Hi guys
I have just finished my new engine and have had in dynoed.
It produced 613 hp @ 6800 rpm and 495 ft/lb at 6150.
I was hoping for a bit more than i got, somewhere up around the 630 -650 hp.
Can you guys have a look at my combo and see if you think I havent matched things correctly or if you see that i could change something
383 cubic inch Holden V8
3.75 billet crank
5.7 Lunati pro billet rods
CP Flat tops
The pistons have a zero deck height.
Solid roller cam with 272 int and 282 exh @50 and .708 int and .691 exh lift and on 112 LC ( went 112 so i could put lots of nitrous in)
Head are Yella Terra Alloys with 2.05 int and 1.65 exh, dual isky gold 1.55 springs.
Harrop single plane manifold
Dominator Carb adaptor, 1 inch nitrous plate and a 1 inch HVH Super sucker.
1050 Holley dominator (out of the box)
MSD Digital 6 ignition system.
4 into one pipes with 1.73 inch diameter and a 3 inch collector
We jetted the carb to 84 for the pri and secs and blocked of the intermediate circuit in the metering blocks for both the front and rear.
Set the timing to 30 degrees and gapped the plugs to .034 thou.
Can you guys see anything that I have done wrong. I was thinking that maybe i have to much stuff under the carb.
Thanks Trev
ENGINE COMBINATION
Moderator: Team
Trev,
my question to you is this. Do you plan as racing this setup as a nitrous engine? or a naturally aspiratied engine w/nitrous added?
YOu might have slightly to much carb. try 2 more degrees of timing, w/a slighty wider spark plug gap (.040) . How much air are your heads moving?(especially on the exhaust side do to future nitrous use)?
my question to you is this. Do you plan as racing this setup as a nitrous engine? or a naturally aspiratied engine w/nitrous added?
YOu might have slightly to much carb. try 2 more degrees of timing, w/a slighty wider spark plug gap (.040) . How much air are your heads moving?(especially on the exhaust side do to future nitrous use)?
You should have around 12.5:1 , all depending on what the final chamber volume is, although most of the 383 Holden engines I have seen with Flat tops finshed up around 12-13:1
Holden engines don't like alot of ignition timing, I don't recall seeing a Late style YT headed engine run anymore than 30 degrees total. I remember an engine that was dynoed at my friends shop that was a Flat tappet 383 with YT heads, made 627hp on 100 octane with 28 total, and 613HP on Pump with 22 Total.
There are too many unknowns to know if there is more in your combo
AL...
Holden engines don't like alot of ignition timing, I don't recall seeing a Late style YT headed engine run anymore than 30 degrees total. I remember an engine that was dynoed at my friends shop that was a Flat tappet 383 with YT heads, made 627hp on 100 octane with 28 total, and 613HP on Pump with 22 Total.
There are too many unknowns to know if there is more in your combo
AL...
383
LA360
Can you give us any details on that flat tappet 383? Was it run in a car and if so, how'd she go?
Trev
Sounds like that combination should have made a bit more but i don't know about those correction factors you mentioned. What car is it going in? Get it out there and give it a go.
Think a 950HP might have been a better choice than the dominator. And there is a lot under that carb.
Do you think those pipes could be a touch on the small side?
Cheers
Fatty
Can you give us any details on that flat tappet 383? Was it run in a car and if so, how'd she go?
Trev
Sounds like that combination should have made a bit more but i don't know about those correction factors you mentioned. What car is it going in? Get it out there and give it a go.
Think a 950HP might have been a better choice than the dominator. And there is a lot under that carb.
Do you think those pipes could be a touch on the small side?
Cheers
Fatty
Can't recall much about the engine, I think it had 12:1 in it, The heads flowed well, they were the Dash 9's I beleive, usual porting with a modified chamber. Harrop intake with a 1025 Demon 4150 style carb. 5.85" rod, Crankshaft Rebuilders Crank, Graeme Serini Custom specced Comp Cams Flat Tappet camshaft, 1 7/8-2" stepped primary header. It ran 9.6's or 9.7's at 145odd mph in a Gemini, the car was featured in the October 2004 issue of Australian Drag Racing Magazine.
AL...
AL...
Yes
HI LA and Fatman
How are you guys.
Yes i was a little disappointed as i thought this was going to be the biggest 383 around.
The heads are YT dash 9s and they where done up By nathan and Higgins race developments. They have 2.08s and 1.65s, massive ports on both the inlet and exh. Im using custom Falt tops by CP and have around the 13:1 CR.
Yes i reckon with the adaptor and HVH and nitrous plate I may have a little too much under the carb, but i dont know what to do as i need the adaptor to fit the carb plus i need the nitrous.
Im a little disappointed now as this engine has more than the one mentiond on this post yet im a few HP short.
I did make a few mistakes butm the pipes i used on the dyno are crap and i had the plug gap at 32 thou. I will open them up to 45 thou and that should help a bit.
What size pipes do you think i should use, 2 inch on the primaries, its in a commodore so it will be a hassle getting that size past the steering.
Also im thinking of changing from the Digital 6 to a 7 series with a crank trigger and addiing a vacumm pump, just not sure what pump, some guys reckon pumps of things like mazdas work well.
Lastly the thing gained 26 HP by going from 28 degrees to 30 in the timing.
Peak torque was strange as it hit 490 at 4800 and then dropped between 5000 and 6000 and then hit the 495 at 6150.
The HP dropped by five hp when we took it to 7000 but Theo wanted to take it to 7500 or 8000 to see what happened as he reckons engines can jump up again in the HP figure, but i dont care cause i need this engine too last and over 7000 in a holden is scary.
Trev
How are you guys.
Yes i was a little disappointed as i thought this was going to be the biggest 383 around.
The heads are YT dash 9s and they where done up By nathan and Higgins race developments. They have 2.08s and 1.65s, massive ports on both the inlet and exh. Im using custom Falt tops by CP and have around the 13:1 CR.
Yes i reckon with the adaptor and HVH and nitrous plate I may have a little too much under the carb, but i dont know what to do as i need the adaptor to fit the carb plus i need the nitrous.
Im a little disappointed now as this engine has more than the one mentiond on this post yet im a few HP short.
I did make a few mistakes butm the pipes i used on the dyno are crap and i had the plug gap at 32 thou. I will open them up to 45 thou and that should help a bit.
What size pipes do you think i should use, 2 inch on the primaries, its in a commodore so it will be a hassle getting that size past the steering.
Also im thinking of changing from the Digital 6 to a 7 series with a crank trigger and addiing a vacumm pump, just not sure what pump, some guys reckon pumps of things like mazdas work well.
Lastly the thing gained 26 HP by going from 28 degrees to 30 in the timing.
Peak torque was strange as it hit 490 at 4800 and then dropped between 5000 and 6000 and then hit the 495 at 6150.
The HP dropped by five hp when we took it to 7000 but Theo wanted to take it to 7500 or 8000 to see what happened as he reckons engines can jump up again in the HP figure, but i dont care cause i need this engine too last and over 7000 in a holden is scary.
Trev
combination
Hi trev
Whose dyno did you use?
Why dyno the motor with poor quality pipes? I guess its always best to have the pipes that you plan on running but if thats not possible, something that is at least close. Ask around, get some pipes made and get it back on a dyno.
What's to say that these crap pipes have not cost it a heap of HP. I think I'd get 1 7/8 pipes made. 3 or 3 1/4 inch collector. just a guesstimate.
What made you go for the 1050 dominator. see if you can borrow a good 950 HP to try. 4150 pattern give you a lot more options with regards to spacers.
Whose dyno did you use?
Why dyno the motor with poor quality pipes? I guess its always best to have the pipes that you plan on running but if thats not possible, something that is at least close. Ask around, get some pipes made and get it back on a dyno.
What's to say that these crap pipes have not cost it a heap of HP. I think I'd get 1 7/8 pipes made. 3 or 3 1/4 inch collector. just a guesstimate.
What made you go for the 1050 dominator. see if you can borrow a good 950 HP to try. 4150 pattern give you a lot more options with regards to spacers.
Hi
Hi Fatman
Used the Pavtek dyno with Theo operating it.
The pipes is all i had, now i have a set of Difillipo 1 7/8 4 into ones with a 3 inch collector. So they will help it.
Yes im regretting getting the Dominator, was looking at what Haddads where using and they seem to go with the dominator,
Not dynoeing it again Fatman as Im in wodonga and it means a 3 in the morning leave and get home at 10 at night just to get it on the dyno. plus 700 dollars
So im sticking with what i got now, its tuned up well and running sweet so Im happy .
Trev
Used the Pavtek dyno with Theo operating it.
The pipes is all i had, now i have a set of Difillipo 1 7/8 4 into ones with a 3 inch collector. So they will help it.
Yes im regretting getting the Dominator, was looking at what Haddads where using and they seem to go with the dominator,
Not dynoeing it again Fatman as Im in wodonga and it means a 3 in the morning leave and get home at 10 at night just to get it on the dyno. plus 700 dollars
So im sticking with what i got now, its tuned up well and running sweet so Im happy .
Trev
carb
Trev
Why don't you stick that e bay 750HP on it. venturi size is the same as the 950 with smaller throttle plates as far i am aware. Can't see the amount of air that they will move being to different.
Think it could be better than the 1050.
Why don't you stick that e bay 750HP on it. venturi size is the same as the 950 with smaller throttle plates as far i am aware. Can't see the amount of air that they will move being to different.
Think it could be better than the 1050.