Looking for Idea/advice on build

a91what

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Mod Dude
Apr 6, 2011
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#1
As many of you know, my luck has not been very good lately. After working with what was possibly the worlds worst machine shop, I am left with an engine that keeps eating itself. Before i jump off the deep end I need some direction for the car.
Some things you should know.
- Car is a convertible-
-Car has weld in SFC
-still 4 lug
-have the MM STB
-I want to install a 4 or 6 point roll bar with low slung door bars
- has a solid T5 in it
- The engine is a stock block 306 with forged pistons, Heavily modified GT40 Iron heads, and a custom M112 blower running 12PSI.. with all the needed supporting mods to make 600HP

Im not sure if i should spend a bunch of money and buy a dart block to bulletproof the engine or spend that money elsewhere...
If this were your car what would you do?
 
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90sickfox

I didn't really have an issue with the stink...
SN Certified Technician
Mar 2, 2015
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#2
The roll cage will help a bunch in a convertible. On mine I wish I would've ran tubes up to the back of the the strut towers. My cage seemed to isolate stress at the front of the door openings and in the passenger corner of the cowl.

A Dart or Boss block would be awesome...wouldn't have to worry about power levels cracking the block.

4 lug means 4 lug brakes....I'd definitely upgrade the brakes. It's not expensive or hard to do. I'd stick with fox length rear, unless IRS. Seems to be too many wheel fitment issues with the wider 8.8 rears. I like the look of a deep rear wheel. The wider the rear, the closer the face has to be to the outside of the rim. These things you know.

The Dart will need lots of machining and a good machine shop....but totally worth it. Seems moot without good brakes to stop the car when it has 600hp.

With th he cage just think about it like this...

Stress is stresss... whatever you stiffen just transfers that energy somewhere else. If doing a cage I'd go to a 12 point with low or swing out doors bars. Make sure it's high enough to tuck up in the top away from your noggin without looking stupid. Tie the strut towers to the cage. You can do it and keep all the HVAC stuff.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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#3
I'm a budget, I just want to drive it when I want, reliable ride that can spin the tires when I stand on it kinda guy. I would fix the block you got, the damage may not be that bad. Stick it back together with the stuff you have worked so hard on and spend the dart/man-o-war block money on the brakes, roll bar (I have a love/hate relationship with roll bars in verts), garage build and the hippy wagon.
This way you can have a fun time cooking the tires in the vert when you want too and keeping an eye out for that 'deal of the day'.
i'm also an older guy with a new garage to finish up, 3 projects sitting and a the 'dump truck' to maintain.
 

a91what

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Mod Dude
Apr 6, 2011
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#4
Thats good advice, but if this were your car what would you do first? and would you take the engine to a different shop to salvage what you have now while doing all the other upgrades/mods
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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#5
If you're asking me I would talk to the azzhat that worked on it first then take it to another shop. The first shop may have just had a bad day and will make it up to you money wise, depends on what went sideways. Ask around a few shops, I can put you in contact with the guys that do our work at the shop but it's a ride from your crib.
 

RangerJoe

I leave the horn on while driving
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Apr 26, 2010
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#7
what do you guys think of a 4.6l swap?
I think your brake and suspension upgrades need to happen.....but, playing with a stock block these days is pointless ( I am too) considering 500hp is barely exciting anymore. As for a 4.6 swap, i just don't see the benefit of all the work for old technology. The blocks are strong, but the rotating assembly isn't much better unless you get a termi shortblock.

Joe
 

90sickfox

I didn't really have an issue with the stink...
SN Certified Technician
Mar 2, 2015
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#9
No to the 4.6 swap....

The best route would be to pull the engine ( again ) and find out what it needs. Im a strong believer in the fact a car has to be able to move under its own power first. I know your car runs now but...the build will go a lot faster when you know the engine is solid.

No since kicking the can down the road if you don't know vx what it's going to cost you. You could spend 600 on brakes and 5 lug...and turn around and find out your block is trash...or find out the block is good with a line hone and roll forward with a couple grand to spare.

If you stretch out too many things at once it'll take forever to get done.

Engine, brakes, roll cage - or stifflers spider brace, then other stuff. I threw the spider brace in there. Ive seem that thing on a few convertibles. Ties the car together very well. Cages can look weird in convertibles.

20190125_121255.jpg
 
Jul 7, 2005
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#10
You already know my answer Steve.....

I still believe that you need to put the money into the Dart or Man of War block just for the reason of you have the sickness that most of us have. You will be good with the 10 psi you have now but a month later (or less) you will want to add more or change the combo to a turbo or a turbo/m112. Starting with a good block means you dont have to touch any part of the bottom-end to make any changes in the future.
 

Steel1

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Aug 18, 2017
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#11
Since it seems like machine work around you is sketchy why not have Fordstrokers build you a short block,
then you can bolt up your intake/head combo. Never heard any complaints about their work.
Chassis stiffening is a must, as far as brakes go if it's a street only car you could upgrade what you have
rotors,pads,caliper sleeves lines, MM rear shoes etc. also will save the expense of new wheels.

Honestly if it were my car I would do what I've already done.....351w based stroker, but I know you put
a ton of work into your s/c set-up for an 8.5".
 

95BlueStallion

You drunk?
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Feb 22, 2007
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#12
I'm a budget, I just want to drive it when I want, reliable ride that can spin the tires when I stand on it kinda guy. I would fix the block you got, the damage may not be that bad. Stick it back together with the stuff you have worked so hard on and spend the dart/man-o-war block money on the brakes, roll bar (I have a love/hate relationship with roll bars in verts), garage build and the hippy wagon.
This way you can have a fun time cooking the tires in the vert when you want too and keeping an eye out for that 'deal of the day'.
i'm also an older guy with a new garage to finish up, 3 projects sitting and a the 'dump truck' to maintain.

This.
 

RaggedGT

Not a very good Mod
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#13
If we are swinging for the fences- 427w dart :D
On a more budget friendly note, why not see what’s hurt in the current motor? Maybe a cylinder hone and a new set of Rods and bearings will have you scaring JDM kids in Florida again
 

a91what

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#14
Since it seems like machine work around you is sketchy why not have Fordstrokers build you a short block,
then you can bolt up your intake/head combo. Never heard any complaints about their work.
Chassis stiffening is a must, as far as brakes go if it's a street only car you could upgrade what you have
rotors,pads,caliper sleeves lines, MM rear shoes etc. also will save the expense of new wheels.

Honestly if it were my car I would do what I've already done.....351w based stroker, but I know you put
a ton of work into your s/c set-up for an 8.5".
Car already has lines, pads, rotors ect... for the 4lug... it still does not stop well enough for my driving style, car is full weight.

I always build my own engines, the cost to outsource the entire thing including assembly is crazy. Engine assembly is very straight forward take your time and follow the spec.
 

Boostedpimp

10 Year Member
May 8, 2003
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#15
You've accomplished allot with your car. You've done some pretty cool stuff we've all seen it here. So I would say simply open that big, beautiful warm, and inviting pocket book of yours up and share all your riches with the lovely people of Dart inc.

Pretty sure it would make each drive out in the car an enjoyable one.. No more stressing over the integrity of the block and if it will go kaboom if you over boost a tad :)
 

Steel1

Advanced Member
Aug 18, 2017
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#16
Car already has lines, pads, rotors ect... for the 4lug... it still does not stop well enough for my driving style, car is full weight.

I always build my own engines, the cost to outsource the entire thing including assembly is crazy. Engine assembly is very straight forward take your time and follow the spec.
You are correct, you may have answered your own question.
Engine assembly is very straight forward with competent machine work, I enjoyed building mine.
Seems like 5 lug upgrade is a must for you so guess the only question is stock block or not.
With the power levels your talking about I can't see a stock block lasting very long, aftermarket block
seems to be the way to go.
 

CarMichael Angelo

I don't like your attitude, let me fix that.
SN Certified Technician
Nov 29, 1999
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#17
you don't have anything that'll transfer over to the dart block except the pistons. Stick the same cast crank, and rods back in to a different high dollar block, and you'll be right back where you are presently. Whatever is wrong with your combo is directly related to the recip assy.
An aluminator 4.6 engine combo is a stupidly expensive swap.
4 cams, heads that have to be modified to get rid of some of the factory fuel distribution measures, all cast internals, it won't fit your trans, and after all of that...is still the largest space taken up by 281 cubic inches on the planet.
a 351 was my advice several pages back, and it still is. They're all over the place, your heads, although inadequate will fit, as will your Cam. Your trans will swap, and dimensionally, it fits your car with room to spare.
Ditch the 5.0, even if you buy the dart block, you'll be cheating yourself by stuffing in a potentially bad rotating system. And, by the time you spend that money for the block, you could buy a jy 351, and the upgraded internals to withstand 750 HP forever.
dump the blower, buy a chinee turbo..
Use what you got to build a hot side , and be done.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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#18
I agree with mike on a couple things, 4.6 blaa blaa been done, 351 and a chinee hair dryer? blaa blaa been done, now a 5.0 and a m112, custom intake with other backyard built crap that can fry the tires with 10 lbs of pressure stuffed into it, that is not blaa blaa anywhere you look. Only a few can pull that off and your on that list, fix the engine, turn on the ac and enjoy the ride.
 

CarMichael Angelo

I don't like your attitude, let me fix that.
SN Certified Technician
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#19
I agree with mike on a couple things, 4.6 blaa blaa been done, 351 and a chinee hair dryer? blaa blaa been done, now a 5.0 and a m112, custom intake with other backyard built crap that can fry the tires with 10 lbs of pressure stuffed into it, that is not blaa blaa anywhere you look. Only a few can pull that off and your on that list, fix the engine, turn on the ac and enjoy the ride.
All the unique in the world doesn't change the fact the a stock block 5.0 was never intended to handle 500 ft lbs of torque. Couple that to the fact that that Eaton probably doesn't like compressing water/meth, was already showing him fuel distribution issues, and upping the boost requires a new belt and pulley (s) and one way or the other, this space ship is gonna end up with " Houston,.....we have a problem".
Hell for that matter he can keep the Eaton on the 351, but that would require making intake manifold spacers to adapt the current intake, and some new bracketry on the front. In the end, compared to the fabrication to make the turbo work, it may be the lesser of two evils. But In my experience, adapters and spacers where oil/water/and air move past increases the potential for a leak of one, or more of any of the three.
A 351 crank is capable enough stock to just prep it and leave it in the block. Better Rods are cheap enough...
image.jpeg

300 bucks.
Another 500 gets him a .030 + set of 4030 alloy forged Pistons, pins, locks, and rings..
wis-pts500a3_sn_xl.jpg

I'd just about challenge anybody here that I could build this engine short block for the price of a bare Dart block, and have new bearings, timing chain, oil pump, pan, and machine work all in.

*edit...for another 300 bucks, the intake adapter is already out there..
AP-03Wweb.jpg


The chassis can be dramatically stiffened with a good set of SF connectors like what I, Dave, and the other guy that overbuilds things have done. Add a side to side floor brace, that ties each side together and you will dramatically stiffen the car.
A roll bar (not cage) in a street car makes for even better side to side stiffness..But add door bars....and you'll hate yourself for doing it. Swing out bars are noisy, dangerous, and the fact that they aren't solid offers jack when compared to the solid versions. Low bars are better than nothing, but anything you do to make it a more safe drag car, makes it a less safe street car.
( drag cars don't typically get t boned at intersections,....t boned door bars make for really good broken legs, and hips.)

Brake upgrades on a street car are overkill....how many times have you been on the street in your present car, where your existing brakes failed to stop your car?
The only reason I upgraded my brakes was because I wanted 5 lug wheels, and it made sense to switch to a bigger brake as a byproduct.
 
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