Where did I go wrong? Other than being a cheap ***

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mechanic190

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1980 360 with a reringed bottom end. Stock heads with no work done to them. Stock dual plane intake. Comp 275deh camshaft. Converter only stalls to 2000 before it starts pushing through the brakes. 600 cfm Holley vac secondary. Stock mopar ignition. And 4.10 gears with 29 x 10.5W slicks. Ran a 15.18 today in the heat. First time at a 1/4 mile track. Dropped from a 9.3 1/8 mile to 9.6 in differences in weather and altitude. Budget was little to none when I was building it. Now I'm not impressed and I wanna go faster but budget is still little by little. can't go out and order a set of heads or nothing like that. Maybe $300 bucks a paycheck to blow on her. So the questions is what to buy and in what order. Not caged or anything but I wanna get to the index just before I need to cage her
 
You didn't say what you are running for exhaust, but the most obvious thing I see is that it needs headers and a free-flowing exhaust of 2.5" minimum size. The 600 carb is on the small side. Where is the timing set and what kind of advance curve is in it?
 
600 holley what spring do you have in the vacuum canister?.....
Get the distributor recurved....
 
Don't confuse cheap with broke. you can be both, but most are just the latter of the two...
 
Set of headers and 2 1/2 max! Duel exhaust. Removing weight at your hp level is free effective horse power. Could install .020 head gaskets. Electronic ignition is fairly cheep. Are valve springs matched to cam? Or just stock springs? Good duel plane intake like performer or rpm will reduce weight and build hp. Torque converter is money well spent. Your rear gear is going to want rpm and that will be complimented by a higher stall. 3200 would fit the bill nicely.
 
1980 360 with a reringed bottom end. Stock heads with no work done to them.

What compression ratio? Is it verified? A stock 360 has a compression ratio of a whopping 8:1 or something. Nothing great going on there.

Stock dual plane intake. Comp 275deh camshaft. Converter only stalls to 2000 before it starts pushing through the brakes.

Cam sounds ok for the rest of your heads. Not to big. Converter doesn't sound to bad for that cam. Dual plane works well on these kind of setups.

600 cfm Holley vac secondary. Stock mopar ignition.

Carb sounds ok if it really is just a stock 360 that's been re-ringed. If you start putting bigger cam/head work into it. Then the carb will definitely need updating.

And 4.10 gears with 29 x 10.5W slicks.

Honestly that's a lot of tire to run on your setup. You're not making huge power (no offense). You could go with something shorter and thinner, less rotating mass=better power transmission. Go with bigger tires when you start to have traction issues. 4.10 gears are good. 4.56 would be better if this is going to be a dedicated track car. Make sure to match gear to tire size, so you trap right below max HP.

Ran a 15.18 today in the heat. First time at a 1/4 mile track. Dropped from a 9.3 1/8 mile to 9.6 in differences in weather and altitude. Budget was little to none when I was building it. Now I'm not impressed and I wanna go faster but budget is still little by little. can't go out and order a set of heads or nothing like that. Maybe $300 bucks a paycheck to blow on her. So the questions is what to buy and in what order. Not caged or anything but I wanna get to the index just before I need to cage her

Assuming a car weight of 3-3400 pounds. Your horsepower is in the area of 170-200. Not really a surprise on a stock bottom 360.

It's not so much a question of what to buy. As to what to do. I would do the following in this order:

Get compression up. You want your DCR (dynamic compression ratio) to be in the neighbourhood of 7.5:1 (more if you live at higher altitude). Match your static compression ratio to your cam to get your dynamic compression ratio up. This will greatly improve power, response, well everything really.
Head work. You would be AMAZED what some head work can do on iron heads. Get 2.02 intake valves put in. While they do that get them to clean up the entry into the bowl (greatly increases flow). Mill the heads to reach compression you want. It's not nearly as expensive as a full port job and will give you great power benefits.
Headers. Let it flow baby let it flow. 1-5/8 tubes into a 2-1/2 inch exhaust fits the bill nicely. As others have mentioned. But header's respond best with compression and head work.
Converter. A custom converter is always the best route. BUT in your situation, given your cam and what not. I would honestly think 2,000 is ok. You MIGHT need one after some changes if you're making enough power. But remember, 340's in their heyday had a converter very similar to yours if I recall. If you are looking to run fast enough to require a cage, you will need some serious changes. All of which would require a new converter. I would do the compression/heads/headers first. And see where you end up. If you want more at that point. Well then it's cam, porting, overbore/stroker, intake porting, carb, etc etc. After which you will need a new converter again. So you might wanna hold off till then. But up to you.

As for budget. Don't worry about it man. We all got our limits. Enjoy driving it! That's the fun part.
 
Well, take your cheap *** (lol) and take some of the paycheck to the tool store and get you 3 things......

1-Vacuum gauge
2-Leakdown Tester
3-Compression Gauge

Start there and make sure you have a solid mechanically sealed motor. It's my life`s broken record when I state what's above.

And you ain't no cheap ***. It's calling doing what you can with what you can. You will so enjoy your journey of getting the performance out of the car you want. Looks like fun to me lol....

Report back with those numbers from those tools and it will help others help you on the board....


JW
 
I agree with above, start simple. Also verify TDC on your balancer if not already done. What was the MPH in 1/4? Rpm at the stripe? Was the cam degreed in? What is your fuel system? Also timing, what initial, what total and all in at what rpm? What is the carb jetted at? Before you start throwing parts at it, make sure what you already have is up to task.
A shorter tire would help with the 410 rear, I ran a 26 inch drag radial and 410's, mine would trap at 5800.
 
Whoa 15.8?! ............I've had stock teeners do that.
What gear were you in and what rpm through the traps, what mph,and what was your 60ft. . Sounds like a 2-gear run, with next to no tirespin and not nearly enough torque-multiplication off the start-line.
And most importantly what altitude are you at?
And that cam is probably not helping,at all.
How fast do you want to go?

Imagine you are a young man approaching the prime of your life, and you are a bit of a sprinter. So put yourself in the starter box; with your ankles hobbled to half stride,your arms tied to your side, your lips glued shut,and one nostril plugged. That IMO is a fair comparison of your combo.
The hobbled ankles is your gearing.
The tied up arms is your tranny TC.
The glued-up lips is your exhaust system.
And the one nostril is your heads and carb.

And if you are at 5000ft, nothing but a lotta money will get your car hustling.

I'm not trying to be a dick; I'm just trying to shine a little light on the road ahead. At $150 a week, you might need to save for about 12 to 18 months to get into the low/mid twelves,reliably.
 
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Personally, seems to me there's a 'huge grey line' before we start to throw headers at this thing

Where is the cam degreed?

Where is the timing total and what is the curve?

How do we know what the carb is doing? Could be OK, too lean, to rich, hell..........
 
Well you know I have a hard time cyber spending people's money that's why I suggested on the budget he talked about some headers and just some weight loss and some more time at the track just getting used to the car. I went out on a little bit of a limb as he says he's a mechanic, and I would think that tune up would be the ABCs of what he can do. I'd like a little feedback from the original poster before we make any more suggestions.
Everybody knows how things get on this forum if the original poster doesn't jump back in here and give us some more feedback by the end of the day we'll be talking about the Kung Fu marathon on TV.....
 
The converter is nowhere near a match for the cam and gears.
 
Oh boy! This is the one where David Carradine has a fight with a real Warrior and he pulls his Shaolin priest suit out of his backpack and meditates under a waterfall before they have there what looks like match to the death this is a good one!
 
do it once ! do it right ! I got no problem spending your money. this calls for the 5 year plan. save save save
 
Has open headers on it. Weight loss is damn near done with not much left to lose besides fiberglass. Fuel system is a carter electric pump through half inch fuel line to a regulator set at 6.5 lbs or so. Comp says the cam works with a stock converter so I figured 2000 should be alright with it. Rpm at the stripe is around 4000 rpm in third gear
 
Altitude is 2700 at the track yesterday the corrected alt was over 7000 feet and 135 track temp
 
600 holley what spring do you have in the vacuum canister?.....
Get the distributor recurved....

^^^^ this is good. Lighter spring in vac secondaries and get the initial timing and curve done up right. The ignition curve make a HUGE difference in low end grunt.

Tire are too tall for what you are running, unless you run it like a glide, 1st and 2nd only. That tire will still kill 60' without a BUNCH more converter.

Cam will make power in a 360 to about 5300rpm. If you spin it much more than 5500, it's likely just churning. Shift it short

7000 DA is over a second off from a sea level run, just a guess. Probably a 14.60 or so at sea level.
 
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Yeah I thought something els was amiss here. You should be doing a lot better with your combination assuming it's in good tune. Although your trap speed or I should say your trap RPM is a little low. Again due to what's been said before maybe gear ratio or tire size can improve things but definitely go out on a better day with better air and temperature. Did you say you had lots of experience and this is your first time with this car? Or was this your first time at the quarter mile period ?
oh yeah and one more thing--
Altitude is 2700 at the track yesterday the corrected alt was over 7000 feet and 135 track temp
 
This rice paper is the test. Fragile as the wings of the dragon fly, clinging as the cocoon of the silk worm. When you can walk its length and leave no trace. You will have learned."
 
I just put her together back in May. Ran a couple 1/8 mile passes at 1100 ft. Ran 9.28 as the fastest. Did nothing but change plugs and wires and ran the 1/4 yesterday
 
9.28 in the 1/8 is mid 14's. More gear or a smaller tire should help. That cam is done about 5800 rpm? I would think 5500-5800 rpm at the stripe is what I would shoot for. What was MPH in 1/8 and 1/4?
 
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