Botched tune?

[jhawkins07]

Will somebody please look at my tune. Over the winterhttp://images.intellitxt.com/ast/adTypes/icon1.png (http://www.ls1lt1.com/forum/#) I had sent my TFS heads and intake to Lloyd to have them fully ported with upgraded 2.08 intake valves (http://www.amazon.com/gp/search?ie=UTF8&camp=1789&creative=9325&index=automotive&keywords=intake%2Bvalves&linkCode=ur2). When it got warmer out I had sent the carhttp://images.intellitxt.com/ast/adTypes/icon1.png (http://www.ls1lt1.com/forum/#) to get dyno tuned thinking its going to make much more power then last year. Well that was big Disappointment! Last year the car made 408RWHP and 403 FTlbs, which I thought was pretty good for a pretty much lightly ported and milled Trickflow 195 heads and a stockhttp://images.intellitxt.com/ast/adTypes/icon1.png (http://www.ls1lt1.com/forum/#) intake other than the throttle body holes enlarged to 58mm. Now I have the LE TFS heads that flowed @ 311cfm and full out ported intake, and it only made 408RWHP and 375 Ftlbs. The only difference is the new set up peaked higher than the old set up. The only thing the tuner said is I had a intake restriction (http://www.amazon.com/dp/B003Y7YJG2). So I looked into it and decided to change the cold air intake to a ls1 lid conversion with the SSRA megamouth. Now before I go back for more tuning I just want to make sure everything is good so I don't waste more money again. Thanks in advance!

The build consisted of all forged 383 with 11.6 c/r, LE tfs heads, LE intake, LE custom grind cam 236/244 at .606 lift, 1.6 Roller Rockers, Pro magnum lifters, 36lb injectors, 58mm throttle body, ls1 lid conversion, Areomotive Stealth 340 fuel pump with the racetronix wiring harness, long tubes and magnaflow exhaust.

[blackbirdws6]

Couple quick questions. Same dyno? Only thing changed was the heads? Do you have pics of the dyno graph?

Peak cfm numbers on heads are nice but there is more to it like anything else. I would struggle to think you have an intake restriction if you are getting the same peak number as before. Perhaps that is the case if it's hitting that peak sooner in the rev range.

[jhawkins07]

Couple quick questions. Same dyno? Only thing changed was the heads? Do you have pics of the dyno graph?

Peak cfm numbers on heads are nice but there is more to it like anything else. I would struggle to think you have an intake restriction if you are getting the same peak number as before. Perhaps that is the case if it's hitting that peak sooner in the rev range.

Yup, same dyno, and tuner. The only thing I changed was heads and intake ported and welded to match port the heads.

[jhawkins07]

33068heres the dyno graph with the new heads

[SSlowBoat]

Possible too much head? I've heard there can be too much on a na build unless you're spinning it to where you can take advantage of that cray flow

[jhawkins07]

Possible too much head? I've heard there can be too much on a na build unless you're spinning it to where you can take advantage of that cray flow

yea, but wouldn't you think it would make more then less flowing heads?

[SSlowBoat]

No, less restriction, less velocity. I'm probably wrong, but just throwing it out there.

[jhawkins07]

No, less restriction, less velocity. I'm probably wrong, but just throwing it out there.

idk, all I know its getting pretty frustrating to say the least! :(

[blackbirdws6]

What air/fuel was the tuner targeting? Did you get new springs with the heads? Please post the prior dyno graph.

[jhawkins07]

33073
What air/fuel was the tuner targeting? Did you get new springs with the heads? Please post the prior dyno graph.

I honestly couldn't tell you what afr he was aiming for, I would assume 12.8ish but Im not for sure. yup its got the lunanti 74777 valve springs which Lloyd had set up for the cam.

[blackbirdws6]

Well it seems your fueling needs more work. The older graph shows air fuel in the 12-13 range whereas the new has it going mid to high 13s. The power curves look pretty similar. Dyno could just have been reading differently.

[gmpowered]

Im sure lloyds heads are doing their job just fine.
As far as a botched tune most mail order tunes will have a better fuel curve than that.

Usually you want the curve to be richer in the peak TQ curve (mid 12 low 12s) and then lean it out towards 13.0 to shoot for max HP.

Every motor will want slightly different fuel and spark but the idea behind the fuel curve is the same.

Timing should do the same, in the TQ peak it should be moderate increasing to red line.


With that said with a proper fuel curve im willing to bet you could pick up 20+HP and power wont drop off as quick towards 6k.
Car looks like its breaking up after 6k as well.

[jhawkins07]

I agree I think heads are doing what there suppose to. After looking at the tune to he only set the timing around 28 degrees total at wot way less than the stock timing tables. So I was thinking that could be another culprit to.