help with 351w swap

[jayh]

I shouldnt even have brought up the 351 marine engine because I wasnt sure
any mid-late 80's 260hp mercruiser(350) comes with a 750 quadrajet
any mid-late 80's 270hp volvo penta(350) comes with a 750vs holley

when I read 32" tire, my first thoughts were 22" or 24" rims, not my taste, but some people like it

I currently own a 2400stall in an AOD. its a piece of dogshit, (with a 3.73gear) the car wont cut any better than a 2.0 60' it cut the same 60' with a stock converter. I owned a 3800 stall with a c4 and 3.73's and drove it daily for years

most AOD guys with hopped up mustangs run a 4.10 gear, with 26"tires. actually, if you take a tape measure and measure a 225/60/16, a 225/55/26, or a 245/45/17 they all come out to around 25". even a 245/50/16 or a 275/40/17. I have owned all those sizes, the first 3 are stock sizes. going from a 25" tire to a 32"tire is a BIG deal

3000-3500rpm stall for a 4000# daily drive will actually make it less fun to drive. It may help your launch at the drag strip but it will only hurt you on the street.

please explain this statement...

[Mercracer]

3000-3500rpm stall for a 4000# daily drive will actually make it less fun to drive. It may help your launch at the drag strip but it will only hurt you on the street.

please explain this statement...

Once your car is moving you do not need as much stall to accelerate. If you are driving along and hammer the throttle, your rate of acceleration can be less with a higher stall than a more conservative one if what you hve is a conservative cam/engine. A 302 with an HO cam simply does not need nor can it take advantage of a 3500RPM stall converter on the street.
Few cars on this board are dedicated drag racing vehicles. Most all are street cars with occasional trips to the track. Most are also daily drivers. What "feels" cool is not always what will perform the best.

[Mercracer]

I currently own a 2400stall in an AOD. its a piece of dogshit, (with a 3.73gear) the car wont cut any better than a 2.0 60' it cut the same 60' with a stock converter. I owned a 3800 stall with a c4 and 3.73's and drove it daily for years

most AOD guys with hopped up mustangs run a 4.10 gear, with 26"tires. actually, if you take a tape measure and measure a 225/60/16, a 225/55/26, or a 245/45/17 they all come out to around 25". even a 245/50/16 or a 275/40/17. I have owned all those sizes, the first 3 are stock sizes.

Were you running factory shocks/springs and street tires? A Mustang starts out with a HO motor. 3.73s perform well in stock Mustangs. Most guys with "hopped up" Mustangs will change the cam and many go alot further with mods.
Everyone needs to keep perspective. This isn't a dick measuring contest. It isn't about what you can tolerate but what will perform the best in the application you are using it in. Performance from 30 to 50 and 55 or 65 to 80+ are practical considerations on the street in addition to zero to whatever.
As a real world example, if someone with the identical combination as you (with the exception of a standard transmission vs your loose converter) pulls up beside your car as you are traveling 40MPH and you both hammer the throttle, the other car will pull away. Your loose converter will hurt your performance.
Please keep in mind this thread is focusing on someone who is doing their first project.

[Mercracer]

Here is the other piece of the puzzle that many people ignore. You shouldn't go extreme on one part of your combination in order to make up for the shortcomings of another piece. The first thing anyone should buy for their car is a set of Drag Radials or a set of "slicks". Going to the track with "street" tires is just silly if you are spending several hundreds or even thousands of dollars on other parts of your car. Focusing on your converter for your 60' times and not looking at other things is a waste of money. If a 3400lb Mustang can pull off a 13.8 with a factory converter, a 4000lb CV should be able to pull off a 14.0 with a mild converter.

[jayh]

as far as the car in question, it transfers weight really well, if its not spinning, then its not spinning, I floor it right out of the hole. it still has a stock HO cam in it, but it has brodix aluminum heads, 1.7 rockers, gt40 intake, full exhaust, and a blower. it doesnt come out of the hole because the converter sucks, it does not spin the tires

as far as the converter hurting performance from a 40mph press, in my personal experiences, you are wrong. there is no other way to put it.I went from a 5spd to c4 with 3800stall. I had 2 friends what were extremely close in performance to measure before and after, as well as a stack of timeslips. testing was done out of the hole, 30mph press, 45mph press, 60mph press. the looser converter does not hurt performance; maybe in theory, but not in real world testing. the looser stall puts the motor in its powerband at all times. not a hard concept to grasp that when you wind the motor up it makes more power

a loosened up stock converter is a piece of crap, while it might seem cheap, they are actually a waste of money. you are correct, this is not a "dick" contest. my suggestions would be to become a member at www.clickclickracing.com and learn more about performance AOD setups. the 2 big gurus over there are both lincoln markvii guys, so you cant say it only applies to mustangs

I agree with you about traction, power is useless if you cant put it to the ground.

[1980c10]

Are you talking about a stock fox with a stock aod going 13.8? They usually run 14.0-14.5 around here. I have never seen a stocker go that quick. I thinki can get my car into the high 14 sec territory with a good stall and a nice 60. Since it should be around a 15.60-15.70 right now with a slipping tranny. I think a new tranny and stall would propel me into a 14sec pass.

Anywho lol we ran this way off topic, I have had trouble with that latley. If the OP could chime in and tell us exactly what he will be using the car for that would be great. Wether he is off roading or running 24" wheels. Then maybe we can come to a better agreement.

[Mercracer]

as far as the converter hurting performance from a 40mph press, in my personal experiences, you are wrong. there is no other way to put it.I went from a 5spd to c4 with 3800stall. I had 2 friends what were extremely close in performance to measure before and after, as well as a stack of timeslips. testing was done out of the hole, 30mph press, 45mph press, 60mph press. the looser converter does not hurt performance; maybe in theory, but not in real world testing. the looser stall puts the motor in its powerband at all times. not a hard concept to grasp that when you wind the motor up it makes more power
.

We are not talking apples to apples. You have much more mods.... Your 2 friends likely did not hve the same combo. Their combo may have been less than ideal. "Performance" is relative unless you have a comparable combo

[jayh]

We are not talking apples to apples. You have much more mods.... Your 2 friends likely did not hve the same combo. Their combo may have been less than ideal. "Performance" is relative unless you have a comparable combo

ok Ill break this down for you and you can explain how its not "apples to apples"

car#1
87 mustang GT
308ci
stage 5 ported 289 heads milled to 48cc, E303 w/1.7's, holley syatemmax ][, longtubes, full exhaust
3.73 gear
5 spd, later c4 with 10" converter(3800)
1/8- 8.0@87 1/4- 12.5@1110 (12.4@109 with c4 1/8 unchanged)
3460 with driver

car #2
91 mustang GT
306ci
stage 2 ported edelbrock performer rpm heads, x303, holley systemax ][, longtubes, full exhaust
3.55 gear
5spd
1/8- 8.0@88 1/4- 12.5@110
3350 w/driver

car#3
85 mustang GT
stage 3 ported E7's, f303, performer rpm, 650dp, longtubes, full exhaust
3.73 gear
5spd
1/8- 8.0@87 1/4 12.5@110
3200 w/driver

all 3 cars ran door handle to door handle on the street and turned in identical timeslips. car #2 made 310rwhp on a dynojet, car #3 made 303rwhp, same dyno, car#1 never seen a dyno

how is this NOT an apples to apples comparison?





btw AODstangs 100%stock run low 15's here, with every bolton, low 14's

[1980c10]

What's the elevation at your local track jay? Just curious.

[jayh]

Im not sure to be honest, average DA is about 3000'(humidity is usually high)
so corrected those times are roughly 12.2@113
1/8mile was Lancaster, now called Dunntireracewaypark
1/4mile was NewYork International Raceway

not really setting the world on fire, but this was 10yrs ago, OTS letter cams, shifted at 6000-6200, longrunner/dual plane intakes, basic h/c/i 5.0 mustangs~ street cars. basically somewhat respectable, but not gonna win heads up class racing or anything like that. pretty much daily drivers that went to the strip for TnT's

[meanmercn]

ok this car isn't ever if ever see any track time. im building a car for show and jayh is right i will be running 255/30-26 tires that come out around 32". i know this isn't everybodys thing and i appreciate that cause everyones ideas are different. i want the car to be driveable cause i'd like to be able to drive it to and from shows. i live near greensboro nc and do a mix of city and highway driving so im trying to find a comfortable set up between the two. my younger brother has a 98 civillian crown vic with full 2.5" duals no crossover or headers and 3.73's no track lok with 305/30-26 tires on it 33.7" i believe and it drives very well no problems hittin the top speed governer and out running alot of cars on the highway and he drive it daily. i set my benchmark to that but i want to my merc to be a lil more sound i guess cause his transmission isn't happy at all its all stock.

[1980c10]

Well first off make sure you take some pics. Not my style I like big wheels just not that big. I think the biggest I would run on a box body would be 22's. But I can always appreciate a clean car.

I would still suggest 4.10 gears, with a 32'' tire in OD at 70mph you will only be turning 2000rpm.

For the carb try a 670cfm holley street avenger. Vacuum secondaries and electric choke. Its a nice street carb.

http://www.amazon.com/Holley-0-81670-4-Barrel-Secondary-Carburetor/dp/B000CMDUXK

This cam will put you right in your power band for highway cruising.

http://www.jegs.com/i/Comp-Cams/249/CL35-218-3/10002/-1?parentProductId=746636

Try out an eddy air gap intake with it.

http://www.jegs.com/i/Edelbrock/350/7581/10002/-1?parentProductId=746545

Find a set of gt40 heads and put some better springs on them with some 1.7 rr.

I still say 3k on the stall. You are going to have alot of mass to get moving with 26'' wheels. I am sure they are over 60lbs a piece. It will need all the help it can get.

That will make for a nice highway cruiser to take to shows, and still be able to do a little showing off it you need to.

Last but not least, make sure you do the big brake upgrade. For the same reason there is alot more rotational mass in a 26'' wheel then there is in a 15'' wheel, so your brakes are gonna have to work alot harder to stop the car.

[Pesty351]

If your going to run 26 inch wheels you might as well keep it stock.

[jayh]

all the track is is a stopwatch. tractionwise there is some stuff that will help ET at the track that doesnt apply on the street, but its a good tool to measure performance

most people who are looking for performance want the car to accelerate faster. even if they never go to the track, they do want to pull away from there buddies if they ever line up, whether its from a light, or cruising down the street side by side

generally speaking, what works on the street, works on the track, and vise versa

part of gear selection is first, what trageted rpm do you plan to spin the motor to/make peak power at? are you looking for absolute top end like a standing mile or faster acceleration, basically streetlight drag racing? how much cruise rpm are you willing to sacrifice?

32"tire will kill off some gear compared to a 27" tire
heres a calculator-

http://www.mustangworks.com/index.cfm/page_id/8

a trap speed of 110 @ 6000 on a 27" tire suggests a 4.30 gear
a trap speed of 110 @ 6000 on a 32" tire suggests a 4.56 gear

a mild 351 of this caliber is only gonna push a panther between 105-110 in the 1/4

I personally have no use to go 160mph, but that is personal preferance/goals

[meanmercn]

i have another box grand marq for a dd that'll stay pretty much factory stock atleast it'll look that way lol. im lookin at a power band in 1500-6000 range, which seems like a good streetable range to me. so im guessing the xe264 cam would fit better. Im doin the big brake upgrade right now as well as freshing up the front end suspension. the front upper a-frames and rear trailing arms will be replaced with http://universalcarlifts.com/popup_image.php?pID=42.