383 needs torque
10-02-2011, 07:59 PM
#1
Intermediate
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383 needs torque
My fresh 383 did not get to the get the "massive" torque numbers I had hoped for.
383, 10/1 compression, AFR 195s, Exotic Muscle LT, Comp Cam XFI280, 42#ford injectors, 1.6-1 rockers, Forged Eagle crank, Mahle flattops, ported LT1 intake opening to fit 58mm BBK, ZF6, singlemass flywheel. Dyno tuned by a local
Local builder. Took advise on parts combo from forum 383 guys.
Makes 412 rwhp
388 rwtq
I understand that most 383s make at lot more torque (like 450+). Runs good at track day, not totally unhappy, expected so much more for the $$$$$.
Really appreciate some suggestions, Please..
383, 10/1 compression, AFR 195s, Exotic Muscle LT, Comp Cam XFI280, 42#ford injectors, 1.6-1 rockers, Forged Eagle crank, Mahle flattops, ported LT1 intake opening to fit 58mm BBK, ZF6, singlemass flywheel. Dyno tuned by a local
Local builder. Took advise on parts combo from forum 383 guys.Makes 412 rwhp
388 rwtq
I understand that most 383s make at lot more torque (like 450+). Runs good at track day, not totally unhappy, expected so much more for the $$$$$.
Really appreciate some suggestions, Please..
Last edited by 94LT1Z07; 10-05-2011 at 09:06 PM. Reason: correction
10-02-2011, 09:09 PM
#3
The XFI 280 cam is fairly tame... LT1 heads are fairly limited... I converted my 1206 intake Gen1 heads to work with a LT1... next the LT1 intake fairly decent I converted my HSR modified to a 1206 intake... and 12:1 comp 383 cant wait to dyno this combo
Sorry, not putting that combo down it is very respectable!!!
Sorry, not putting that combo down it is very respectable!!!
Last edited by THE 383 admiral; 10-02-2011 at 09:19 PM.
10-02-2011, 09:36 PM
#5
Le Mans Master
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Short runner LT1 intake is going to compromise torque over Hp.
http://xtremecarzone.com.au/index.php?showtopic=386
CF member Neat got 414 /396 on a similar AFR headed Gen 1 383 build
383
TPIS miniram 1205 size ports
Comp Cam XFI cam 08-467-08 (230/236, .576/.57, 113 LSA,)
http://xtremecarzone.com.au/index.php?showtopic=386
CF member Neat got 414 /396 on a similar AFR headed Gen 1 383 build
383
TPIS miniram 1205 size ports
Comp Cam XFI cam 08-467-08 (230/236, .576/.57, 113 LSA,)
10-02-2011, 10:10 PM
#6
Drifting
Here's your same basic setup being tuned on a Dyno by Brian at PCM for less. These are more in line wiht what I've seen from that cam. I've used it several times and have seen ti make some big ole' numbers.
Typically around 525-540 on an engine dyno. Should be about 425 RWHP on an automatic. The XFI makes good power from about 2500 on up to 6600. I like the idle quality for a good sized cam. I'm a big fan of the 113 LSA also.
http://youtu.be/ukN7iQTzBNQ
Typically around 525-540 on an engine dyno. Should be about 425 RWHP on an automatic. The XFI makes good power from about 2500 on up to 6600. I like the idle quality for a good sized cam. I'm a big fan of the 113 LSA also.
http://youtu.be/ukN7iQTzBNQ
Last edited by 1963SS; 10-02-2011 at 10:17 PM.
10-03-2011, 09:46 AM
#7
Safety Car
What kind of dyno and what CF did they use?
400ish RWHP on a dynojet is about what I'd expect out of your combination. Very respectable numbers considering the low compression ratio.
Will
400ish RWHP on a dynojet is about what I'd expect out of your combination. Very respectable numbers considering the low compression ratio.
Will
10-03-2011, 11:02 AM
#10
Team Owner
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St. Jude Donor '05
too many get way way hung up on dyno numbers and internet bs
Use it as a guide, reference tuning tool. Its not a be all end all
As said, some dynos ready lower than others so keep that in mind.
#fluffing is also very common to the unknowing customer.
. The only guys dyno #s really impress or should say start foaming at the mouth over are the youtube addicts who will never race the car such as you are.
Enjoy your ride and have fun with it.
Use it as a guide, reference tuning tool. Its not a be all end all
As said, some dynos ready lower than others so keep that in mind.
#fluffing is also very common to the unknowing customer.
. The only guys dyno #s really impress or should say start foaming at the mouth over are the youtube addicts who will never race the car such as you are.
Enjoy your ride and have fun with it.
10-03-2011, 11:11 AM
#11
Drifting
Use it as a guide, reference tuning tool. Its not a be all end all
If I go to a dyno, any of them, I'll just work with the numbers it gives to achieve maximum effort from the engine. If I start with 250 HP and end up with 270 that's just as good as starting with 350 and ending up with 378. It's all just relative. Of course, the 378 HP will make you feel better.With the excellent AFR 195 heads and my personal favorite pistons I would have expected more torque also. The HP seems close. Do you have a copy of the dyno run that you could post so we could see at what RPM it's getting these numbers? Automatic or manual and what converter?
10-03-2011, 11:14 AM
#12
Safety Car
There's nothing wrong with wanting to know if his power numbers are low. I agree with you dyno numbers aren't the end all but they can also help in many ways that people fail to mention.
Something the op can do is ask in his regional forum if anyone has dynoed their cars at that same dyno. If a stock c6z06 dynoed 250 rwhp then maybe you have 700!!!
Something the op can do is ask in his regional forum if anyone has dynoed their cars at that same dyno. If a stock c6z06 dynoed 250 rwhp then maybe you have 700!!!
Last edited by 5abivt; 10-03-2011 at 11:17 AM.
10-03-2011, 11:17 AM
#13
Le Mans Master
It sounds like it could be a mustang dyno, etc. I like dyno numbers when they are compared to my previous dyno numbers and I pick up 30rwhp
but don't really sweat it compared to others. @1963SS What springs do you run with the 280xfi and how long do they hold up?
10-03-2011, 11:27 AM
#14
Team Owner
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St. Jude Donor '05
didnt mean to discourage him from looking for more power by my post fwiw.
Example..about 10+ yrs ago I took my Camino to Bob Jennings Dyno to have him work his magic with the distributor/carb. He used an ancient (term??) water brake dyno. Had an honest 375-390chp motor at the time 2800 stall etc.
I about cried when my dyno sheet read 180rwhp/230lbs tq.
I didnt get it. Car ran great though so............shouldnt have told so many buddies it got dynoed, was hard explaining that one .
Example..about 10+ yrs ago I took my Camino to Bob Jennings Dyno to have him work his magic with the distributor/carb. He used an ancient (term??) water brake dyno. Had an honest 375-390chp motor at the time 2800 stall etc.
I about cried when my dyno sheet read 180rwhp/230lbs tq.
I didnt get it. Car ran great though so............shouldnt have told so many buddies it got dynoed, was hard explaining that one .
Last edited by cv67; 10-03-2011 at 11:30 AM.
10-03-2011, 11:43 AM
#15
Drifting
@1963SS What springs do you run with the 280xfi and how long do they hold up?
I did buy them used from a friend of mine that said he only had about 500 miles on them and I didn't check the pressures when I installed them. I just set it up for 1.8" and went with it. Because the Patriots have a good reputation and they decided to send me another set if I returned the old ones. I've got another set in there now.
The installed height is 1.790 and 148 on the seat and 375@.600. I'm running LS7 lifters and Comp Pro Mags (that will soon be for sale) with the new springs. I'm going to re-check the pressure in about 6 months. I don't know if I've had bad luck or if the cam ramps are too crazy for sustained street use.....since you asked.
10-03-2011, 12:45 PM
#16
Safety Car
How does the dyno curve look like? have any pics of the graph? Do you know if the readout says mustang dnny or dynojet etc? what heads are you running the comp ports? chamber volume? 10:1 is a little low too.
10-03-2011, 01:38 PM
#17
Race Director
My fresh 383 did not get to the get the "massive" torque numbers I had hoped for.
383, 10/1 compression, AFR 195s, Exotic Muscle LT, Comp Cam XFI280, 58mm tb, 42#ford injectors, 1.6-1 rockers, Forged Eagle crank, Mahle flattops, ported intake. Dyno tuned by a local Local builder. Took advise on parts combo from forum 383 guys.
Makes 412 rwhp
388 rwtq
I understand that most 383s make at lot more torque. Runs good at track day, not totally unhappy, expected so much more for the $$$$$.
Really appreciate some suggestions, Please..
383, 10/1 compression, AFR 195s, Exotic Muscle LT, Comp Cam XFI280, 58mm tb, 42#ford injectors, 1.6-1 rockers, Forged Eagle crank, Mahle flattops, ported intake. Dyno tuned by a local
Local builder. Took advise on parts combo from forum 383 guys.Makes 412 rwhp
388 rwtq
I understand that most 383s make at lot more torque. Runs good at track day, not totally unhappy, expected so much more for the $$$$$.
Really appreciate some suggestions, Please..
10:1 compression with a 280 cam means dynamic compression isn't that high.
42# injectors MAY not perform QUITE as well as size-appropriate 30# injectors (for that setup).
Tune could be off somewhat.
180 heads make more torque (esp when dynamic compression is lower).
Is the car an automatic?
What size is the exhaust? What config? CATS?
How good is the intake porting -- esp compared to an LT4 intake?
Stock windage tray?
Cam configuration? (adv, straight, or retard)
Dyno accuracy?
Engine oil weight (heavier than 5W-30?)
Gears?
Running temp when dyno'd?
10-03-2011, 04:28 PM
#19
Safety Car
The numbers seem good to me. The cam is on the large side with wide lobe seperation, the compression is a little low, power curve is typical of LT1 intake. Overall I thought it made good power and good torque for the combination.
