Motors mods to increase low end torque

Cajun93

New Member
Jun 27, 2005
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South Louisiana
I come from a line a big block mopars (383s and 440s) so I'm partial to low end torque. My newly acquire hatch has pretty decent low end torque, I'm very impressed for its displacement.

I've been reading these forums for months on end without posting too much. Time after time I read about upgrades such as heads, intake, cam, etc increasing the top end performance but not low end. I have seen many guys opt for the stock cam to keep that low end grunt.

I do know that the twin screw blowers will increase low end torque. Are there any other H/C/I's or other mods I can do (besides a 351w) that will increase the low end torque from the moment you hit the pedal? I'd like around 400fwtq and a solid 12.8 - 13.0 sec car.

Gears will be in place soon, but I know shifting gets kinding hairy with 3.73's and a KB. :nice:

Thanks for the help- have a good 'un
 
For starters, some long tube headers, matching H-pipe and a cat-back exhaust.

Basically all the standard bolt ons. Then have you stock heads / intake ported that should put you above the 320 RWT.

You could go custom cam that would help a little also
 
Cajun93 said:
I come from a line a big block mopars (383s and 440s) so I'm partial to low end torque. My newly acquire hatch has pretty decent low end torque, I'm very impressed for its displacement.

I've been reading these forums for months on end without posting too much. Time after time I read about upgrades such as heads, intake, cam, etc increasing the top end performance but not low end. I have seen many guys opt for the stock cam to keep that low end grunt.

I do know that the twin screw blowers will increase low end torque. Are there any other H/C/I's or other mods I can do (besides a 351w) that will increase the low end torque from the moment you hit the pedal? I'd like around 400fwtq and a solid 12.8 - 13.0 sec car.

Gears will be in place soon, but I know shifting gets kinding hairy with 3.73's and a KB. :nice:

Thanks for the help- have a good 'un

Besides a twin screw blower the only other way to significantly add low end torque is to add cubic inches. You are limited to about 347 or so inches with a factory block. And the factory block isn't exactly known for its strength once blowers are added to the mix.

If you want to stay "302" you can get a Dart or World Products engine block with 4.125" bore and they support up to about 380 inches in the 302 size package.

You can get 400 fwft-lbs prety easy, but that will happen up in the 3800+ range. That's not low end in my book.
 
there are some aftermarket cams that will increase your off idle torq, i think crower makes some really good ones...

a KB will def give you the off idle torq you're seeking. but to get a 302 into the torq range you're "used to" then your gonna be praying for awhile, comparing a big block Chrysler to a sb Ford is apples and oranges...

400 rwt for a 302 is usually accompanied by about 425+hp...and that torq number is usually at a higher rpm than what most people would consider "low end"

but, the KB would work quite well for you...it won't give you that 383 or 440 pull, but it'll help out alot...and like tjm73 said, pushing high numbers out of a factory block is kinda risky-there's several people on here that have made boat achors and door stops from their previous build ups...

otherwise, drop your greenbacks on a 351 based stroker, and have fun...
 
Cajun93 said:
... I'd like around 400fwtq and a solid 12.8 - 13.0 sec car...


if you get 400rwt out of your 302, more than likely, you'll be pulling alot quicker times than that, more like 12.0-12.4...provided you can get it all to the ground. putting a 5.0 into the high 12's is not a hard task these days...slicks, and a typical assortment of bolt ons will take care of that one in a hurry!


edit: you might wanna stiffen the chassis, and beef up the suspension before you go making those numbers though, our beloved 'stangs are not very well known for great structural integrity...even those little mods, like subframes, control arms, and such will help your times a little...

good luck!
 
txstang84 said:
tru to a certain extent, but a 351 based engine will fit better into a fox body and has more parts availability for that application since it's such a common swap.

Factory 351W blocks can support up to 418 inches with nothing more than a .030" overbore and a 4.10 stroke crank. Clearence the bottom of the cylinder bores and you are golden.

With a 4.17" stroke you can get 425 inches, but may need a small base circle cam to clear the counter weights of the crank.

My brother is just finishing a 418W Ranger project. It's sick I got a couple vids, but no place to host them yet.
 
Very informative replies...
I don't plan on upgrading the block to a 351w until the stock 5L is done for. I plan on trying to get the most I can outta this one.

I wanted some opinions on what I can do with the stock long block. I just want power at 2k rpm and up.

My plans include ( in this order ):

Tokicos struts and shocks (car is dropped 1.5in around & is very rough)
C/C plates
subframes
DCC 18in kit (elec. fan)
155 fuel pump
1.5L KB
custom tune (SCT)
73 CL maf with 24lb inj
65mm tb (accufab)

How would this work for torque improvements?
Extrude ported lower GT-40 intake
Extrude ported stock heads

Thanks for the replies, keep 'em coming
 
For low end keep the factory headers and h-pipe on till you get to 260-270HP..Its the best set up for low end.I took off my headers first and noticed a big drop in low end.Then I replaced the h-pipe,same thing so I put it back on,and it felt better.I had the stock intake ported out along with some head work on the stock heads.Theres 2 guys in here that do it.T-Moss does the intake and the heads are done by Thumper 460..The heads go for 595.00,ported polished 5 angle valve job,for HD springs its a 100 more..T-Moss does the intake for 130 or 150 I forget..Lot-sa low end here!!Add 1.7 rockers and it picks up your mid range and a little up top.
 
I, myself, started with classic cars and I understand the desire to have a mustang with the same type of low end grunt as an old school big block but there is something that you need to consider. A 5.0 is among the hardest leaving cars there is. Not many cars launch like a mustang on slicks. A stock mustang with nothing but slicks and 4.10's will leave pretty much any mopar with a reasonable 383 or 440 in the dust for the first 60ft. Isn't that enough? How much more low end do you need? A Mustang is a sports car not a dump truck.
 
skip the cam.. unless you get a custom or a mild cam. The stock cam would probably keep the most down low power and torque, unless you get something custom.. which is going to be worth it in my opinion if you are trying to seriously meet a certain goal. Porting the stock heads, eh...might as well pick up those gt40Y on sale.. or go with a gt40p longblock from a yard and take the heads, intake, and tb from it.. sell the rest. Typically the GT40series equipment makes the most power on the low end of our rpm band. But is usually outpowered after 4k rpms buy the newer technology.

If you do alittle digging there is a hot rod magazine or 5.0 magazine build up where they take a 5.0 stock block with a stock crank.. and I believe a stock cam.. and go carb with it..ends up pushing 400hp out. They go with an AFR 165cc, stealth intake (i think), and some carb.. it might be worth your time to check around for it.. do a search on this site. I have efi, but have kept that page it the back of my mind as to the route I would go with carb if I wanted to max out a 5liter next go around.

Otherwise a gt40series setup with a roots type blower is probably going to be the way I would go to keep the most power in a lower rpm band, keeping the stock cam.
 
get the usual bolt on that increase power universally, reather than just on top end. A/C and smog delete, underdrives, etc

Keep the stock cam, you could try thumper heads, he ports his head with low end torque and instant throttle response in mind. And if you have a blower your set.

and for gears if your wanting PULL get some like 4.30s or real steep gears like that.
 
I'd go with 4.10's, cobra intake, gt40 heads, and drag radials for low end grunt.





I too come from a Mopar background. Lets just say my Mustang isn't even in the same league as my 68 440 dart. lol