Inliners International Forums General Discussion Blown and Injected snowman4839 turbo build

I have a sunpro boost/vacuum gauge hooked to the large manifold vacuum port on my carb. I looked it up and it reads vacuum in inches of Hg (same unit as power valves) and boost in psi. So since it reads vacuum in inches of Hg, when it reads 10.5 vacuum on the gauge, that's when the power valve opens and my wideband backs that up because it richens the mix by about .3-.5 anywhere under 10.5 vacuum on the gauge.
So... there is no need to convert any units to anything else. The gauge reads in a usable vacuum unit.

I would suggest to borrow another vacuum gauge to compare because your engine cannot produce 26" @ idle.

MBHD

I agree, hard to believe 26" at idle. Compare to another gauge.

My engine is about 15-17 " at idle. 12-13 at cruise. Tom

Snowman,
When you get your fuel system up to par and can get into boost for a prolonged time you will be too lean at 13.5 to 1. You should be about 11.0 to 1 to be safe with your setup. To run this A/F ratio you will be too rich for normal driving with a 10.5 power valve.

About half of your fuel should come through the power valve, this is the reason for the late opening power valve.

Harry

high vacuum can be had at higher than stock idle speeds (1000 RPM) gauge is probably o.k.

Try this, at 60 mpg release gas pedal and allow it to go to idle position and you probably will see elevated vacuum readings too due to higer than stock rpm level.

Get butterfly off of the transfer slot and position butterfly so it dont let vacuum get to transfer slot. Let the carb do its job Then adjust mixture screws to get nice stock style idle speed setting (probably 1-1/2 turns each), idle speeds should not be 1000 rpms- absolutely no need for these excessive idle speeds that is just asking for run-on during the nice warm Memphis summers this will also prolong the life of the throw-out bearing when sitting at red light holding the clutch down.

The transfer slot's soul duty is to help furnish additional fuel to engine as engine is in transition between the idle circuit and the main metering circuit- dont use it for idling-thats what the idle circuit is for. and the accellerator pump's duty is to provide extra fuel when throttle is abruptly applied temporarly interrupting the drawing of fuel thru the main metering system. reworking the accellerator pump is covering up the real proble

Knowing a "crapload" about the carb's circuits is not the same as UNDERSTANDING what causes what.

define idle (at what idle rpm?) try test above-what vac readings do you see?

I see no other practical way of determining the relationship of the throttle butterfly to the transfer slot than a visual inspection of the carb viewed from the bottom. Merely backing down the idle speed by way of the linkage adjustment is not reliable. Backing down idle speed from 1000 to 750 by this method does not insure that the transition slot is now covered and that the manifold vacuum is now present to only the idle circuit. Only a visual inspection can establish this fact accurately.

If you have another carburetor of the same type (matching tag is best), the linkage angle vs. throttle disc angle vs. transfer slot exposure should be very close (at least close enough to tell you it's bad) - without taking the setup apart.

agreed, but if it takes a week to find another one, four bolts, a fuel line and an etc., or two would be time well spent

Well it starts up at about 650rpm and after it warms up (since there is not choke) and levels off at about 1000rpm even. I understand that is a little high but anything lower than that gives me hard starting. I'll try to play with it sometime.

I'm really not crazy though. Slowly rolling into the throttle (so that the accelerator pump isn't really necessary), I stare at my gauge as I'm accelerating (and getting closer and closer to full throttle). It stays at about 13.0-13.5 up until I hit 10" of vacuum. Then I get about an 11.3 anywhere under 10" of vacuum until it gets into boost which slowly rises back up to low 13s. I know I still need to drill it out a little more to get it into the 12s or high 11s under boost.
EDIT: I cruise at about 18-20" of vacuum and if I let off the gas going fast, it bottoms out the gauge at 30"+ of vacuum.

Just got some money for an intercooler and I should be looking at getting the fuel system installed soon now that I have all the parts for it.
Any suggestions on the intercooler? Are air-to-water intercoolers worth the extra money and effort to setup? I had been reading a few of the other threads on here and I liked the intercoolers that had outlets on the same side. 2.5" or 3"? carb hat is a 4" and outlet of turbo is 2.5". I have plenty of couplers to make it all work.
I was just thinking something like this and just having a muffler shop bend me a bunch of pipe 2.5" to connect it up. http://www.ebay.com/itm/Intercooler-27x1...#ht_6343wt_1392

If I had an intercooler like this, would I be able to put it back up to 15psi if I got the carb down into the low 12s or high 11s under boost? Also since the intercooler would create a denser air charge, would it actually give me more power at 15psi than it did without the intercooler as well as giving me better detonation prevention?

[b]A cooler intake charge is always better than a hot intake charge of air, yes, it reduces your chances of detonation.

With my methanol injection running on my truck, I see 59 degrees F intake temperature & I am currently running 25 PSI of boost pressure, how does that sound for super chillen?

MBHD

Ok then. Well here's a 3" intercooler with a pretty big intercooler so that's probably what I'm getting unless you have objections. It has an outlet on each side so it'd have to be a big loop fro the intake side to the front of the radiator to the distributor side back over the valve cover to the turbo hat. Someone on here posted pictures of something like that when I was first starting this project. http://www.ebay.com/itm/BLK-UNIVERSAL-AL...#ht_2851wt_1159

According to the lambda ratio, keeping the ratio under boost at high 11s or low 12s gives about an extra 20% fuel strictly to absorb heat. It seems like that would ruin efficiency terribly. Or does the amount of boost you can add because of the cooler temps outweigh the lower efficiency? I mean why not just richen it further to low 10s? I also don't want to drill it out too much and then have to buy a new metering block.

I understand methanol injection cools things down a lot but don't syclones/typhoons have water/air intercoolers stock?

Just some FYI, that intercooler is a tube & fin design, for the most part, they cost less,weigh less,perform about the same as a bar & plate design, but the tube & fin design is most susceptible to getting damaged from road debree , basically saying, they get damaged easier than a bar & plate design, your call which one you choose.

I think your best bet would be to buy an kit like you posted, looks OK to me if you like that kit, but search some more & post up the ones you are looking @ & I am sure we can help you out w/a intercooler kit.
Things to look for on tubing, use thick wall tubing, don't get the thin wall tubing, sure it's lighter, but it crushes easy watch out!
Hoses, they have 2 layer 3 layer 4 layer, silicone hoses, get the one w/the most layers.
Some of the "T" bolt clamps can be a bit cheesey, do some research.
If you look @ my plumbing, there are no 90 degree bends, just smooth & somewhat gentle 45's.

The only time you want to run your A/F ratio in the low 10's & even high 9's is when you are running a methanol injection system,, my tune is not perfect, but the engine in my Sy likes about 10.3 A/F ratio w/methanol injection.
In an ideal world you could run that lean of 11's to 12 A/F ratio, we are saying for you to run high 10's & low low 11's is to be safe & less likely to detonate, stop reading that garbage info before you blow up your engine, & listen to guys that actually run ,dyno tune there cars for the street & track, talk w/people when you go to a track, go to the turbo buick forum & read up on there A/F ratios, I can tell you this, they do not run as lean as you are, & when they do run that lean, by mistake, or plugged injector, bad fuel pump etc,,, bad things happen like blowing up a piston/s, head gasket/s, torch the top of the block etc.

Here are some pics you might have seen.







Yes, Syclones & Typhoons do have air to water intercoolers,,, do you have a question?
MBHD

Check to see if you can find that same intercooler kit minus the 90* sweeps.
Unless you are planning on cutting them to fit.
You should be able to find the exact same one with 70* bends that replace the 90*'s.

As previously stated anytime it makes a hard turn your restricting flow.

It took me a while till I found a piping package without 90*'s
This is the one I'm looking at for mine: http://www.ebay.com/itm/250842398542?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
When I purchase it I will inquire if I can swap out the 90* silicon elbows for 45* elbows.
If not I will purchase 4 extra 45* elbows.

Good luck,
Stu

"super chillen" as in children,temperature, or of natives of Chile Loop a round or two through the cab and eliminate the use of power draining a/c while doin' the chariot race down to the hamburger stand with your 3.55s.

Dont forget 3.55's & OD, that's overdrive, keep the rpms down, save fuel.
The A/C clutch disengages when @ W.O.T. woot, woot.

MBHD

those clutches dont disengage at wot or woot on all cars (more generation gap). but the cold intake pipe would be a good substitute when they do

well I might have to put off the intercooler for a little while because of some other unexpected expenses.

Took it for a drive tonight and I noticed that I really had a noticably higher amount of power when the engine was cold. I know it's not good to run an engine hard when it's not warmed up but I mean the feeling I got when I pushed it at 10psi when the engine was cold was about the same feeling I got when I had it at 15psi. It was really surprising.
Is this just because the whole engine is still cool and it's helping keep the intake charge cooler? That's the only thing I can think of.

The engine's operating temp right now is 210F. Do I need a cooler thermostat? Seems like it'd be 180 or 170 or something. It still ran great at those temps.

When you install your intercooler, it will run a lot better, even when your engine is cold, but even more so.

On a nice cold night w/an intercooler on, you will notice a big power increase as the inlet temps will be low, almost as good as running methanol, well, not quite that good.

Too bad, you can't get your intercooler, did you install your new alternate fuel system yet?

MBHD

T.T.T.

Does anyone know if any 500cfm holley 2bbl parts are interchangeable with a 350cfm holley 2bbl? I was thinking since I already have most of the parts need for the turbo (nitrophyl float and drilled metering block and bowl) and since they're the same model, couldn't I just buy a 350cfm main body and 350cfm base plate and then just put the other parts I have on there to save myself some money. Anyone know if that'd work? I'm really sick of this carb and I've played with most every setting and the squinter size is just ridiculous but I still have that bog if I hit the throttle quickly.

and no. I've just been really busy ever since christmas so I haven't had a chance to work on the fuel system.

Snowman,

I do not understand why you would want to run a 350 Carb?
I believe it will cause a restriction for what power level you are wanting to get out of your 250.

If you cannot get the 500 carb tuned correct, I do not see having/switching to another carb is going to do some magic trick & all the sudden work correctly.

I do not think you have done all you can do to your carb, as far as tweaking it to run correctly.
It's OK to say, I give up & it's beyond your limits, just find someone who can tweak it for you.

MBHD

Well that's not what I'm saying at all. I've just read that people have a horrid time getting this 500cfm carbs to run correctly on street cars. Everywhere I've read has said that these were made for circle track racing where the cars are almost always at full throttle.

Another thing I was thinking is that it was simply too much carb for the engine. I mean the stock monojet was like a 190cfm carb. It just seems to be a huge jump without doing the valvetrain.

Dont quote me, but I do not think there is much difference @ all between a 500 2BBL carb & a 350 2BBL Holley.

I think Harry Turbo6 is/was using 500CFM carbs, could ask him for more info.
He has been blowing throgh 2BBl carbs for a long time. Pay attension to what he has to say about them.

Maybe call the places that do mods for blow through carbs & get there input.

I am not sure what size 2BBL carb I have but, I believe it's a 350 CFM 2BBL if you want to buy it. I am not going to do anything w/it.

MBHD

Snowman,
Look up Boucher's thread, or contact him and see what carb he used. He may have some tuning tricks that may help you. I don't recall hearing him discuss having much (if any) trouble tuning his carb.
Just a thought.

Boucher used a 350 carb & he had said he drilled out a passage too big. He had already stated things to do & not to do.

MBHD

A quote from Frenchtown FLYER
"The 500 does have a propensity to bog on fast throttle opening. I used one on a 302 V8 for a while and finally got it to perform well on accels with the right combination of pump cam, pump squirter, carb heat, inlet air heat, and power valve.

If after fooling with all these variables it still bogs have the metering block surfaces fly cut. As built they are unmachined and sometimes not flat which leads to aeration in the pump squirter circuit.

Look at two I flycut. Note that after a .005 cleanup cut they still do not clean up completely. The pump squirter transfer boss is often the last area to clean up. Also notice the carb on the left and how “spongy” the metal looks. Pray you don’t have one like that.

The 350 and 500 share some components but base plates, metering blocks, booster design and venturii sizes differ. If the bowl designs are the same (cathedral or side-fill) then floats and inlet needles can be interchanged"


MBHD

I've noticed recently I've had a good bit more blow-by coming out of the valve cover vents than normal. It still runs fine like always and I still have good oil pressure but it's pretty concerning. If I take off the breathers for the valve cover, you can see white puffs of air come out with each rotation of the engine whereas before the blow-by used to just slowly waft out if at all. It also fills up the foam on the breathers with oil pretty fast to the point where it actually starts blowing oil through the breathers onto the outside of the valve covers.

Is this just because the turbo has been beating up my piston rings and they're starting to lose compression and let blow by through? Instead of re-ringing it, is there much else I can do? I'll do a compression test later to see if the rings are the problem but what else would cause this? Would leaky turbo seals cause pressure to escape from the turbine or compressor into the oil drain and pressurize the crank case? That's about my only other thought.

Sound like bad news. The turbo does not beat up the pistons/ rings. Lean, hot mixtures with too much timing cause detonation. You may have cracked a piston ring land or broke a ring. Maybe more than 1 piston is affected.
Does it miss?

Do you have any video of it running/ driving? Show us what it did with boost.

By "turbo" I meant the whole turbo setup (specifically my poor fuel system and possible lean/detonating mixtures since I still haven't installed the new system yet). not specifically the turbo :-).

It doesn't miss and runs just as well as it ever did. It pulls just as hard too. No noises, doesn't burn any oil (from what I can tell), and easy to start and just runs the same. It just has that blow-by.

I keep forgetting that I haven't made a driving video. I'm sorry. I keep telling myself I'll make one with the new fuel system but I'll try and make one in a few days.

Something is wrong (broken,cracked) with the pistons/rings.

Most likely from detonation. Detonation you most likely could not hear.
That is why I recommend one of these.: http://www.jandssafeguard.com/

MBHD

I still think it has a broken ring.

Well just tonight, it had this random large stumble out of nowhere. It wasn't running lean, I wasn't even at half throttle (or trying to really accelerate). The whole engine shook and now it just absolutely CHUGS smoke out of the the PCV vent in the valve cover. Whatever it was, it did the engine in and finished off whatever cylinder(s) had bad rings.
Next up is to pull it out and rebuild it but this time I'll actually work on the rotating assembly. I'm going to re-ring it obviously and I'm going to try to find a way to get forged rods and pistons.
What I did last time was more of a turbo mock-up and a band-aid on the bad parts so I could run it for awhile (up until now). Now I'm going to try get everything how it should be as with proper machining on the engine and a strong rotating assembly. That will also give me time to get the fuel system set up and maybe get an intercooler in there too. But now the machine work and rotating assembly will hopefully be rock-solid so I can hook up the fuel system and throw 15psi at it.
I just need to have it all done by college (august/september) but preferably by summer.

Post some pics of the carnage when you get a chance.

I said it before, you are really ,really lucky that engine did not blow up a long time ago.

At least it lasted a little while to sort out some stuff.

Just remember, even if you get forged pistons in there, it will blow up also if you run the new engine the same way you had run your current engine. It will take some more abuse than cast pistons will.
2 cents thrown.

MBHD

Well here's some even worse news. I've was hanging out with some friends yesterday at a trampoline park and I managed to pull my left calf muscle lol. I can't walk so that makes it mighty hard to do every-day stuff much less work on my car :-/. I'm hoping it will be good enough to move around and work on the engine by spring break which starts next saturday but maybe that's wishful thinking.

I understand I need the fuel system set up correctly if I want to run it like I have been. But again, by the time I get everything back together, I hope to have the fuel system setup and install an intercooler. By running the "new engine", do you mean running the engine while it's new (not broken in) or something else?

I understand I rode it hard up until now and I'm surprised I didn't spin a bearing or throw a rod or something more serious. That rotating assembly is death-proof.

Once I can start walking around again, I'll try to make a video. All I can really show is the blow-by and maybe a short driving video.

I am meaning, when your new engine is all broken in, has enough miles to get on it,, new.

Unless you get a handle on your A/F ratios in a safe zone (you have not done that yet, I will add),still too lean
also you really need to know where your timing is are some of the ways your new engine is going to survive.

Sorry about your leg, your young & will heal fast.

MBHD

Well it turns out I shattered my fibula so haven't been able to do a whole bunch of heavy lifting or crawling under cars but I managed to get outside today and get the rebuild started.

Checked out the compression in each cylinder and it was pretty good in cylinder 1,2,4,5, and 6. anywhere from 120-150psi. Oh cylinder #3... 10psi of compression at max. Took the engine apart and the piston out... Not only did the piston ring come out in a few pieces but a nice big chunk of piston was missing on one side. Not to mention that the rod wrist pin was about 5x harder to move back and forth compared to the other good cylinders.

Here are pics of the day
















AND THE KICKER!!

Sorry to hear about your leg, how long is the cast going to be on for?

Thx for the pics!

At least now you know first hand what detonation can do to your engine.

While tuning my Syclone I see knock retard (detonation) a lot & I mean a lot! (I am still tuning & tweaking in other words, my tune is not perfect yet) But I cannot hear any knocking, it's not audible at all, but I know it is knocking & it's not a false knock.
I am tuning the A/F ratio in the 10.5-11.0 range while injecting methanol.

The thing that saves my engine from blowing up is the factory ECU pulls out timing & the J&S unit acts faster than the factory ECU which pulls out timing & therefore saves the engine & eliminates detonation.

As I always said before, you cannot always hear detonation either, you could say it is a silent killer of engines, hence the need for http://www.jandssafeguard.com/ ,sorry to sound like a broken record.

What is the new build going to consist of?
How does the cylinders look especially #3?


MBHD

Well the fibula is the bone behind your shin and doesn't support hardly any weight so the doc just told me to stay off it and let it grow back together. Doc said I'll probably be hobbling around for another 4-6 weeks but it's healing pretty fast so I'd say like 3 or so. At least it didn't need a cast or surgery. That would ruin all the summer swimming!

Well this time, I'm going to try to find a way to get everything correctly. The only bad part of that is it means that it'll cost a lot more. and the only bad part of THAT is that it'll take more time. I basically have 2 options right now.

-option 1 is to rebuild the engine very basically. Since all the cylinder walls looked fine (even #3) and had no grooves/scratches/etc., I could just replace piston #3, re-ring it, replace all the important bearings (mains, rods, and cam bearings, and an intercooler. and then if I have some extra money, use a turbo valvetrain and install lumps. This plan will probably have me driving sometime this summer
-option 2 is to rebuild the engine how I really wanted to all along but it would be on the scale of a few years since I'm going to be in college in 5 months and won't be at home to work on it or have the money to pay for it. That would consist of the boring it, forged pistons, re-ring, turned crank, 0 deck the block, align-hone (if needed), replace all important bearings, lump ports, turbo valvetrain, intercooler, and probably a J&S safeguard. Later down the road, I might even add in a alky injection system.

btw I also managed to break my harmonic balancer by using the wrong type of puller so I'm going to need a new one of those. I've seen ones by fluid-dampr? i think, anyone know prices or details about them?