'68 Turbo Project with 347

[seaya67]

Have a '68 resto mod in process.... have a 347 long block with a .576 Lift Comp Magnum Cam. Already has shock towers removed and Mustang II suspension installed and 4 Link with Coilovers in the rear.

Want to install twin turbos carb setup, but wondering if it is even possible and still maintain all the amenities my wife wants on the car (Power Steering and Air).

I can have the local shop fab almost anything up, but looking for help on all the down and dirty details....
1. Carb brand and size (Barry Grant??)
2. Where to get a good looking Bonnet
3. Blow-off Valve Pressure
4. Turbo Recommendations
5. Intercoolers (Plan on Fabing the stock front apron) Need to keep the tags for Illinois, so may need to go with twin intercoolers.

Additionally, Comp Cams recommend carb only for the cam. Will I have any issues going turbo.... Any help would be appreciated.


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[iskwezm]

make sure the cam is a wide LS, and dont use a TIAL wastgate,no Barry Grant carb, and Extreme Velocity bonnet.

Ask 10secgoal about a complete kit or just the headers/hot side
View attachment 255589

 

[classic boost]

why not use a tial?

 

[mrmustangman357]

some people have had problems with tial not flowing what they should IIRC


why not go efi if it is turbocharged?

 

[10secgoal]

why not use a tial?

Their customer service is something to be desired. And their 38's won't control dick anymore. Just had boost creep on a mild 302. Saw 13 lbs with a 6 lb spring. Hopefully a JGS 40mm is going to fix it.

PS, do not use a BG for blo thru. They are lean N/A, god forbid bl thru

 

[blown65]

X4 on the BG carb, I wont buy anything BG related.

Personally I'd go with a Prosystems carb from Patrick, I have three of his carbs now and everyone of them have been great.

 

[classic boost]

the word is- patrick doesn't have blow-thru nailed down. but i don't have any 1st hand experience with him.

 

[classic boost]

Hopefully a JGS 40mm is going to fix it.

my friend had a jgs 60mm and it didn't work for ****. he went back to his 44mm tial and worked fine.

 

[blown65]

the word is- patrick doesn't have blow-thru nailed down. but i don't have any 1st hand experience with him.

ah, mine are all N/A so haven't dealt with him on blow thru yet. His customer service is great however and will do what it takes to make things work right.

 

[seaya67]

I am just getting into this... iskwezm.... is that your car on youtube where you have the camera in the car runnin through the gears? That car sound awsome... Also thought you would get more HP from a stroker & turbo.

The rest of my Stroker engine.
Cam is for a 351 firing order. 304 Grind
Cast Iron World Heads (Windsor Sr. I believe) which are o-ringed
Super Victor Intake
Gear Drive timing

Don't have a carb yet and doing research on the air system....

 

[seaya67]

More on the Cam

RPM Range 3000 to 6500
Valve Timing .006
Lobe Center Angle 110
Intake Centerline 106
Duration 304
Duration at .050" 244
Valve Lift .576
Lobe Lift .361

Will this cam be okay given the heads....etc...

Or should I give up on the Turbo and be happy with the Stroker?

 

[seaya67]

One other question.... Don't see intercoolers on all setups. Are they required?

 

[iskwezm]

I am just getting into this... iskwezm.... is that your car on youtube where you have the camera in the car runnin through the gears? That car sound awsome... Also thought you would get more HP from a stroker & turbo.

Due to having a f-ed up $$$$ carb from PERFORMANCE CARBURETOR IN ONTARIO,CA, we spent most of the day getting the carb near stock to start tuning.We started to kill the clutch and really didnt get into an A/F higher then 10.4 or 18*. I dont think the dyno reading correctly and had tire spin too.My cash was running low and didnt want to glaze the clutch more then it was.

My other cam was similiar with a 108 LS and it was bleeding off cylinder pressure.Now i have a 115LS .599 lift, pretty nast cam.

 

[brianj5600]

seaya67, how much power are you trying to make? What block do you have? IMO a single 70mm is a bit small for a 347. A T-76 gts like classic boost had would be the ticket for a single. If you have a stock block you will never realize the potential for turbocharging. It will be way more fun than any stroked small block. My car went 6.90's in the 1/8 on pump gas and driving it to the track on 3.08 gears and radials. My cam has 16* less at .050" and only .512 lift. It would be tough to get a stroker into the 6's with out putting in some unfriendly street gears.

As for the cam it is far from a turbo cam, but there has been some people get good results with N/A cams.

 

[10secgoal]

Due to having a f-ed up $$$$ carb from PERFORMANCE CARBURETOR IN ONTARIO,CA, we spent most of the day getting the carb near stock to start tuning.We started to kill the clutch and really didnt get into an A/F higher then 10.4 or 18*. I dont think the dyno reading correctly and had tire spin too.My cash was running low and didnt want to glaze the clutch more then it was.

My other cam was similiar with a 108 LS and it was bleeding off cylinder pressure.Now i have a 115LS .599 lift, pretty nast cam.

Yeah, don't think it was 100% accurate either. Cars with 400 rwhp don't spin the tires at 50 mph

 

[seaya67]

Looking to make 600 hp. Would like to go twin turbo, unless single is better. Going for the "wow" factor for the car.

I bought the short block used (1000 mi) and the cam was new in a box with it. The engine is at the machine shop getting checked out this week. It is not a boss block, but does have a girdle.

What does a "turbo cam" look like?

 

[10secgoal]

Less overlap than N/A cams. But generally not very big. Building one right now and looking for somewhere on the 700rwhp range on 91. The thing is only 540/542, 226/220 @ .050. Looks a good bit like an X-cam, but a 114 separation and 110 centerline. The X is like a 107 center, and I'm sure the separation is lower also.



Paul, was your buddy running a BC ? I know they generally come with soft springs.

 

[seaya67]

Am I reading your durations right?
226 Intake and 220 Exhaust with a 114 LSA

I found a overlap calculator, and it says that is a -5* overlap.

My cam gave me a 84* overlap.

 

[seaya67]

Scratch the overlap calculation... re-calculated it is 25* overlap.

iskwezm's old cam (108 LSA with 244* Duration) had around 28* overlap. He said it was bleeding off pressure....

Wouldn't larger turbos or larger single turbo improved the condition (Lesser Back pressure)? Secondly, how did you like that set-up overall...?

 

[10secgoal]

Your reading them right. If you have over lap with a boosted motor the incoming charge goes out the exhaust while the valve is open, until it closes. So that's why they tend to make less HP up top. the higher the RPM, the less time from the point the exh valve closes until it actually starts to pack the cyl.

The turbos will effect back pressure, but nothing to do with overlap.