I've officially decided to go turbo on my 68

DarkoStoj

Founding Member
Sep 4, 2002
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Detroit
Where's my hoes 10secgoal, paul302, and xoxbxfx :D

I've been throwing around the idea of what I want to do with the motor for quite some time now. I've thought about every combination of n/a, nitrous, and boost and have been back and forth on just about everyone. I want to be able to make a lot of power, and be able to drive it whenever I want. I'm not going to be able to work on the car for a few months since i'm not at my house so I just look through the internet and keep changing my mind on what I want to do. I have a great rust free 68 J code fastback to work with. I bought it with a fresh 306(original block), and I have a tremec 3550 trans that I threw in since it was sitting in the corner of my garage just waiting to be used in something. Also have a 9" to go in, but uncertain about gear ratio.

Here is what I'm starting with.
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The motor is a 306 with eagle I beam rods, TRW forged pistons(L2482F30), and WW sr. heads milled to 62cc with some mild porting....not my choice of motor to run, but it came with the car and it has never been fired.... I figure it will work until I get the r302 block. Right now its at 9.5:1 compression, I'm thinking it might be a little high since I want to run on 93 octane.

This is going to be a little tough and frustrating since I'm relatively new to boost (but not fabrication), and the motor is going to have full accesories (p/s, alt, HUGE factory a/c compressor, p/b), there isn't much room in the engine bay, and I'm not going to cut any of the metal since the car is rust free and I want to keep all the origional metal intact.(or cut very little if I have to :D) I've been reasearching at a steady rate, but there is so much info its just overwhelming at first. Just about everything will be custom and fabricated by me including the headers, piping, brackets, etc.

My goal is to get ~500rwhp with this block(I hear the 68 block is beefier then later 5.0L blocks) or maybe 450 because I really don't want to split the original block. When I get a r302 block at 331ci with AFR205 heads I don't want to have to change any of my setup except the longblock. I'd hope for ~700-800rwhp....or even more. I think a garrett GT42 or a turbonetics T76 single turbo with EFI will be good for what I'm looking for? I really have no idea since I just started to learn how to read turbo Map's :shrug: I'm going to have a good budget, but I want to make sure I have enough money for the suspension, chassi stiffening, etc. instead of blowing everything on the motor.

I'm a little worried about getting over my head, but I think a turbo EFI 68 fastback would be the coolest car on the planet :hail2:
 
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keeping all acc and no cutting is a tall order indeed. a gt42 will make the power, but it's a big turbo physically. i can't see any way imaginable that you will be able to make something work with your restrictions.
my suggestion is to go with a novi2000.
 
I've been looking at it, and I think I found a way to do the P/S, A/C, and all that junk(although it may cause a little lag in spooling time). But with the A/C, unless you get extremely detailed, and are willing to lose alot of material to experiment, it probably won't happen.
I've basically got the same goals as you, but I may go 351w for cost reasons. I want to replace the shortblock, and go to a better intercooler. Otherwise I wouldn't have run one at all. Unless you go with a ton of meth, you are probably going to need to relocate the condensor to make room for an IC
 
i too am building a single turbo car. ive seen twins on a 65 but no acc. i loosing all of mine. your gonna have a hard time making your setup work with what you want. but good luck. btw a t76 can support about 1k hp
 
oh yeah gears all depends on tires and if your taking it to the track. tranny to. im gonna be running either 3.10s or 3.25s with my c4. on a 26" tire that should give my a good mph and decent hwy rpm. but higher gear is better (more load less lag)
 
what about a Precision 76 GTS turbo, it uses the exact same compressor and turbine wheels as the gt42-76, but it's in a smaller package with a T4 flange, its setup for a smaller downpipe so that will also help with packaging.

I'm sure It would all be able to fit if I get creative.
 
yea, i've already looked through your pictures more times then I care to count, very nice install. It's going to be way more difficult for me to get everything to fit though. I plan on running EFI, an intercooler, and stainless for the plumbing.

Just curious what specs you have on your motor, and what the 76 GTS turbo is capable of power wise? The smaller the turbo is physically, the easier it will be to get shoe horned in there. :D
 
Definitely keep us posted on your progress I think having a classic with a turbo is very cool. I do have a couple of general questions to all the experienced builders……

What do you think the cost difference is between building a Turbo 351 that can make a 10 sec pass and a building a naturally aspirated motor that can do the same? This is assuming you already have spent the money on all your other parts to accommodate the motor.
 
One plus for a turbo is that highway friendly 3.00 gears work well. A 10 second n/a motor needs high numerical gears, 4.11 or even 4.56, meaning you'll need an overdrive for anything more than a trip to 7/11. You should be able to get into the 10's with just good pistons, any aftermarket heads and a good turbo.
 
brianj5600 said:
One plus for a turbo is that highway friendly 3.00 gears work well. A 10 second n/a motor needs high numerical gears, 4.11 or even 4.56, meaning you'll need an overdrive for anything more than a trip to 7/11. You should be able to get into the 10's with just good pistons, any aftermarket heads and a good turbo.
i got a 5 speed so the steep gears really wouldn't bother me. I'm so excited about getting this project going!!! I finally got enough cash where I don't have to worry about it, so I'm going to make this happen.

Hey 10sec, I went through your thread and all the pics of your setup werent loading, you think you could post a few? What turbo did you go with?
 
Doh, mine are too big. That's why I gave them to Jades. PM me your addy and I'll forward the ones I have in my email. I have them all there. But te ones I have sized, are too big. I make cars fast. Not computer literate.
You might want to look into a tranny swap at some time later also. Turbo don't especially like sticks.
 
10secgoal said:
Doh, mine are too big. That's why I gave them to Jades. PM me your addy and I'll forward the ones I have in my email. I have them all there. But te ones I have sized, are too big. I make cars fast. Not computer literate.
You might want to look into a tranny swap at some time later also. Turbo don't especially like sticks.
why don't they like sticks? I don't know what I would do w/o one. My email is [email protected] if you want to send them my way.

Is EFI a better way to go then blowthrough? What about tuning it? Would I have to get a custom chip burned or what? What about hooking my laptop to it to make sure it flashed "Danger to manifold" if I have problems to make sure I don't blow the welds on the intake
 
Anyone consider rear mounted turbos? I know alot of the newer cars that are turbo'd have the rear mounted ones. I don't know jack about turbos but thought i would toss that in, since you would be able to retain your accessories with rear mounts.

Another idea is to make custom accessory brackets, say to move the A/C compressor to directly above the water pump and possibly relocate the PS pump. Just another idea if you have some fabrication skills. There is also a company on the web that has a software program that you can download and design your own custom piece. The software will then give you the cost of them making the piece out of the material you specified.

Also, aren't alot of the Type R and ricer turbo cars stick shifts? :shrug:
 
stirling33 said:
What do you think the cost difference is between building a Turbo 351 that can make a 10 sec pass and a building a naturally aspirated motor that can do the same?
i think the turbo combo will cost more simply because of the cost of the turbo, bigger fuel pump, and bonnet. the advantages of the turbo is- lower required engine rpm, less gear, less cam, and less compression. basically, a 10sec n/a car is going to need a big cam and alot of gear, where the turbo combo would be a mild docile grocery getter engine, and still run the 10's.

Turbo don't especially like sticks.
i don't think that's an accurate statement at all. sure, an auto will load the turbo and give you a better et, but that doesn't mean turbos don't run great with sticks. my incon car ran great with a stick, it was a blast to drive. if i had to do it over again, i would put a stick in my '68 in a second. MUCH more fun, and you don't have to worry about the converter bullchit.
 
paul302 said:
i don't think that's an accurate statement at all. sure, an auto will load the turbo and give you a better et, but that doesn't mean turbos don't run great with sticks. my incon car ran great with a stick, it was a blast to drive. if i had to do it over again, i would put a stick in my '68 in a second. MUCH more fun, and you don't have to worry about the converter bullchit.
I don't think it's that far off. How many guys leave the line full tilt with a stick ? I'm not saying it won't work, or be a blast. But one will be faster.
 
DarkoStoj said:
I think a turbo EFI 68 fastback would be the coolest car on the planet :hail2:


Yeah yeah me too.:nice:

Don't worry about getting in over your head. There are lot's of guys willing to help out. I am sure you have spent some time over at www.turbomustangs.com and found that they are very helpful. Read, read, read and read some more and before you know it you will be able to jump in with both feet. Make sure you are very aware and firm in your objectives for the car before you start. If you don't know what your desires are it will send you down the road of despair fairly quickly.

Some questions to ask are:

How much time will you spend at the 1/4 mile?
How fast do you want to go in the 1/4?
How many mile do you plan on driving the car annually?
What tires and wheels are you going to run?
Are you ever going to do autocross type events?
What about suspension modifications?
How about the chassis mods?
Do you just want the 'bling factor' (for lack of a better term) WOW a turboed classic?

Hopefully you can see what I am getting at. It's the complete package not just a hairdryer and a computer. You can slap a turbo on any car but without the complete package you end up spending a ton of $$$$ and most likely it won't provide the satifaction you are looking for?

Just my $.00000000002