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Old 04-04-2011, 04:28 PM
 
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To get back on the topic, magnaflow makes a nice high flow cat as well as dynomax. No matter how perfect you tune the car, it's going to stink without cats.
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Old 04-04-2011, 06:36 PM
 
Location: Vancouver, B.C., Canada
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Quote:
Originally Posted by Boo2lowkey View Post
GTOlover the tach was $80. I wanting to replace the small oil pressure and water temp gauge under the dash to a unit that will be easier to read out and have everything displayed all in one unit. If its pancake enough and the same size dia. of the clock gauge in the dash I will try to install it in there, if not it will go on the center console.

I want both streetable and some performance, the crate motor was built to have 440hp at the crank. The name for it back then by the builder was a Camel Hump 383 stroker. Dart cast iron heads. I paid $4000 in 2001. None of the stuff came with it work with this motor. The Carter 650cfm, holley manuel pump, and vacuum distributer. I will try to adjust the air to gas mixture this weekend giving it more air. Changing the carb isnot an option at this point unless this carb burns out.

? how will the electric choke work if the butterflies has to be wide open to start the car and keep it running.
sorry if I came of harsh but being 22 and since it is such an old car which is cool but to keep it maintained is expensive.

since it will be a constant struggle of fixing one part then it will need something else since it is a 38 year old car.

I would ask fleet or merc63 about owning, maintaning and restoring 70's cars they know about the upkeep on interior and exterior parts and wear and tear items plus issues like rust becomes a problem. I mean with your engine issue and tranny having a rear main seal leaking it could cost a bit to fix.


I say that because your current engine that you overfilled with too much oil and drove it on the freeway at high RPMs for a long period of time and many miles, till it came out the crank case breather tube and covered the underside of the car and it that it overheated is concern. lots of oil causes lots of blow-by. I would do a compression check if I were you to check and see whats up since it could have some bad rings.

a bad vacuum leak can also cause excessive blowby as the discharge from the pump into the engine block can be increased to the point where it is pressurized.
Could be a very simple fix could be a rebuild

My theory with what little info I have from you is that you have a great big cam with great big valves and you may not be pulling enough vacuum to suck in the fuel. THEORY ONLY. try covering the carb top with your hand while someone else starts it and see if it will idle then if it does you may need to rejet to a bigger size jet and or metering needles on thec arb also make sure your firing order is correct and check fuel pump pressure too anyways goodluck dude

that is about all I really now to help you with seeing it in person and I am only a backyard mechanic so someone else who is a licensed mechanic or has ben tweeking carbs before I was born may have a few better ideas

Last edited by GTOlover; 04-04-2011 at 06:46 PM..
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Old 04-04-2011, 07:21 PM
 
Location: Earth
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Quote:
Originally Posted by Boo2lowkey View Post
the guy who built the engine said to use 20/50 performance oil according to his specs. I lost the spec but I do know I have double springs, roller rockers and a high pin setup.
If you "need" to run 20W-50, then either you live at the equator or you have excessive bearing clearances and this is the band aid for them.


Quote:
Originally Posted by GTOlover View Post
wow 6800 on a 383 you he would would need some big heads to make power at those RPMs. atleast a inexpensive aluminum head like the DART Pro 1's 215 cc intake port. Drop a little coin getting them mildly ported and they will outflow AFR's and Brodix heads and still be several hundred cheaper.
I wouldn't think the Pro 1's would outrun the AFR's but maybe?

For sure you'd need big heads and a big cam to not be out of breath at 6800 rpms.

My point was that a 750 cfm isn't really needed on a 383 stroker. But then again what's the #1 hot rodder mistake? Yep overcarbing.

Quote:
Originally Posted by Boo2lowkey View Post

? how will the electric choke work if the butterflies has to be wide open to start the car and keep it running.
Provided you have the electric choke hooked up to a 12 vdc source that is only live when the ignition is in the RUN position, the coil inside the cap on the carb makes the choke plate shut.

One thing I forgot to ask....do you have your vacuum advance on the distributor hooked up to the ported side of the carb? The ported side is under the throttle plate usually on the front someone. When you're sitting at idle, it should have a vacuum on it when you run your finger across it. Hook the vacuum advance on your distributor here....it basically adds a little more timing when idling to burn off the excess hydrocarbons that you end up on your clothes.
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Old 04-04-2011, 07:51 PM
 
Location: Vancouver, B.C., Canada
10,715 posts, read 22,321,366 times
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Quote:
Originally Posted by Deez Nuttz View Post
If you "need" to run 20W-50, then either you live at the equator or you have excessive bearing clearances and this is the band aid for them.




I wouldn't think the Pro 1's would outrun the AFR's but maybe?

For sure you'd need big heads and a big cam to not be out of breath at 6800 rpms.

My point was that a 750 cfm isn't really needed on a 383 stroker. But then again what's the #1 hot rodder mistake? Yep overcarbing.



Provided you have the electric choke hooked up to a 12 vdc source that is only live when the ignition is in the RUN position, the coil inside the cap on the carb makes the choke plate shut.

One thing I forgot to ask....do you have your vacuum advance on the distributor hooked up to the ported side of the carb? The ported side is under the throttle plate usually on the front someone. When you're sitting at idle, it should have a vacuum on it when you run your finger across it. Hook the vacuum advance on your distributor here....it basically adds a little more timing when idling to burn off the excess hydrocarbons that you end up on your clothes.
totally agree also over camming alot get aggressive grinds for the "sound" not the perfomance and it is kinda funny since it sounds like a 10 second race car but it is a stock IROC-Z with a 305 or a mild modded mustang

alot go out and buy a racing intake manifold like the Edelbrock's "Super Victor" series and run a 23 Degree Racing Cylinder Head on their SBC but want a daily driven street car that will be in stop and go traffic more than WOT at the track.


Deez I bet you must seen some interesting set ups and mods that are just over kill since you are into G-body turbo GN's and regals

Last edited by GTOlover; 04-04-2011 at 08:09 PM..
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Old 04-05-2011, 05:17 AM
 
Location: Earth
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Quote:
Originally Posted by GTOlover View Post

Deez I bet you must seen some interesting set ups and mods that are just over kill since you are into G-body turbo GN's and regals
LOL many times. And I'm guilty of a few of them too.

But I've grown up and stopped doing what I was doing and read up on them. Then came to a conclusion that sometimes bigger isn't always better.

And it's not just with me either. I've known people that were all into the "rumpita rumpita" cams, 780 cfm Holleys on 350's, you name it. Same people when they get out of their 20's and on to their 30's and 40's decide "yeah this wasn't a wise idea" and actually convert back to what it used to be/what it should have been.

Once I took a sbc with nothing more than a set of camel humps (engine was built early 80's) and decided to do an intake swap from a stock ported Q jet intake to a Edelbrock Performer RPM intake. Because I was given a free 600 cfm Holley that worked, and I didn't want a Q-jet on there anymore. I picked the intake because it was rated 1500-6500 rpm. Also b/c I wanted an aluminum intake.

Then my uncle was getting a new crate 350 to replace the 6 cyl in his van and wanted the Q jet intake I removed. I thought "now why would you want that old thing?" Turns out he was once a gear head too, but was past all that and preferred a stock piece over an aftermarket piece. Me personally if I were him I would have just bought a performer intake and called it a day. Or maybe he just wanted the old intake because it was free?

Anyways soon after the said 600 Holley came off and I bolted on a 670 Holley. I thought I was cool as ****. But then I didn't find much of a performance increase. Add tot hat this 350 was mated to a TH350 with a stock converter and the rear gears are a *gasp* 2.73. So it has decent acceleration but it's still a bit of a pooch.

And yet here I installed an intake such as an RPM b/c I was going to race it and run it up the rpms. But w/o the gears to do it, it's almost useless. I guess you could say at the time i was planning to just buy the best I could.

So now soon, that 670 Holley (which the floats like to stick BTW) is coming off and an Edelbrock carb is going on. Why? Well as I have learned I have too much carb for it now, plus the floats stick, it's been problematic, and the car really isn't a race car it's a street car. Plus similar to the OP, this car has the tendancy to stink up your clothes, but then again Holleys are known to run rich b/c they're a performance carb.

Oh yeah....I won't go into how it seems when you change one thing on a car, you have to change everything else to make it work.
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Old 04-05-2011, 09:39 AM
 
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Converter will do nothing but clog up the exhaust. Your problems with the carb. A 750 is way too much carb for a 350. Get yourself something in the 600-650 range and have it installed and tuned by someone that knows what they are doing. As for fuel pressure. You should be closer to 6-8 not 14.

I too have a 72 Monte with a 402 BBC and mine runs nice and clean. She's a little rich on start up but clears up nicely once she's warm.
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Old 04-05-2011, 04:59 PM
 
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Quote:
Originally Posted by johna01374 View Post
As for fuel pressure. You should be closer to 6-8 not 14.

I too have a 72 Monte with a 402 BBC and mine runs nice and clean. She's a little rich on start up but clears up nicely once she's warm.
When I swap out the holley 110 gph pump to a mr gasket 105 gph I left the holley regulator on which was set at 9 psi. I got around the block before the carb was starving for fuel. It stalled on me in front of my garage. I build up enough fuel got her in installed the regulator that came with. I set it to 14psi just to drive it around the block a few times to see if it will starve the carb. I will adjust it back down to 9 psi this weekend. I have a coworker who going to help me get this carb adjusted right. He have a full blown out Cuda he drag with and built.

The Magnaflow catback 2.5'' exhaust system came in today. To my Suprise it prebent the exact same as existing exhaust. It should be an easy installed just have to cut the flange and collectors and go from there. The existing exhaust is 2'' tubing all the way through that was squeeze down in the area under the floor pans down to 1.5''. I have no Ideal why was it done that way on the stock motor. I had this car for 10 years now and just getting around to changing the exhaust. I should gain back a few ponies on this install.
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Old 04-05-2011, 08:34 PM
 
Location: Vancouver, B.C., Canada
10,715 posts, read 22,321,366 times
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Quote:
Originally Posted by Boo2lowkey View Post
When I swap out the holley 110 gph pump to a mr gasket 105 gph I left the holley regulator on which was set at 9 psi. I got around the block before the carb was starving for fuel. It stalled on me in front of my garage. I build up enough fuel got her in installed the regulator that came with. I set it to 14psi just to drive it around the block a few times to see if it will starve the carb. I will adjust it back down to 9 psi this weekend. I have a coworker who going to help me get this carb adjusted right. He have a full blown out Cuda he drag with and built.

The Magnaflow catback 2.5'' exhaust system came in today. To my Suprise it prebent the exact same as existing exhaust. It should be an easy installed just have to cut the flange and collectors and go from there. The existing exhaust is 2'' tubing all the way through that was squeeze down in the area under the floor pans down to 1.5''. I have no Ideal why was it done that way on the stock motor. I had this car for 10 years now and just getting around to changing the exhaust. I should gain back a few ponies on this install.
wow 2.5" is still on the small side a full 3" mandrel bent with a off-road x-pipe and full length headers would let the motor breath . I find SBC run great on a larger exhaust system almost the bigger you go the better within reason unlike a Small block ford which likes a bit of back pressure but even then a aftermarket cat back dual exhaust on a ford 5.0EFI most people go for a full 2.75" system.
I think the cutoff is nearer to 350/375 hp for 2.5", 3" for 400HP and up .

But yeah from a 1.5" pinch point to a full Magnaflow catback that is 2.5" I think there will be a huge diffrence in flow. also you will need to retune your carb after the install.

I would suggest you get a SBC performance book such as
1. Building The Pro-Stock small block by Bill Jenkens
2. Power Secrets by Smokey Yunick
3. How to hot rod the small block Chevy
4. How to build Horsepower by David Vizard
5. Performance with economy by David vizard

The first 3 really should be in every chevy guy's bookshelf. They are older books but really have some great stuff. The Smokey Yunick book is a little more universal, and the Bill Jenkins really covers the more specific hardcore small block stuff. The Jenkins book may be hard to find, while power secrets and how to hot rod the small block chevy can be found fairly easy.

anyways what type of budget do yuo have in mind I bet a few people here could steer you in a good direction for a easy perfomace build on a limited budget.

one thing that is overlooked but adds no power but adds some noticeable grunt is putting in a aftermarket 4.11 posi I am assuming you have either a 10-bolt or 12 bolt differential if you have a weak 10 bolt a used 12 bolt from the wrecks and a Auburn or eaton Performance Differentials

Last edited by GTOlover; 04-05-2011 at 08:53 PM..
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Old 04-06-2011, 04:57 AM
 
Location: Earth
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His probably has a 10 bolt unless someone changed it to a 12 bolt, however the 10 bolts they started using in '72 were the corporate 8.5's and they were almost as strong as a 12 bolt. Just look under at the bottom of the housing and see if there's any ears sticking out under it.

Compare to this chart below:


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Old 04-06-2011, 07:53 AM
 
861 posts, read 2,292,772 times
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Quote:
Originally Posted by Boo2lowkey View Post
When I swap out the holley 110 gph pump to a mr gasket 105 gph I left the holley regulator on which was set at 9 psi. I got around the block before the carb was starving for fuel. It stalled on me in front of my garage. I build up enough fuel got her in installed the regulator that came with. I set it to 14psi just to drive it around the block a few times to see if it will starve the carb. I will adjust it back down to 9 psi this weekend. I have a coworker who going to help me get this carb adjusted right. He have a full blown out Cuda he drag with and built.

The Magnaflow catback 2.5'' exhaust system came in today. To my Surprise it prebent the exact same as existing exhaust. It should be an easy installed just have to cut the flange and collectors and go from there. The existing exhaust is 2'' tubing all the way through that was squeeze down in the area under the floor pans down to 1.5''. I have no Ideal why was it done that way on the stock motor. I had this car for 10 years now and just getting around to changing the exhaust. I should gain back a few ponies on this install.
I've only had my car for a few months but mine also has some mickey mouse exhaust shop system on it that's 2 inch squash bend so the bends are closer to 1.5. It's really a hacked together system and I'm swapping in a 2.5 in mandrel bent Summit system and a set of 1-3/4 headers.

2.5 inch is more than enough flow for up to about 500HP naturally aspirated and going 3 inch will gain nothing but weight and could lose torque which is something these big heavy cars need. If you don't have headers I'd seriosly recommend you swap them on. Installing them on the small block is a piece of cake in a Monte as there is a ton of room.

Getting back to the carb tuning. I think you're going to find a problem somewhere else in the setup. Maybe a filter is clogged or something inside the carb is wrong. 14 psi is unheard of on a carbed motor. Most cars run 4 the 6 psi and really hot strip cars run 6 to 8 typically. 14 is drowning the motor. Does the car blow black smoke out the pipes? I would suggest you not even attempt to drive it until this problem is fixed. You could wash nown the cylinder walls which would require a rebuild. Also might want to change the oil.

Post up a couple picks of Monte. I'd like to see it. Here's mine.
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