LT1 and a T56 in a 55 Chevy

Thanks, Rick, that means a lot....
I started hot rodding in the 50's with a '54 Chevy, straight six and a powerglide,
drove it through high school and engineering school at UC Davis, sold it when
I moved to Maui to work for the sugar plantation here, should have kept it !
It was a "drop top", the girls all loved it in high school and collebe !!
Things all went "downhill" from there, but I really love working on these
machines, I think I love working on them more than driving them,
but it's a close call !!!
Willy
 
Swapped out the fixed pressure return line fuel pressure regulator for an adjustable one. I've used them on these motors in the past with good results.

55HTfuel115s_Jan2019.JPG


55HTfuel113s_Jan2019.JPG
 
yeah. a good quality and properly adjusted, adjustable fuel pressure regulator is generally going to potentially provide,
just enough more consistent fuel delivery volume to be worth a few extra hp, but its major benefit is in the fact in many cases,
it can easily result in 30- plus hp over a improperly functioning O.E.M, fp regulator. (not all that rare)
keep in mind theres a huge difference between replacing a fully functional O.E.M. fuel pressure regulator ,
with an aftermarket adjustable regulator ,
which may or may not provide any benefits and replacing,
a mal functional, O.E.M. fuel pressure regulator with an aftermarket adjustable regulator ,

https://www.thedailystar.net/shift/...ure-regulator-will-improve-performance-111412
http://www.ws6.com/mod-7.htm

Dyno Comparisons -- Adjustable Fuel Pressure Regulator Settings



afprgraf.gif


Here, the dyno shows a 16.6 horsepower and 14.6 ft/lbs torque difference between the stock fuel pressure (46psi) and 36psi with the LG Motorsports adjustable regulator. Actually, it was still making more power at 35psi than 36psi, but until I can measure my O2 sensors, I did not want to lean it out any further. The average gain here was 13.9 horsepower and 15.4 ft/lbs torque. Check out the Dynojet Race Routine between the stock and 36psi fuel pressure.

Something new: Dynojet is currently Beta testing their new WinPEP software for the dyno. With this software, they have the ability to graph up to 12 graphs at once. Check out the Dynojet WinPEP Graph of all the power between the stock and 35psi fuel pressures.

NOTE: One thing that I have found after some time with this mod is that the stock computer is quite smart. After lowering fuel pressure to achieve a better air/fuel ratio, the computer sees this at part throttle and adds injector pulsewidth to compensate. Basically, horsepower fell back off to where I started from. While normal trains of thought tell us that since O2 values are not measured during wide open throttle, that fuel pressure should have a long lasting effect here. Actually, it does not. The computer uses the last known long term fuel trim integer at WOT, which is to add fuel since at part throttle it has adjusted for being too lean.
related threads

http://garage.grumpysperformance.co...ss-fuel-pressure-regulators.12776/#post-65998

http://garage.grumpysperformance.com/index.php?threads/fuel-pressure-regulators.635/

http://garage.grumpysperformance.co...eplacing-a-c-4-fuel-pump.33/page-2#post-75720

http://garage.grumpysperformance.com/index.php?threads/c4-corvettes-fuel-system-info.67/#post-37351

http://garage.grumpysperformance.co...-big-a-fuel-pump-do-you-need.1939/#post-35934

http://garage.grumpysperformance.com/index.php?threads/fuel-pressure-drop.10624/#post-45703

http://garage.grumpysperformance.co...l-line-sizing-return-vs-feed.3067/#post-44732

http://garage.grumpysperformance.co...ed-flow-and-its-limitations.11100/#post-49467
 
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Great Comments, I love it!!
Particularly with a heavily modified motor, some definite tuning involving the fuel supply/pressure will be necessary.

Got the MAP sensor (Manifold Absolute Pressure)
installed with four O-rings on the sensor probe,
that should seal it just fine....
55HTelec021s_Jan2019.JPG


Put in the check valve for the crankcase ventiliation system
with it's special rubber grommet, and the vacuum connection
for that....
55HTelec022s_Jan2019.JPG


And stuck the hose on it....
55HTelec023s_Jan2019.JPG


The only place on the block I can find for the
knock sensor was here down below the 5th
and 7th cylinders, I hope it's right....
55HTelec024s_Jan2019.JPG


I had to run a pipe thread tap in as the threads in the block
were pretty rusty, the sensor screwed in ok....
But it was a tight fit....
55HTelec025s_Jan2019.JPG

55HTproject12
 
Update on my list of sensors needed for this
'93 LT1 speed-density efi system:

1. MAT
Manifold Air Temperature
This fits in the air ducting in front of the throttle body,
I found one, need to figure out where to put it.

2. ECT
Engine Coolant Temperature
I found one, now I need to figure
out where it goes....

3. IAC
Idle Air Control
This goes on the bottom of
of the throttle body, I found one,
it is installed.

4. TPS
Throttle Position Sensor
This goes on the throttle body,
on the end of the shaft,
I found one, it is installed.

5. MAP
Manifold Absolute Pressure
Bought a new one from Napa,
it needs a special seal that did not come with it,
but I found four o-rings that fit nicely,
it is installed

6. Knock Sensor
I found one
and mounted it in a threaded hole in the block,
down next to cylinders 5 and 7.

7. O2 (Oxygen) Sensor
I have one, need to weld a bung
on one of the header collectors for it.
 
Got the ECT (engine coolant temp) sensor installed in a port
on the left side head between cylinders 1 and 3.
55HTelec026s_Jan2019.JPG


Then started working on hanging the new firewall pad on the inside under the dash...
 
perhaps its just the photo angle perspective,
but that left end, spark plug ignition wire clearance , in the photo, looks absurdly restrictive
 
Yes, it's just the perspective, plus those are just old junk sparkplugs I just loosely screwed in to keep the ports plugged...
Another view after tightening them in all the way finger tight only...
55HTelec029s_Jan2019.JPG


I found out that this sensor is supposed to mount in the water pump, so I moved it...
55HTelec027s_Jan2019.JPG


55HTelec028s_Jan2019.JPG


Now I have to find the right sensor for the dash temp gage, which goes in the head...

Ran the battery cables up to the firewall from the battery,
along the right side of the floor...
55HTelec030s_Jan2019.JPG


Now I have to decide if I want to put the cables through the firewall
here on the right side...
where I will have to run them across in front of the firewall to the starter and block....
55HTelec031s_Jan2019.JPG


Or run them across the front of the floor on the inside to the hump,
which put them very close to the starter and block on the other side....
55HTelec032s_Jan2019.JPG


Hmmmmmm.....
 
That's a great idea, I'm going to check that out...

Meanwhile, went hunting for a temp sensor for the dash gage...
55HTelec034s_Jan2019.JPG


Found one at my local Napa store...
55HTelec035s_Jan2019.JPG


I haven't done anything about what dash gages I want to run,
still looking around, maybe go all digital ??


Meanwhile, I learned that the knock sensor would perform better
down here at this location on the right side of the motor near the
oil pan, in front of the starter, so moved it here...
55HTelec036s_Jan2019.JPG
 
Nice Willy !

ACCEL makes shorty street and Race spark plugs for the Corvette, SS Impala, and Z28 Camaro L98 & LT1 engines cylinder heads.
 
My T56 tranny clutch uses an exterior slave cylinder, and I need to find an appropriate mc and figure out the clutch pedal linkage to function properly. The aftermarket mc's I looked at are mounted on the right side of the brake mc and pedal, using the cross shaft setup of the stock '55 under the dash, and where they go through the firewall, they are perfectly positioned to hit my header tubes !!! I'll post some pix when I get some. My current thinking is to find an appropriate sized mc that I can mount on the firewall on the left side of the brake mc, and fab the appropriate linkage under the dash from the pedal that is on the left of the brake pedal, through the firewall to activate it. Shouldn't be hard to do, but I need to figure out what size mc bore to use, and how much leverage I need at the pedal to actuate it correctly. Part of that is the bore of the slave cylinder, and how much movement it needs to actuate the clutch properly. All data I do not currently have.

Another big "Hmmmmm" to solve....
-Willy-
 
All right, lemme see if I can get this posted
in one piece after way too many beers...

My T56 has a hydraulic slave cylinder on it,
so I need to come up with a hydraulic master cylinder
to operate it...

The aftermarket ones I've looked at for the 55 Chevy
comes through the firewall down low where the mechanical
linkage used to come through, but the headers I'm using
interfere with that location, so I'm looking at alternatives...

Look at that hole down on the car's right of the steering column,
that's where the original mechanical linkage came through, I
used that hole when I built "Patches", my 55 blown rat rod gasser...

Unfortunately it's way too close to the header pipe
for the heavily angled hydraulic system I've seen that is
designed to come down through that hole, so I'm
going to design my own system...
55HTclutch01s_Jan2019.JPG


I have this master cylinder on the shelf that has a 7/8" bore and
a max stroke of 1-5/8", so I have to engineer a system for that...
55HTclutch02s_Jan2019.JPG


This is the slave cylinder that came out of my wrecked '93 Camaro
on the T56 tranny, it is a 1" bore and 1-5/8" max stroke...
55HTclutch04s_Jan2019.JPG


Here's the original clutch pedal, held in front of the firewall....
as you can see it crosses over through the brake pedal pivot,
and the original linkage came down through that hole that
is now too close to the headers for a hydraulic setup....
55HTclutch03s_Jan2019.JPG


So I'm going to engineer adding a lever on the left side of that setup
to actuate that master cylinder, I need to find out the stroke required
for the clutch, then I can locate the master cylinder and how much
pedal movement and master cylinder stroke by locating the MC
at the proper location. The square of the diameters of the cylinders
represents the volume of fluid moved, that gives me a ratio of
0.77 to 1.00 with the mc at 0.875" and the slave at 1.00"

What fun !!!
 
Here's a sketch of what I'm thinking...
design for a 1" movement at the slave
to operate the clutch, I hope that will be enough....

Extend the clutch pedal shaft on the left
and add a lever to give 2.7" effective swing
to activate the master cylinder with 1.3" movement...
The pedal has 5.5" of swing available at the floor
and is 11.5" long, the ratios are shown below....

55HTclutch05s_Jan2019.JPG


I hope this made sense....
 
Is that a 58mm throttle body? The opening in LT1 intakes is 52...the 58's require porting to not create a turbulent step just inside the throttle body. Common thing to deal with in the TPI/LT1 world.
 
Yes, I had to machine the plenum openings to match the 58's, and as the heads were also ported I matched the plenum outlets to those intake ports, should be good to go. When I open the throttle blades it looks good, a clean entry....

Thanks for noticing that....

Ordered this setup from Dakota Digital....
It's quite a nice looking digital setup with analog display,
Another challenge to get it working the way I want....

dak-vhx55ckw_sn_xl_s.jpg


It's listed as a VHX 55 CKW
 
Here's a sketch of what I'm thinking...
design for a 1" movement at the slave
to operate the clutch, I hope that will be enough....

Extend the clutch pedal shaft on the left
and add a lever to give 2.7" effective swing
to activate the master cylinder with 1.3" movement...
The pedal has 5.5" of swing available at the floor
and is 11.5" long, the ratios are shown below....

55HTclutch05s_Jan2019.JPG


I hope this made sense....
A Real Retired Engineer Engineering !
 
Last one of those I did, i took a junk power booster and cut off the bracket...used GM pedals on the other side...and bolted a hydraboost to it. It ended up all working together flawlessly, using all GM parts. No fuss, no muss.
 
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