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Hey Phil, i'm really diggin this. Can you elaborate a bit more on the sc-to-manifold adapter plate. Looks like a pretty abrupt restriction since the new sc opening is much larger.
It looks like it is restricting it all the way to 275HP.....rotfl
 

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how much HP can the stock trans handle?
AFter over a year I blew up the 5 speed(essentially same as our 6 speed) on an autox by unloading my 12" slicks and loading them up again with about 360-370HP behind it. That said, I have been driving like this for a year! As long as you don't drag launch it, no problem.
 

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We ran the stock fuel pump on the XP car with 750CC injectors running about 370HP with the turbo setup. This ran for about 1 year until the pump gave out. We decided to replace it with a Bosch -030 motorsports pump with swirl tank etc to stop the fuel starvation issue. The stock pump with 550s should be good all day long.
 

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Charlie,

We were running at 325RWHP and targeting 12.5-13:1 with the VP C12 race fuel which can run leaner on the 750ccs. We topped out at 282RWHP on the 550s. That was turbo limited rather than injector.
 

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rob, the injectors are running at 100% DC and the AFR's are going above 13, what does that tell you ? 440s and 550s, with only a minor change in the RPM they max out.

i think vf are planning something.

Charlie,

I could be mistaken, but I am pretty sure all the ForcedFed cars including the 340 and 380 used the stock pump. Maybe Casey will chime in. I wonder if the car you took the data on had a fuel pump on its way out. That's what happened to my car while on the dyno with Kris after a year or so on the 750ccs. when we pulled that pump out of the tank after, it would make stock pressure but deliver zero volume. Yanked it for another new stocker and it was fine. While we had the tank out we made the swirl tank etc etc.
 

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Additionally, the MP62 hits a pricepoint. The tooling is likely fully depreciated. Eaton is probably splitting the market into 2 tiers, high and low-end. They will have to pay for the TVS tooling AND they charge a higher price on the TVS because they can. Ultimately, the price is what keeps an intercooled TVS off the market. Lastly, you get to a point of diminishing marginal return. That is to say 10psi on an 11.5:1 compression motor is the practical limit on pump gas. The fairly horrid efficiency of the MP62 at that pressure ratio is compensated by the intercooler. The TVS is more efficient, so it doesn't need the IC to cool the air at that pressure ratio. Would it be cooler with an IC, sure, but not alot. Is 10-15 potential horsepower worth the loss of throttle response and the extra $1k-$1.5k for the IC setup? Undoubtedly a few of you will answer "yes". But how many people would at that pricepoint? Could a company make a business case for it?
 

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1. Any time you increase horsepower you increase the engine stress and could reduce longevity. Small price to pay for countless hours of top-quality entertainment!

2. Yes. Clutch being #1. Valvesprings should be upgraded, but I would recommend that for anyone, stock or otherwise.
 

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This like the universal horsepower threadrotfl

The valves and springs are to help firm up the prone to float valvetrain. I would suggest that as people get more power, they use that as an opportunity to try and live below 8,000 and their motors will live a healthy life... There's plenty of NA and SC'ed mills that have floated valves, broke stems, etc in the above 8,000 rpm range on stock heads...


Best,

Phil
+1 I have seen 3 autocrossers break valves with rev limiter time of only a couple of seconds.
 

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Jim,

You're welcome. And I bet you didn't think you would need that beefier exhaust! You should put in the Eibach valvesprings. I've never heard of anyone breaking the valve train with those in it.




I put 100 miles on the TVS today. Out checking the A/F's.

My 7" 2bular with 3" center is sounding real nice. (thanks Fred)

The water temp was 2 degrees lower than normal. Could be the weather.

80 degrees today instead of 90.

I miss the loud SC whine. I have an aftermaket cold air intake and you could really hear the whine before.

Phil's EFI map ran great. Running rich but better safe than sorry.

I have my Redline at 8000 rpm. I don't trust the glass engine / valve-train.

Nice increase in HP and torque. My gps data collection confirms my butt dyno impression.

I may go to the drag strip tomorrow and the dyno for sure next week.
 

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:eek: Are you serious? I just bought the Fidanza which is rated at a mere 200 lb-ft...
The HD pressure plate with the organic disc is rated to 233lb-ft. You want margin though for drag racing etc. The 6 pad sprung hug race disc with that pressure plate is good for 298lb-ft. You can go to the extreme pressure plate to hold more, but who needs a leg breaker? I would probably try the HD + street disc until it breaks.
 

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Do you get any chatter with the 6 puck?
Yeah, a bit but its fine for a dedicated auto-x car. We are moving to something similar to what Kris is showing.
 

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I think that's the ultimate endorsement for BOE's FTL clam :cool:

Good point. I'll give it a shot:

"Non-tilting Lotus Clams make baby Jesus cry"
 

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The twin screw that Fred (fzust) is running: is that the same as a TVS or is that an uber-TVS (for the Non-germans: better than TVS).

Mine is a Twin-Screw blower from Lysholm, same as on the FordGT, where as the TVS is still technically a roots, same as on the new ZR1. (Ford vs Chevy deathmatch showdown!!!!) I believe it does its compression on the outside vs. between the lobes like the lysholm. The Lysholm also has a compression rate longitudinally along the screws i.e. the screw threads get tighter toward the exit. What does all this mean? Good question. Both have much higher efficiency than the MP62. I think the TVS has a broader high efficiency range than the Lysholm, but I am not sure. Oh and lastly, my blower is 1.6L/rev vs. 1.2L/rev for the TVS or 1.0L/rev for the MP62. The reason this is important because of sizing the blower to the right air usage. If the blower is too big, you have surge problems down low. If it is too small you have to rev it too high and add alot of heat. The TVS wasn't available when I did my bespoke kit and I needed the headroom to get up to crazy horsepower. I think the 1.6L is too large for non-racing applications. 1.2L is about perfect.
 

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From what little I know, I suppose the best part of the TVS is that you can make more power, higher boost, without the need for an intercooler, and that leaves room for upgrades (with internal motor upgrades, of course). In other words, it's a better platform to start with, whereas the MP62 needs to be sort of "maxed out" to match the TVS. Maybe maxed out isn't the right words, since I know VF has a stage II with more power, but surely it has to be getting there...


If you're looking to make 280-300whp, the VF is a great solution as well. I was impressed by Matt's dyno sheet from his VF kit.
Fair point. My intercooled twin-screw on the XP car makes about 350-370HP crank. Last weekend at the auto-x, I had a leak in my A/W IC setup that put an airbubble that starved the waterpump. Ultimately, we ran it without the actual cooling. Once it heatsoaked, The highest IAT I saw was only 176F! This is running 14lbs of boost with ALOT of timing on stock compression(VP C12).
 

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Very impressive Fred... Try that with an MP62 now ... LOL
We actually had alot of debate on going with the Lysholm 1.2L blower I have in a box here or the 1.6L. PES just finished building this really trick 240Cup car for World Challenge that had a 1.6L Lysholm. Tony said it made rediculous power (Over 300 to the wheels) with zero lag. The debate was if the 1.2L would have better response but ultimately limit power to 350HP or so. Ultimately, PES convinced me that the 1.6L was the way to go. Tony said it feels like an LS7. I have ZERO regrets as you can imagine. That car is a freaking monster.
 

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Hmmmm. Had a turbo on it for 2 years. Lag is too much for AutoX. Even small turbo, still sucks. IF you only accelerate for 40 feet, you can't give 10 feet up to lag. So yanked the turbo.

Wait, wasn't thread about PHil's TVS blower? Hmmm maybe if we want to talk about intercooled Eaton kits or Twin-screw XP cars we should take that to our own threads????;)
 

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Phil,

Thanks again for doing this great work and sharing it. A lot of us are quite interested in joining you :)

A couple of points:
  • You say "torque is power". Of course, power = torque x rpm. I think you mean torque causes acceleration (and the feeling of acceleration). Power gets you top speed by overcoming aerodynamic drag (& rolling resistance).
  • I assume that the drop in boost pressure results from the different valve timing kicking in and the engine being a more efficient air pump in consuming the output of the supercharger. Does that imply that the rpm at which the valve timing changes should ideally be lower?

Thanks,

Joe

Joe, I'll take that question. No it doesn't. Ultimately you tune the crossover to maximize torque & power and make as smooth a transition as possible. Depending on VE and flow dynamics etc, this may not equate to smooth transition in boost.
 
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