Ok, so I bought a 1-owner '76 Scamp from an old lady earlier this year. I put some big-and-littles on it a couple of weeks ago and will be competing tomorrow at the track for the first time in this car. That being said, everything else is completely stock...right down the to 2 bbl carb. I have a Holley 670 Street Avenger on the way (courtesy of eBay) and was getting ready to order one of those cheapo Crosswind "air gap" intakes when I saw the "can be used on a 318...only if it has 340/360 heads" warning on their website. I've seen this on a few other intakes I was looking at and was wondering what the deal was. Are the intake ports on the cylinder heads too small compared to the intake? Can the heads be ported to match the intake? I was also looking at a Weiand 8022 intake and it didn't mention any of this 340/360 head nonsense. So what gives? Will the Weiand 8022 work on my stock 2bbl-318 heads? I really just want to put a 4bbl carb and intake, a set of headers, dual exhaust, and a slightly thumpy cam in it...for now. Is there an easy way to do this?
Easiest/Cheapest way to a 4bbl 318?
- Thread starter daginsu
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Edelbrock Performer RPM intake would be a good choice. Mine runs real nice. Put a 1" spacer under the carb. this is my 318 mild build performer intake, Mopar 340 grind purple cam, 9:1 CR, 360 heads, stock 340 manifolds. Engine is now forsale as I have a 422 to install.
[ame="http://www.youtube.com/watch?v=0EBEvNxtUUk"]YouTube - 72 Duster 318 burn out[/ame]
[ame="http://www.youtube.com/watch?v=0EBEvNxtUUk"]YouTube - 72 Duster 318 burn out[/ame]
That's kinda what I was thinking. I'm just not sure if the ports are grossly mismatched if the performance is going to suffer. I'm assuming if the intake side of the heads could be ported then this would be a moot point.
I did look at those, but the "Power band" of the Weiand seemed a bit better. The Weiand was Idle-6800 RPM and the Edelbrock was 1500-6500 rpm. Probably not a big deal, but the Edelbrock was one of the intakes that said "Designed for 340-360 c.i.d. Chrysler V8s and 318 c.i.d. engines with 340-360 cylinder heads" on their website, which kind of scared me away from it.
one thing you need to watch out for is ...if you have an automatic trans is the with a new manifold and 4 barrel carb...the kickdown linkage will not fill correctly...
you bought a holley carb...you will need a holley 20-7 adapter ...
you bought a holley carb...you will need a holley 20-7 adapter ...
green1
Well-Known Member
318, 500 cfm
dodgetkboy78
EDELBROCK HEADS SUCK!
Not at all, just a 4bbl wakes the little guy up nice.... Done it too many times in my life for anyone to tell me different.
And yes, for a stock 318, the 670 is too much. Even a mildly warmed 318 runs nice at 500cfm.
BEST INEXPENSIVE 318 MANIFOLD would be the stock cast piece.
rofilel:
Josecuda
Well-Known Member
BEST INEXPENSIVE 318 MANIFOLD would be the stock cast piece.
Best inexpensive aluminum that´ll fit 318 head ports?
dodgetkboy78
EDELBROCK HEADS SUCK!
That would be the performer, or the streetmaster 318............
LXguy
Well-Known Member
Id go with the Edelbrock Performer, LD4b (discontinued- look on Ebay etc), Weiand Stealth or Action Plus. Whatever you can find that's cheap.
With the super low compression stock 318, you need torque/power right off idle.
I ran a 670 street avenger on my 71 318 with an LD4B. Its what I had laying around and it worked fine, and it'll be a better carb for if/when you get a bigger motor or a hotter 318. Its a vacuum secondary, so it'll sort of size itself to the car. I didn't have any problems with mine, and it felt like a whole different motor with the 4 bbl carb. A different slow motor, but much improved.
Exhaust and cam will help, but you *really* need to resist the temptation to get a big cam. Your motor has very low compression and won't work well with something that needs to get wound up to make power. Hughes sells a cam for these engines that is supposed to work well (I haven't tried it). The smallest Lunati might be ok.
Biggest bang for the buck at the track will be gears, converter and tires.
Good luck
Steve
With the super low compression stock 318, you need torque/power right off idle.
I ran a 670 street avenger on my 71 318 with an LD4B. Its what I had laying around and it worked fine, and it'll be a better carb for if/when you get a bigger motor or a hotter 318. Its a vacuum secondary, so it'll sort of size itself to the car. I didn't have any problems with mine, and it felt like a whole different motor with the 4 bbl carb. A different slow motor, but much improved.
Exhaust and cam will help, but you *really* need to resist the temptation to get a big cam. Your motor has very low compression and won't work well with something that needs to get wound up to make power. Hughes sells a cam for these engines that is supposed to work well (I haven't tried it). The smallest Lunati might be ok.
Biggest bang for the buck at the track will be gears, converter and tires.
Good luck
Steve
Easiest and cheapest way is a 2bbl to 4bbl adapter plate and a used Holley 600.
Thanks for all of the input and info everyone. I think I have more questions than ever now .
LX: I briefly looked for an LD4B on eBay and came up with nothing. I also did a Google search and didn't see anything obvious except for the fact that these intakes are pretty highly sought after and are becoming scarce, so I'm thinking the price might be outside of my budget even IF I do find one.
So maybe I should just throw some headers and dual exhaust on the current setup...maybe throw a posi unit in the rearend and just plan to build a mild 360 over the winter. I was really wanting to use the current 318 because it has just under 68,000 miles on it, but maybe that would be counter-productive.
The car is currently very slow, but also very consistent at the track. More consistent than I am anyway ;)
.LX: I briefly looked for an LD4B on eBay and came up with nothing. I also did a Google search and didn't see anything obvious except for the fact that these intakes are pretty highly sought after and are becoming scarce, so I'm thinking the price might be outside of my budget even IF I do find one.
So maybe I should just throw some headers and dual exhaust on the current setup...maybe throw a posi unit in the rearend and just plan to build a mild 360 over the winter. I was really wanting to use the current 318 because it has just under 68,000 miles on it, but maybe that would be counter-productive.
The car is currently very slow, but also very consistent at the track. More consistent than I am anyway ;)
What is the compression on one of these dudes? What's the easiest/cheapest way to raise it?
And last question (hopefully), the research I've done suggests that I have an 8.25 rearend in the car...what's the best way to make sure?
caferacerx
BAND MEMBER
edelbrock standard "performer" intake should be small port and it will fit square bore and spread bore carbs, I also have a weiand stealth that is small port but it is an older one so I am not sure about the new ones and only has square bore mount, a big port 340-360 intake will bolt up but it will not work well due to the difference in port size, you can bolt on a set of big port 340-360 heads but the bigger chamber volume of those bigger port heads will drop your already low 8.? compression down into the 7.? range, welcome to the world of the 318, they are a great engine but can be a bit frustrating to get the right combination of parts to work well, there a lot of really good info about them on here just search 318 in the small block section
caferacerx
BAND MEMBER
8 3/4 has a removable center section that installs from the front 7 1/4 and 8 1/4 both have a cover on the rear, the 8 1/4 looks normal size (pick up, van, mustang) the 7 1/4 looks like a tiny toy rear
one more inexpensive solution for your 318 would be to use a set of 5.2, 5.9 magnum heads they have smaller chambers to boost your compression, bigger ports and valves to increase flow, and you can use an edelbrock air gap or the cheaper chinese knock off crosswind aluminum 4-barrel intake (I use the crosswind with a set of U-PULL IT junk yard heads)
http://www.summitracing.com/parts/DCC-5007477/
one more inexpensive solution for your 318 would be to use a set of 5.2, 5.9 magnum heads they have smaller chambers to boost your compression, bigger ports and valves to increase flow, and you can use an edelbrock air gap or the cheaper chinese knock off crosswind aluminum 4-barrel intake (I use the crosswind with a set of U-PULL IT junk yard heads)
http://www.summitracing.com/parts/DCC-5007477/
Thanks for the info Caferacerx. So if I went with the Magnum 5.2 or 5.9 heads the only problem I would have is making sure I used the correct pushrods?
I was also looking at the Crosswind, but so far the only thing I have purchased is the Holley 670. I just wanted to make sure how all of this is going to play out before I get too deep into it...and drown
I was also looking at the Crosswind, but so far the only thing I have purchased is the Holley 670. I just wanted to make sure how all of this is going to play out before I get too deep into it...and drown
Caferacerx: thanks for the info, that should help me quite a bit. I'm thinking now what I should do is go find an entire 5.9 Magnum (or at least the block and heads) from the nearest Pull-a-Part and just go from there. I could either take the heads off of it and get them freshened up for the 318, or just build the 5.9 and do minimal stuff to the 318 in the meantime.
Thanks for the suggestions!
Thanks for the suggestions!
LXguy
Well-Known Member
I'd guess the actual compression somewhere around 8:1 maybe. My stocker had the pistons down in the hole about .100, and the headers were almost 70cc. Pretty hopeless.
Magnum heads can be a can of worms. First, they like to crack between the seats. Next, you have to change to oil-through lifters and get hollow pushrods. The heads may or may not have to be machined in the pushrod area for the correct clearance with flat tappet camshafts. Valve springs will need to be changed also.
A set of the Indy X heads would be interesting but may be out of your budget. They are a direct bolt on and you could mill them a smidge to really help out the CR.
I went for the 5.9 Magnum swap myself (heads were cracked, went with Iron Rams from Hughes). It is working out well so far, but its been a long and winding road.
A set of '302' castings would be a direct bolt on and should be somewhat affordable. Will help your compression ratio too. They still have the 318 ports and valves though.
I would spend money on chassis parts and put together a plan for getting a bigger motor down the road.
Steve
Magnum heads can be a can of worms. First, they like to crack between the seats. Next, you have to change to oil-through lifters and get hollow pushrods. The heads may or may not have to be machined in the pushrod area for the correct clearance with flat tappet camshafts. Valve springs will need to be changed also.
A set of the Indy X heads would be interesting but may be out of your budget. They are a direct bolt on and you could mill them a smidge to really help out the CR.
I went for the 5.9 Magnum swap myself (heads were cracked, went with Iron Rams from Hughes). It is working out well so far, but its been a long and winding road.
A set of '302' castings would be a direct bolt on and should be somewhat affordable. Will help your compression ratio too. They still have the 318 ports and valves though.
I would spend money on chassis parts and put together a plan for getting a bigger motor down the road.
Steve
Sorry about the double post eariler...didn't seem like it was going to work so I did it again
LXguy: I figured it up and I can get a 5.9 block and heads for about $130 from Pull a Part. This is of course assuming they have one and it appears that there are some potential candidates looking at their website. If I can find a good one maybe this would be a good start for a 360/stroker build later down the road. And if the heads are in decent shape then maybe I can throw them on the 318 in the meantime if it looks like the 360 build might take longer than I can stand to wait.
Does that sound reasonable?
LXguy: I figured it up and I can get a 5.9 block and heads for about $130 from Pull a Part. This is of course assuming they have one and it appears that there are some potential candidates looking at their website. If I can find a good one maybe this would be a good start for a 360/stroker build later down the road. And if the heads are in decent shape then maybe I can throw them on the 318 in the meantime if it looks like the 360 build might take longer than I can stand to wait.
Does that sound reasonable?
On second thought, maybe I should just buy one of these next year with my tax return and bonus money
http://www.summitracing.com/parts/MLL-BPC4080CT/SuggestedParts/?prefilter=1
Anyone ever heard anything about these engines or this company?
http://www.summitracing.com/parts/MLL-BPC4080CT/SuggestedParts/?prefilter=1
Anyone ever heard anything about these engines or this company?
Ok, so based on information I have gathered so far, here is the new plan. I welcome comments and suggestions because I am somewhat close to clueless:
Edelbrock Performer intake (or maybe a Weiand Action Plus), Holley 670 carb, a set of "302" heads that will be gasket matched, Summit G9040 1-5/8" headers and dual exhaust, and assuming I have a 8-1/4" rearend I'll go with the sure grip carrier and probably go ahead and change the rear gears. I was also looking at the Comp XE268H (20-223-3) camshaft with 224/230 dur @ .050 and 0.477/0.48 lift.
Assuming this is what I go with, does anyone see any major problems with this combo? I know the carb might be slightly too large, but I already have it, so I'm going to take my chances.
Any suggestions on the rear gear?
I do not plan on doing anything to the block/pistons/etc or the trans/TC in the near future...is that ok with this combo? My thinking was that if the XE268H cam works ok for now, then I can get a 2,000-2,500 stall TC later and it will still be a decent cam.
I look forward to hearing your opinions/ideas.
Edelbrock Performer intake (or maybe a Weiand Action Plus), Holley 670 carb, a set of "302" heads that will be gasket matched, Summit G9040 1-5/8" headers and dual exhaust, and assuming I have a 8-1/4" rearend I'll go with the sure grip carrier and probably go ahead and change the rear gears. I was also looking at the Comp XE268H (20-223-3) camshaft with 224/230 dur @ .050 and 0.477/0.48 lift.
Assuming this is what I go with, does anyone see any major problems with this combo? I know the carb might be slightly too large, but I already have it, so I'm going to take my chances.
Any suggestions on the rear gear?
I do not plan on doing anything to the block/pistons/etc or the trans/TC in the near future...is that ok with this combo? My thinking was that if the XE268H cam works ok for now, then I can get a 2,000-2,500 stall TC later and it will still be a decent cam.
I look forward to hearing your opinions/ideas.
caferacerx
BAND MEMBER
I would still go with a set of magnum heads over 302's, the bigger port and valve size will allow the engine to breath way better, I like your idea of getting a $130 U-pull it 5.9 magnum and building a stroker motor with a set of INDY X heads, then you could use the stock magnum heads on your 318 with a cam while you build the stroker (just make sure the lifters you get are oil through the pushrod type), the swap is very straight forward and if the heads came off of a running motor they should be fine, and it would be more economical to use the same magnum style air gap or crosswind intake on both motors, I see summit doesnt have the conversion pushrods but they shouldnt be hard to find, and new valve springs are always a good idea when installing a bigger than stock cam
http://www.dippy.org/forum2/index.php/topic,295.0.html
http://www.moparmusclemagazine.com/techarticles/mopp_0409_318_engine_build/index.html
http://www.dippy.org/forum2/index.php/topic,295.0.html
http://www.moparmusclemagazine.com/techarticles/mopp_0409_318_engine_build/index.html
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