Hello all! I've posted about this build before, so some might remember my build info. I started this build earlier this summer, slowly getting pieces and parts together making sure I have the very best recipe for power. I'm sorry this is gonna be long, and if you could see my face...depressing! Anyway..the build. It is in a 1970 Challenger 99% street car. I started with a 440 block + .040 = 4.360. I bought the 440Source stroker kit for 512ci. -27 dish, -.010 below deck, ARP2000 bolts, V series main bearing, H series rods. Total seal file-to-fit rings. Block was line honed, new cam bearings, etc. Typical machine shop work done on block. I put engine together (no one to blame but me now). I have build engines since the 70's so I have done a few. I've put engines together with an impact gun that runs better than this 512! Anyway to the build, Measured everything. Mains .0025, rods: .002, rod side clearance: .020. No clearance issues with the crank or rods to the block. Ring gap may be a tad large. top: .024, second: .026. Meling HV oil pump, 6qt pan, windage tray. Cam is a Comp purchased from Indy Cyl. Gross lift: .511 duration: 246 @ .050 108.0 intake CL installed at 107. I did degree the cam and double checked myself, although still could be wrong, this was my first time to actually degree. I always just set up dot-to-dot. I followed instructions to the "T". INDY-EZ cyl heads, INDY black 1.5 rockers, INDY valve covers. Stock 6PAK set-up. Manton 9.500" pushrods. MSD Pro billet dist, MSD coil, MSD 6 box. FireCore wires, Champion C57YC plugs. Broke in at 2000RPMs for about 10mins, started initial tune......
I have initial timing at 16 all in by 3K total of 38 deg. I have adjusted timing numerous times, adjusted carbs numerous times. Engine is very hard to start, extended crank time, kicks back, back-fires thru carb. Finally get to start, runs "rough" and I hear a slight "rattling" noise. I have heard other engines with roller rockers make some noise too, so not too concerned abt that for now. I can rev to only about 5500rpm until it seems like that's all it's got. REV limiter at 7000RPM. So, I take it out for a test drive..NO power at all. I doubt if it would burn rubber! Seems like a slight miss out at light cruise.
I have taken out plugs. Might be a bit rich, Looked in chamber with a Snap-On bore scope, adjusted rockers ICE-EOI method 3 times! I'm LOST! If there was a Mopar only shop around, I'd pay what-ever to have this re-done so it's right! I'm embarrassed to give up, I thought I was better than this. Maybe someone might have a suggestion for me. Thanks guy's for even taking the time to read this!
Take care! Jeff

I would check compression in all the cylinders first and check the vacuum the engine pulls at idle.

Im no expert but that is where I would start. Good Luck on straightening this out.

my first thought , cam not in correctly,
dont want to sound mean or anything, it is very easy to get it wrong!

have you done a compression test or leak down test to see what you have? firing order correct and in right direction? check spark? how much advance is the dist. giving you? lots of questions/more info needed. when you degreed it, how close was it to dot-to-dot?

Any way to describe exactly how you degreed the cam? Do you have a cam card you can scan and post?

I agree with the checking of the plug wires also, Get 2 of them switched at the cap and I have heard the engine sound like you describe.

Dont ask me why I know that plug wire deal. It was easier for me to figure that out as after I only changed the wires it sounded terrible.

Double check all the easy stuff wires timing etc then do the leak down/ compression check / vacuum

I had the same issues with a 440 I slammed together. Turned out I installed the cam 180 out!! Check into it. I did exactly what you are talking about. Also this is simple but I will but it out there are you spark plug wire in the proper location!!!! Probably, but worth a look!!

Check TDC against the marks on the balancer. You could have a faulty or slipped balancer, and thus your timing could be way out of whack.

I'm doubting a stroker would even run at all with the cam 180 out, but I guess anything's possible. I would first verify your timing by indexing your dizz to #1 and probing the #1 spark plug hole to make sure you're at TDC and both valves are closed. Verify your firing order again, just like you were doing everything from scratch.....assume nothing is correct.

Make sure you're cam doesn't have something unusual specified like a 4-7 swap and also it's key to know that timing for most strokers won't fall out of a tree if the initial timing is too low, most of my motors want around 22 initial and then a realitively slow centrifugal limited to 12-14 max. Too low a timing and the motor will run like warmed over crap no matter how good the parts are.

Make sure you didn't suck a big slug of rust or dirt into your fuel line....if in doubt blow it out and verify free flow to the bowls. check your needle and seat that there's no debris there too. Pull the valve covers and turn it over, If I know it's all good I usually do the screwdriver to starter relay 'jumper' trick just so I can verify the valves and firing order, but it's better to slip a big wrench on the crank pullay and do it slowly by hand. Go slow and make 100% all valves are seating (if cam timing was bad off something could have hit) by rocking the arms at TDC...again assume nothing and that anything could be the culprit. Lash ands preload can still be a bear if you're out of practice....even if you know you know what you're doing.

try those things and then come back...we'll go to the next level from there.

x 2 ...on checking cam-timing and dampner marks.

Look for the easy things first as some of the above have mentioned. Also, is your distributor drive gear in the correct position?

speaking of that, i've had a drive gear spin on the shaft before and throw off the timing.

I would start back to cam timing,dot to dot and set total to 32*
That combo on pump gas with 38*is not ideal IMHO 34 should be max total advance with a base around 22 with around 10 advance and that should get you running good.
Gus

Hate to admit this but when i was putting my 432 together I caught myself trying to degree cam in on exh lobe doooohhhh tip off is when you need to retard to advance cam timing. I hope im not the only one to have done that

One quick wat to check cam timing is the old fashion way of looking at the rockers at TDC in the overlap stroke when the exhaust is closing and the intake is opening at TDC. It looks like you have a dial indicator and magnetic base so check the valve opening at TDC in the overlap to see if the valves are opening and closing close to the same amount at TDC, IE, exhaust is .045 from closing and the intake is .045 opened hieght If there close (+ or- .015) you are close on the cam timing, if it is not then get out the rest of the tools and recheck the cam timing BTW, I have degreed more than one cam on the exhaust lobes and had to redo them when I realized that I had goof up No one is perfect I have had cams be off on the dots by one tooth, that is about 12 degrees on a stock double roller timing set BB, they don't run worth a hoot when the cam is that far off They do sound ferousous(mean) in nuetral but don't pull worth a hoot in gear Good luck, you can fix it, it is just a matter of figuring out what is wrong 512 make a hoop of power

Hi Everyone. Great suggestions. I'm going to do a compression test tomorrow. To answer some questions. The damper is new SFI and I did check it to TDC, right on zero. I have cranked the engine and watched valve train, all open and close as the should. I admit, may have valves too tight / too loose. I did 3/4 turn past zero lash. The response about using intake or exh lobe to degree cam has me thinking tho! I have the timing set with multiple key ways on the crank gear. I advanced that gear to the 2 deg advance key to the cam dot. The cam was at 109 dot-to-dot, so I advanced it 2 deg to be at 107. I have double/triple checked the firing order. Now, the dist drive gear. I dropped the drive gear in and then lined up plug wire #1 to start engine. I wouldn't think the gear placement would matter as long as #1 line up at TDC. I have tried advancing the dist untill the eng cranked hard, no difference. From the beginning, I have had the "rattling" type noise. Sounds like piston "slap" doesn't get any better after engine is warmed. IS this normal for roller rockers / alumn heads? Thanks again everyone! Jeff

Sounds like a good solid set of parts. Definitely geared toward your application of 99% street.

Which version of the EZ heads did you buy?
The stock six pack intake and carbs will be a limitation, but pretty cool looking on a street car. Not a lot of duration for 500+ CID (4.360 x 4.250 = 507.6 CID), but OK for 99% street.

Being -27 dish, -.010 below deck, it will be mild on compression ratio. The rpm issue could be many things, including valve springs, what was the actual measured pressure on the seat and open? Don't expect much power higher in the rpm band with the combo you put together. Head restricted, intake, converter stall speed, headers? etc.

I second the suggestions to start rechecking all the basics.

I'm thinking you said you lined up the dots and set the dampener to TDC....but when the dots are phased on the cam/crank gear you're not on the compression stroke, so you're essentially 360 out with the distributor. You want to be tdc AND make certain both your #1 valves are closed. when you're on the compression stroke your cam and crank dots are both at 12:00, not 6:00 and 12:00 like when you're lining them up. Remember there's 2 TDC's

Hopefully that's all it is. Usually the KISS Pyrotechnic show out of your carb is a good indication