EXACTLY why I posted post 45. EXACTLY. "13 in the quarter would be pretty sweet if I can get there and still be streetable"......
You do not 400 HP to get to 13's. Not even CLOSE to 400 hp.
318 build suggestions?
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You do not 400 HP to get to 13's. Not even CLOSE to 400 hp.
I agreed with most of what you basically said if I remember right.
Just took issue that a 318 gonna need 21° more cam, like I pointed out a 400 hp 318 needs about 230° cam so if a 400 hp 360 needs 21° less cam would make it a 209° cam and I don't see to many of those.
Besides the cam degrees, yes a 318 generally needs more rpm to make similar power.
An engine generally doesn't just gain hp at peak hp only, a lot of the time cam heads headers intake carb etc.. Will gain from 2500-4000 rpms and up.
Example.
Blue is a stock 2bbl 360, all the bolt on mods gain from at least 2500 rpms if not lower and within the mods each change increased power from 3200 rpms and higher. Even though the mods moved peak hp higher it also helped basically across the whole powerband especially where your engine gonna be most of the time during a full throttle run. Even though your not spending too much time at peak hp increasing peak hp and rpm was basically a net gain everywhere.
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You might not hate them, but you don't believe they can be made into a performance engine, so close enough, so how can you really help someone build one into something you think is impossible?
You definitely don't need 400 hp to do that.
Build a combo that makes peak power around 5000-5500 and pulls to you shift at 5500-6000 rpms think you'll be happy, which be around a 300-350 hp 318 engine or 350-400 hp 360 etc..
I always had a street cars that would pull to 6k and above. Absolutely loved it, still do as a matter of fact. All three Barracudas do 66 four speed, 67 auto, 68 auto.
He likes to power shift at 3000 rpm, so should you
WHERE IS THE RED X?Short version: Build a 360...
zookgumby
Member
I have a 65 dart GT with a .030 over bore '68 318 with wiseco 10:1 pistons, comp xe274 H cam, dual exhaust (stock exhaust manifolds), dual plane weiand with 600 cfm edelbrock, '73 stock electronic ignition, balanced, high perf valve job, ported heads, carefully timed etc. and it is very fast and still streetable. I also have a dual quad 350 light cammed 64 chevelle, a '41 ford with a pumped 456, and a 13.5 second mustang and it can hang with any of them. The little dart is light and fast and I would estimate about 300 or more horses... a 318 is a good platform IMO. With careful tuning, it will still pull 15" vacuum at idle. (although it took a while to get the right pcv and timing setup).
Ant
Well-Known Member
That's a fair deal, but not the reality for everyone. That's why I gave up looking for a 340 and took whatever I can get for a decent price.
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Newbomb Turk
Well-Known Member
Dale Davies
Well-Known Member
Do not burden yourself with all those whose first response is to build a 360. Nothing wrong with 318 engines. Yes it is easier to get 400HP out of a 360, but sometimes you go with what you have or have available.
What heads are you thinking about, and valve sizes? Aluminium are lighter and not much more cost than getting iron heads reconditioned. The fairly standard 2.02/1.6 valve combination is borderline tight in the proposed 3.97" bore, for shrouding. This not not by much.
Iron heads is a matter of what you can obtain reasonably, considering you will need to go through them and pocket port and port match them. LA heads can have Chev 1.9"1.55" LS valves installed. You will need to have either LS powdered metal guides or bronze guides installed for the 8mm stems. You should be able to use the Chev beehive springs, retainers and locks. This saves weight, and due to the millions built, the parts are cost effective. I would consider 1.6 ratio roller tip rockers for less guide wear.
What are you considering for the cam? A FT cam is less expensive up front, but you must be careful with oil selection to protect the cam and lifters. This means probably no oil changes at the Lube Tube as they will put in what comes out of the hose. One advantage of a FT cam is the valves can be accelerated off the seat quicker than an equivalent roller.
A roller cam system is going to cost up front, but oil selection is not a big concern.
For the displacement of the proposed short block, the LSA should be 104°. 106° would be acceptable. A cam with 220° to 224° intake duration @ 0.050" lift should be a good compromise. For valve lift, I would be looking for 0.500" to 0.550". If you get the exhaust seats and valves ground for 40° instead of 45°, the exhaust blows down at the lower lift more efficiently. With that you can use a single pattern cam for more low RPM torque and fuel economy.
Remember, it costs no more to get the cam ground as the cylinder displacement and cylinder heads want, than an off the shelf cam, and you will get better performance with the cam the rest of the combination wants. The wider LSA cams will tend to aid a smooth idle, at the expense of torque and power, while tending to flatten the torque curve. Yes, Pro-Stock engines are using wide LSA (120°) cams, but the rest of the combination permits/dictates that.
If you want stock appearing the LA heads may be the way to go. Magnum heads would hardly be noticed, while Aluminium heads are easily noted. The Magnum heads are more prone to cracking. A sound set could be fitted with 2.0" LS intake valves.
I hope this gives a bit to think about that helps.
Dale Davies
Well-Known Member
Good recommendation. I would reduce the LSA to 108° or better 106°. Yes a little chop, but the engine will be real crisp.
Where I got highway gears 2.xx:1, I usually get up to 15-20 mph in 1st and then let her rip until 40-45 mph intown so basically 2500-6000 rpm, She still gets up and goes ok from a dead stop. I've been told by a certain someone that 1st is useless on the street traction wise with a 360, but my old BF 245 seem to do ok guess it's the highway gears and 9:1 cr (V/P)
Newbomb Turk
Well-Known Member
Where I got highway gears 2.xx:1, I usually get up to 15-20 mph in 1st and then let her rip until 40-45 mph intown so basically 2500-6000 rpm, She still gets up and goes ok from a dead stop. I've been told by a certain someone that 1st is useless on the street traction wise with a 360, but my old BF 245 seem to do ok guess it's the highway gears and 9:1 cr (V/P)
Yeah, I’ve never understood the “you can’t get more than some retardedly little power number to hook” crowd.
Don’t learn chassis tuning.
Just detune the **** out of the engine so your lack of tuning skills doesn’t get offended.
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Who in their right mind making any amount of real horsepower shifts a 3000 rpm. lol
A decent 360 should make about 380-400 lbs-ft at 3,000 rpms, hp is 57% of torque at that rpm (215-230 hp), so basically 1500-3000 rpms is making 100-230 hp. Any decent 360 @ 3,000 rpms you barely got into it's powerband you haven't even hit peak torque.
A decent 318 @ 3000 rpms 330-350 lbs-ft = 190-200 hp.
Newbomb Turk
Well-Known Member
I do. That’s why I said that those of us who know why we do it, well…we know.
I’ve told people why to do it. But not publicly. I keep it to myself.
i thought you were a 8500 rpm guy.... ??
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