockers as opposed to the stamped variety?

Originally Posted by LURCHBIOTCH

Okay sounds good tech. I will get back to you when I have these measurements. I am guessing the best way to determine the spring pressure, seat pressure, etc. Is to just take them to a machine shop where they have the tools for that kinda stuff?
Also....
.....what kind of square bore carb do you reccomend?
.....I have read a few other posts by you and you always rec the Keith Black D dish pistons. Why are you so fond of these? Just my own curiosities.
.....Is it considerably better to use roller rockers as opposed to the stamped variety?

If you don't have the part number of the springs so that you can find the specs on them, remove one only and take it to a reliable engine builder in your area to be checked out on his spring tester. Comp specs the springs for this cam to measure 105 lbs at the installed height of 1.700" and 273 lbs at 1.250".

Square bore equals Edelbrock, Carter AFB, Holley, Barry Grant, etc.

I like the KB's because they are a premium quality piston and utilize a large flat area on the crown to mate up against the bottom of the cylinder head to produce an excellent squish of the air/fuel mixture toward the spark plug as the piston approaches top dead center. Check the large flat area on these pistons as a result of the offset D dishes as compared to other pistons that utilize a concentric dish. No comparison.

Roller tips on these aftermarket rockers are too small to generate a mechanical couple on the valve tip and have been shown to skid across the tip under high speed photography. Where these things shine is the needle bearing trunnion. That's where you are going to reduce friction to free up a little free horsepower and lower engine oil temperatures. In my opinion, Harland Sharp makes the best ones. Some of the first ones (Crane, etc.) were designed with the wrong geometry, but I'm told that HS has corrected this error. A line drawn through the pushrod axis and a line drawn through the rocker pushrod tip/trunnion should ideally be at 90 degrees to each other with the valve at half lift. Additionally, a line drawn through the rocker trunnion to the bottom of the rocker roller where it contacts the valve stem tip and the valve stem axis should be at 90 degrees to each other with the valve at half lift.

It has been said by some respected engine builders that you can pick up 20 hp in addition to lower oil temps with roller rockers (roller bearing trunnions).