GOT A 351..stroke it? rod ratio q's

LX XLR8R · 10-22-2001, 10:12 AM

ok i got a 351 out of a 94 bronco..i plan on keeping the motor a roller moter for the time being..here is my proposed combo basically out of a MM&FF dyno pull test

393 coast high stroker kit, afr 185 heads, victor jr intake, speed demon 750 carb, comp cams XE274HR(.555/.565,224/232)..the compressino ratio will be 10.5:1 with the 64cc heads..this combo put out lil more than 500hp at the crank..
now i got questions..i only will bring this motor to about 6500 to prolong the life, what rod ratio do i want for longitivity and being able to rev it that high or higher safley(i know the hydrolic cam will hinder this)..the rod ratio of the 393 motor will be 1.59..they offer a 377 kit witch comes out to 1.655..they alos offer a more expensive 383 kit witch is 1.66..basically what is a # that i should at least get?and how much power can a 351 block handle?

------------------
1987 black notch(ex 4 banger)
DSS 306 w/ main support...Elderbrock 6028 heads..gt-40 intake..24# injectors...70 mm tb..77 pro-m...accel 300+..mac full legnth..tremec w/ pro5oh...full MAC exhaust,off road h-pipe,long tubes, catback...ron davis radiator..subframes, control arms...CFDF II..o yea holley FPR sucks..dont buy one..
AIM=onesillynotch

macx · 10-22-2001, 10:40 PM

Unless you're going for a really high rod/stroke ratio like a 351W with 6.58 rods to get a 1.88, which is a good torque motor but probably wouldn't match up with that potent of a 393 you're talking about, you probably want the bigger cubes of the 393. The small difference in rod/stroke with the 377 etc is too small to make up the diff in the cubes. The 351 block should handle that, but might be good insurance to use ARP studs etc. Keeping the r's around 6500 is a wise idea (stress on the lower end goes up WAY fast with higher revs), and should match the effective peaks of hp & torque for that cam with that many cubes. In fact, your torque peak will probably be around 4000+ and hp peak around 5000+. In fact, I think Ford uses a bigger Comp cam in their 393 crate motor. You probably also want to think about Eagle or other reasonably priced aftermarket rods. Using a dished piston, like JE's Yates style, will also yield more torque (keeps the combustion pressure more on the piston as opposed to the head/cyl wall surfaces as well as resisting detonation better). BTW check www.oemfordparts.com for a Ford stroker kit with hd truck rods, or crank by itself or whatever. for good discounts on ford parts check www.fordpartsnetwork.com

LX XLR8R · 10-23-2001, 08:29 AM

well i talked to coast high and the compression will be 11:1 with 64cc heads..he also said that they are seeing 100,000 miles on thier 408's and the 393 has a better ratio than that..he also said that the steet fighter kit is capable of 700hp so is suffecient for me!!!i might be swapping out my cam for the bigger XE282HR but i have to see..thanks guys..any info on anyone running one of these kits..
o BTW none of those kits have intersecting wrist pins and oil control rings

------------------
1987 black notch(ex 4 banger)
DSS 306 w/ main support...Elderbrock 6028 heads..gt-40 intake..24# injectors...70 mm tb..77 pro-m...accel 300+..mac full legnth..tremec w/ pro5oh...full MAC exhaust,off road h-pipe,long tubes, catback...ron davis radiator..subframes, control arms...CFDF II..o yea holley FPR sucks..dont buy one..
AIM=onesillynotch

MiracleMax · 10-23-2001, 07:53 PM

R/S ratios are for the most part academic in the realm of a street engine if cam and igniition timing are set-up for the particular R/S ratio.

[This message has been edited by MiracleMax (edited 10-23-2001).]

juiceman · 10-24-2001, 08:11 PM

rod ratio is not something you should be concerned with. it really doesnt make a difference. unless you plan on running pro stock or such. as for 500 hp from a stock motor, youre pushing it. it will handle it but not for long especially at 6500 rpm. 351's are not made for reving and dont last long when reved. i didnt know you wanted to go 10's you should have told me. if you want me to build you a 10 sec motor i can do that. and itll probably be cheaper that the 6000 or so youll spend on all that fancy stuff. let me know if you still want me to build that thing.

LX XLR8R · 10-25-2001, 08:58 AM

yea juice i still want you to build it..you havent been online in a while...i might have one of my buddies car just to rebuild also cuz its got a knock..anyhow yea i wanna go low 11's high 10's on motor..how should i do it? send me an email at notch4u@sprintpcs.com

------------------
1987 black notch(ex 4 banger)
DSS 306 w/ main support...Elderbrock 6028 heads..gt-40 intake..24# injectors...70 mm tb..77 pro-m...accel 300+..mac full legnth..tremec w/ pro5oh...full MAC exhaust,off road h-pipe,long tubes, catback...ron davis radiator..subframes, control arms...CFDF II..o yea holley FPR sucks..dont buy one..
AIM=onesillynotch

10-22-2001, 10:12 AM	#1
LX XLR8R Dirk Diggler Join Date: Feb 1999 Location: SLOATSBURG, NY Posts: 1,931	GOT A 351..stroke it? rod ratio q's ok i got a 351 out of a 94 bronco..i plan on keeping the motor a roller moter for the time being..here is my proposed combo basically out of a MM&FF dyno pull test 393 coast high stroker kit, afr 185 heads, victor jr intake, speed demon 750 carb, comp cams XE274HR(.555/.565,224/232)..the compressino ratio will be 10.5:1 with the 64cc heads..this combo put out lil more than 500hp at the crank.. now i got questions..i only will bring this motor to about 6500 to prolong the life, what rod ratio do i want for longitivity and being able to rev it that high or higher safley(i know the hydrolic cam will hinder this)..the rod ratio of the 393 motor will be 1.59..they offer a 377 kit witch comes out to 1.655..they alos offer a more expensive 383 kit witch is 1.66..basically what is a # that i should at least get?and how much power can a 351 block handle? ------------------ 1987 black notch(ex 4 banger) DSS 306 w/ main support...Elderbrock 6028 heads..gt-40 intake..24# injectors...70 mm tb..77 pro-m...accel 300+..mac full legnth..tremec w/ pro5oh...full MAC exhaust,off road h-pipe,long tubes, catback...ron davis radiator..subframes, control arms...CFDF II..o yea holley FPR sucks..dont buy one.. AIM=onesillynotch

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10-22-2001, 10:40 PM	#2
macx Registered Member Join Date: Oct 1999 Location: Gordonville MO USA Posts: 448	Unless you're going for a really high rod/stroke ratio like a 351W with 6.58 rods to get a 1.88, which is a good torque motor but probably wouldn't match up with that potent of a 393 you're talking about, you probably want the bigger cubes of the 393. The small difference in rod/stroke with the 377 etc is too small to make up the diff in the cubes. The 351 block should handle that, but might be good insurance to use ARP studs etc. Keeping the r's around 6500 is a wise idea (stress on the lower end goes up WAY fast with higher revs), and should match the effective peaks of hp & torque for that cam with that many cubes. In fact, your torque peak will probably be around 4000+ and hp peak around 5000+. In fact, I think Ford uses a bigger Comp cam in their 393 crate motor. You probably also want to think about Eagle or other reasonably priced aftermarket rods. Using a dished piston, like JE's Yates style, will also yield more torque (keeps the combustion pressure more on the piston as opposed to the head/cyl wall surfaces as well as resisting detonation better). BTW check www.oemfordparts.com for a Ford stroker kit with hd truck rods, or crank by itself or whatever. for good discounts on ford parts check www.fordpartsnetwork.com

10-23-2001, 08:29 AM	#3
LX XLR8R Dirk Diggler Join Date: Feb 1999 Location: SLOATSBURG, NY Posts: 1,931	well i talked to coast high and the compression will be 11:1 with 64cc heads..he also said that they are seeing 100,000 miles on thier 408's and the 393 has a better ratio than that..he also said that the steet fighter kit is capable of 700hp so is suffecient for me!!!i might be swapping out my cam for the bigger XE282HR but i have to see..thanks guys..any info on anyone running one of these kits.. o BTW none of those kits have intersecting wrist pins and oil control rings ------------------ 1987 black notch(ex 4 banger) DSS 306 w/ main support...Elderbrock 6028 heads..gt-40 intake..24# injectors...70 mm tb..77 pro-m...accel 300+..mac full legnth..tremec w/ pro5oh...full MAC exhaust,off road h-pipe,long tubes, catback...ron davis radiator..subframes, control arms...CFDF II..o yea holley FPR sucks..dont buy one.. AIM=onesillynotch

10-23-2001, 07:53 PM	#4
MiracleMax Registered Member Join Date: Apr 1999 Location: Hayes, Va, USA Posts: 798	R/S ratios are for the most part academic in the realm of a street engine if cam and igniition timing are set-up for the particular R/S ratio. [This message has been edited by MiracleMax (edited 10-23-2001).]

10-24-2001, 08:11 PM	#5
juiceman Registered Member Join Date: Jan 2001 Location: ny Posts: 197	rod ratio is not something you should be concerned with. it really doesnt make a difference. unless you plan on running pro stock or such. as for 500 hp from a stock motor, youre pushing it. it will handle it but not for long especially at 6500 rpm. 351's are not made for reving and dont last long when reved. i didnt know you wanted to go 10's you should have told me. if you want me to build you a 10 sec motor i can do that. and itll probably be cheaper that the 6000 or so youll spend on all that fancy stuff. let me know if you still want me to build that thing.

10-25-2001, 08:58 AM	#6
LX XLR8R Dirk Diggler Join Date: Feb 1999 Location: SLOATSBURG, NY Posts: 1,931	yea juice i still want you to build it..you havent been online in a while...i might have one of my buddies car just to rebuild also cuz its got a knock..anyhow yea i wanna go low 11's high 10's on motor..how should i do it? send me an email at notch4u@sprintpcs.com ------------------ 1987 black notch(ex 4 banger) DSS 306 w/ main support...Elderbrock 6028 heads..gt-40 intake..24# injectors...70 mm tb..77 pro-m...accel 300+..mac full legnth..tremec w/ pro5oh...full MAC exhaust,off road h-pipe,long tubes, catback...ron davis radiator..subframes, control arms...CFDF II..o yea holley FPR sucks..dont buy one.. AIM=onesillynotch