Advise on Ford 302- 331/347

[zarpoxx]

Many thanks to all for your choices,

I go by parts:

The compression of the engine is the origin, that is, 9.5 so I read that gave the Ford engines that year. The odometer marks only 650 miles, but it is not work so I have no idea how many miles the engine has (two year ago had the same miles...)

I do not have any restrictions on emissions or noise, so I have no problems in this regard with the law.

I would like to have a nasty idle sound, for me it is part of the special character of the cobra.

Maybe I did not express myself well, what I wanted to say is that although it is a car that is going to be used on the street (I speak of mountain passes and deserted roads) 100% of the time, I like to do a sporty driving, but not I'm looking for a car that gives the power at 7,000 rpm.

In fact, one of the thousands of things that has fallen in love with the Cobra is its torque at low turns (here in Europe a car with 5 liters of displacement is considered a HUGE engine, I no longer want to value what is thought of a motor Of 7 liters , so my priority is to not lose that good down torque.

That is to say, I would like a motor that goes down at least as it goes now (great for my taste), but it has the capacity to breathe up, since at present I notice that if I stretch it more than 5000 or 5500 rpm it faints (although it can Stretch it at 6.000 rpm I notice that it is very forced). In short, it is not that you want the power at 7,000 rpm (and less if that is going to make it down there is nothing) but have a real use margin up to about 7,000 rpm, although the pontencia delivered it to 6500 Rpm (I do not know if I explain myself).

Maybe bykins and moore_rb have explained better than me. I only want a engine that is capable to reach 7.000 rpm, not to give the peak power at this point.

Bwdz, thank you for the explanation, did not know those details of the old engines.

[olddog]

The factory ford 5.0 block is generally accepted to be at tad on the week side for high HP builds.

You can buy a Ford boss 302 block with a 4.125 bore. It is stronger too.

https://performanceparts.ford.com/part/M-6010-BOSS302

By the time you find a used block, clean it up, bore it, hone it, etc, you will likely have similar money in it.

[Dimis]

Originally Posted by zarpoxx

Many thanks to all for your choices,

I go by parts:

The compression of the engine is the origin, that is, 9.5 so I read that gave the Ford engines that year. The odometer marks only 650 miles, but it is not work so I have no idea how many miles the engine has (two year ago had the same miles...)

I do not have any restrictions on emissions or noise, so I have no problems in this regard with the law.

I would like to have a nasty idle sound, for me it is part of the special character of the cobra.

Maybe I did not express myself well, what I wanted to say is that although it is a car that is going to be used on the street (I speak of mountain passes and deserted roads) 100% of the time, I like to do a sporty driving, but not I'm looking for a car that gives the power at 7,000 rpm.

In fact, one of the thousands of things that has fallen in love with the Cobra is its torque at low turns (here in Europe a car with 5 liters of displacement is considered a HUGE engine, I no longer want to value what is thought of a motor Of 7 liters , so my priority is to not lose that good down torque.

That is to say, I would like a motor that goes down at least as it goes now (great for my taste), but it has the capacity to breathe up, since at present I notice that if I stretch it more than 5000 or 5500 rpm it faints (although it can Stretch it at 6.000 rpm I notice that it is very forced). In short, it is not that you want the power at 7,000 rpm (and less if that is going to make it down there is nothing) but have a real use margin up to about 7,000 rpm, although the pontencia delivered it to 6500 Rpm (I do not know if I explain myself).

Maybe bykins and moore_rb have explained better than me. I only want a engine that is capable to reach 7.000 rpm, not to give the peak power at this point.

Bwdz, thank you for the explanation, did not know those details of the old engines.

Dear Zarpoxx,

I think you have explained yourself very well.
...and the more I learn about your situation and the terrain you'll be driving in Spain, the more I think a rear end ratio change is your initial solution.

Generally speaking our American compadres are exposed more to interstate/hwy/freeway cruising, straight-line dragging and/or circle track work, rowing through the gears isn't necessarily their number one consideration.

If your driving spiritedly through this sort of terrain:



Then you would be better served changing the rear end to something between 3.73 or 4.11 to help launch you out of those corners, and climb to the next apex.



Enjoy

[1795]

Dimis,

I concur. 3:31 is awful steep for climbing hills, unless you want to keep the car in 2nd and 3rd gear all the time. A lower gear ratio would put you in the power band and help with acceleration out of the corners. While it hurts the top end speed, you will never notice it going on those kind of roads.

What you want to do is take a look at the car as a whole when considering what to do. It is difficult to end up with a quality product if you piecemeal parts together. Do not just focus on the engine, but the transmission, rear end and suspension as well. Figure out what would be too costly or difficult to replace, and then try to build the rest around what you are going to keep and make it functional for your environment. There is no perfect car, what you need to decide is what combination will work well for most of your driving. Keep asking questions and do your research. You will get it right in the end. Drive the hell out of the car now and see what you like and what could need improving.

[Dwight]

I build a 347 with 10.6 compression street motor

350 rear wheel tq at 2500 rpms

402 rwhp 416 tq all in by 5250

would pull to 7,000, one time only.

Comp cam 35-518-8 224-232 with 1.7 Scorpion roller rockers

Lifters good to 6800 but not every day on the race track

I used Keith Craft Brodix heads, loved those head. I gained 80 hp on the dyno with his heads.

That was a torque motor!

[moore_rb]

Originally Posted by Dimis

you would be better served changing the rear end to something between 3.73 or 4.11 to help launch you out of those corners, and climb to the next apex.

Originally Posted by 1795

3:31 is awful steep for climbing hills, unless you want to keep the car in 2nd and 3rd gear all the time. A lower gear ratio would put you in the power band and help with acceleration out of the corners.

My car will climb a 10% grade in 4th gear, at +3500 feet elevation, doing 65-75mph, without issues. It doesn't lug, and it feels strong.

However, you are correct that If I am running through the mountain curves in a more spirited manner, then 3rd gear makes both me, and the car, much happier...

The rear gearing has to be balanced to the transmission. With a Toploader (or a non-overdrive Richmond 5-speed), 3.31's or 3.42's are just about perfectly suited to the internal ratios in the transmission (again, JMHO).

With an overdrive 5 speed (TKO or T5)- you have to calculate the correct rear end ratio based on the specific ratios used for 1st and 5th gears in your particular gearbox (Especially with the T5's, because there are so many different T5 gear sets out there).

Zarpox says he has a WC- T5 with the 2.95 first gear, and the .73 overdrive... This is the exact same trans I had in my previous green car (which also had a 302 that ran out of breath early, and could barely turn 6000RPM).

I ran 3.73 rear gears in that car (with the same 295/50 rear tires) and the overdrive was perfect, but 1st gear was REALLY short- I had to shift almost immediately (at about 30mph) under WOT acceleration. I always felt like 3.55's (or possibly 3.42's) would have probably been better choices for that engine and transmission combo.

This might be why Zarpox wants a higher revving engine, because I felt the exact same way with my green car - 1st gear acted like a 60 foot gear in a drag car- I had to upshift within 2 seconds whenever I launched that car hard.

If I had been able to make power up in the same 6000-6500 range like I can with my current car, then I would have been able to hold 1st gear longer, and the 3.73's would have been a better gearing combination for that car.

Zarpox- Here's another point for you to consider. If you are REALLY thinking about upgrading to a 500HP stroker for your car someday - An engine that powerful will be right on the upper limits of what your T5 transmission can handle, so you might want to consider adding the cost of a transmission change to your stroker plans, as well... Just more opinions

[1795]

Originally Posted by moore_rb

My car will climb a 10% grade in 4th gear, at +3500 feet elevation, doing 65-75mph, without issues. It doesn't lug, and it feels strong.

However, you are correct that If I am running through the mountain curves in a more spirited manner, then 3rd gear makes both me, and the car, much happier...

The rear gearing has to be balanced to the transmission. With a Toploader (or a non-overdrive Richmond 5-speed), 3.31's or 3.42's are just about perfectly suited to the internal ratios in the transmission (again, JMHO).

With an overdrive 5 speed (TKO or T5)- you have to calculate the correct rear end ratio based on the specific ratios used for 1st and 5th gears in your particular gearbox (Especially with the T5's, because there are so many different T5 gear sets out there).

Zarpox says he has a WC- T5 with the 2.95 first gear, and the .73 overdrive... This is the exact same trans I had in my previous green car (which also had a 302 that ran out of breath early, and could barely turn 6000RPM).

I ran 3.73 rear gears in that car (with the same 295/50 rear tires) and the overdrive was perfect, but 1st gear was REALLY short- I had to shift almost immediately (at about 30mph) under WOT acceleration. I always felt like 3.55's (or possibly 3.42's) would have probably been better choices for that engine and transmission combo.

I
I concur regarding the rear-end ratio. I had a top loader with a 3:54 rear end and I thought that it was the perfect combination. Engines are much happier when they are running in the middle of their power band, then when they are at the bottom of it.

Good point about being careful that he is not running an engine at the upper end of the power rating of the transmission. It eventually will catch up with you if components are run at the maximum of their capability.

[Kit Coyle]

I agree with Robert Moore. I have a 1970 BOSS 302 engine updated with
a solid roller cam good for around 400 hp. The rear is 3:31 and the Tremec
TKO has a 2:95 first gear which feels a bit short. If I went any lower in the
rear first gear would be a pain to use. The little Cleveland will pull past
7000rpm easily but the cam puts my peak hp at about 6500 and peak torque
at 4100rpm. On the freeway in 5th gear I see about 2200rpm at 70mph. The
car feels happy at slow speeds around town and never bulks. It feels like
a 4 speed toploader with over drive...which it essentially is! Whats not to like?

[cwhoofgatorr]

WELL I'll say this... Lance built my current engine and it a beast as far as I am concerned. 331, AFR 165 heads, Ford X cam, RPM air gap intake. 3:55 gears and I can't mat it any gear under forth. OH by the way Holley Terminator EFI and love it. I can run the mountains, flat land and just cruise. Could not be happier cars really gets with it and will spin the tires at will.. So far with 400 miles on the engine, averaging 19 MPG and that's getting on with it: Car pulls right to 6500 strong and I can't see any need for more power on a street car. If I remember right it's 10.1 Comp. JMHO. 3DSMILE: