Inliners International Forums General Discussion Hi Performance Nova project progress

Yes, but now the weld color will match the tube color.

Absolutely nothing to do with performance. I just wanted to finish the job and make it look nice. Very minimal leakage on the two bolt flanges. I did grind a bit based on the carbon witness marks and added a small bead next to the bolt holes to seal them up even better.

Yes, I did blend in a radius to all three ports. It's not a lot since the top of the manifold casting is only about 5/16 inch thick.

I noticed one pushrod wasn't spinning based on witness marks from the guide. That raises the question of whether a lifter also isn't spinning so I checked all the lobe lifts. All were .266-.268 versus .2706 on the cam card. I think and hope all is OK with the cam. This is the fourth engine I've had this cam in and at least the second set of lifters so it doesn't owe me anything.



And the throttle bracket:

Got any tracks near you so you can run some 13's? Just need sticky tires.
Should be able to run some desent times, you got the torque!

Looks good.Nice job on the headers.

What RPM does it make power to?

Any cold air going to the carb?

MBHD

Cordova IL track is close. 13's? That seems optimistic but maybe. Will for sure need sticky tires instead of my street radials. And perhaps a better driver?

Thanks. I figured with as much work as I put into those headers I should finish the job and make them look nice. I think the welds will disappear when colored by exhaust heat. Plus I needed the O2 sensor bung. Don't know if I really needed two of them but it might come in handy some day. I did buy a wideband sensor so I'm anxious to see what it says.

I've run it up to 5500 rpm or so repeatedly. It's still pulling that's just where I chicken out. Now that I have a good set of valvesprings and have verified no piston/head contact I'll wind it up higher to see what happens.

No cold air yet but that's a possibility. What do you think about a rev limiter? Then I could keep my right foot planted while I run thru the gears. I hesitate to do that now because my shifter is a little sloppy. It's an old Hurst Competition Plus on top of the Muncie M20 wide ratio. Tranny is well used but in good shape. I did sleeve the countershaft pin (it's the larger 1" pin), square up the case (corrected warp from welding on the ears), and replaced a few parts inside.

Hey strokersix
If you every want to put in a 60s style hurst inline shifter i may have a extra one or two.I might part with.

PM sent to Larry.

I would,, Maybe a MSD 6AL box?
They seem to hit soft & not make any sharp or abrupt change when it hits the rev limiter.

I ran one in my Camaro when it was Paxton supercharged, very mild hitting.

I remember when I put in a 6000 RPM limit chip in the box, my Autometer tach needle would read about 5500 RPM & the engine was missing, I did not think it was actually hitting the rev limiter, engine reved quicker than the needle could move.

My friend told me to put the 7000 RPM chip in the MSD box & bam, that was it no miss,, damm engine reved too quick LOL.

BTW, what M20 do you have, close or wide ratio?

As far as running good ET's, IIRC, my best ET @ a 3000+ elevation track was when I ran a wide ratio M21 4 spd a very, very mild 250 .030 over, approx 10:1 compression,4 bbl intake & a small 500 CFM AFB. 4:10 gears
I ran a 14.3 which I thought was slow @ the time, I was always comparring to the V-8's, come to find out here, it would have been a record that would still be standing here today in the International inliners record books, I still thinks that funny.

I have run many different combos, memory fads a bit but I found the timeslip w/what combo & had @ the time I ran.

I had the original 3spd, horrible 2nd to 3rd gear RPM drop,4spd Muncie,5 spd T50 & a TH350, next a 4L85E

MBHD

My Muncie is a wide ratio. It's a compilation of Muncie parts of unknown history, 10 spline input, 28? spline output, 1" countershaft pin. Rear gears are 3.08 8.5 inch with factory posi. I had 3.42 gears in the car at one point but I didn't like the freeway rpms so went back to 3.08.

Limited mechanical advance by adding weld to the weight tips.





The added 1/2 inch riser under the carb required air cleaner modification for hood clearance and now has a big block engine decal. Also note the header tubes and welds are turning color already. Hooked up my old Edelbrock O2 sensor (not wideband) and indicates the carb might be a bit rich but not excessive.



Now the bad news. Something broke in the valvetrain. Not sure what. It sounds like a 250 in an old pickup truck, no offense to truck owners here, just a reference to the typical well used 250 ticking valvetrain. My first guess is a cam lobe went flat but we'll see. Maybe I should drive a little slower.... NOT!

Is the weld limiting the mechanical advance?

I just weld up one of the slots under the advance weights.


MBHD

Yes, the weld limits mechanical advance. In the second photo you can see the tip of the weight contacts the cam close to the center axis. The weight can't get enough leverage to continue advancing the timing. The vise keeps the weight cool so it doesn't soften or damage the bushing while welding. The tip is soft and will eventually wear away but this car won't see enough hours for that to be a problem.

As I'm sure you have observed, I don't always do things the same way others do.

Good news! Pulled the valve cover tonite and it was immediately obvious that #5 intake rocker was loose. Pulled all 12 rockers off. I checked all the cam lobe lifts (Comp 252) and all good. All 12 pushrods are now spinning. Torqued the head bolts to 95 lb-ft, some were at about 85, some didn't move. Then reset all 12 rockers to 1/2 turn preload and cinched the locking setscrews tighter this time. Manifold fasteners all tight. The loose rocker doesn't roll as silky-smooth as the other 11 but I think it's OK.

That is good news! Had me worried. Glad it was something simple. Did you take it back out for a spin?

Nope, not yet. Maybe tomorrow.

While your taking it for a spin, go to Cordova IL track & see what it can do,,, if you want to.



MBHD

It's back! Runs good. I have some work to do on the ignition. Mechanical advance curve still needs improvement and I'm going to look into a rev limiter. Anyone used and recommend the HEI style that swaps in place of a stock module?

Great!!, how much initial timing do you have?

MBHD

Eeewww . Maybe the needle bearings are going away. Or the pushrod tip galled up the cup in the end of the rocker. Been there. I would recheck the rocker arm for damage sometime soon. If those little needles get loose and scurry throughout the lubrication system It won't be pretty.

Yes, I'll keep an eye (ear?) on that rocker.

Tom checked my advance curves when I visited (thanks Tom!) for a baseline. I added the weld on the weights to cut off the top end of the curve. Didn't get a chance to work with it yet so I don't know for sure what the curve is now. I intentionally made the welds bigger than needed and I'll trim them to get the curve I want. I set initial at about 12 degrees. I'm getting some spark knock just off idle so perhaps 8-10 degrees initial would be better. 87 octane no ethanol. It's a work in progress.

Interested in total mechanical (initial plus centrifugal) timing suggestions. 250/292 engine, 9.4 static compression, Comp 252 cam (206@.050 I think), naturally aspirated. 32 degrees about right?

I believe Tlowe has said the best timing is @ 32 degrees, did he not tell you? Dyno proven results w/a 250 & 292.

I would suggest to put the car on a dyno & see what your engine likes. 2 cents thrown

Hows your A/F ratios?
MBHD

Yes, he told me that.

I think A/F ratio is pretty close by how it runs, possibly a bit rich based on the narrow band O2 sensor output.

No dyno until I'm happy with the tune. There is clearly work to be done.

I thought you have a wide band?

Works much much better more accurate & fast acting. That will speed up your tuning greatly.

MBHD

The dyno motors were tested at higher total timing (34-36). We were running much higher octane though (110 sunaco).

32 degrees ain't bad and much safer with low octane fuel. The bathtub chambers do like plenty of timing.
8-10 initial will help back the total down also.

You need to get that WBO2 hooked up. Do not expect the engine to like running at stoich (14.7 to 1). Mine likes 12.75-13 at idle. The guage will be more of a reference. It is effected by plenty of variables. Cam, timing and exhaust leaks will make it read funny. I was told long ago to use it as a reference to find where the engine likes to run at. This A/F varies at different rpms and loads.

Does the engine run any differnt with the last head/ valve setup?

Runs about as strong as before. Which is good because I hope it runs even better when I get the ignition sorted out. I plan to work on it today.

O2 sensor shows rich but not terribly so. Usually it tapers off to lean while cruising and it's not doing that. I agree, I need to install the WB sensor.

Try to get some more vids.

How about that shifter? It will take longer to install that. But it will put a big grin on your face.

I'll have to pull the seats, console, and carpet, then do some floor modification to get the shifter installed. Need to work up motivation for that. Seats out will be a good time to install the WB gage.

Nobody here has run the HEI module rev limiter??????

http://www.northernautoparts.com/ProductModelDetail.cfm?ProductModelId=15650

I would just get one of these. MSD made them smaller than before.
http://www.amazon.com/MSD-Ignition-6425-...13859749&sr=8-3

These work great also.
http://www.msdignition.com/Products/RPM/...ng_Control.aspx


You can advance your timing when trying to get max MPG.
Great for when you run nitrous & you would need to retard your base timing.
It worked great for me.

MBHD

Ok here is where I ended up: Centrifugal advance starts at about 800rpm goes up to 15 degrees at 3000, topping out at 18 degrees. Initial 12 degrees for a total of 30 degrees mechanical advance. Vacuum advance starts at 5 inches up to 18 degrees at 13 inches. Idle speed 700rpm.

Runs good. It only rattles if I intentionally lug it down hard, not a normal operating condition. Rich/lean indicator flickers lean when cruising 40-60mph, holds steady rich cruising at 70.

Centrifugal could probably come on a bit stronger, full in at 2500 perhaps. A/F ratio could lean a bit at high speed cruise but I'm not in a hurry to fiddle with that because it's pretty close now.

I am ready for a bigger camshaft. This one (Comp252 )starts to give up over 5000rpm. I think I would like to get up to 5500-5800rpm.

Hank, The advance control knob in the cabin sounds cool. My HEI works fine, what benefit other than the remote timing control will the red boxes give over my HEI? Multiple sparks for more complete combustion? Big red boxes don't fit well with my sleeper look but if there is a performance advantage I might consider it.

You will get a hotter spark,more complete combustion.

If you ever seen first hand between a stock HEI spark @ the plug & compare it to the multiple sparks of the MSD unit,I think you will most likely buy one from that comparision alone.

You could make more power & better mileage w/an MSD unit installed.

I know of guys running there stock HEI units on there Syclones & Typhoons that when they run a methanol injection system, it is causing there spark to blow out, then to reduce the tendacy of the spark blowing out they will close there gap down to as much as .022".

I to, use the stock HEI unit on my Syclone & run methanol injection, but I just added a MSD6 box, I never have to close up my spark plug gap & I run 24 psi of boost pressure & spraying a lot of methanol.

Features
•With Soft Touch Rev Control
• Higher output with 530 primary volts and 135mJ of spark energy
•Efficient components use less current to produce more power
•Set an rpm limit on the 6AL with two rotary dials
•Same bolt pattern as the original 6AL with a lower profile housing
•Built-in LED for system checks

I would not say you are pretty close w/your ideal A/F ratios until you install a wide band set-up. You will be in for a surprise.

Narrow bands are really an inferior product as compared to the wide band.

MBHD

That's OK. I think I'm better able to judge this than you anyway because I am here with hardware I am familiar with and you are not. I may be surprised, maybe not, we'll see. Either way I'll post here what I find.

BTW, my 2-bolt flanges are not leaking.

I am not saying you cannot tune w/a narrow band, it's possible & has been done for many many years.

It's just the narrow band is so slow in response time your A/F ratios could be way off @ especially during gear shift points.

I did tune my Syclone w/a narrow band O2 & w/that (narrow O2 sensor) I had the worlds fastest stock turboed Syclone, for about 8 years. I had no extra cash to get a wideband.

I did have a reading problem during the shift points though, the narrow band would show full rich @ the top of each gear change (thinking it was fine) but actually was dangerously lean,there was a couple second delay with the readings w/the narrow band O2.

I now use an old Innovate LM1 unit on the Syclone.
It was not until I wanted to turn up the boost & lean on it a bit more, (lean it out)I would only feel comfortable doing this with a wideband. I could have done it w/a narrow band,just much safer w/a wideband IMO.

Guys still tune there Buick GNs & Regal T-Types w/there stock narrow band, getting advise that has been passed down from older owners, there were so many of those cars made it's pretty easy to get good info on what works & what does not work & what's lean & what is rich, all measured in millivolts w/there scan tools.
One of the main reasons I tell guys to get a wide band O2 is to speed up the tuning process, most times you do not need to take out your plugs to look @ them.

It would be absolutely essential to get a wideband when you are forced induction, being too lean will destroy an engine very quickly & a wideband takes away the guessing, you know exactly when it's too lean or too rich right there & right now.

When I had the Paxton superchager on my inline 6 I did it the old fashion way, I jetted it richer right off the bat as compared to my normally aspirated set-up. Took plug readings (a lot) It was a somewhat long process tuning 3 DCOE's, but hey I learned.

MBHD

Any updates?
I love this thread!

X2
I'd like to hear about it also.


MBHD

I cleaned and painted my power steering pump and removed a couple extra fittings from the high pressure side.

Headers are a nice pretty color now. I'm very pleased with how they turned out.

I did get the car out for a blast this weekend. It really runs well. Not sure what to change next. Inline shifter and wideband O2 sensor are possibilities. What I'd really like to do is tear it down, reweld the subframe, and install subframe connectors. Maybe some lighter weight front suspension would be cool too. Got my eye on those Detroit speed hydroformed subframes but that would eat up several years worth of car project budget.