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Now I am convinced more than ever that it would be better for the rest of us if you go back to inline valve heads for dragweek
 

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So, obviously I did not make it to dragweek. We hurt some parts in the bottom end on the engine dyno and I was not able to make up the time lost.
Here is the engine completed, in the car.




But now for the good news. I got the car running and driving about 2 weeks ago, put about 10 street miles on it and went to the dyno last friday. I went into the day with the goal of making sure the combination was happy on pump gas, if possible. We had C12 in the tank on the engine dyno, and the tuning window was so wide on the race fuel, that I thought I could get away with pump gas. So the first pull at the chassis dyno, I had the air fuel target at 12.5:1 and the timing at 26 degrees. I know from the engine dyno session, that at 29 degrees this thing is happy.

So first pull I was shocked to see 725rwhp, so was Paul at Total Induction where I was renting the dyno. We looked at the data, only thing I saw there as a point of concern was we are only seeing 6” of crankcase vacuum, but everything else looked happy, oil pressure was solid, air fuel was a little rich but close enough to where I knew the holley could keep up. This run I pulled it to about 8000rpm. The rest of the day I stopped the pulls between 8300-8500rpm. We could not get the car and the inductive pickup to co-operate, so I did my best to guess the RPM at peak HP by looking at dyno MPH vs my DS sensor and RPM in the datalog.



After the first pull we pulled a little bit of fuel out of it and I also adjusted the vacuum pump regulator. Next pull netted 742rwhp, but it only picked up 1” of crankcase vacuum, I decided to not mess with the regulator anymore because it should have been more than 1” as much as I moved the regulator. The oil pan has a small leak and also, I want to verify that my sensor for the holley is reading correctly before I go any further. So we added a degree of timing after that and it picked up another 7hp and we were at 749rwhp. Added one more degree of timing and it made 760rwhp. We were now at 29 degrees of timing and the fuel curve was looking happy. We tried a 12.9:1 AFR target and it picked up a small amount at peak, but lost more down low, so we stuck with 12.7:1 AFR where it seemed happier overall.



All of the above numbers were run thru the 3” mufflers and tailpipes. The dyno shop is in a semi residential neighborhood so we didn’t want to piss the anyone off too early in the day. So the plan was to get the tuneup right and pull the caps on the x-pipe to see what it did without the restriction of the catback and tailpipes. Interestingly enough, it picked up only a few HP at peak, but down low it gained 10-15hp in some places, which should really help shift recovery. After all of the testing, the best run we had was 765rwhp, peaking around 76-7700 rpm and carrying it out to about 8000-8200rpm. I am extremely happy with the results, I didn’t go into the day trying to make a number, so all of that was just icing on the cake. The car is an absolute monster on pump gas, and I was unsure of how it would go on pump at 13.2:1 static compression ratio, but the plugs did not show anything to make us the least bit nervous all day. I do need to work on the entry into the air pan though, we closed the hood and it lost a bunch of power. I know it is on a stationary dyno but I am going to see if I can test the car with the hood on and off of the car to see if it makes any difference. I really do not want to put a forward facing scoop on the car.

Here is a video from the day also, this was with the 3.5” caps on the x-pipe removed.
https://youtu.be/s3oxTGDiGSc
Very nice dyno numbers and sounds awesome!!:)
 

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I couldn't find a safety data sheet or anything that would indicate proportions, but MTBE is an antiknock agent, so that's good. The problems are it leans out your mixture and evaporates out of the fuel rather quickly. I know Mark has used it before, but I don't know if he liked it. He used to recommend Turbo 108+, but that may have changed or been discontinued. I'd send him a PM and ask what he likes.
 

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O.K. thanks. I plan on getting a carb from him and get his opinion on fuel. I'm gonna open up my clearances a little and do what it takes on the fuel side to prevent issues, done with living on the edge clearances and lifting ring lands on a street car.
 

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nice SBF! Your on an unloaded dyno though, I would take a couple degrees out and fatten it up a hair and make your first bunch of passes and let the plugs tell you how much more to walk up on it. Hella different load in real world. My eddy current mustang dyno did real good for being able to pull off dyno and send it, dynojets never have with just the inertial weight.

E85!
 

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Discussion Starter #68
Very good results well done,

Any chance you would share what cam is in this combo?
It is a 2.081 journal core, Ed knows where I live, so thats all I am telling. I will say, it is not as aggressive as it could be, and this thing drives as nice as my old highport setup did.

Now I am convinced more than ever that it would be better for the rest of us if you go back to inline valve heads for dragweek
At this point, it is looking like I will be doing the midwest drags next year.

So it is looking like I will be headed to the racetrack on sunday, I have been working on little things all week to get ready, one thing i wanted to address after the chassis dyno was the entry of the air pan to the cowl. I put a thicker insulation on it so it will be nice and snug to the hood and also got the sheetmetal up over the cowl. Pretty happy with how it turned out for having seriously limited tools for this type of work.


 

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EFI/N2O JUNKIE
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Ok, Jeffy, you give me the hit and you gotta gap me, we'll go heads-up............................. How much you wanna lose?





BTW: You can't look under my hood for any lines.............


Damn good work my man, VERY impressive!
 

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nice SBF! Your on an unloaded dyno though, I would take a couple degrees out and fatten it up a hair and make your first bunch of passes and let the plugs tell you how much more to walk up on it. Hella different load in real world. My eddy current mustang dyno did real good for being able to pull off dyno and send it, dynojets never have with just the inertial weight.

E85!
I think this has a lot of merit. With that high of a compression ratio, I'd be very leary of running it on pump gas at the track. Inertia Dyno has controlled conditions and limited load. Launching it hard on slicks and grinding it out for an entire pass could definitely load it a lot harder, and push it into detonation. Plus, engine temps and other factors not as easily controlled as on a dyno may show their hands. At least a heavy dose of Torco Accelerator (or other MMT additive) may be beneficial, and add some peace of mind. Cheap insurance for the money you've got invested in that thing... Maybe even consider running a 100 octane unleaded race fuel at the track.

Amazing build! Engine is BAD ASS!!!
 

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I think this has a lot of merit. With that high of a compression ratio, I'd be very leary of running it on pump gas at the track. Inertia Dyno has controlled conditions and limited load. Launching it hard on slicks and grinding it out for an entire pass could definitely load it a lot harder, and push it into detonation. Plus, engine temps and other factors not as easily controlled as on a dyno may show their hands. At least a heavy dose of Torco Accelerator (or other MMT additive) may be beneficial, and add some peace of mind. Cheap insurance for the money you've got invested in that thing... Maybe even consider running a 100 octane unleaded race fuel at the track.

Amazing build! Engine is BAD ASS!!!
Actually, a sub 800whp stick shift car, pulled in high gear on a dynojet, will have a slower acceleration rate, through a larger rpm span, than most anytime during a run at the track.
 

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Discussion Starter #75 (Edited)
Ok, Jeffy, you give me the hit and you gotta gap me, we'll go heads-up............................. How much you wanna lose?





BTW: You can't look under my hood for any lines.............


Damn good work my man, VERY impressive!
Thanks Mike, that sounds like some slimbo stips right there. BTW, I have been meaning to text you back, leaning out the fuel map in the area above the idle zone fixed the stalling when i kick the clutch pedal in.

I think this has a lot of merit. With that high of a compression ratio, I'd be very leary of running it on pump gas at the track. Inertia Dyno has controlled conditions and limited load. Launching it hard on slicks and grinding it out for an entire pass could definitely load it a lot harder, and push it into detonation. Plus, engine temps and other factors not as easily controlled as on a dyno may show their hands. At least a heavy dose of Torco Accelerator (or other MMT additive) may be beneficial, and add some peace of mind. Cheap insurance for the money you've got invested in that thing... Maybe even consider running a 100 octane unleaded race fuel at the track.

Amazing build! Engine is BAD ASS!!!
Thank you for the compliment. I do not agree with the statement of the dyno being unloaded though. It is still turning a 3500# roller, which is 500# more than the car weighs. I realize it is not the same, but there is definitely a decent load there. Enough load that i put a bunch of clutch in the thing, more than i thought i needed, way more than what i use at the racetrack, and it was driving thru the clutch if i didn't roll into it.

There are a few guys in Australia that have similar combos, with more compression, more RPM, and more aggressive camshafts, on pump gas, with no issues. If those guys had not already done it, i would have not tried to be the first. That being said the plan has always been to take 2 degrees out just to knock a little power out of it for the first few passes just because this thing is going to be a handful on a small tire with a clutch.
 

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Discussion Starter #76
Doc, have the Higgins heads and intake been ported?
The heads are straight out of the box from Higgins. The heads are CNC ported and hand finished by Higgins.
 

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Thank you for the compliment. I do not agree with the statement of the dyno being unloaded though. It is still turning a 3500# roller, which is 500# more than the car weighs. I realize it is not the same, but there is definitely a decent load there. Enough load that i put a bunch of clutch in the thing, more than i thought i needed, way more than what i use at the racetrack, and it was driving thru the clutch if i didn't roll into it.
Drivetrains don't usually break on inertia dynos. Launches and gear changes (especially with a stick shift) put momentary HIGH loads on the engine, which can cause it to detonate. Once detonation starts, it likely takes a little bit to go away.

If I had that kind of coin in a high compression engine like yours, the LAST place I would try to be frugal... would be with fuel... and it's not like you need the expensive stuff. I'm aware you likely enjoy the bragging rights of being 'pump gas'... but I would still add a little 'insurance' at the track.

The first paragraph is mostly 'theory' on my behalf... being the more you load an engine, the more likely it is to detonate... Take it for what you think it's worth. The engines in my mustang have always been 'stock block'... and running one of those into detonation is what kills/splits them when you're pushing their limits. I've gotten about 15 years out of the last two engines, with the last one still going strong... and that's with dozens of bottles through a 200 hp plate on one. Never split one.

If you decide to skip the good fuel, inspect the main caps carefully if/when you do a freshen-up. I was a little sloppy with detonation avoidance on the first engine in the beginning, and the caps were beat to hell. Never heard a thing... but made adjustments, and everything has been fine ever since.

Good Luck
 

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Thanks Mike, that sounds like some slimbo stips right there. BTW, I have been meaning to text you back, leaning out the fuel map in the area above the idle zone fixed the stalling when i kick the clutch pedal in.
He will out-stip the best of them! :)

Glad the tip helped ya, it can be frustrating at times!

Good to see you again at Drag Week.
 

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The rollers are 3000# if its a 248c dynojet. 2000# if 224 model. That is not a accurate load to weight however.

I had many cars 800hp range that were fine on dynojet air fuel, then on track would be different. I bought my mustang and after alot of calibration, cars were spot on with its eddy current absorber

2 degrees I dont think is going to keep it from being a handful haha, but def think smart for motor sake. That thing is gonna be wicked
 
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