i have beeen reading al these forums about the 5a heads 7a heads and such. how do i know what heads i have? i bought a cam from comp cams, part number is 42-413-9, i am having problems with the timing. i also have installed a performer intake, street avenger 570, and flowtech headers. just can't seem to get any power. oh yeah, i have a distributor w/ vacuum advance.
my 87 307 out of a 87 442
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Are you setting the timing with the vacuum line hooked or unhooked?
line should be disconected, and the port has to be plug when setting the timing
Is the vacume advance on a full or part time vacuum port?
Some carbs have both. when you unhook the line at an idle, it should have vacuum. If not, you need to switch where the vacuum line is hooked to.
line should be disconected, and the port has to be plug when setting the timing
Is the vacume advance on a full or part time vacuum port?
Some carbs have both. when you unhook the line at an idle, it should have vacuum. If not, you need to switch where the vacuum line is hooked to.
with it unhooked. do you know anything about the head issue? or if the cam might be to big? if you go to comp cams it's part number 42-413-9.
was realy looking to just freshin up this motor. is this motor worth that?
was realy looking to just freshin up this motor. is this motor worth that?
i know that the heads are clearly marked, but not sure as to where they are marked. Check the forums.
As far as if it is worth it, It all depends on what your going for, IMO theres a fairly large amount of cool factor to having a motor that most ppl would use, and having it produce more power then most cars
Your cam is deffinitly not to big, it is a daily driver cam.
Also, have you done anything with your pistons?
Have you checked your compresions? (no compresion=no power)
IMO if you swap out your pistons, stick to flat tops, have your head and maybe your block shaved. it will give you a better surface for your headgasket to seal up to, and will rasie your compression slightly and it shouldnt give you any clearence issues.
As far as if it is worth it, It all depends on what your going for, IMO theres a fairly large amount of cool factor to having a motor that most ppl would use, and having it produce more power then most cars
Your cam is deffinitly not to big, it is a daily driver cam.
Also, have you done anything with your pistons?
Have you checked your compresions? (no compresion=no power)
IMO if you swap out your pistons, stick to flat tops, have your head and maybe your block shaved. it will give you a better surface for your headgasket to seal up to, and will rasie your compression slightly and it shouldnt give you any clearence issues.
your first concern is easy to fix.....
driver side : look at the head near the first spark plug hole ,you have a number cast . what is it?
driver side : look at the head near the first spark plug hole ,you have a number cast . what is it?
Honestly unless you are determined to keep the original vin# the 307 is just not worth the money it takes to make it faster when compared to droping in a stock or modified olds 350/403. There is a guy on oldspower that has one running low 15s but. The 350/403 is the same externally. To make a 307 fast takes ported early heads pistons cam probably a decked block its just not economical compared to more power for the same or less money in a 350/403. I have my vin 9 307 on the garage floor for the next owner so as to retain any restoration value. I used a Cadillac 500 but I wanted a docile pump gas 11 second car.
You have two options, pull the motor and junk it, swap with a 350 or 403
or
reinstall the old cam or find one that doesn't have so much lift.
There is no vacuum advance, it is controlled by the computer unless you are running an HEI from a 74-79 Olds.
If the 307 is out of an 87 442 then it's a roller motor with 7A heads and you may have the wrong type of cam for it. The lobe design is different for a roller motor with roller lifters and it looks like the cam you chose has too much lift for a 307 to begin with since the port design is very small, much smaller than a 5A head 307 from a Hurst Olds.
83-85 VIN9 - 5A heads .440 lift, Mechanical Lifters
86-87 VIN9 -7A heads, .440 lift, Roller Lifters, smaller swirl port design heads, intake and exhaust manifolds. Motor is basically useless doing any upgrade. An Edelbrock intake will not work, ports are to large.
or
reinstall the old cam or find one that doesn't have so much lift.
There is no vacuum advance, it is controlled by the computer unless you are running an HEI from a 74-79 Olds.
If the 307 is out of an 87 442 then it's a roller motor with 7A heads and you may have the wrong type of cam for it. The lobe design is different for a roller motor with roller lifters and it looks like the cam you chose has too much lift for a 307 to begin with since the port design is very small, much smaller than a 5A head 307 from a Hurst Olds.
83-85 VIN9 - 5A heads .440 lift, Mechanical Lifters
86-87 VIN9 -7A heads, .440 lift, Roller Lifters, smaller swirl port design heads, intake and exhaust manifolds. Motor is basically useless doing any upgrade. An Edelbrock intake will not work, ports are to large.
I'm not sure of your level of expertise and don't mean to offend or insult anyone, so please just take this as a loose guide line. The number for the head is right next to the number one spark plug on the drivers side, you may have to remove your alternator bracket and degrease the area to see it. As far as your set up everyone is right you need to have a 70's HEI distributor (the one with the large cap and the coil in it) just about every Olds from 74 to 79 or 80 has one. Comps could have came in, in 80 or 81 I'm not sure. It will have a vacuum advance on one side and 3 wires on the other side that go to the cap. I usually get mine from big old cars like Olds 88's or station wagons because there's at least one in every junkyard. Your carb is sized about right so that shouldn't be a problem, however your cam is way to big. You need to make sure that you have a roller cam. Also look into something more like a towing cam with a power band from like 1500-5500. Most of these cars came with 2:50 factory gears. Keep in mind that during normal driving its rare you'll have it up over 2000 rpm especially if you kept your overdrive trans, you want a motor that makes power where you need it. If your motor makes all its power from 3000-7000rpm the car will be a slug and be horrible to drive until you hit that 3000 mark which would be rare with 250 or 308 gears. Then if you were to step up to like 410 or 456's to work with your power band every time you take it out you'll have it buzzing through the roof the whole time you drive it, I don't know if you intend to cruise around in it but 4000 rpm at 60 isn't fun. I would also run true dual exhausts from the header back with 2.5 inch inside diameter pipe if you don't have them already. Unfortunately the 307 just doesn't make much power but with your set up and the few recommendations I just gave you it could be a decent performing car. Personally I would go wit ha 350 or 403 you'd make a lot more power but I understand working with what you've got. You also might want to check out the Olds FAQ at http://www.442.com/oldsfaq/oldsfaq.htm that will also help you out. I'm not sure If I missed anything and feel free to correct me on anything if I am wrong, I don't want to be giving bad advice. Good luck with your build.
That cam is not as big as everyone thinks.
The listed .505 lift is with 1.6 rockers (do the math)
But unless he switched the rockers, He should be running 1.5 rockers giving a lift of .474, plus that duration is kinda short (at least compared to what i like) (rockers based on the fact that every olds i know of came with 1.5 rockers)
With a good flowing exhaust you would be surprised at how it could run.
Which brings me to something, if the exhaust is restricting the motor to much it will not let the motor breath.
Now im not saying that it will produce mass amounts of power, but it will run damn good compared to stock.
P.S. A note from comp cams on that cam: "Daily driver, strong torque, smooth idle, rpm range 1000-5000"
With a description like that, how "big" can it be?
The listed .505 lift is with 1.6 rockers (do the math)
But unless he switched the rockers, He should be running 1.5 rockers giving a lift of .474, plus that duration is kinda short (at least compared to what i like) (rockers based on the fact that every olds i know of came with 1.5 rockers)
With a good flowing exhaust you would be surprised at how it could run.
Which brings me to something, if the exhaust is restricting the motor to much it will not let the motor breath.
Now im not saying that it will produce mass amounts of power, but it will run damn good compared to stock.
P.S. A note from comp cams on that cam: "Daily driver, strong torque, smooth idle, rpm range 1000-5000"
With a description like that, how "big" can it be?
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