I just got my new custom carb & I'm really excited about it!
I put it on the car yesterday & tried it out & was amazed what a difference it made in how this car starts just right out of the box. I've got a video uploading with more info & I'll post a link to it later today when its done doing its thing.
If you've been watching my videos then you know what a hard time I've had with this car over the past year & FINALLY I think I've got some good news to share with you guys for a change.
Here is a link to the carb I'm so happy about. I talk more about it in more detail in the video you'll see in a little while.
Glad you found a carb that works, and the electric choke is a big plus. The hole in the back of the bottom of the carb supplys full manifold vacuum and should connect to a short aluminum line then to a rubber hose with a check valve on it just before going into the power brake booster.
Just because inquiring minds want to know what is the new carb number?
One other question, I thought that if you have a 4 hole manifold that you should use a 4 hole gasket.
Others should speek up and say if I'm correct or wrong.
Glad your a happy camper today and hope to see a video of you driving soon. PG.
Last edited by petes74ttop; 07-08-2009 at 01:33 AM.
Glad you found a carb that works, and the electric choke is a big plus. The hole in the back of the bottom of the carb supplys full manifold vacuum and should connect to a short aluminum line then to a rubber hose with a check valve on it just before going into the power brake booster.
Just because inquiring minds want to know what is the new carb number?
One other question, I thought that if you have a 4 hole manifold that you should use a 4 hole gasket.
Others should speak up and say if I'm correct or wrong.
Glad your a happy camper today and hope to see a video of you driving soon. PG.
The base plate of my other carb is different. On the old one the threaded hole doesn't exist & in its place is a pipe sticking out that connected a rubber hose to a check valve in the valve cover. On the new one this pipe is in the front of the base plate (or at least its the same size & shape) so I flipped the valve cover 180 degrees so that the hose would reach. I hope thats what I was supposed to do there. My old carb didn't have anything under the fuel filter.
Yesterday I got a plug for the brake booster hole but thats before I knew what it was. I can't say it made any real difference. I'll check & see if the brake booster line is somewhere else but I don't remember seeing a line with a check valve.
Basically the only thing Ive done to this carb, from out of the box, is put some plugs on/in unused stuff that didn't exist on the other carb & adjust the idol screw in the front.
This motor is a 2 bolt main not a 4 bolt main so you're probably right about the gasket.
I'll check out the numbers on the carb for decoding & post them up later.
I still have to get a stall converter before I can drive it. That 270H comp cam still doesn't get along very well with the stock trans & just tells it to dig a hole in the drive way & kill the motor when its put in gear, but thats another thread.
I'm going to get a buddy to come over & help me play with the timing a little. I tried doing it by myself yesterday but cranking, getting out, grabbing the light & distributer & getting my eyes to focus before it died proved to be about as difficult as you'd imagine.
Correct me if I'm wrong but shouldn't I be shooting for 12 before? Or is that number Corvette specific & I just need to figure out what this race motor needs?
Also I was told that my exhaust (or lack of anything but headers) would make setting the timing difficult & that an exhaust plays a huge part in timing. I don't understand the logic to this at all. Seems to me that the light is going to flash when it sparks & twisting the distributor changes where the flash says the 0 is on the little numbered thing regardless of what the exhaust is doing. Am I missing something here?
Glad to see (hear) your having some sucess.
To me in the vid it seemed like the timing was off. Also you could have a fouled plug or two, caused by all the troubles you've had in the past. Setting the timing at 12 before will be just about right, but the best way is to use a timing tape on the balancer, and set the timing to 34-36 degrees at 3000 rpm. The headers won't matter much for setting the timing, but you will need to fix them for driving, as you will get alot of backfiring with those exhaust leaks. Don't adjust on the carb very much until the headers are fixed.
1976 & later RQ decode
My numbers are 17085213 1406 HPB
170 - Prefix Code
8 - Decade Produced
5 - 1976-1979 (1705) 8 - 1980's (1708)
5 - Year Produced (1985)
2 - Model
0 - Monojet (1 bbl) Federal standards
1 - Two jet (2 bbl) Federal standards 2 - Quadrajet (4 bbl) Federal standards
3 - Monojet (1 bbl) California standards
4 - Two jet (2 bbl) California standards
5 - Quadrajet (4 bbl) California standards
6 - VariJet (2 bbl) Fed
1 - Division. 0, 1, and 2 all indicate Chevrolet.
4 - Buick
5 - Olds
6,7 - Pontiac
3 - Transmission
Even numbers - Automatic Transmission Odd numbers - Manual Transmission
I believe the next set of numbers indicate the day it was made. I did request an auto for the cruse control hook up. I couldn't figure out how to install the cruise control bar thing but thats not a big deal, I can always figure something out later. Thats not high on my list of priorities at all. It does have a place to hook up the auto trans shift linkage thing-a-ma-bob.
While I was getting the numbers I did notice that the power break booster does in fact have a place for a rubber hose to hook to it & has never had anything on it from the time I got the car (I can tell that by the black spray paint). Looks like that plug will be coming back out & I'll be installing the hose it needs. Is the pipe that screws into the carb hole specificly a carb part to get from NAPA or is this a Lowe's item? I'm sure I can get the hose anywhere but not sure what check valve to get.
Glad to see (hear) your having some sucess.
To me in the vid it seemed like the timing was off. Also you could have a fouled plug or two, caused by all the troubles you've had in the past. Setting the timing at 12 before will be just about right, but the best way is to use a timing tape on the balancer, and set the timing to 34-36 degrees at 3000 rpm. The headers won't matter much for setting the timing, but you will need to fix them for driving, as you will get alot of backfiring with those exhaust leaks. Don't adjust on the carb very much until the headers are fixed.
Glad to see you back with a smile on your face!!
The timing IS off, its pretty much just set a little better than the static timing setting & needs to actually be set. I've got to get another set of hands so that I can play with it a little. I can probably do the 12 degrees but cant do the 3000 RPM until my electrical problems are fixed because my tach is still haunted by the mysterious back feeding phantom ground.
You have a HUGE vacuum leak, and thats due to the the brake booster port in the backside of the carb is left un-plugged, plug it tight and your engine will be able to idle.
You need some fender covers. I could be wrong but doesn't your vacuum advance on your distributor need hooked up?
I keep towels around if I'm going to be working on something for a while but for just a tool or two I'm not worried about.
The distributor that came with the motor was modified so that the advance was welded solid (all out race mod). I changed it out to a functional advance for future fuel economy. Even if it were hooked up, there isn't enough vacuum to make it do anything at idol speeds. The vacuum advance gives a little more advance to the timing at higher RPMs only. I'll probably need it hooked up for the 3000RPM timing when I get to that. (Correction needed if I'm wrong here)
Speaking of hooking it up, where should the new hose connect with this new carb?
So, adding the hose from the carb to the break booster seemed to make it run a little smoother. I've replaced a bunch of lines in the vacuum system & going to just keep on keeping on with the replacements. Unfortunately, the thickness of the outer diameter of the hose I got is causing me problems with replacing stuff. In the center front of the car there are 2 places where 3 hoses plug in & they are stacked very closely. The tiny difference in the outer diameter of the hose makes it imposable to squeeze them in there & forget about getting any kind of water clamp in there also to get a good seal. Am I supposed to have a more specific hose size for this & if so what is it?
At random a buddy of mine stopped by yesterday that has helped me with the car once before & was wondering how the project has been going sense last time. I’ve tried to set the timing & idol speed with the light by myself without success a couple times now. He did it for me purely by ear in about 10 minutes, which I though was a really cool trick. I’m sure I’ll have to do the light later on when I have other things lined out but it sounds darn near perfect as it is. It’s got that snarly rough idol that sounds like its ready to die at any second but somehow it doesn’t, you know, that really cool hot rod sound. (Video of new sound coming soon)
He did something with a foot on the gas & break at the same time where it wouldn’t die & move a few feet & said that without a doubt I do need a stall converter. I figured that anyway so no big surprise but I gotta tell ya the new sound of it is AWESOME!
He’s going to come back in a few days to help me check the lifters because there is a pecking sound that seems to be getting worse over time.
He also has a buddy that has a stall converter for dirt cheep that I might get if it’s the right size. So, lots of good news here!
Have you fixed your tach yet? If not, go out and get a digital timing light that shows your rpm. It sure makes timing easier with one person.
How is the idle in P or N? What rpm?
I was having this problem a while back with my new crate. I was also told the only answer to my problem was a higher stall converter. I would have to set my idle in P around 1100-1200 rpm and then it would slam into D. I couldnt stop in drive or it would bog down and die. My rpm drop was somewhere around 600 from N to D. I installed a 2500 converter and it made a big difference but it was still noticable and the large drop was still there. It turned out to be carb/ignition problems after all.
I think your stock converter stalls at 1800 or somewhere around there. That should still be drivable with your setup. But a higher stall is always a plus for the future
I know you have probably already done this but go over your plugs/wires again just to be sure.
Have you fixed your tach yet? If not, go out and get a digital timing light that shows your rpm. It sure makes timing easier with one person.
How is the idle in P or N? What rpm?
I was having this problem a while back with my new crate. I was also told the only answer to my problem was a higher stall converter. I would have to set my idle in P around 1100-1200 rpm and then it would slam into D. I couldn't stop in drive or it would bog down and die. My rpm drop was somewhere around 600 from N to D. I installed a 2500 converter and it made a big difference but it was still noticeable and the large drop was still there. It turned out to be carb/ignition problems after all.
I think your stock converter stalls at 1800 or somewhere around there. That should still be drivable with your setup. But a higher stall is always a plus for the future
I know you have probably already done this but go over your plugs/wires again just to be sure.
Keep at it
Sean
The tach isn't working yet but the electrical guy just got back in touch with me & said...
I have been wondering what happened to that Vette. I have a couple of things in the works right now, give me a week or so and I'll get in touch with you.
& what I'm going to do is probably take it to him & say "there ya go, good luck!" because I'm done trying & not getting anywhere with it.
My timing light has the twisty knob for setting stuff, I just don't know what I'm doing. It's gotta be another instance of a communication gap between what a book says to do & actually seeing somebody do it once. I run into that a LOT!
The guy I had over here the other day that helped with the timing said that when I add an exhaust that the RPM would drop because of back pressure (as he looked at the duel exhaust propped up in the corner of the garage) however I explained that I'm going to side pipes & he said there probably isn't going to be a huge difference in the RPM then compared to just having the headers & nothing else. There will be some difference, enough to retweek a few things but nothing so significant that I wouldn't still need a new stall. (so he says & I agree) Believe me, I'd love not to have to pull the trans again but if it wont go anywhere I gotta do something.
I will be putting the stall swap off until other options are absolutely exhausted. I know from experience that pulling the trans is going to suck. I'll check again after the electrics are fixed, again when the side pipes are on etc.
That cam will work with a stock stall. You have other issues.
Find and fix any obvious leaks first. That includes exhaust manifolds etc, even if you are going to swap out or fit a new exhaust...do a temp repair.
Try to eliminate a vacuum leak if there is one. To do this, remove all vacuum pipes from the carb and plug the holes.
Then set the timing. Read the timing sticky...lots of info to go through but easy steps to follow.
The carb has to be set up with the timing. Lots of times, people think the timing is out when really the carb is not set up correctly. I know you have had this carb built for your engine so hopefully, setting the timing will show it to be good.
I hope that it will Jotto but my luck doesn't usually go that way. I taped this today so you guys can see what it's currently doing. Don't look at how dirty I am because I'm roofing this week.
OMG the sound in the under car shot right next to the headers is AWESOME! I'm not sure if I feel bad for or envious of, that poor little weed in the driveway LOL.
Your secondary air flap is opening under high throttle / WOT. This will need to be adjusted.
Also, the under car view....do you have a gas leak? Looks like something dripping quite badly from front right area...possibly under fuel pump.
Your getting there. When you put the car in R, you should have your foot on brake. what would happen if, when it was warm you were to up the idle speed just a little, foot on brake and then put in to R? Sounds like your revs are dropping off just a little too much.
How long is it for the engine to be able to run on its own? Seemed like quite a while of feathering the throttle at the start of the vid to keep her going. Most cars should run by themselves, possibly a bit roughly after about 2 mins of no choke on a cold start.
If you have the electric choke wired up, you need to adjust it as you shouldnt need to feather the throttle at all. it should just start and run.
From cold, you need to floor the throttle before turning key to snap the choke closed. release throttle and turn key...she should start right up.
Corvette Store
New Custom Built RQ Carb just $315 (W/video)
