Would like to get some more oomph from my 318

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I run cheep headman long tubes and worried about crushing them..

my car sits at factory ride height and they have NEVER touched pavement...ever...

It was a ***** to get the driver side in tho...
 
Do the rear axle first.
Get your ignition tuned in as I didn't see a vacuum advance in your pics.
You might be happy with just those changes.
 
Guys
I have to disagree on the lower trans ratios
When you go to those, you increase the powerband requirement of the engine, by a like amount. A teener with a 236 cam and no compression just won't pull when it hits second gear, and worse in third. If you are gonna build a one gear car then fine.
Here are the numbers 2.45-1.45-1.00 the splits are 59% and 69%
With a 236* cam, the power peak might not arrive until what? say 5650
Well with the stock tranny the 1-2 shift might have to be 7100, to drop in at 4189 for a powerband of 2911, centered at 5645. The 2-3 shift rpm, to be centered at 5660 would need to be at 6700, to drop in at 4623, for a powerband requirement of 2077
Now lets work it out for the wide ratio set.The ratios are 2.74-1.54-1.00 and the splits are 56% and 65%
So to center the shift at 5650, the 1-2 shift rpm would need to be 7250, to drop in at 4060, for a powerband requirement of 3190, to be centered at 5655. The 2-3 shift could be at 6850, to drop in at 4453, for a powerband of 2397, centered at 5652.
To recap
the stock ratio needs a powerband of 2911 and 2077
The wide ratio set needs ................3190 and 2397
Averaging them out the wide ratio needs about 12% more, which is about the same as the ratio increase; 2.74/2.45 = plus 11.8%
So I see two problems, the 236 cam is waaaaay too big and, that's a huge powerband requirement.
So right-off, this teener is sunk.
You need to analyze your driving requirement, to get your cruising speed into the poweband, and to heck with what happens at the line. Then pull cam out til the torque is there and then put some TC into it so it can spin the tires.To do otherwise is to build a dragracer, and hope for the best.
I know this sounds ridiculous, but check it out.
Say most of your driving is done at 35 mph. Ok you will want a reasonably comfortable cruise rpm, and when it kicks down into 1st, you will want the engine to be in a happy place.You will want the closest ratio tranny you can find, so that the powerband can be narrow and the peak power reached very quickly, so you can get into the next gear and back into the powerband. Unfortunately the closest ratio we are stuck with is the stocker.So lets say you picked a more reasonable cam like in the range of 210 to 220, or something that brings the power peak, down to 5000 this will outshift first at 6300, to drop in at 3717, for a powerband of 2583, centered at 5009 So the rpm in first at 35 mph needs to be at least around 3717. So with 25.5 tires, and a 2.45 low gear, this works out to a rear gear of 3.28s, and puts you at the bottom of the powerband. If you are racing to 50mph, this will keep you in first all the way to 5304rpm, and 60 will be 6365, still in first
Now lets get back to the 3.28s
This is gonna suck from a standstill,right. Now hold on a sec. For starters we have here a torque cam, so it's gonna pull pretty hard, and we got 25.5 inch tires, not 28s.And of course you are gonna need a TC. So stick a 2800 in there and call it done. At 2800 that teener is gonna be putting out plenty of torque.
Lets say this teener puts out 130 ftlbs @ 2800, through 3.28s and a 2.45. That would be 1045 ftlbs into the rear axles. Stock it might have putout 100 @ 1600 into 2.76s which is 676 ft lbs. So its up 54% in torque into the rear axles. I....... think...... it's....... going..........to ........spin.
You coulda done the same with the 2.74 low and 2.93 gears. The overall gear ratio to hit 60 at 6365 is nearly identical. The problem comes at the racetrack, and when you shift into the next higher gear.
Now in the beginning OP wanted to track the car and pick up a nice ET. Well the ET and the MPH will definitely be better with the close ratio gears. Unfortunately, the 3.28s will make this a two-gear car, and the ET will suck. But the 3.28s will make it nearly a perfect 2-gear car.5400 will make 86 mph. 98 will need 6153rpm. The wide ratio trans will need 6534rpm to hit 98, almost 400 more rpm
What all these numbers show is that you better not be buying an off-the-shelf cam. You will absolutely need a custom cam, to cover that wide powerband. A 110LDA won't do it.
So analyze your needs and do some math.
 
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First off, you have a really nice looking car . The six pack hood you are considering will make it look even cooler. Anyways... I see a lot of things have been discussed here. My two cents, more converter. 236 at .050 cam in a 318 needs more than a 2800 stall. I would go right to a good 10 inch or even 9.5 inch converter. Even a 318 with a cam ten degrees smaller than yours would benefit from having more stall speed. Of course there are things you can do to the engine to improve the bottom end performance but you are still working with only 318 cubic inches . It's not going to be a torque monster. IMO, for a small engined car to be fast , it needs some combination of : rpm, forced induction/nos or light weight. Assuming a 3500 lb weight, you should only need about 280 fwhp to get in the 13s like you want. But you need to be well into your powerband when you leave the line, and have traction of course. Notice in the link that I'm providing, that the engine's torque peak is at around 4100 . At the lowest rpm tested(3000) it is down 50 lb-ft. If that engine was installed in a car, the difference in acceleration between a 3000 flash and a 4000 flash stall would be huge. And this particular engine has a shorter duration can than yours.318 Small Block Build - How To - Hot Rod Magazine
 
Junkyard Jewel 318 Power Curves

RPM....Torque HP... Torque HP....Torque HP
3,000 334.9 191.3 354.1 202.3 349.1 199.4
3,500 360.7 240.4 378.2 252.0 380.7 253.7
4,000 376.6 286.8 402.3 306.4 401.5 305.8 Start of powerband for TF(1st gear)
4,100 379.3 296.1 402.4 314.1 401.6 313.5
4,500 374.0 320.4 402.5 344.9 400.1 342.8
4,600 374.0 327.6 403.1 353.0 400.6 350.9
4,700 373.5 334.2 400.6 358.4 408.0 365.1
5,000 363.9 346.4 389.7 371.0 402.0 382.7
5,500 344.0 360.2 368.3 385.7 386.5 404.8 center of TF powerband
5,900 331.1 372.0 347.1 390.0 361.4 406.0
6,000 328.3 375.0 344.0 393.0 353.8 404.2
6,100 319.4 371.0 339.2 394.0 347.8 404.0
6800 376.6 286.8 402.3 306.4 401.5 305.8 est'ed end of TF powerband(1st)

This engine beautifully illustrates my thinking. It would make a great dragrace engine.
But they stopped the test way too soon to determine the shiftrpm. I took a wild guess and estimated that by 6800 the power had fallen down to 305.8 .So with a TF the 1-2 split is 59%. Shifting at 6800 the Rs drop in at 4012, for a powerband of 2788, centered at 5406. Notice the highlighted figures.Shifting this way will put the maximum average hp down.
Notice the powerband doesn't start until 4000 rpm. (I don't see a 4000TC in a streeter).This 4000 is 33 mph with 3.73s. These gears will hiway cruise at 3122 with 25.6 tires.So say you do stick a 3500 in there. Until you hit 33mph,you are still way below the powerband.
In order to make this work on the street with a TF, we,or I,would like the powerband to start a lot lower. 3.73s,is the highest I would be comfortable with, for hiway cruising. And 6800 with 3.73s is 56mph(1st). I would want to be well into the powerband at 30 mph.With 3.73s, that would be around 3600rpm. The powerband of this engine is at least 1000 rpm too high.
Or the engine is just too small.
Or you are gonna have to sacrifice hi-way useage.
Sacrificing the 3.73s, for 4.30s say( I mean it's a race engine, one might as well have race gears), will put the engine at [email protected] mph;now yer cooking.The 3500TC will now have only to pull from zero mph to 28.76.I see that as very doable.But you can see that with a 3500TC it will be putting down just 254 hp from stopped to 25mph. Hmmmmmm
Unfortunately 6800 will only get you 48.9 mph(1st), so you are gonna have to shift before 65, the posted speed limit.And when you do,the Rs drop back to 4000, and you get to climb the hill again. 65 will be 5350rpm, a good place to be for sure.So now it's working ...............as a weekend warrior.
65mph is 3689rpm.
And 6300 with 4.30s will get you 111mph. It's a dragcar
Streetable,sorta... Weekend warrior,probably...dragcar,yes...Streeter?Not to me.

Anyway that's my thinking.All criticism welcome....
 
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Well AJ, there are plenty of street cars with 4000 stall converters. Sure they might not be for everybody but they are streetable enough for many of us. I have two cars that I switch off for daily driving duty. One is a 73 RR, mild 400, old MP 175 converter that flashes to about 2800 and 2.76 gears. Other car is a 68 Satellite, 440, 292 .501 Comp cam , old Torker, 750 DP, 3.23 gears. This car has a 9.5 inch Dynamic converter built for the car with the knowledge that it was going to be street driven. This converter flashes to about 4500. This converter might feel a little loose to some but I'm used to it. It has been in the car since about 2003 , gets driven a lot, both in town and on the highway, and hasn't burned up the tranny yet. Of course a good cooler is a must. One thing your calculations don't take into account is that a looser converter helps shift recovery. I typically shift at 5800 and it drops back to about 4500. converter stall rpm and shift recovery rpm..... | Unlawfl's Race & Engine Tech | Moparts Forums
 
Let the torque converter do its job and put more oomph into the torque band.
I always advance my cams 5 degrees with an offset cam key, and enjoy the improved torque, but never go to the strip, either, so I can't say much about effect on ETs.
I do have enough torque for easily controllable wheel slip on takeoff at 1/3 throttle on my 340 with stock converter.
 
AJ/FormS I agree that that low 1st and 2nd isn't the best option but it if the OP is only gonna run 3.55 gears the lower trans gears are better than nothing especially since it's a 99% street car.
 
Running the 2.74 low-gear is no problem at all, so long as the engine is set up for the powerband they require.
Say you put a cam in there that power-peaks around 5000.And you want to run the 2.74-1.54-1.00 ratio. The splits are 56% and 65%. It's a streeter so let's only care about the 1-2 split.
First gear cannot go to 65 mph, with 3.55s and 25.5 tires.That would be 8346rpm in 2.74. In 1.54 2nd it would be 4691. So lets gear it to hit 65 at 5400 ;400 over peak, in second. This will get the most out of the teener, she can give.Well doing the math, this means 2.30 rear gear. So there is no optimizing this 2.74 to show well at zero to 65. But it's ok, the 2.45 low will need 2.57s , so there's no optimizing that either.
But let's go with your idea of 3.55s and a 2.74 low. With these numbers, 65 will be 4691 in 2nd.So now it looks like a pretty good deal. It would have been better to topout at 300 to 400 over the 5000 peak but 309 under isn't so bad. That is until you meet the guy who does peak out at 5300/5400.He will pull right on by you.
Easy solution right? 3.73s will get you 4928. You see where this is going right? The right gear is actually 4.10s: which will get you 5417rpm, in 1.54-2nd. We're done right? Not so fast.We still have to work with the 56% 1-2 split.
-Ok to center the powerband at 5000 with this split, will require a shift rpm of 6400, to drop in at 3584, for a powerband of 2816,centered at 4992,close enough.So to optimize this combo requires 4.10s, and superwide powerband of 2816 rpm and a 1-2 shift at 6400 with a medium sized cam to peak at 5000rpm. and a TC at about 3584 stall.Do you see the difficulty this presents to a streeter?It's gonna need quite a cam and quite a top end.
-Lets work it out for the close ratio 2.45-1.45-1.00 tranny.We'll keep everything else the same. So now the 1-2 shift can occur at 6200, to drop in at 3658, for a powerband of 2542, centered at 4929,close enough.
The powerband requirement is 274 rpm less. This means you can tighten up the LDA and make a few more ponies, to go quicker on the same 4.10s and now shifting 200 rpm lower.The penalty, to be fair is the loss of 11.8% ratio at the line, which might be made up in the now 3658 TC requirement. If not then surely by the tighter LDA.But honestly very few times as a streeter does one need more than 4.1 x 2.45 =10.05 starter gear, with a 3600 TC.
-But here's the best part; When you kick it down at 35mph into 2.45 first, the Rs will be 4641, while with the 2.74 first it would be 5190, almost 200 rpm past the rpm of peak power. Cruise rpm in second at 35 would obviously also be lower.
-But here's the catch. The cam I picked, peaks at 5000, right? If you pick a smaller cam, every thing changes; ev-reee-thing. Everything except the ratio of the powerbands. The wide-ratio tranny will always require a wider LDA cam, to cover the wider powerband requirement.
-There is only one way around this; to make Zero to 65 just one gear.Then it don't matter a hoot what the splits are. Unfortunately to go 65 @5400 requires an overall gear ratio of 6.294, Which would require a huge amount of crank-torque to pull from a standstill, with either low gear ratio. This is not NA street-teener territory. But if you are willing to put a 6000 rpm of peak power cam in there, and hit 65 @6400, then the overall ratio goes to 7.46. This is doable with 2.45 x 3.04s or 2.74 x 2.72s. Yer still not gonna show well with a 3600TC. So to conclude, a teener needs two gears to hit 65, and show well. So back to the 4.10s
 
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Haha thanks guys. Yeah lots of stuff over my head. Will do the gears and probably some Sanderson shorty headers first and go from there.
 
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