Modding a carbd 302.

LaserSVT

Got FB banned again for saying nards
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Nov 29, 1999
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I have pretty much no experience with carbs at all and had some questions about what works on, oh I dont know, a 85 GT.
If you wanted to make some nice streetable power with it then what would you mod?
Like would you just get some AFR 165s? Whats better, stud or pedestal? What about cam and rockers? Is it the same profile you would use on an 87-93? Would you use 1.7 roller rockers? Are the pistons flat tops and require cutting to clear a larger cam? I dont mean a radical cam but like a mild street cam.
What about the carb? Is the stock carb decient, just re jet it for the new heads and cam?
Then the exhaust raises another question. I see LMR does not have a cat back for them? :scratch:

What kind of power can be expected?


No, I am not buying one. I am just curious about how well the 85 takes to mods and what works best for them. :nice:

Thanx Stangnet! :SNSign::flag::hail2:
 
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Hey...another 4-eyed guy:cheers: What kind of power are you looking at making? The mods in my sig make good power for a budget minded build. I have not got to take it to the track yet but I figure it`ll turn low 13`s. Is yours a roller block or flat tappet? It all depends on what you want to do with it but it is easy to make power with our carbed ponies!:nice:
 
Hey...another 4-eyed guy:cheers: What kind of power are you looking at making? The mods in my sig make good power for a budget minded build. I have not got to take it to the track yet but I figure it`ll turn low 13`s. Is yours a roller block or flat tappet? It all depends on what you want to do with it but it is easy to make power with our carbed ponies!:nice:
Reading the whole post would be good :nice:

Did you have to fly cut the pistons to clear the valves?
 
I forgot, ive seen a few with 140 MPH speedos in them. Does the aftermarket make them or do you have to find a SSP one?
 
Man look no further than my old combo. The same principles apply as with EFI, only more simple and less parts to buy and less money to spend. The kicker is in learning to tune the carb which if you take seriously and TRY to learn it, it's childs play. Your dad and grandfather grew up with carbs...they're simple to work on as long as you do it right.


For cheap 12 second power (you can just about skip 13s altogether), get yourself some P heads, a Stealth intake and a 650dp, and follow it up with a healthy cam like the TFS Stage 1 (the Stealth/Stage 1/GT40P/650dp combo ROCKS). Do the usual headers/exhaust/short belt/gears type bolt ons and that's about all you really need to go mid-high 12s unless you're driving a '87+ GT vert with an AOD.

A couple things i'll just throw out there:

1) I wouldn't buy ANY duel plane intake but the Stealth. NONE.

2) I wouldn't run an Edelbrock carb if it was given to me along with the money it cost to buy it.

3) Go to Holley's website and order their tuning DVD...it's idiot proof and will show you how to change jets and set float levels...it's a great introduction to tuning and being a DVD makes it super easy to follow.

Those are my own personal opinions, but they're tried and tested.
 
A friend of mine has a carbed 88 Coupe with Twisted Wedge heads, roller rockers, a .512/.509 cam (i forget his duration), with a performer RPM and a 600 carb on a stock bottom end.

With drag radials, 4.10's and a five speed, it flies!

I'm sure he'll chime in soon. Where are you 306Notchback?
 
This is great info guys! :cheers:

Now 12's are great but since I prefer to road course race and have decient highway manners I would prolly do 3.55s if I were to build one.

So with GT40Ps, a TFS cam, Holley 650, Stealth intake manifold, long tubes, catted x-pipe, cat back and a hot ignition what could I expect for rwhp?

Also, what does an 85 T-top weigh in at?
Any info on the 140 mph speedo?
 
If you search long enough in junkyards you can find the 140s. A buddy of mine just found TWO of them in the same damn yard.

As for power numbers....judging by my old 302, i would say with the P heads at least 250 at the wheels, maybe as much as 270. The heads i have flow more than P heads and have larger valves....when i swapped over the short block for the stroker, it make 362hp...i can't imagine just swapping to a 347 and a bigger cam netted me 100 more horsepower at the wheels, so my old combo HAD to be making at least 265 at the wheels, probably closer to 300hp.
 
mump_0710_05_z+1986_CHP_SSP_ford_mustang+140_MPH_speedometer.jpg
 
Hmmm. Must've been something available aftermarket - maybe FRPP. Far as I know, Fox Mustangs didn't have anything more than 85 MPH speedos stock until '89. My '86 GT 'vert had the 85 MPH turd, and my '84 has the same thing. :shrug:

I WANT THAT STEERING WHEEL. :drool:
 
Man look no further than my old combo. The same principles apply as with EFI, only more simple and less parts to buy and less money to spend. The kicker is in learning to tune the carb which if you take seriously and TRY to learn it, it's childs play. Your dad and grandfather grew up with carbs...they're simple to work on as long as you do it right.


For cheap 12 second power (you can just about skip 13s altogether), get yourself some P heads, a Stealth intake and a 650dp, and follow it up with a healthy cam like the TFS Stage 1 (the Stealth/Stage 1/GT40P/650dp combo ROCKS). Do the usual headers/exhaust/short belt/gears type bolt ons and that's about all you really need to go mid-high 12s unless you're driving a '87+ GT vert with an AOD.

A couple things i'll just throw out there:

1) I wouldn't buy ANY duel plane intake but the Stealth. NONE.

2) I wouldn't run an Edelbrock carb if it was given to me along with the money it cost to buy it.

3) Go to Holley's website and order their tuning DVD...it's idiot proof and will show you how to change jets and set float levels...it's a great introduction to tuning and being a DVD makes it super easy to follow.

Those are my own personal opinions, but they're tried and tested.

good advice here +1 on the holley DVD also

came with my 650 double pumper and found myself referring to it a number of times :nice:

View attachment 256004
 
Ok! I see how much our experience counts!
Uh, thats why I am asking. If I wanted more then 260 rwhp AND want to save weight by going to aluminum heads but not drop $1500 on some AFRs then would those be better then GT40P's?
What is the best combustion chamber and runner size for a 302 with the possibility of it being pushed to a 331 down the road? I was thinking 58cc and 180cc for N/A.
Also, is the Holley 650 DP enough for those goals? Is the car set up for vacuume secondaries?
IDK what that is but see mechanical and vacuume. I also assume the car uses an electric choke :shrug:

What is the best cam to get that keeps the car civil? The TFS stage 1 or one of the Ford 303 cams?
 
Im running an edelbrock performer rpm lower intake, Holley 650 double pumper, GT40P heads and a F303 cam, I did run the tfs1 cam and it was very streetable and behaved well at low rpms too. (A/C and all) Ran it for a year in Atlanta stop and go traffic...the Weiand Stealth is a great intake also...probably a little better than the one I have actually