Dissappointing 331 Dyno

speeddemon40

Founding Member
Nov 6, 2001
63
0
6
Kennesaw, GA
Ok...I finally got my 331 dynoed the other day...After allittle messing with FP and Timing it made 330/360. I know with more tuning it should be able to make a little more, but the guy running the dyno told me I should get a new intake, 75mm throttle body, 80mm MAF, 1 3/4" headers, 3" exhaust, and bigger power pipe and possibly new heads. what do you guys think? what intake/heads should i put on there? The TFS R intake with AFR 185s?
Thanks
BTW cam specs are 536/560 224/226 112 LS
 
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First thing I see is your BBK headers. Did you port the hell out of them? They are very restrictive at the flange from the factory. If yours are 15/8" that's even worse. I used to run their 13/4" but before I put them on I ground the welds out of the inside of the flanges. The welds stuck way out into the ports. They also have a pretty small collector (less than even 21/2"). If you can swing it, put a set of Bassani 13/4" to 17/8" steps on it with an X-pipe and 3" all the way back. On an N/A engine, exhaust gotta flow and scavenge to put up the numbers. Don't be disappointed, it takes a while to get this stuff dialed in. I think you could use some more cam also. :)
 
EMW150 said:
First thing I see is your BBK headers. Did you port the hell out of them? They are very restrictive at the flange from the factory. If yours are 15/8" that's even worse. I used to run their 13/4" but before I put them on I ground the welds out of the inside of the flanges. The welds stuck way out into the ports. They also have a pretty small collector (less than even 21/2"). If you can swing it, put a set of Bassani 13/4" to 17/8" steps on it with an X-pipe and 3" all the way back. On an N/A engine, exhaust gotta flow and scavenge to put up the numbers. Don't be disappointed, it takes a while to get this stuff dialed in. I think you could use some more cam also. :)

Bingo.... I agree with Eric, and I've seen the headers nasty. The cam is too small but I see no reason why you can't make more power with the current set-up, the 80mm and Power Pipe wouldn't hurt since they read better. You are not going to pick up a huge amount by swapping TB's, whats the compression ratio? Hows the curve look, HP and TQ?

Remember Dyno numbers aren't gospel, take it to the track and see how it runs. It will take time but once it all is dialed in and you get good clean runs then you can start making decision of what to change.
 
Why change the heads?? That's crazy talk.. ;)

Needs a good cam in there as that cam with the cubic inch is to samll and I would go for a 75mm TB and a 80Pro-M... Maybe even try ditching the Power pipe and trya straight piece.. I here it's worth a few HP....

As for the exhaust I am sure that would pick the car up some also.. This would be a good start.. I think the Intake is fine... The vortech is basically a holley and it should work great...
 
SmockDoiley said:
why are you saying dont be disappointed when your bragging about your 331 making 40 more horses?

Because you still made good numbers and not every engine combo makes the same power, even using the same components. You can't expect to dulicate #'s. And it didn't seem like he was bragging to me, more like showing what can be done.
 
Thanks for the responses guys... The only thing done to the heads are the upgraded springs. I think I may have been mislead by FPS on what power the setup would really make. They built the shortblock for me and recommened that cam based on what parts i was going with and that I was gonna put a 150 shot on it. The compression is 10.25 with these heads. The headers are 1 5/8" and but i did grind out some of the nasty weld from the inside of the flanges.
Thanks
Ken
BTW the curves looked real good..it made 300 tq starting at 3200 rpm and was smooth all the way up and it made over 300 hp at 4500 rpm. I'll post my graphs when i get back in town.
 
speeddemon40 said:
Thanks for the responses guys... The only thing done to the heads are the upgraded springs. I think I may have been mislead by FPS on what power the setup would really make. They built the shortblock for me and recommened that cam based on what parts i was going with and that I was gonna put a 150 shot on it. The compression is 10.25 with these heads. The headers are 1 5/8" and but i did grind out some of the nasty weld from the inside of the flanges.
Thanks
Ken
BTW the curves looked real good..it made 300 tq starting at 3200 rpm and was smooth all the way up and it made over 300 hp at 4500 rpm. I'll post my graphs when i get back in town.


:nice: dont feel bad bro, my 351 combo made the same numbers as yours......so your makeing more power per cube than me.... :bang: