Anyone have a technical question, or need technical advice, about carbureting a DeLorean?
Bill Robertson
#5939
Anyone have a technical question, or need technical advice, about carbureting a DeLorean?
Bill Robertson
#5939
After I pull the car out of storage, I'm going to need to see how to adjust the choke. It was moody about how it would engage. It the choke wouldn't operate on cold start. It would wait till I was about 1/2 miles down the road, engage and unless I pounded the piss out of the accelerator, it wouldn't disengage. It didn't matter because one I stopped at the very next stop-light the choke would hang up again.
I just wound up disconnecting the choke and having the car run VERY rough until it warms up. So basically I'm operating without a choke.
just saw this and thought it might be intersting for you carb-fans.
http://www.velocetoday.com/wp-conten...rel-webers.jpg
Is that in an Alpine?
I like my carb because it is pretty.
I do have to say I like the look of your carb setup; nice and open, and lots of room. Almost looks like it could have been factory.
You need this for increased prettiness...
http://store.delorean.com/p-6043-lab...tructions.aspx
I've got a body shop that should be calling you in a few days for a lot of parts. Throw one in and I'll be sure to buy you a burger at DCS.
Peugot 604
Thanks. It does look factory except for the plugged injector holes. When I get around to it I am going to do some sanding and painting to the fiberglass in the engine bay.
The engine cover looks extremely bowed up in the center, is that due to the air cleaner clearance? I saw one that had a hole cut out in the cover for that very reason, looked good and no doubt gave it a cooler intake charge.
Hello, I'd like to know the intake port sizes, volume of port as well as the same dimensions on the stock CIS manifold runners would be nice too, and exhaust port sizes of the stock PRV.
My plan, two threes and multiply crossed over 3 into 1 headers....... just looking to fully optimize what is there while I acquire heads and other bits to get serious about finding all the HP and torque the stock bumpstick can accommodate.
It sure seems to me that there must be an easy 25 horses to be had over the stock configuration, if not 40.
If this trail has already been blazed, in whole or in part, I'd be quite appreciative of any knowledge you can share.
I also plan to fully control a higher output ignition's timing curve.
BTW... my factory manual seemingly fails to specify the connecting rod length. Scaling the line drawing seems to indicate nearly 2:1. Could I also get confirmation on the connecting rod length? Thanks for any help you can offer.
Here ya go (page 9):
http://dl.dropbox.com/u/13720563/DeL..._21-Hybrid.pdf
Thank you for the info and that is a much nicer manual than the Delorean Workshop manual. Assuming the Volvo engine has the same connecting rod length, 2:1 it is.
I noted that the Volvo pistons are shown with slight popups whereas the factory Delorean manual seems to illustrate dished pistons for it's 8.8:1 CR. If the Delorean uses dished pistons, do you know the volume of the dish? If it uses popups, do you know it's negative volume?
Is the Delorean PRV the same as the Volvo B28?
However, I'm still seeking port dimensions and volume if anyone knows. I'd prefer to do my homework, make sure I have all needed materials on hand and be ready to fab prior to taking it apart and having it inoperative.
I don't think this one will need very large carbs. I also looked at a available header for the Delorean. My first impression was that the primaries were too large and short for a 6500 rpm redline engine that peaks under 6000 rpm. I'm a bit more inclined to believe this now that I know the internal geometry for sure. I just showed the Crabman and he seems to also agree.
I really want excellent BSFC numbers along with my fatter torque band and more horsepower. I hate not getting every last bang for each drop of dino juice.
The DeLorean uses a B28F.
Sorry I don't know the details at that level for the engine (My head is full of US muscle cars ;-) but there are several here that do...hopefully someone will chime in.
FWIW- I like your approach (homework, probing, questioning, ...) and suggest that if you are not going to keep the K-Jet fuel system, check out the EFI threads here -- At least throw the idea in your bag of ideas, and shake it up, before you choose ;-)
EDIT: You may want to start your own project thread
Thank you again for your help and your suggestions are noted!
The choice has already been made for me, the car is already with one lonely carburetor that does not please my eye or seat of the pants internal dyno.
I've been told many times I should have a stainless car since I specialize in the white metals and have built several largely stainless and ti motorcycles. I build them to go fast and it would seem that I prefer starting with mules wearing flip flops as opposed to thoroughbreds in nikes. Most likely it's really a case of starting with what is affordable and on hand.
It would seem the planets were in proper alignment for me to be honored with Delorean ownership and I'm happy with what I got even though several aspects of it could better. It's perfect for my purposes.
I'm quite competent with the various forms of Bosch FI, especially CIS, as one of my daily drivers is a tweaked 245 that will do 130mph and change, returns 35 mpg at 80mph and will rev to just a tick south of 8,000 rpm. However, I did not get all the CIS system and I'm certain I will make this dog hunt without it.
I think I'll start a general engine constraints thread and maybe see if many or all of the basic tuning dimensions can be gathered into one place for future tuners. If I find them on any of the various Volvo forums (which seems highly likely) I'll bring them here.
It would be interesting to know the primary and collector dimensions of the currently offered headers available.
An aside, I noticed Lingfelter has a DMC-12 featured on his site. I haven't spoken to him or worked with him in years. The last time was in the early 90's screwing together some of his fine components to make a 215 mph Vette. I wonder if he's graced a Delorean with his very masterful brilliance. Do you know? I don't see anything on the net that indicates he's done a Delorean supercar yet. I have him on my list of people to call this week.
btw.... where is the registry so I can check into this car's history? I surely have no desire to type any factual info that may offend anyone.
Do you have any recommendations for Volvo sites which seem inhabited with any land speed racers or other types of serious gear heads?
If you're really into engine modding, I'd suggest looking up the specs for the B28E engine. Compression ratio was 9.5:1 if I recall correctly. If you can get the specs for that camshaft profile, valve size and porting, you will have a really nicely-breathing PRV which can suck up as much fuel as your jets will provide.
Thanks!
Does the stock DMC engine use domed or dished pistons? I really can't tell from the Factory Service manual although they do look to be drawn as dished while the Volvo B27/28 manual shows domes. I'm not sure if their illustration may have likely been of one of the 10:1 engines listed in the same manual.
I like the idea of smaller ports, valves and induction for this particular engine, does the B28E have larger ports and valves?
Any hard numbers are appreciated, I'll root them out one way or the other.
My preliminary studies have had me thinking if I were going to get very serious, warming up a later 90's 24V would be a smart move. I'm sure I could be wrong and some other variant of this engine may be better. I'm content, for now, with the stocker.
Would you think the same header would work well on both the odd fire and split pin versions of this engine? I personally don't think so.
I have never taken one of these engines apart, but I have sent you the e-mail address of someone who has. He should be able to answer all of your questions, or point you to the appropriate literature.
By the way, the 24v version is hard to find in the U.S., but here's hoping you get lucky. FYI, the camshaft is fitted from the other end, so if you plan on installing different camshafts in the 24v PRV, do it before the engine is in the car. ;)
Edit: Have you started a new thread about building up the engine? This thread is for carburetor questions, and there are people on here more knowledgeable about the engine in general than David and I are who may be able to help you out, but they won't be watching this space since it is in the carburetor subsection and most carb users haven't modded the engine in the ways that you are talking about.
Thank you very kindly, sir!
I'm not doing the engine thing yet, I've too many already apart in my shop and I like the engine in this one just fine!
Have you any thoughts on a smooth bore butter fly carb minimum diameter to make 180 horsepower, using IR and six throats?
Do you know if the stock runners will flow enough to make 180 horsepower?
I think they just might and I'd like to know the maximum they are able to flow, without being touched.
I noticed a plenum with runners cast integral on ebay that looks very much different than what came on mine.
http://www.ebay.com/itm/160793546372...WAX:IT&vxp=mtr
Mine does not look like this. Do two styles exist? Could you point me to a picture of the other style if so and when where they changed?
Mine has the upper rectangular vessels, a type of molded plastic, on each side, remove-able and the lower runners "spigot'd" so that they are coupled to the upper non-metal boxes via rubber hoses clamped onto the three spigots at the bottom of the boxes. Maybe my manifold is from something else. Heck, maybe the engine is as well. I suppose I should find out if this engine is a factory PRV for the DMC.
Other than this deviation and the carb in place of all the CIS stuff, it appears to be a stock DMC engine.
I like it better than the ebay stock piece as it leaves me the option of connecting carbs on their ~ 4.5" centers, or removing the "lower manifold/runners" and screwing them directly to the heads.
I'll take it completely apart once I start fabbing up my carb setup and snap some pix.
Does a engine chart exist for the purpose of identifying these engines via their casting and/or stamped numbers and where are they located?
Unless that's some bizarrely specific undocumented motor, that sounds like anything BUT a factory manifold. All that I've ever heard was that the factory cars all came with the manifold you linked to on ebay. (Martin Gutkowski would know a lot more about PRV variations than I, however, and could probably tell you exactly what car it came from).
Can you post a picture? I'm having a hard time visualizing.
Did you happen to buy a $6k DMC with blue bumpers?
The cross-ram intake manifold you found on eBay is what came from the factory. Martin Gutkowski in the UK occasionally has an intake manifold for sale, sourced from an EFI-equipped version of the same engine, which has a much larger throttle body, so it obviously breathes quite well. If he has one, you might contact him, because that EFI intake manifold will be impossible to find locally.
180 HP is no problem for a stock DeLorean PRV. The transmission can handle it, too, so you don't have to worry (assuming you have a 5-speed).
No, I did not happen to buy "a 6K DMC with blue bumpers".
However, I have that same lower runners and it has 48mm throttle butterflies. The runners do indeed accept CIS injectors. I'm not aware of any electric injectors small enough to go into the bores provided.
I also have the air plate and fuel distributor assembly along with the injectors. I've yet to check their numbers to see if they are DMC.
Do you know what that manifold is? What size throttle butterflies does the stock DMC CIS have?
I'm certain it is CIS and not L-Jet or later.
Oh, what do you know to be the HP and torque limits of the automatic and what fails first? Second if that's addressed and at what numbers then?
OK. The going theory on that car was that the intake manifold was not made of metal, and since it was the first one I'd heard of, I had to ask. :-)
I believe the information you seek is in the Volvo manuals for the B28F engine (assuming your car has the original engine in it!). As has been said before, pictures would be immensely useful to anyone trying to help you.
cooperation and communication are the cornerstones of civilization......
48mm butterflies......... stock DMC bores?
Engine and trans ID numbers exact location?
Intake and exhaust port dimensions as found in stock DMC heads?
I'll accept that maybe nobody has cc'd the ports, or if so, not inclined to publish the numbers, but, the bore sizes?
Dished or domed pistons in the DMC stocker?
Has anyone compiled a comprehensive Delorean registry that is viewable online or otherwise?
I'd appreciate the help and sharing, I'm not so much concerned exactly what the runners are for now. Maybe later but, probably not.
Do you seriously expect us to have such esoteric information committed to memory? Most of us hop in our cars and drive them; we do not build racing cars.
A Workshop Manual costs about as much as a decent haircut. If you choose not to buy one, then you will have to wait until one of us has the free time to go and look all of this information up for you, so be patient.
I expect and demand nothing from anyone and own a factory manual. I've looked at the Volvo manual too. Thank you very much.
Sorry, I thought this was a carburetor sub-section of the CUSTOM DELOREAN section. My guess is it would be kinda hard to advise about custom carb setups without knowing some of the answers. I know if MY NAME was on this section, I'd know the answers!
Further be it for me to think some here may actually have an engine or two open with parts laying around.
Good luck with your custom carb section. I'll not intrude again.
See you later, Bill.
P.S. - I did not name the thread. If I had, I would have named it "Q&A about carbureting a stock DeLorean."
Honestly can't decide if Earl is a troll or for real. :confused:
carburetors and DeLoreans
Here is Bill Robertson's e-mail address: [email protected]
Bill is a friend of mine in North Carolina who has tons of Volvo literature at his disposal and should be able to give you any specs on the PRV engine that you might possibly need while constructing your carb setup. He also owns two carbureted DeLoreans so he knows a lot about this alternative fuel delivery system.
Best regards.
Farrar Hudkins
#2613
This Bill you pointed me to in your kind PM?
Look Mr Hudkins, you don't know me from Adam. What I can assure you is that it's very likely I've forgotten more about tuning engines than you'll ever know. When you see a Delorean with a header tuned for what is actually there and carbs far more capable than what your pal is certain has no equal, you'll know I've been there and I'm certainly not pimping barbaric motorcraft carbs, or named Bill.
Just so you learn something from this, IR for this engine, with it's very soft camshaft and port tuning that takes advantage of the very long rod:stroke ratio while avoiding beating the shit out of the air plate and regulator, will perform very well with uncharacteristically small bores, especially with an intelligently designed header having appropriately sized primaries and an effective collector.
I'll even be kind and share some of the numbers.....
34-38mm's
1 3/8 OD by 32-34" requiring multiple crossovers to keep a very tight and long collector end from having a traffic jam
Have you ever seen such an exhaust?
"Ask David and Farrar: Technical Questions and Advice About Carbureting a DeLorean"
Should this have actually been titled, "Post Here for a Continuation of the Same Dead Horse Motocraft 5200 Trick"?
I'm really a nice guy and will help anyone who is respectful, but, I don't suffer people talking about my haircut very well.
I also admit when I simply don't know the answers or am out of my league if my silence doesn't suffice. I damned sure don't talk down to strangers just because I don't know the topic.
Good Day.
Why are you publishing someone's email address in a public forum and attacking Farrar?
Abuse is easy to throw around on the Internet. It's also easy to shrug off. I find it hard to believe that a grown man would have such problems with a simple case of mistaken identity, especially since he uses the screen name of a fictional character from a cancelled TV show and never signs any of his posts. Nonetheless, I seem to have irritated him. OK, but since his purpose in coming here seems to have been simply to brag about his own skill and ask a bunch of questions that would prove how much more knowledgeable he is than the rest of us, I, frankly, could give a shit.
I am still ready to help, to the best of my ability, anyone who would like information about carbureting a DeLorean. I freely admit that I only know one method of doing so, which involves leaving the engine alone and replacing only the fuel system. I am no Bill Robertson, but I never will be. Where my knowledge falls short, I will point in the direction of where knowledge lies, be it in a book, a Google search, or another person. Just because my name is in the title of this thread does not mean that I am some sort of PRV or hot-rodding guru. I do not know where that assertion came from, but it sounds suspiciously like Bill's "Oh, aren't YOU the carb guru now?" which he has used to abuse me whenever I have had a question or some uncertainty since he was banned from here.
Perhaps my name should be taken off of this thread. I may not know everything, but I studied carburetor operation before I changed fuel delivery systems, and my DeLorean has run a carburetor for four years and I believe that I have picked up some knowledge along the way.
Or I am an ignoramus and an asshole. I will let you all decide for yourselves, since I don't care what anyone thinks of me anymore.
[Insert Steve saying "Farrar sucks" here.]