318/360 heads,with thumper cam

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7duce swinger said:
Thanks 273,youve been great help,-OldmanRick,yea i dont want to pour to much money down this motor,but ill probly have it for awhile,so i gotta do something now,if i buy an edelbrock intake,can i mill the head surface where the intake touches,or is that not good to do?also i just want a little somethin more,i already have headers,and the thumper i have would be the smallest of the three,the motor was running before i pulled it apart,to cc the heads,theres a few good machine shops in town,one well known is charging 70$ for the milling,and the other shop wants 100$,i think ill do the milling,and thin head gaskets,then maybe zero deck the block,i have headers also.if anyone could let me know whats a safe ammount to mill the heads,i greatly appreciate it thanks.
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If your willing to zero deck and get a performance intake you'll get close if not to your original goal, that i'll be a sweet little engine:). I found this CarCraft article and they used 596 heads on a build (360) and had them milled .070 and were all the way down to 51cc's, so i guess it can be done.
I'll add the link, just scroll down below the picture. Good luck to ya!

http://www.carcraft.com/projectbuild/engine_build_rpm_short_block_budget_build/photo_04.html
 
If your willing to rering, hone and bearing job so you can mill the block. If the bore good enough for that you could step up to KB flat top I think kb 167 the block only needs a little off the top for clean up and zero deck it might need balancing with those. But will make easier to get 9:1-10:1 but you see cost quickly rises I still go by what said in your other thread get a low mileage 5.9 magnum I see them here in Canada for $500-$800 you just need rpm intake, your carb, your ignition, your front timing cover and accessories, a car pan and pick can't remember if magnum take 318 or 360 pan, bolt on your exhaust if you got headers and duals your only a cam away from 400+hp, stock cam 300+hp, deal with the torque convert weight.
 
P.M 0u812 about the Thumper cams,he has been doing all the newer mopar builds for Car Craft lately.
 
I have a Thumper cam in my stroker and I like it but I was curious to see what Brian Ou812 had to say about them as well, here is what he told me:

Re: thumper cams

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I've used them in small block Chevy's before, and they make great power with WIDE powerbands.
I guess I don't use them in sb mopars because of the much better HL cams. But if your limited on spring pressure, compression, and/or stock rockers the Thumpr's work great without having an optimum combination.

__________________
Brian Hafliger
IMM Engine & Dyno
www.immengines.com
 
273 thanks for the big help.i think im just gonna mill the heads,maybe hold off on the zero deck,and run it as is,get an rpm intake,what im gonna look for are some magnum heads,sounds like best thing to do,then i can buy some cheap chevy roller rockers,but i have not seen a complete magnum block for sale,or found one anywhere,so that'll have to wait for awhile.- OldmanRick thanks for the link,do i go for the performer rpm,or the rpm airgap?also would an m1 intake be a good manifold,theres one for 90 bucks,and a torker for 50$.. -oh and 412 stroker im glad to hear the thumper is somewhat good for performance,as everyone baggs on me for buying one,saying its not much better than the stock cam,but did he say that about the roller versions,the mother thumpers,or big mothers,as i have the smallest,and hydraulic flat tappet? thanks everyone for answering my questions.
 
As for the torque convertor deal,i was planning a 4 speed swap,as theyre all over craigslist,as cheap as 200$,so i dont want to have to spend any money on my 904 i have now.thanks everyone,let me know about what intake would be the best for my app...
 
7duce swinger said:
As for the torque convertor deal,i was planning a 4 speed swap,as theyre all over craigslist,as cheap as 200$,so i dont want to have to spend any money on my 904 i have now.thanks everyone,let me know about what intake would be the best for my app...
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As far as the Eddy you might as well step up to the RPM air gap. That manifold works well on anything, you could keep it so long you could will it to your grand children. If the M1 is the dual plane that good manifold and a good deal at that price. I would personally stay away from the Torker for your current application.
 
No the m1 is a single plain intake,90 or best offer,is that not a good choice,if not a can try n find an air gap,or an rpm at this months mopar show,thanks for all the help so far.
 
7duce swinger said:
No the m1 is a single plain intake,90 or best offer,is that not a good choice,if not a can try n find an air gap,or an rpm at this months mopar show,thanks for all the help so far.
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I think with your cubes and rear gear the single plane is gonna be way too weak at low rpm's. Not saying it's not worth buying at that price for a future project, but i wouldn't use it here. If you can pick up either Eddy, regular RPM or airgap, used for a deal that's what i'd do.
 
X2 ,with Rick.A duel plane is unbeatable for your combo.Until your compression hits 9.1 true,or you run 3.91s,don't waste the coin.A stockie manifold,(or a performer) will get you close to the 12s ,with a 3.55 ,and a 2000 stall.
 
Okay edelbrock it is.Speaking of gears,is 750$ bucks too much for a rebuilt 3.55 unit (pumpkin only)dont know what case it is,it seems a little high no??
 
So i wiped the pistons off a little bitter,and cleaned the greas off them,idk if my cam is to big or what??,every single piston has signs of both valves hitting on them,all have signs,does this mean my thumper has to much lift? Its .486" intake, and .473" on exhaust,im using stock rockers,how much lift do 360 heads allow before the valves start hitting the pistons?thanks..
 
Would all pistons have the marks,or would only some have signs is what i mean thanks for any replies..
 
7duce swinger said:
So i wiped the pistons off a little bitter,and cleaned the greas off them,idk if my cam is to big or what??,every single piston has signs of both valves hitting on them,all have signs,does this mean my thumper has to much lift? Its .486" intake, and .473" on exhaust,im using stock rockers,how much lift do 360 heads allow before the valves start hitting the pistons?thanks..
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Unless it was degreed in way off or you had a timing chain jump, failure, that cam lift wouldn't be a problem.
You've got all the signs of serious valve float.
 
Darn,well the cam was installed by me and my brother in law,he said it was right on,(hes done tons of cams before)valve float?is that where both valves stay open,is that something that would happen at high rpm's?or is that just messed up timing,chain jumping a tooth?
 
7duce swinger said:
Darn,well the cam was installed by me and my brother in law,he said it was right on,(hes done tons of cams before)valve float?is that where both valves stay open,is that something that would happen at high rpm's?or is that just messed up timing,chain jumping a tooth?
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Valve float occurs at higher rpms where the valve springs are not strong enough to keep the lifter on the lobe after it goes over the nose, kinda like launching them off a jump. When the valves hang open longer then they should you lose power and if the stay open long enough for the piston to get high in the cylinder in relation to them they can touch. It's similar to the chain being off time but the engine will usually run fine at lower rpm's and at higher r's when the valves have to open & close so fast that the problem occurs. A replacement spring that matches your cam will fix the problem assuming that's what caused it.

P.S. your engine ran well before so i believe you had the cam and chain in ok.
 
Thanks,are the pistons still ok to use ,even after better springs,or are they kinda on limp mode now,like maybe its no good,find a different block,or better pistons type of thing?also,the engine ran very well before,and i might add that i never really ran high rpm's since i swapped the cam,only a few steps on it,and starting it for the family,and friends,so could it be from the old cam,idk if the cam i pulled out of it was the original.
 
7duce swinger said:
Thanks,are the pistons still ok to use ,even after better springs,or are they kinda on limp mode now,like maybe its no good,find a different block,or better pistons type of thing?also,the engine ran very well before,and i might add that i never really ran high rpm's since i swapped the cam,only a few steps on it,and starting it for the family,and friends,so could it be from the old cam,idk if the cam i pulled out of it was the original.
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Pictures of a few piston tops would really help so we could see what your seeing.

My thinking is, and others may disagree, that if it was just a kiss the pistons are probably reusable. Anything more than that would be questionable. I would also check the valves, guides and pushrods for any damage or bending.

The bottom line is once you've determined all the components you are going to use you'll need to mock up one head and check your piston to valve clearance to make sure.
 
I dont have a way of posting a picture at this time,the only way i know of would be sending a picture to someones email address from my phone,thats the only way i know of,other wise i cant.-Only one of the pistons touched an intake valve pretty good,all the others are smaller in size,i couldnt even see them before i cleaned the greas off with spray n a rag..also is the piston supposed to have a little bit of a rocking motion,like barely be able to be pushed by hand???
 
To answer your question, yes a slight rocking would be normal. It's just the piston to wall clearence.

Now to the big picture. From the info. you have provided you've got some clearence issues that are only going to compound themselves with the modifications your talking about doing. Head milling, zero decking and possible piston replacement are going to require checking valve lift, pushrod length and intake manifold fitment (milling) and so on.

At this point the only thing i can recommend is find a good reputable machine shop and let them evaluate what you have and what you need. For a durable, good running engine, all these thing have to work together. Just piecing it together is not going to get you where you want to be. It will cost a little more and take more time, but in the end i think you'll be much happier with the results.
 
Thanks OldmanRick,yea im thinking of just selling the block,or even selling it for scrap metal,im in the process of bodywork,so i think the engine can wait for now,just made some metal wanna-be 340 dual scoops,and now i gotta solve the wavy hood problem,im also thinking of doing a rear trunklid,somethin like a 68 charger tail,and i just finished doing my spring relocation,so i now need some wide wheels,(and more money).Im either going to look for a 360,or a magnum 360 somethin thats a better start with,maybe even a bigblock,(i wish i could cram my dads 396/427 combo in there :) )but then theres that part of me that wants to slap myself for thinking about it.thanks for all the help guys,who knows maybe ill stick with my trusty lil teen.. -p.s. my uncle checked the pistons,he says they all just barely touched,so theyre still good,n valves/pushrods are all ok.
 
If you can,keep it running.You stay interested that way.If lo bucking it,a Magnum is a good choice.The truck Magnums are the same long block as the 380 horse crate motor.The cam and valvesprings are the only difference.Hit the yards when you have coin.As for Chevy rats,I grew up on those.Hard to beat, and break on a budget. Good luck.
 
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