New dyno numbers. 2.9L vs 4.0L Whipple.
- Thread starter 19COBRA93
- Start date
Traction is great. These 305" MT II's are awesome. It still spins a bit in 1st, but really digs in after that. Enough that I'm worried about my clutch now.
My suspension is stiff. It's not a drag car. I'm running the Eibach Pro-street kit with FRPP rear lower arms, relos, and an MM panhard bar. That's about it for now. I'll be adding a BMR udjustable upper, and anti-roll bar here soon.
Exhaust is 2" ARH longtubes, offroad 3" X, 3" overaxle pipes with bullets welded in, and 3" JBA mufflers. It sounds awesome. I don't have any recent vids, but I'll do that this weekend.
I also wanted to add, to get the boost down to 18lbs, I had to put on the stock throttle body. It dropped 3lbs compared to the SCJ monoblade (21lbs to 18lbs). I'm anxious to see what the new BPS tbody does on this motor, once it comes in.
Also, you can see how much the motor has been dropped when you compare pics. If you look at where the back of the blower is to the top of the firewall in the pic of my 2.9L a few posts up, then compare to the pics here of the 4.0L. It's a full inch difference.
This was as of this morning:
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Traction is great. These 305" MT II's are awesome. It still spins a bit in 1st, but really digs in after that. Enough that I'm worried about my clutch now.
My suspension is stiff. It's not a drag car. I'm running the Eibach Pro-street kit with FRPP rear lower arms, relos, and an MM panhard bar. That's about it for now. I'll be adding a BMR udjustable upper, and anti-roll bar here soon.
Exhaust is 2" ARH longtubes, offroad 3" X, 3" overaxle pipes with bullets welded in, and 3" JBA mufflers. It sounds awesome. I don't have any recent vids, but I'll do that this weekend.
I also wanted to add, to get the boost down to 18lbs, I had to put on the stock throttle body. It dropped 3lbs compared to the SCJ monoblade (21lbs to 18lbs). I'm anxious to see what the new BPS tbody does on this motor, once it comes in.
Also, you can see how much the motor has been dropped when you compare pics. If you look at where the back of the blower is to the top of the firewall in the pic of my 2.9L a few posts up, then compare to the pics here of the 4.0L. It's a full inch difference.
This was as of this morning:
hey bro i am making a engine build and will have anywhere from 800-900 rwhp. how are you hooking from a 2nd gear punch? also what size is your mt's. i just purchased the nt05r 305/35/19 hoping i can hook 2nd on the street.
Even with the cams, bigger headers, and 4" pulley, it was still making 21lbs. That's too much for pump gas, obviously. The stock tbody did the trick. 18lbs, 16 degrees timing on this tune. It's very safe.
And I just noticed, since I started this thread, I've built the motor and added big cams and bigger headers. So I guess that's an update.
I've whored it out every chance I could get in other threads, but here's a couple idle vids of the cams:
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2 gear punch it nearly dead hooks. Once the roads warm up, they should do even better. They're 305/35/20's. Your NT05R's should do just as good.
freakin awesome. i mentioned in my thread that all of the big builds should be on like a sticky big build thread.
are you stock internals i can't remember as i am typing this.
i am going with this setup
oliver I beam rods
diamond 9:5:1 coated pistons
cj double keyed crank
kb 3.6 lc 3.5 upper
ati 10% lower
fore inovation dual walboro 465's -8 feed and return
id 1300's and a spec p trim clutch
i think this winter made everyone go fast
It's now a fully built motor. But I sort of went against the grain, and stuck with the stock pistons and 8.4:1 compression.
cool what made you stick with stock compression. and what other internals do you have?
For a couple reasons really. The stock pistons are actually pretty good. They're nearly the same as the Ford GT pistons, and those guys are really making some power on them. I'm on a budget like most everyone else, so spending another $1000 for coated pistons/rings just didn't make a lot of sense to me, when I'm confident the stock pistons will handle the power I wanted to make. Also, I bought the big blower first, so knowing I had a blower capable of 30lbs, I decided to keep the compression low to take advantage of that capability. And I really wanted to be able to hammer on this thing on pump gas in any situation without worry of detonation. The lower compression tends to be more forgiving in that sense.
If I were running a smaller blower, I would have went with different pistons for higher compression.
The rest of the motor though is Manley I-beam rods, Cobra Jet crank (single keyed -as they come), Custom Bullet cams, billet oil pump gears, and ARP everything. Aside from having the rotating assembly balanced by a shop, I tore down/assembled the motor, and did all the work by myself in my garage.
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Man it's awesome that you built it by yourself. I wish I had the tolls/shop /ability to do that. I guess no one can build like someone doing themselves and taking there time with it.
Awesome job Sam! I am sure glad you beefed up the engine with good forged parts. Are you going to get the crank double keyed or pinned ? My guy pinned the opposite side of the key to avoid the weak connection as the HP and Torque keep going up with mods. Thanks for sharing your build and facts with us
KennieG52
KennyG1
Don't be running your car with that much boost on pump gas with the 4.0L !!! Maximum boost on pump gas should never exceed 17 lbs.!!......How do I know you ask????.....I just blew mine apart with 22 lbs and yes, I have the 4.0L Whipple. Was making 853 rwhp on pump tune and 940 rwhp on C16 tune. Its now apart while we await my new 5.8/5.4 Race Block being built by Livernois. Typical of most fails. No 8 Rod came apart and punched holes in both sides and the top of the block!! Wasn't pretty....lesson learned is that Shelby's stock forged internals are only rated to 750 rwhp. You can take it over that(as I did) but you are only fooling yourself to think it won't come apart very soon! Do your internals now before you end up having to replace the block as I did......its $7,000 Canadian for a bare block. I went to the 5.8 versus my stock 5.4 as it works better with the 4.0L Whipple and also gives you more displacement. Heads bolt up the same, only have to install the proper head gasket to accommodate.I upgraded to a 4.0L from a maxed out 2.9L and had it dyno'd today. This was done with no other changes except the blower itself. Same tune, same tbody/intake, same dyno, same car, etc. Stock motor.
With the 2.9L I was seeing about 23.5lbs with a 2.70 upper, and with the 4.0L and a 3.50 upper it's making about 25lbs right at the end of the pull. Once I build the motor and install the cams, the boost level should drop.
Anyway, it made 874/800. 25lbs peak, 18 degrees timing, 100 octane + torco. The biggest gain was the torque. We suspect the stock valve springs are giving up at the top of the pull.
In the next week or so I'll be pulling it all apart for billet rods, big cams, and a tubular K. But I wanted a solid comparison between the two blowers with no other changes.
The blue and red pulls were back to back, and the green lines are the 2.9L numbers.
He probably already found out like only FOUR YEARS AGO since that's how old this thread is......god and here I thought there was actually a new thread topic.
But hey KenneG52, all jokes aside try to avoid "raising old threads from the dead" Welcome to SVTP!
How many revs, though? I think it's been established that it's revs (and detonation) that do these rods in, not boost.
I really need to learn to use the "search" on this forum better. I find Sam's input really informational even if they are dated. Wonder what happened to him, he used to be a regular. Must of moved on.....
Cheers,
Ray
Cheers,
Ray
I see Sam on FB on some of the GT500 forums.
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