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Resident Ford Nut
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Discussion Starter #1 (Edited)
Pulled the 342" ( 4.00 x 3.40) out of the Mustang Bonneville car and put it on the dyno. Dad had the build sheet from the guy who owned the car and it seemed like a stought little engine:



The engine needs a little re-fresh as it over-heated 3 times at Bonneville and has a small water leak at a head gasket. We decided to run it to see what it makes for power. On the salt it would only pull 6,300 in 3rd which I thought was 400-500 below peak power.
1988 Mustang Gt went 179.79 on the 5 mile course with this engine ........ 6,300 rpm and 62 psi oil pressure.

Engine specs:

342" ( 4.00" x 3.40")

AFR 205 heads, ported ( no flow numbers...sorry)

12.5:1 Probe pistons, Akerly and Childs rings

Holley HP 750 carb

Edelbrock Vic jr intake ported.

Cam.. solid roller: dur at .050 254/266, .637/.657 lift, 110 lobe sep.

So what's your best guess on power?

Made a couple of pulls then pulled the Holley hP 750 and replaced it will my C&J Engineering modified Demo 750 with a Holley 850 base plate to see what it would do.

Made a total of 7 pulls and was done.... 4 pulls with the Holley and 3 with the demo with a re-jetting.

Best guess ? HP and trq w/ RPM

I'll post dyno results tommorrow night.

S CP
 

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Resident Ford Nut
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Discussion Starter #3
See edit


S CP
 

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Discussion Starter #6

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Discussion Starter #8 (Edited)
My guess going into this was 525 @ 6,800, 425 lbs ft @ 5,800:

Yesterdays results with the HP 750 with dyno headers 1 3/4":

495Hp at 7,000, 407 lbs ft at 5,900


With modified Demo 750 with an 850 Holley base: C&J Engineering
from 2004

507 hp @ 7,000, 413 lbs ft @ 5,400

Today: With Kooks stepped/merge collector headers 1 3/4 - 1 7/8" Fox body headers

520 hp @ 7,000, 420 lbs ft @ 5,400

engine was making 517 @ 7,200 where we stopped

We made two pulls and were done.. second pull made peak of 518 at 7,000 - 7,200

We did a leak-down after the warm-up

5 cylinders leaking 3%, 2 were leaking 4% and 1 was 5%.

The guy who built the engine in 2005 advertised it as a 500hp 342 long block. This is a happy little engine.

Heads will come off and we will check the bearings and it's ready to run another year.

S CP :happy:

Jon
 

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Resident Ford Nut
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Discussion Starter #9

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Resident Ford Nut
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Discussion Starter #13
I thought in the original post Sleeper said it had 12.5 Probe pistons.

I think he's suggesting it's not 12.5:1 as advertised.

I think it is.

S CP :D
 

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Discussion Starter #14
The basics from a couple of pulls:




S CP :D
 

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Congrats John thats stout for 342" and 179mph is rolling hard:))THumbsUp
who ported the Eddy Vic Jr?that my next project..
Some old schoolers might say 205cc head is to big for 342",but if valve timing events are correct IMO it can have very good street manners
I luv my budget SBF 4.030 b 3.4" stroke
1969 junkyard seasoned 302 Mex block
OOTB canfield 195cc
OOTB Vic jr
flat tops netting 10.75 to 1 CR
custom ground hyd roller .600/.580 230/[email protected] 112.9 LS (idles at 750 RPMs @ 14inch Vac)
Prosystems low budjet 750CFM
1-3/4" Accufab longtubes
1965 Shelby GT350 clone 3250Lbs with fat driver could be everyday driver setup with stiff susp for cornering ran [email protected] with only 2600 RPM stall and tall rear ratio at 3.25 with puny 225/50-16 DRs on all four corners (full Exh exiting at rear bumper)
 

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Resident Ford Nut
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Discussion Starter #16
It's a good running little engine, very happy with it. When the heads come off they go to my guy with the intake manifold for a little work.

I'm thinking it's close to the limit of a stock block.

S CP
 

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It's a good running little engine, very happy with it. When the heads come off they go to my guy with the intake manifold for a little work.

I'm thinking it's close to the limit of a stock block.

S CP
is it just a late model 5.0 block?they are very limited.machine work has to be spot on and tuneups need to stay conservative at 500HP or that block won't last:no:
I was very lucky to find a standard boreMexblock that has the thicker 1" mains and it sonic tested good.we had the freeze plug bores tapped for screw in type like boss302s
I hav punished it on road coarse turning 6600 max for years now without any issues

who do you use for porting heads and intake as i would like to do mine soon as there is defiantly some power to be had?
 

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Congrats John thats stout for 342" and 179mph is rolling hard:))THumbsUp
who ported the Eddy Vic Jr?that my next project..
Some old schoolers might say 205cc head is to big for 342",but if valve timing events are correct IMO it can have very good street manners
I luv my budget SBF 4.030 b 3.4" stroke
1969 junkyard seasoned 302 Mex block
OOTB canfield 195cc
OOTB Vic jr
flat tops netting 10.75 to 1 CR
custom ground hyd roller .600/.580 230/[email protected] 112.9 LS (idles at 750 RPMs @ 14inch Vac)
Prosystems low budjet 750CFM
1-3/4" Accufab longtubes
1965 Shelby GT350 clone 3250Lbs with fat driver could be everyday driver setup with stiff susp for cornering ran [email protected] with only 2600 RPM stall and tall rear ratio at 3.25 with puny 225/50-16 DRs on all four corners (full Exh exiting at rear bumper)
I rode in it drove it a happy little combo for sure !

My brother provides a have dozen track cars for practice for the major Nascar teams running at west coast tracks, He has a couple engine teams that can drop ship serious power and its his job to set up the cars.

He gave Stoker 2001 a little help on handling issues

Give me a Pm and I will give you his #
 

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Resident Ford Nut
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Discussion Starter #19
who do you use for porting heads and intake as i would like to do mine soon as there is defiantly some power to be had?
I use a guy here in town I've known for nearly 20 yrs. He ported the heads for Crower's Engine Master's engines.... he eat's, breathes, sleeps air-flow. He mostly ports heads for 250-450cc four stroke bikes and quads now, but will still port a head for me when he has time, Geoff Mummert is his name.

Give Foxwell a shout, the guy does know what he is doing. His location might even be close to you.


S CP
 

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Resident Ford Nut
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Discussion Starter #20 (Edited)
up-date:

pull 5 today


pull 6



Started with 495 as it came out of the car. Fresh head gaskets, freshend up heads and springs and new bearings.

first pull had 32* timing and then bumped it to 34* and picked up 10 hp, bumped it to 36* and picked up a couple lbs ft at max trq and 2 hp.
At the end switched from a 1" open spacer to a 1" 4-hole Super Sucker and picked up 5 hp ( 540 vs 545) last pull at 550 made a change to the air flow in the dyno room and made 550.


Ready to go back in the car and get it to rev 6,800 and see if the Stang can top 190 mph this year. Not a bad running 342. I hope we don't split the block this year.....:)Unsure

S CP :wink2:
 
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