Boss Manifold Tuning *Dyno Inside*

[kris5597]

Thats about what i was seeing tune only, after the gt350 (i know not a boss) and headers the highest peak ive recorded was 52.15 at about 7700, the average now that its hotter than all hell has been mid 50s to low 51

Long story short your flow numbers look fine

Yessir, I would say that is a good comparison. It will be more comparable after I have tuned the VCT to see if there is any more flow/ power out of the manifold. Hopefully I will get around to it in the next few days.

Kris

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[kris5597]

Alright, I finally finished up tuning my VCT last night on my new Boss intake manifold.

First off, the car DOES NOT perform best with stock VCT. To maximize flow and volumetric efficiency at all rpms, VCT must be tuned!

While finalizing the exhaust cam VCT last night, I managed to max out my stock fuel injectors with an e65 mixture. I had to add 93 octane to lower the ethanol blend down to around E35 to finish the tuning. 90% of my VCT tuning was dyno based comparing different VCT cam angle positions on E65, during my last two pulls maxing out the injectors, I had to compare the last two pulls on E35 and then compare MAF lb/min flow numbers to the previous pulls to judge best VCT.

I will not post my VCT results, but I can tell you this, the car most certainly reacted and liked cam angles I was predicting and even towards the end, cam angles I was most certainly did not predict. My final MAF lb/min number in 70 degree weather with 100% humidity, it just finished raining and was hot and muggy, was 51.2lb at 7850rpm. Also note that I am at sea level in south Louisiana. Peak horsepower appears to be around 7600-7700rpm.

I have not done a final pull to show horsepower numbers as of yet, but I will more than likely do this today, then I will post numbers, as irrelevant as they are.

Kris

 

[Todd15Fastback]

Alright, I finally finished up tuning my VCT last night on my new Boss intake manifold.

First off, the car DOES NOT perform best with stock VCT. To maximize flow and volumetric efficiency at all rpms, VCT must be tuned!

While finalizing the exhaust cam VCT last night, I managed to max out my stock fuel injectors with an e65 mixture. I had to add 93 octane to lower the ethanol blend down to around E35 to finish the tuning. 90% of my VCT tuning was dyno based comparing different VCT cam angle positions on E65, during my last two pulls maxing out the injectors, I had to compare the last two pulls on E35 and then compare MAF lb/min flow numbers to the previous pulls to judge best VCT.

I will not post my VCT results, but I can tell you this, the car most certainly reacted and liked cam angles I was predicting and even towards the end, cam angles I was most certainly did not predict. My final MAF lb/min number in 70 degree weather with 100% humidity, it just finished raining and was hot and muggy, was 51.2lb at 7850rpm. Also note that I am at sea level in south Louisiana. Peak horsepower appears to be around 7600-7700rpm.

I have not done a final pull to show horsepower numbers as of yet, but I will more than likely do this today, then I will post numbers, as irrelevant as they are.

Kris

Dang, Kris! Thanks for sharing all of your info!!

 

[PowerAdderGT]

Nice, look forward to the irrelevant numbers ;)

 

[kris5597]

Well, I say irrelevant because I do not want people saying, oh well I made more horsepower than you with the stock manifold, or WTH, my CJ manifold didn't make that much power, and so forth.

So, for comparison sake, I will upload stock manifold tuned VCT and then do a pull, then upload Boss manifold tuned VCT and do another pull to compare results.

Kris

 

[GTBOB]

Nice work!

So do you work for someone to create tune files or do you do this for personal-hobby reasons?

 

[kris5597]

I tune for a hobby and on my owns car normally. Sometimes I'll tune other cars, but only locals. I don't like the business aspect of the tuning business.

 

[Mikeiscoo2]

the most interesting part is how you maxed out your stock injectors.

 

[kris5597]

the most interesting part is how you maxed out your stock injectors.

I found this interesting too. With the added rpm and increased volumetric efficiency at the higher rpms, the engine required more fuel to hit my fuel targets. Since the VCT changed so much and the car responded well, it pushed the stock fuel injectors to their limit. Fueling target at 8000rpm is .82 lambda and the car was leaning out to .87-.88 lambda. For safety I will have to run 93 octane until I can upgrade to 47lb injectors.

Kris

 

[Higgs Boson]

I found this interesting too. With the added rpm and increased volumetric efficiency at the higher rpms, the engine required more fuel to hit my fuel targets. Since the VCT changed so much and the car responded well, it pushed the stock fuel injectors to their limit. Fueling target at 8000rpm is .82 lambda and the car was leaning out to .87-.88 lambda. For safety I will have to run 93 octane until I can upgrade to 47lb injectors.

Kris

Sounds like you barely maxed them out....Mine didn't max out probably because:

GT350 a little bit less flow than Boss on the top?
Running .85 lambda rather than .82
I doubt my cam timing is optimized

So this does show that on E85 and a bigger intake manifold, the injectors are indeed close enough to maxing out to warrant upgrading them as Lund recommends.

 

[kris5597]

Sounds like you barely maxed them out....Mine didn't max out probably because:

GT350 a little bit less flow than Boss on the top? Probable
Running .85 lambda rather than .82 Definitely
I doubt my cam timing is optimized Probable

So this does show that on E85 and a bigger intake manifold, the injectors are indeed close enough to maxing out to warrant upgrading them as Lund recommends.

And I have catless long tube headers

 

[Plimmer]

Anyone know how 51 lbs compares to the GT350?? Stock 5.0 is about 40 lbs, so you must be comfortably over 500 crank hp by now. Assuming all fuel trims look good and MAF cal is good.

 

[PowerAdderGT]

Well, I say irrelevant because I do not want people saying, oh well I made more horsepower than you with the stock manifold, or WTH, my CJ manifold didn't make that much power, and so forth.

So, for comparison sake, I will upload stock manifold tuned VCT and then do a pull, then upload Boss manifold tuned VCT and do another pull to compare results.

Kris

I Was kidding, i appreciate your contribution to the forum and look forward to seeing more.

 

[kris5597]

Anyone know how 51 lbs compares to the GT350?? Stock 5.0 is about 40 lbs, so you must be comfortably over 500 crank hp by now. Assuming all fuel trims look good and MAF cal is good.

MAF calibration is as close to perfect as I can get it. My fuel trims are <+/- 1% everywhere.

I Was kidding, i appreciate your contribution to the forum and look forward to seeing more.

Oh I know, I just wanted to clarify for everyone else lol. Thank you for that!

 

[RSKTAKR]

I'm in for info etc for this.. I just installed Mak cat deletes, and bought a JLT HOT box intake, 47lb injectors, and a new Boss intake that I might do some porting/cleanup on. I am planning on having a flex tune done and running e85 most always. Then if I get bored enough maybe putting a small 50hp-75hp shot of nitrous on (haven't decided if I want a wet or a dry shot yet though). I am pretty curios to see how the car runs afterwards. Can you post any pics of what you shaved off on the top/back of your intake and the notch out of your hood?

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