GTO resto mod update

[Aerovette]

Scott, I have loved that GTO since the first picture you posted and it just keeps getting better !

[GTOguy]

Originally Posted by mrvette

Has to have a rag top before I would have to steal it.......

I've got you covered. Only mine has about 400 HP less at the rear wheels than the OP's hardtop. Can't have everything!

[mrvette]

Originally Posted by GTOguy

I've got you covered. Only mine has about 400 HP less at the rear wheels than the OP's hardtop. Can't have everything!Attachment 77103

Yeh, but it's a cool breeze at 90f outside,

[Jeff78]

Here's my old girl.

[mrvette]

Originally Posted by Jeff78

Here's my old girl.

THE GAL in your avatar looks better........

[simpleman68]

Originally Posted by Egnalf

damn nice project. any chance its overfeeding fuel at the lower end?

According to the tuner, the curves are spot on and a bit lean below 3k if anything.
Scott

[simpleman68]

Originally Posted by Jeff78

Here's my old girl.

Very nice!
Scott

[GTOguy]

That's a beautiful '64 Jeff78! It's amazing how good they look with the right wheels (not 20") and original steering wheel, etc. That car is badass all the way.

[Grey Ghost]

Originally Posted by simpleman68

According to the tuner, the curves are spot on and a bit lean below 3k if anything.
Scott

Not trying to second guess or play arm chair mechanic. I understand he has experience, knowledge, etc...

If it's lean or a bit lean I would VERIFY with the mfg. that the fuel pump is capable of pumping enough fuel to prevent it going into a lean condition. Lean can melt pistons and rings....I would err on the side of rich vs lean.

[GTOguy]

Originally Posted by Grey Ghost

Not trying to second guess or play arm chair mechanic. I understand he has experience, knowledge, etc...

If it's lean or a bit lean I would VERIFY with the mfg. that the fuel pump is capable of pumping enough fuel to prevent it going into a lean condition. Lean can melt pistons and rings....I would err on the side of rich vs lean.

I agree, with a caveat: if he's lean below 3,000 rpm, he won't hurt anything but his drivability with stumble and hesitation and running a bit hot, possibly. UNLESS he's in a 4x4 and at high load at low rpm, like rock crawling or if he's pulling a boat or a trailer. Then, look out. But yeah, too rich is always better than too lean, just like too loose is better than too tight with valves. And so on....

[simpleman68]

Originally Posted by Grey Ghost

Not trying to second guess or play arm chair mechanic. I understand he has experience, knowledge, etc...

If it's lean or a bit lean I would VERIFY with the mfg. that the fuel pump is capable of pumping enough fuel to prevent it going into a lean condition. Lean can melt pistons and rings....I would err on the side of rich vs lean.

Always happy to hear input and I enjoy troubleshooting problems like this.

The tuner set it up to run leaner at that range and I forget why. At any rate, the pump is making enough pressure to provide adequate fuel at WOT (7200 rpm)
I don't think this is a pump issue though I know guys that have run boost-a-pumps but they are usually making 1000+ hp and running FI above 15 psi.
Scott

[simpleman68]

Originally Posted by GTOguy

That's a beautiful '64 Jeff78! It's amazing how good they look with the right wheels (not 20") and original steering wheel, etc. That car is badass all the way.

Agreed, I really don't care for the super low profile ghetto wheels that I see on some of these.
It's a fine line because the stock wheels make it look a bit like a toy with fat/sloppy sidewalls.

I went with 18" all the way around and still have good sidewall section in a rim that echoed the old torq thrust wheels.
Scott

I have the original Rally wheels in their boxes but the orig owner put these on instead.



With the the 18s

[simpleman68]

Originally Posted by Mike Mercury

[Grey Ghost]

Originally Posted by simpleman68

Always happy to hear input and I enjoy troubleshooting problems like this.

The tuner set it up to run leaner at that range and I forget why. At any rate, the pump is making enough pressure to provide adequate fuel at WOT (7200 rpm)
I don't think this is a pump issue though I know guys that have run boost-a-pumps but they are usually making 1000+ hp and running FI above 15 psi.
Scott

I'm sure they have hooked up a scan tool to watch the individual injector data? Volt, ohm, graphing it while running, etc...?

Do you have an economy tune and a beast mode tune? Or other tunes saved? And does it do the same thing in all of them?

[simpleman68]

Originally Posted by Grey Ghost

I'm sure they have hooked up a scan tool to watch the individual injector data? Volt, ohm, graphing it while running, etc...?

Do you have an economy tune and a beast mode tune? Or other tunes saved? And does it do the same thing in all of them?

I have a fixed tune that is an aggressive street tune.
It's got gobs of power but that damn stumble around the 3500 rpm range (only under WOT) is maddening.

As soon as it revs above to 4k + it pulls all the way to redline.
Scott

[Grey Ghost]

Originally Posted by simpleman68

I have a fixed tune that is an aggressive street tune.
It's got gobs of power but that damn stumble around the 3500 rpm range (only under WOT) is maddening.

As soon as it revs above to 4k + it pulls all the way to redline.
Scott

I would want a few tunes to play around with. Economy, if you were ever to drive it on a tour, etc...beast mode for track...etc...

I think someone needs to plug a scan tool into it and go to live data and a test drive. Watching the fuel pressure, injectors, timing, etc...with live data and driving it.

[simpleman68]

Originally Posted by Grey Ghost

I would want a few tunes to play around with. Economy, if you were ever to drive it on a tour, etc...beast mode for track...etc...

I think someone needs to plug a scan tool into it and go to live data and a test drive. Watching the fuel pressure, injectors, timing, etc...with live data and driving it.

Would be interesting to be able to flash it on the fly like the Livernois Motorsports tuner I had for my F150 ecoboost.

He did tune it to be fairly conservative at lower RPMs and at higher revs, it really dumps fuel as needed.

I can get 22 with it on the highway if I keep it under 75. Not too damn bad for a non-aero, 3400 lb brick.
Scott

[GTOguy]

Originally Posted by simpleman68

Agreed, I really don't care for the super low profile ghetto wheels that I see on some of these.
It's a fine line because the stock wheels make it look a bit like a toy with fat/sloppy sidewalls.

I went with 18" all the way around and still have good sidewall section in a rim that echoed the old torq thrust wheels.
Scott

I have the original Rally wheels in their boxes but the orig owner put these on instead.



With the the 18s

IMO, put the Cragars back on . Much better look for the car.
Seriously, as for slightly lean at cruise/low rpm, the tuner likely has it set for maximum economy, which you are experiencing at 22 mpg. If you tip into the throttle at cruise, it will go rich as intended and off you will go. My '67 gets almost as good economy, but with a stock-de-tuned original engine, running the original distributor and points distributor. My secret is a 2.56 posi I installed out back. I get 21 mpg at a solid 75-80 mph and it cruises 91mph at 3000 rpm. It gets better MPG than my Tundra pickup!

[69camfrk]

Love it!!

[simpleman68]

Originally Posted by GTOguy

Seriously, as for slightly lean at cruise/low rpm, the tuner likely has it set for maximum economy, which you are experiencing at 22 mpg. If you tip into the throttle at cruise, it will go rich as intended and off you will go. My '67 gets almost as good economy, but with a stock-de-tuned original engine, running the original distributor and points distributor. My secret is a 2.56 posi I installed out back. I get 21 mpg at a solid 75-80 mph and it cruises 91mph at 3000 rpm. It gets better MPG than my Tundra pickup!

We spent a lot of time discussing the build and tune before any parts were ordered.
I've spent 35+ years turning wrenches and building street/strip cars. I sold the last race purposed toy and wanted a nice street cruiser with some extra punch when desired.

Ports are 285 cc (11.5:1 comp)
Cam: 248/260 .65/.655 111 LSA

This is why I figured I was getting cam surge initially but after a retune it was still there.

Any mileage I get is coming from the 6 speed trans (T56 super mag) final drive is .63
At 80 I'm ~2400 rpm
Scott