351w or 347 stroker? which is better? - Page 3

sn95gt19 · 12-20-2002, 05:24 PM

ok hopefully i dont grenade the darn thing, it will mostly be just for street racing. so it shouldnt see more than 20 passes this year, at the end of the year im going to buy a dart block, and hopefully then it will take whatever i throw at it.

82 GT · 12-20-2002, 11:18 PM

Quote:

Originally posted by 2FastLX

Another issue I haven't seen anyone bring up (or I missed it) is the fact that the 351W block weighs something like 50lbs heavier than a 5.0 block (correct me if I'm wrong please). I'm not up on how much horsepower 50lbs of weight added to your car is comparable to, but you get the idea.

Every 100lb you take off is worth about a tenth in the 1/4 mile.
So you are talking only about about a .05 difference in E.T

ultraflo · 12-20-2002, 11:25 PM

Quote:

Originally posted by sn95gt19
ok hopefully i dont grenade the darn thing, it will mostly be just for street racing. so it shouldnt see more than 20 passes this year, at the end of the year im going to buy a dart block, and hopefully then it will take whatever i throw at it.

How many 1/4 mi. races will you do on the street? lol

...it all adds up, pretty quick!

Have you considered going with a smaller nitrous kit, maybe a single nozzle before the throttle body via NX, or even one of their new EFI plates that sandwich between the upper and lower intakes? ...the 300hp fogger setup would be a bit much, IMO.

-Ryan

sn95gt19 · 12-20-2002, 11:41 PM

could i spray 250 through a single fogger nozzle (wet kit) also how would that work do i just put a t before my fuel rails (i have an aeromotive setup) and run a gas line straight to the selenoid? i dont see how the nozzle would see enough fuel pressure to evenly distribute the nitrous and gas. the plate's for the efi systems are rediculously priced ($500+) so i dont want to do that, (i havent seen one for the victor efi intake yet). if i could run 250 through a single fogger nozzle i will do that.

the reason i want to spray so much is because i only have 8.5:1 compression, cause as soon as i can afford a precision ball bearing t76 turbo, im going to pick one of those up.

ultraflo · 12-20-2002, 11:58 PM

I sprayed 200hp through a single nozzle before the t.b. on my old combo this year, and the kit (NX EFI Race 20113) is adjustable in 100-150-200-250hp increments.

Also, NX makes a plate for the Victor 5.0 intake, as I will be stepping up to one in the future.

I'm going to start with the kit I already have once I get the new motor together, and add the plate later to make a two stage system.

As for fuel supply, I went off one side of the Paxton universal EFI regulator right to the solenoid. I run a line from the pump to a -8 NOS Y-fitting with two -8's to the rails. From the rails, two more -8 lines to another NOS Y-fitting, into one -8 line that goes to one side of the regulator, so I had the other side blocked off until the nitrous system was hooked up.

Ron1 · 12-21-2002, 12:41 AM

I picked this up on one of the other sites...maybe even here...

Originally posted by George Klass, CHP
"This rod/stroke ratio stuff is really not that big a deal for high end street racer type engines. How many of you older guys remember the old Ford 292 inch Y-Block engine? Generally considered a piece of crap; not much performance and not a very long lasting beast, either. Rod/stroke ratio? 1.91:1. Here are a few engines with their rod/stroke ratios: 454 Chevy - 1.53:1, 455 Pontiac - 1.58:1, 428 Ford Cobra Jet - 1.63:1, Ford SB 331 Stroker - 1.60:1, Ford SB 347 Stroker - 1.58:1, etc. The most important rod/stroke ratio to be concerned with for most street/strip racers is 8:1. Eight rods to one crank. As far as displacement is concerned, here is something to contemplate. NHRA penalizes displacement in all Comp Eliminator classes (weight to cubic inches). Now, why do you think that is? If bigger inch engines didn't have more HP potential, somebody needs to tell NHRA. There is nothing wrong with a 331 OR a 347. Take your pick. But don't get stuck with all this "theory" (side loads, rod/stroke, rod angles, etc.)"

(Quote)
Originally posted by George Klass
What follows is not an opinion, however. A CHP 347 Street Fighter will last as long or longer than a 331 or a 302. This is because of the exclusive oil control feature (discussed elsewhere on this board). Does anyone really think that a 260 or 289 will last longer than a 302?

(Quote)
Originally posted by George Klass
I have read all of the interesting and logical (and not so logical) reasons for choosing a 331 over a 347, and everyone of those reasons could apply to choosing a 289 over a 302. Which would you choose?

Just FYI

Ron

ultraflo · 12-21-2002, 12:47 AM

Thanks Ron, I had read that awhile back on Hardcore50.com

Quote:

The most important rod/stroke ratio to be concerned with for most street/strip racers is 8:1. Eight rods to one crank.

The reason I remember where I read that info is because those two sentences stuck with me, as I nearly fell out of my chair after reading that, lol, thinking to myself "Oh, so very true!"

sn95gt19 · 12-21-2002, 01:05 AM

just curious what selenoids they were, or equal to (nos) cheater, pro shot????also what jet sizes did you use, to get 100-200-250

Ron1 · 12-21-2002, 01:28 AM

I have noticed that you keep coming back to your compression ratio. As long as you use the right fuels it should never be a concern. I run 12.4 C/R so far only a 150 horse shot, but everything is geared to run 250 HP (If it will hook). As long as I have the right fuel, VP C16 in this case, I have no worries. C/R should not be calculated into the size of the shot. I would look at the cam...wider LSA, and a a bit more duration on the exhaust.

Ron

ultraflo · 12-21-2002, 01:40 AM

Unless you use an NX shark nozzle, the jetting would be different with a brand X nozzle... I have my jets out in the garage, and can post the jetting for each shot in the AM if you like.

As for solenoids... NX uses large solenoids in their kits. Go to www.nitrousexpress.com and have a look around to get an idea what I'm talking about.

If you are going to run NOS solenoids and nozzle, you'd be best off to get jetting specs from NOS. I wouldn't recommend using the jetting specs for an NX system, or any other brand system for that matter, as all manufacturers do not use identical jetting patterns for their hp ratings with various kits. I noticed that when I installed a NitrousWorks EFI t.b. plate on a buddy's '93 Cobra a few months ago.

ultraflo · 12-21-2002, 02:08 AM

here's a pic I dug up to give you an idea on the size of the solenoids...

sn95gt19 · 12-21-2002, 12:05 PM

ron1, the reason that i keep coming back to my compression ratio is that: ITS SAFER TO SPRAY 300 ON A 8.5:1 THAN IT IS ON A 12.5:1 CAR RIGHT. since the spray is only craming the chamber with oxygen when ignited, its acting just like a blower, so the lower the compression the more spray friendly it is RIGHT?

82 GT · 12-21-2002, 12:20 PM

The less volume efficient an engine is, the more effect NO2 will have on it.
IMO, I would say it's better to have a lower compression ratio than a higher one if using N02.

ultraflo · 12-21-2002, 01:09 PM

you mean N2O right?

I would say that spraying 300hp isn't any 'safer' with 8.5:1 compression than it is with, say, 16:1 if the tune and fuel octane aren't right... you can obviously make more power, and get a more efficient burn with higher compression, thus it is more desirable to run more compression with nitrous. Eric4Nitrous, as well as Bill Glidden, who did Eric's motor, both run around 16:1 and spray a WHOLE lot more than 300hp.

It's all in the tune when we're talking 'safe', because, face it, with nitrous you are eventually going to hurt a piston or have some sort of backfire, that's what finding the right tune is all about. Learn from your mistakes, take good notes, and progress from there.

Nitrous likes compression...

Ron1 · 12-21-2002, 02:07 PM

That's the answer. Could not agree more.

Thanks Ultraflo..

Ron

sn95gt19 · 12-21-2002, 06:52 PM

so ill be good until i get the turbo, thanks for the input guys. i sprayed 200 on my stock motor and eventually floated some valves and blew it up.

12-20-2002, 05:24 PM	#41
sn95gt19 motors done......woohooo Join Date: Mar 2002 Posts: 799	ok hopefully i dont grenade the darn thing, it will mostly be just for street racing. so it shouldnt see more than 20 passes this year, at the end of the year im going to buy a dart block, and hopefully then it will take whatever i throw at it. __________________ 95gt lazer red (98 cobra clone) Rice Haters Club Member #116

12-20-2002, 11:41 PM	#44
sn95gt19 motors done......woohooo Join Date: Mar 2002 Posts: 799	could i spray 250 through a single fogger nozzle (wet kit) also how would that work do i just put a t before my fuel rails (i have an aeromotive setup) and run a gas line straight to the selenoid? i dont see how the nozzle would see enough fuel pressure to evenly distribute the nitrous and gas. the plate's for the efi systems are rediculously priced ($500+) so i dont want to do that, (i havent seen one for the victor efi intake yet). if i could run 250 through a single fogger nozzle i will do that. the reason i want to spray so much is because i only have 8.5:1 compression, cause as soon as i can afford a precision ball bearing t76 turbo, im going to pick one of those up. __________________ 95gt lazer red (98 cobra clone) Rice Haters Club Member #116

12-20-2002, 11:58 PM	#45
ultraflo NX dealer-man Join Date: Sep 1998 Location: Peoria, Illinois Posts: 977	I sprayed 200hp through a single nozzle before the t.b. on my old combo this year, and the kit (NX EFI Race 20113) is adjustable in 100-150-200-250hp increments. Also, NX makes a plate for the Victor 5.0 intake, as I will be stepping up to one in the future. I'm going to start with the kit I already have once I get the new motor together, and add the plate later to make a two stage system. As for fuel supply, I went off one side of the Paxton universal EFI regulator right to the solenoid. I run a line from the pump to a -8 NOS Y-fitting with two -8's to the rails. From the rails, two more -8 lines to another NOS Y-fitting, into one -8 line that goes to one side of the regulator, so I had the other side blocked off until the nitrous system was hooked up. __________________ RLS Racing! 93 LX 9.20 @ 147mph 03 Mach 1 12.39 @ 116mph

12-21-2002, 01:05 AM	#48
sn95gt19 motors done......woohooo Join Date: Mar 2002 Posts: 799	just curious what selenoids they were, or equal to (nos) cheater, pro shot????also what jet sizes did you use, to get 100-200-250 __________________ 95gt lazer red (98 cobra clone) Rice Haters Club Member #116

12-21-2002, 01:40 AM	#50
ultraflo NX dealer-man Join Date: Sep 1998 Location: Peoria, Illinois Posts: 977	Unless you use an NX shark nozzle, the jetting would be different with a brand X nozzle... I have my jets out in the garage, and can post the jetting for each shot in the AM if you like. As for solenoids... NX uses large solenoids in their kits. Go to www.nitrousexpress.com and have a look around to get an idea what I'm talking about. If you are going to run NOS solenoids and nozzle, you'd be best off to get jetting specs from NOS. I wouldn't recommend using the jetting specs for an NX system, or any other brand system for that matter, as all manufacturers do not use identical jetting patterns for their hp ratings with various kits. I noticed that when I installed a NitrousWorks EFI t.b. plate on a buddy's '93 Cobra a few months ago. __________________ RLS Racing! 93 LX 9.20 @ 147mph 03 Mach 1 12.39 @ 116mph

12-21-2002, 12:41 AM	#46
Ron1 Registered Member Join Date: Sep 1999 Location: Vancouver, WA USA Posts: 439	I picked this up on one of the other sites...maybe even here... Originally posted by George Klass, CHP "This rod/stroke ratio stuff is really not that big a deal for high end street racer type engines. How many of you older guys remember the old Ford 292 inch Y-Block engine? Generally considered a piece of crap; not much performance and not a very long lasting beast, either. Rod/stroke ratio? 1.91:1. Here are a few engines with their rod/stroke ratios: 454 Chevy - 1.53:1, 455 Pontiac - 1.58:1, 428 Ford Cobra Jet - 1.63:1, Ford SB 331 Stroker - 1.60:1, Ford SB 347 Stroker - 1.58:1, etc. The most important rod/stroke ratio to be concerned with for most street/strip racers is 8:1. Eight rods to one crank. As far as displacement is concerned, here is something to contemplate. NHRA penalizes displacement in all Comp Eliminator classes (weight to cubic inches). Now, why do you think that is? If bigger inch engines didn't have more HP potential, somebody needs to tell NHRA. There is nothing wrong with a 331 OR a 347. Take your pick. But don't get stuck with all this "theory" (side loads, rod/stroke, rod angles, etc.)" (Quote) Originally posted by George Klass What follows is not an opinion, however. A CHP 347 Street Fighter will last as long or longer than a 331 or a 302. This is because of the exclusive oil control feature (discussed elsewhere on this board). Does anyone really think that a 260 or 289 will last longer than a 302? (Quote) Originally posted by George Klass I have read all of the interesting and logical (and not so logical) reasons for choosing a 331 over a 347, and everyone of those reasons could apply to choosing a 289 over a 302. Which would you choose? Just FYI Ron

12-21-2002, 01:28 AM	#49
Ron1 Registered Member Join Date: Sep 1999 Location: Vancouver, WA USA Posts: 439	I have noticed that you keep coming back to your compression ratio. As long as you use the right fuels it should never be a concern. I run 12.4 C/R so far only a 150 horse shot, but everything is geared to run 250 HP (If it will hook). As long as I have the right fuel, VP C16 in this case, I have no worries. C/R should not be calculated into the size of the shot. I would look at the cam...wider LSA, and a a bit more duration on the exhaust. Ron

12-21-2002, 02:08 AM	#51
ultraflo NX dealer-man Join Date: Sep 1998 Location: Peoria, Illinois Posts: 977	here's a pic I dug up to give you an idea on the size of the solenoids... __________________ RLS Racing! 93 LX 9.20 @ 147mph 03 Mach 1 12.39 @ 116mph

12-21-2002, 12:05 PM	#52
sn95gt19 motors done......woohooo Join Date: Mar 2002 Posts: 799	ron1, the reason that i keep coming back to my compression ratio is that: ITS SAFER TO SPRAY 300 ON A 8.5:1 THAN IT IS ON A 12.5:1 CAR RIGHT. since the spray is only craming the chamber with oxygen when ignited, its acting just like a blower, so the lower the compression the more spray friendly it is RIGHT? __________________ 95gt lazer red (98 cobra clone) Rice Haters Club Member #116

12-21-2002, 12:20 PM	#53
82 GT Import Slayer Join Date: May 1999 Posts: 2,241	The less volume efficient an engine is, the more effect NO2 will have on it. IMO, I would say it's better to have a lower compression ratio than a higher one if using N02. __________________ '82 GT 351W (.060)Comp Cams 274* Extreme Energy cam, ported & polished heads w/ 1.94/1.60 valves 10.3:1 flat top pistons,stealth intake, Mallory dizzy,Holley 750dp carb, BBK shorties,Flowmaster exhaust,C-4 with 3700 stall converter, B&M pro shifter,8.8 rear, 4:10's, subframes, electric fan, powermaster alternator, 4 core radiator.

12-21-2002, 01:09 PM	#54
ultraflo NX dealer-man Join Date: Sep 1998 Location: Peoria, Illinois Posts: 977	you mean N2O right? I would say that spraying 300hp isn't any 'safer' with 8.5:1 compression than it is with, say, 16:1 if the tune and fuel octane aren't right... you can obviously make more power, and get a more efficient burn with higher compression, thus it is more desirable to run more compression with nitrous. Eric4Nitrous, as well as Bill Glidden, who did Eric's motor, both run around 16:1 and spray a WHOLE lot more than 300hp. It's all in the tune when we're talking 'safe', because, face it, with nitrous you are eventually going to hurt a piston or have some sort of backfire, that's what finding the right tune is all about. Learn from your mistakes, take good notes, and progress from there. Nitrous likes compression... __________________ RLS Racing! 93 LX 9.20 @ 147mph 03 Mach 1 12.39 @ 116mph

12-21-2002, 02:07 PM	#55
Ron1 Registered Member Join Date: Sep 1999 Location: Vancouver, WA USA Posts: 439	That's the answer. Could not agree more. Thanks Ultraflo.. Ron

12-21-2002, 06:52 PM	#56
sn95gt19 motors done......woohooo Join Date: Mar 2002 Posts: 799	so ill be good until i get the turbo, thanks for the input guys. i sprayed 200 on my stock motor and eventually floated some valves and blew it up. __________________ 95gt lazer red (98 cobra clone) Rice Haters Club Member #116

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
351W EFI in a Fox?	Big-T	Windsor Power	4	12-02-2002 09:43 AM
stroker kit for 351W	79coupe	Windsor Power	1	09-30-2002 10:19 PM
351W Stroker ?	tmmygnn	Windsor Power	11	11-01-2001 07:32 PM
Supercharger or stroker for a 351W??	Stang_ROTY	Windsor Power	2	03-12-2001 03:54 AM
HP #'s from a built 351W versus FMS 351 versus stroker	stroker393	Windsor Power	0	03-09-2001 10:24 AM