It's ALIVE!!! (pics)

AngleT

AngleT

Always more tuning to do
It's ALIVE!!! (pics)(and now video)

An engine rebuild that ran over budget and out of time is finally running. I started this project 4 years ago and have been dragging this car and all its parts from house to house with the hope that someday I would get it running. Well that day finally came.

I solved A MAJOR issue yesterday that I didn't even know I had. I always found it "funny" that I would get little "sprits" of fuel coming up out of the dual Webbers. It was a problem that has been there since I put them on. It turns out that the exhaust system was too restrictive for the engine. I was running a PBS header with a 2" exhaust with high flow cat and Flowmaster muffler and 2 1/4" tail pipe. Well, yesterday when I finally got the engine to idle, things were just not right. The "sprits" of fuel had turned into more of a shower and it seemed that I had more pressure coming out of the carbs than the exhaust. The timing also had to be extremely advanced for it to run.

After brainstorming with my father about the issue, we came to realize that it wasn't cam timing that was my issue, but more than likely exhaust back pressure still in the combustion chamber when the intake valve opened causing an exhale/inhale effect through the carbs. Once I dropped the exhaust and only had the header on I gave it another try. The car fired right up...and up... and up. With the timing being so advanced and me using a remote starter switch, the panic of shutting the run away engine down could have won me some money on America's Funniest Home Videos.

It's diled in a little better now and sounds sweet, loud, but sweet. A few things to do before it's ready to drive around on the weekends.
1st new exhaust
2nd 4 wheel alignment
3rd E-brake cable

The rest is just detailing issues and not required for a sporting drive around town.

Here is a list of the goodies:

Bored and decked block
Shaved PBS big valve head with S2 cam and IAP racing valve springs
Adjustable cam pulley from Midwest X1/9
Cower rods
9.2:1 pistons from Bayless (the 11.5:1 pistons wouldn't fit after all that decking and shaving. Save for next car I guess)
Windage tray and increased oil pressure
Dual 40 DCNF Webbers
K&N air filters
MSD 7AL-2 ignition, Supercoil, and platium plugs
Aluminum flywheel from Apple motors
4 puck ceramic clutch and high tension pressure plate Clutchnet.com
4.54:1 finial drive and LSD from Colotti
Keizer 15" lightweight racing rims Yokohama 225/50-15 back 195/50-15 front
Drilled and slotted rotors
Braded brake lines and metalic brake pads
KYB struts in front Koni adjustable in back
IAP springs
IAP anti-sway bars front and back with polyurethane rubber
PBS exhaust header


Here are a few pics

DSCN3616.jpg

DSCN3612.jpg

DSCN3613.jpg

DSCN3617.jpg

DSCN3618.jpg


Video


:)
AngleT
 
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Perseverance has it's rewards

Sounds like it'll be a spirited motor. The engine bay looks meticulous as well. I'm just curious though as why you felt the need for 2 torque rods?
 
holy X!

Nicely done!

It looks great, and the specs are impressive, congrats.
What blue is that? It looks like "chiaro blu" ?

bravo!
 
2 torque rods

Only because there was room. I just thought it looked a little silly with the big mounts and a little rod. And it couldn't hurt to double up.

I can't wait to get it on a dyno to see what it will do.
 
Blue paint

It's a Lexus color. The metalic in it is blue, so its a blue paint with blue metalic flakes in it. Very nice looking in the sun. My brother calls it "Pepsi can blue"

Thanks
 
Congrats on getting it running! :)

But i don't think you have found the root cause of your problem.
I have almost the same motor and it runs great with the 2" exhaust on the PBS header. It runs great (and even better at lower revs) with the stock 1974 exhaust manifold and original muffler!

I would think either your cat is plugged or you have some other problem that is masked by removing the exhaust.
Have you driven it yet?
 
Short trip

down to the corner and back (1 block) just to say it truely moves under it's own power. The 11.5:1 pistons physically would not fit under the head, so I'm assuming that the compression is up there a bit. The 2" exhaust was NOT a manderal bend and choked at the corners. I put the dual carbs on and the new exhaust with header on at the same time and have always had the sprits of fuel coming back out the carbs. With the exhaust off and just the header on there is no sprits at all. I also have always had an idle issue too. Could never get it to idle slower than 1200rpm. With no exhaust I can get this engine to idle as slow at 500. (not good for it though)

I've got some exhaust parts I bought awhile ago that are manderal bent and 2 1/4. I'm going to build the exhaust with that first and then dial the engine in better. (without annoying the neighbors with the loud exhaust). It'll be a "seat of your pants" dial in until tax return time. There is a shop about a mile down the road with a chassis dyno. They said they could jet the carbs and everything on the dyno for no more than $1000, (but I still have to ask the Mrs.) Should be fun though.
 
I am with Ulix on this one. I have a few questions beyond Ulix's points:

1) Are you sure you cam is indexed properly?
2) What jetting and emulsion tubes do you have in the carbs - list all of them and verify each carb has the same jets etc?
3) What is you static timing set at?
4) Although it sounds good at the higher rpm it sure sounds to me that the carbs are out of sync; are you sure the two carbs butterflies are synced together?
5) Are you certain the float height is correct in both carbs?
6) What fuel pressure are you running?
7) have you checked the plugs at idle to see what they look like or done a plug chop evaluation?

Anyway there is my $0.02 but again I agree with Ulix that the car should run fine with the components you listed. My speculation is the carbs are rich at the lower end and out of sync. Good Luck.

Brian
 
Shadetree

Being honest, this is my first “hot rod”. My father and brother are Master Certified Diesel Mechanics and I’ve been raised around cars, but getting a car to run and building/tuning a High Performance engine/car are two different things and Diesel is not Gasoline. I have had almost every nut bolt and screw out and back in this X over the 16 years I’ve owned it, so I’m very familiar with the car. I will gladly take any advice from you X tuners that I can get that will set me on the path to getting the most out of this engine.

Thanks
 
Love to see what it could do

But I built it to be a "show with go" car and would need to shed a LOT of weight before I raced it seriously. (ie bumpers, stereo, seats, etc) It'll be mostly a street car for me.
 
Answers to questions

1) Are you sure you cam is indexed properly?
A: not really. I put a stock cam gear on it and lined up the timing marks for the cam. Then put the adjustable cam gear on it with the adjustments loose so when the crank was at TDC the slack could be taken out of the belt with the adjustable cam gear without moving the cam. It should be pretty close.
2) What jetting and emulsion tubes do you have in the carbs - list all of them and verify each carb has the same jets etc?
A: Will have to get back to you on that one. I can tell you that they are the jets that came with it from PBS.
3) What is you static timing set at?
A: Right now it’s at about 10 degrees BTDC, but that will change dramatically once I can drive it around. I'm only using a stock distributor with no vacuum advance.
4) Although it sounds good at the higher rpm it sure sounds to me that the carbs are out of sync; are you sure the two carbs butterflies are synced together?
A: I haven't done it this time yet, but I had them done a long time ago and haven't made any adjustments on the carbs. They were off the intake when I rebuilt the engine, so they should be close.
5) Are you certain the float height is correct in both carbs?
A: I believe so. That was one of the things I checked when I had trouble getting it started after the rebuild.
6) What fuel pressure are you running?
A: embarrassed to say that I'm only running a Purolator electrical pump with no regulator. I was going to "do it right" but the costs were a little much and this was the setup I had on it before I rebuilt the engine and it work fine then. It's on the "to do" list.
7) have you checked the plugs at idle to see what they look like or done a plug chop evaluation?
A: need more info on this one. Not sure what you are referring to.
 
Re; Love to see what it could do

Whay do you think you have to lose weight before you can race it? You must be thinking for drag racing. For Autox or road racing your car tuned the right way would be fast if driven right.
 
weight

I would rather do the auto cross than drag race. Even though it's got a little weight issue, it would still be fun to do. I've only been to one auto cross ever and that was as a spectator, not a driver. They have them around here pretty often, but going without my X even running kinda got me down. That should be changing real soon. :D
 
Try it (autox)

You will fall in love .Just do it once and you will be hooked. The more events you enter the better driver you will become and will begin to find loosing weight is not needed .I too once thought my car needed to loose weight the more events I go to the better and better I get. I’ve gotten to the point ware I don’t take out the spare tire 20# won’t make the difference but better driving will.
 
Tom,
cam timing is critical and very sensitive!
From your description, you really haven't set the cam timing at all, since with a heavily shaved head (such as the PBS BV head), the stock timing marks on the pulley are "wrong".
If nothing else, you could put the exhaust back on and vary the cam pulley setting in small (!) amounts and do some trial-and-error.

You may not need a new exhaust at all!
 
Hey Tom,

Thanks for the response, by the way that is a really nice car.

1) I would check the cam timing just to be sure and get the question off of the table. I set my cam by dial indicator on the tappet and a degree wheel on the crank. No timing marks used.

Try this link
http://xwebforums.com/forum/index.php?threads/630/

126_2632.jpg
126_2630.jpg



deckheadandcamrotation.jpg


2)OK

3) 8-10 degrees is good without the vacuum. That is where you want to be.

4) You really need to check this. It only takes a few thousands of a difference in the butterfly setting to affect the balance. I don't remember the best way to check a DCNF but I seem to remember using a drill bit. Set a drill bit (or rod) between the butterfly and the barrel and turn the idle screw until the drill bit can be slid out with a slight tug, now check the other carb and verify you have the same tension. DONT DROP THE BIT IN THE ENGINE - I believe I had a string taped to the bit just in case and make sure you measure the butterflies in the same spot, i.e. 6:00 in both carbs not like 6:30 and 4:00 - that is the hard part

5) If the float heights are not the same the fuel in the lower setting float has a higher climb up the emulsion tube and requires more air velocity to do it. The carbs can be in sync at idle and still be out in the mid range because the floats are out of whack. Check this one.

6) I don't know the rating on the Purolator pump but just check it is 3-5psi. 3-3.5 Would be ideal. I suspect it is fine. If you saw fuel coming out of the bowl vents I would be all over this one.

7) http://www.flixya.com/video/339745/The_mysterious_PLUG_CHOP_explained
This can be done at idle, 1000, 2000 - etc through each gear. For Idle run the car up to speed for a few minutes then bring it to an idle for a minute and shut it down then check the plugs. Make sure each cylinder looks the same and that they are tan.
http://www.sparkplugs.com/sparkplug411.asp?kw=Fouling&mfid=0
http://www.spark-plugs.co.uk/pages/technical/diagnosis.htm

One last thing, keep a log book on all of this. Start at ground zero and walk through everything again before you decide to tear apart the exhaust etc. Hopefully these points will lead to your root cause and hopefully this explanation will help to understand the basis for the questions.

Brian
 
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Congrats Tom... looking great... I've cetrtainly not heard of the...

... problem you describe before... but I guess you PROVED your case.

What might be "nice" now would be to run a straight MEGAPHONE pipe from the header flange straight back. Do this just five minutes BEFORE you move out...

HA!
 
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