HP/TQ predictions...
08-12-2008, 10:18 PM
#1
HP/TQ predictions... I'm getting the car dyno tuned Friday and I'm curious to see what it makes. My current setup is:
-355ci LT1
-stock LT1 heads
(decked to 11.1 CR, 3 angle valve job w/ all new valves & 918 springs)
-CC503 camshaft
-double roller timing chain
-CSR electric water pump
-Scorpion 1.6 RR
-AC delete
-fully hand ported LT1 intake manifold
-Holley 58mm throttle body
-Jet Hot Long tubes
-Hooker ORY
-GMMG catback
-stock injectors
-MSD Billet Optispark
-Aluminum DS
-stock 3.42 rearend
What does everyone think? What's the predictions?
-355ci LT1
-stock LT1 heads
(decked to 11.1 CR, 3 angle valve job w/ all new valves & 918 springs)
-CC503 camshaft
-double roller timing chain
-CSR electric water pump
-Scorpion 1.6 RR
-AC delete
-fully hand ported LT1 intake manifold
-Holley 58mm throttle body
-Jet Hot Long tubes
-Hooker ORY
-GMMG catback
-stock injectors
-MSD Billet Optispark
-Aluminum DS
-stock 3.42 rearend
What does everyone think? What's the predictions?
08-13-2008, 12:17 AM
#2
TECH Fanatic
iTrader: (1)
Join Date: Aug 2005
Location: San Diego
Posts: 1,081
Likes: 0
Received 0 Likes
on
0 Posts
I'm fairly new to this guessing game and am not yet familiar with all the lt1 cams, as much as I see that one used, but I'm going to guess over 350 RWHP.
I'm thinking you'll be over 85% DC on your stock injectors, though.
I'm thinking you'll be over 85% DC on your stock injectors, though.
08-13-2008, 12:37 AM
#3
TECH Fanatic
iTrader: (6)
Join Date: Feb 2008
Location: Tucson, AZ
Posts: 1,714
Likes: 0
Received 0 Likes
on
0 Posts
You'll need new injectors. I'm doing a very similar set up and from what I've read you should be around 360RWHP.
If your looking to save money on injectors you can get them out of a Pontiac GTP and they flow at 34lbs and go for about $5 each. If you want more info on this, PM me.
If your looking to save money on injectors you can get them out of a Pontiac GTP and they flow at 34lbs and go for about $5 each. If you want more info on this, PM me.
08-13-2008, 01:15 AM
#5
TECH Fanatic
iTrader: (5)
Join Date: Mar 2004
Location: Melrose, MA
Posts: 1,196
Likes: 0
Received 0 Likes
on
0 Posts
Why, that would corner the market in injectors!
(And yes, you DEFINITELY need bigger injectors.....Might be able to get away with 30s but if it were me Id be picking up some 36s).
My Guess WITHOUT injectors is going to be 350-360rwhp
My Guess WITH injectors would be more in the 380rwhp range....Maybe 390rwhp because of the higher CR/ported heads.
Everyone take into account that he has a 355, which will make a difference especially with those heads/cam...
(And yes, you DEFINITELY need bigger injectors.....Might be able to get away with 30s but if it were me Id be picking up some 36s).
My Guess WITHOUT injectors is going to be 350-360rwhp
My Guess WITH injectors would be more in the 380rwhp range....Maybe 390rwhp because of the higher CR/ported heads.
Everyone take into account that he has a 355, which will make a difference especially with those heads/cam...
08-13-2008, 04:07 AM
#6
TECH Fanatic
iTrader: (6)
Join Date: Feb 2008
Location: Tucson, AZ
Posts: 1,714
Likes: 0
Received 0 Likes
on
0 Posts
I was weary to post this as it was not my find, but I'll just give credit where credit is most certainly due.
I think it ended up averaging 33.5lbs at stock LT1 Fuel pressure. I was able to get 6 of them at a GTP forum for about $20. Had to pay another $20 to get 2 more though. But $40 beats the hell out of $300 for a new set.
Originally Posted by mdenz3 of CZ28.com
My injector research part II
Okay, today the first set of 3800 series II S/C injectors showed up. The good news is they are the same length and have the same o-rings so they will hook right up. I have not checked to see if the clips will work properly with them yet. My flow testing, again at 16ms, 3000rpm, 43PSI, resulted in the fallowing:
Injector……..Flow in ml
1…………….265
2…………….260
3…………….260
4…………….265
5…………….255
6…………….255
Using the math in my previous post you’ll get the fallowing flow rates for them:
265 ml = 5.25 Gal / hr = 34.327 lbs / hr
260 ml = 5.15 Gal / hr = 33.680 lbs / hr
255 ml = 5.05 Gal / hr = 33.032 lbs / hr
As you can see these did vary slightly more from injector to injector, about 4% compared to the 2.5% observed with the LT1 injectors. However, seeing as these come in sets of six, I’ll be able to choose the best eight matching injectors to run.
Now to figure out how much horsepower these injectors can support. To do that we need to know about B.S.F.C. (Brake Specific Fuel Consumption). B.S.F.C. is the amount of fuel, in pounds, that the engine will use per hour, per horsepower it produces. The recommended levels of fuel consumption are; .45-.50 lbs per hr per hp for naturally aspirated engines, .55-.60 lbs per hr per hp for supercharged engines, and .60-.65 lbs per hr per hp for turbo charged engines. To determine what horsepower levels an injector will support use the fallowing formula:
injector size (in lbs / hr) X % duty cycle / B.S.F.C = Horse Power supported per injector
For this example:
34.327 X .80 / .50
27.4616 / .50
54.9232 hp per injector, or a 439 hp N/A V8
To determine what size fuel injectors your engine will need you would use the fallowing formula:
Horsepower X B.S.F.C / Number of injectors X Duty cycle ( 80% )
For example:
400 X .50 / 8 X .80
200 / 6.4
31.25 lbs / hr injectors
Okay, today the first set of 3800 series II S/C injectors showed up. The good news is they are the same length and have the same o-rings so they will hook right up. I have not checked to see if the clips will work properly with them yet. My flow testing, again at 16ms, 3000rpm, 43PSI, resulted in the fallowing:
Injector……..Flow in ml
1…………….265
2…………….260
3…………….260
4…………….265
5…………….255
6…………….255
Using the math in my previous post you’ll get the fallowing flow rates for them:
265 ml = 5.25 Gal / hr = 34.327 lbs / hr
260 ml = 5.15 Gal / hr = 33.680 lbs / hr
255 ml = 5.05 Gal / hr = 33.032 lbs / hr
As you can see these did vary slightly more from injector to injector, about 4% compared to the 2.5% observed with the LT1 injectors. However, seeing as these come in sets of six, I’ll be able to choose the best eight matching injectors to run.
Now to figure out how much horsepower these injectors can support. To do that we need to know about B.S.F.C. (Brake Specific Fuel Consumption). B.S.F.C. is the amount of fuel, in pounds, that the engine will use per hour, per horsepower it produces. The recommended levels of fuel consumption are; .45-.50 lbs per hr per hp for naturally aspirated engines, .55-.60 lbs per hr per hp for supercharged engines, and .60-.65 lbs per hr per hp for turbo charged engines. To determine what horsepower levels an injector will support use the fallowing formula:
injector size (in lbs / hr) X % duty cycle / B.S.F.C = Horse Power supported per injector
For this example:
34.327 X .80 / .50
27.4616 / .50
54.9232 hp per injector, or a 439 hp N/A V8
To determine what size fuel injectors your engine will need you would use the fallowing formula:
Horsepower X B.S.F.C / Number of injectors X Duty cycle ( 80% )
For example:
400 X .50 / 8 X .80
200 / 6.4
31.25 lbs / hr injectors
Last edited by Counted Out; 08-13-2008 at 05:56 AM.
Trending Topics
08-13-2008, 09:46 AM
#10
TECH Fanatic
iTrader: (5)
Join Date: Mar 2004
Location: Melrose, MA
Posts: 1,196
Likes: 0
Received 0 Likes
on
0 Posts
Mine was a complete guess, although its not completely impossible for him to make 370-380rwhp with that setup (ported heads, decent cam, higher CR, 355ci, ported intake, ect..). Just throwing a number up there, nothing scientific about it...
08-13-2008, 11:34 AM
#11
My heads are not ported. They have just been cleaned, decked and a 3 angle valve job with new valves to make sure they seal correctly. They are heads off of a 93' Firehawk but I doubt that makes any difference.
I figured I was going to have to up the injector size over stock as to I am going to be running a 115 shot here in a few months. Right now I just want to get the car running good without problems. Guess the next step is injectors...
I figured I was going to have to up the injector size over stock as to I am going to be running a 115 shot here in a few months. Right now I just want to get the car running good without problems. Guess the next step is injectors...
08-13-2008, 06:05 PM
#12
I will be happy for him if he proves me wrong and it makes 360 AND runs the numbers to back it up, but I wont assume that is the case like the rest of you.
08-13-2008, 07:11 PM
#16
TECH Fanatic
iTrader: (6)
Join Date: Feb 2008
Location: Tucson, AZ
Posts: 1,714
Likes: 0
Received 0 Likes
on
0 Posts
Will a larger throttle body really cause him to lose power though? Eventually he may need it and I don't think its hurting anything having it now.
And has far as the cam "not being a big number maker", the CC503 is often considered the biggest cam to put in a street car.
And has far as the cam "not being a big number maker", the CC503 is often considered the biggest cam to put in a street car.
08-13-2008, 08:01 PM
#17
Will a larger throttle body really cause him to lose power though? Eventually he may need it and I don't think its hurting anything having it now.
And has far as the cam "not being a big number maker", the CC503 is often considered the biggest cam to put in a street car.
And has far as the cam "not being a big number maker", the CC503 is often considered the biggest cam to put in a street car.
Also yea, the cc503 is regarded as perhaps the biggest to really go in a stock short block/headed setup because anything larger isn't a good idea rpm wise since the stock block doesn't really like to go past or much past 6300 or so. If not stock by all means go larger, if I had a worked block and ported stock heads I would have something along the lines of a gm847 but custom of course. Whoever said cc503 isn't a big number maker isn't right or wrong really, it makes good power and you cannot argue that. It makes more peak power than the Hot Cam, cc305, Crane 227 etc. but less peak than the cc306 and gm847. Peak numbers aren't everything anyways unless someone wants to be a dyno queen, its usable power that counts! But everyones ideal usable power range is different just depends on what the car is used for.
Assuming the quality is good with the work done to the heads/block I would like to say 350-360rwhp. I did 330rwhp through my automatic with the same cam and full exhaust and rockers so thats where I came up with your numbers. Good luck!
Last edited by StealthFormula; 08-13-2008 at 08:21 PM.
08-13-2008, 08:12 PM
#18
Staging Lane
iTrader: (5)
Join Date: Oct 2005
Location: Arkansas
Posts: 93
Likes: 0
Received 0 Likes
on
0 Posts
I'm getting the car dyno tuned Friday and I'm curious to see what it makes. My current setup is:
-355ci LT1
-stock LT1 heads
(decked to 11.1 CR, 3 angle valve job w/ all new valves & 918 springs)
-CC503 camshaft
-double roller timing chain
-CSR electric water pump
-Scorpion 1.6 RR
-AC delete
-fully hand ported LT1 intake manifold
-Holley 58mm throttle body
-Jet Hot Long tubes
-Hooker ORY
-GMMG catback
-stock injectors
-MSD Billet Optispark
-Aluminum DS
-stock 3.42 rearend
What does everyone think? What's the predictions?
-355ci LT1
-stock LT1 heads
(decked to 11.1 CR, 3 angle valve job w/ all new valves & 918 springs)
-CC503 camshaft
-double roller timing chain
-CSR electric water pump
-Scorpion 1.6 RR
-AC delete
-fully hand ported LT1 intake manifold
-Holley 58mm throttle body
-Jet Hot Long tubes
-Hooker ORY
-GMMG catback
-stock injectors
-MSD Billet Optispark
-Aluminum DS
-stock 3.42 rearend
What does everyone think? What's the predictions?
Last edited by nonosvt; 08-13-2008 at 08:33 PM.
