My 72 LS Vega

[RockDaddy]

I was in a thread (might have been mine) where we talked about brake options. I was looking for something in all in one box and bolt on. Ended up buying a kit from Jegs someone talked about before. looks real nice.

http://www.jegs.com/i/Aerospace+Compone ... 0/10002/-1

[RockDaddy]

Probably have some good updates in a week or so.

The changes to date from last years engine is.

Mast Ls3 black label heads
~.800 lift solid roller
14.4 CR gas ported pistons
Dry sump oiling system.

And the testing is going to start using this:

[waybad]

SWEEEEEEEET,, when will you be testing at the strip? better lower the bars

[RockDaddy]

Engine looks to be about ready for dyno time next week. I might start running 1st week of May.

[RockDaddy]

I also had pretty much all the rear suspension changed out. It is a million times better than before.

[waybad]

SWWIINNGGGGG

[RockDaddy]

Just a little update. I'm a couple weeke behind as everyone is used to but the engine got a little engine dyno time today. After some warm up and break in load we had to play around a little to get some fuel and timing setup for the e98 which I imagine is a little odd (I'm not a turner) When it came time to make some actual power pulls to see where we were it quickly tapped out the 65lb injectors at 6000rpm so we didn't get much in the way or tweaking. I should have some 83lb ones in tomorrow morning. 700hp at the crank is what would make me happy and anything better is all gravy. It looked like it made 640hp when we cut it off and Rich said it was just winding up. Power started moving in good at the high 4k range with a 140hp increase from 5k to 6k when we cut it off. (if I remember correctly) We haven't played with timing or much of anything really so I'm feeling pretty good I will get to the 700 mark which should put the little Vega into the 8's.

Hopefully the good vibes continue for tomorrow when we really get to play with it. Fingers crossed!

[waybad]

[72 SS PNL]

i think youll tap out the 83's quickly running e98 , i dont see why you wouldnt exceed 700 with ease

[RockDaddy]

i think youll tap out the 83's quickly running e98 , i dont see why you wouldnt exceed 700 with ease

Well I I hope they last until peak power but as of now I have no idea where power will fall off rpm wise. using 65lb and 6k rpm basic math says Ill tap them out at around 7800 which sucks as I don't want to be pushing such a high DC. I should know today. Hopefully I don't have to spend any more cash on injectors.

[RockDaddy]

Yep we tapped them out fast. But it make me think we are not going the correct direction. I remember reading on some forum about how you misleadingly feel like you need to keep adding fuel. Ill have to do some Googleing tonight. With the 83's we only got to 6500rpm and made 690hp. So 500 RPM and 40 more HP then tapped. ERRRR

[72 SS PNL]

its the ethanol , usual rule of thumb is 1.5-2 time the amount of alky to equal that of gas

told ya 700hp wouldnt be a problem , lol just sucks the inj tapped out so quick , i think that motor has 750-770 in it , if you can get above 7500

[RockDaddy]

I just posted this on an e85 forum but I might as well spread it around Also I know "alky" usually talking about methanol is about 2:1 and ethanol it seems is closer to 1.3 to 1.4 as far as I can tell.



"OK looking for some injector sizing help. I do the calcs, read what I can but is what I'm seeing real?

Basic Info
416 LS based N/A drag motor running e98
14.4:1 comp
.800 solid cam yada yada yada

Engine on the dyno the last 2 days.
Day 1
65lb injectors maxed out at 640hp @6000rpm

OK Day 2
83lb injectors maxed out at 690hp @6500rpm


I'm not sure the BSFC of e98 exactly but using the calc:

(HPxBSFC)/(# if injectors x DC) = x LB/HR

If I backward Eng what I'm seeing with my numbers assuming my DC was really closer to 95% before we stopped her I would have to assume a BSFC of .9 for e98


(690 x .9) = 621 (8 x .95) = 7.6

621/7.6 = ~81 lb/hr which is about what I was running.



Does this sound correct? Could it really be drinking this much?
Lets say the engine was expected to make 775 @ 8k

So does that mean I need ~110lb injectors? This sounds crazy. Could it be true or are we doing something drastically wrong on the tune to be maxing out what we have so far looking for peak HP?


I really only want to buy injectors one more time. So unless someone tells me I'm crazy it looks like I need 110lb/hr assuming .9 BSFC


HELP?! "

[72 SS PNL]

what are you running for fuel pressure ?

also raising the fuel pressure will effectively make the injectors bigger , you might wanna try raising the fuel pressure about 10 psi

[RockDaddy]

Moved it up to 60psi when we buried them. We have 120's on the way now. Hopefully have something in the next couple days. It should make power somewhere around 8000rpm so I believe I am going to see my HP than I was expecting. Which is sounds good to me!