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Since I ran a Katana for quite a while before switching to the intercooled VF kit I figured I could chime in on what some have called "doughy" throttle response.
Simply stated its a hardly noticable difference...the car's throttle response is far from slow. Your experience may vary but IMO the IC setup is still very responsive. Get on it and she goes!

The TVS looks very promising and it has many good qualities without having to plumb an IC and I see the pros as an easier and lighter installation with similar IC results. Keep in mind an IC mp62 made a little more power/torque at around 1 lb less boost than the TVS...of course there are differences between dynos but that tells me the TVS is great, and dont count out the mp62 when intercooled.
 

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... Keep in mind an IC mp62 made a little more power/torque at around 1 lb less boost than the TVS...
Also keep in mind that Phil's car has significantly lowered CR. That alone will make a big difference in the torque. It also is not tuned for that lower CR, so it probably does not take advantage of the additional spark advance that might recover some of that lost torque. I would hazard a guess that the lower CR would result in a 10-15 ft/lb loss.
 

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Also keep in mind that Phil's car has significantly lowered CR. That alone will make a big difference in the torque. It also is not tuned for that lower CR, so it probably does not take advantage of the additional spark advance that might recover some of that lost torque. I would hazard a guess that the lower CR would result in a 10-15 ft/lb loss.
Understood...and again if you gain back at least 10ft lbs TQ to compensate for lower CR than you would be around where I am...184tq, although I'm still running with 1 lb less boost.

Is it also true that a lower compression runs cooler temps? Someone mentioned that to me but Im not sure how much cooler the difference could be.

As far as spark advance, my car is running a conservative 91 octane tune even though I am in TX where premium fuel is 93 oct. I bet with a little adjustment to the timing we could have squeezed more power out of the tune but we opted to keep it conservative. I am not sure what timing Phil started with, since he mentioned they only adjusted fuel when they did the TVS dyno.
 

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I paid $1313 for my short block (NEW from 1st Toyota Parts). New head complete was $600 - $1913 (there was no tax and shipping to my door is about $137) -- I didn't need to get a new one, but was interested in cost. I believe upgraded head from Monkey is $1100??

Phil, less weight, tis good! :)

Not sure what the concern is about tuning, the kit WILL need a tune, just no way around it. EFI makes the process a little easier (since Phil can simply Email to EFI users), but this could be a great opportunity for Charlie to work out something on stock ECU also.

Rob
 

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Understood...and again if you gain back at least 10ft lbs TQ to compensate for lower CR than you would be around where I am...184tq, although I'm still running with 1 lb less boost.

Is it also true that a lower compression runs cooler temps? Someone mentioned that to me but Im not sure how much cooler the difference could be.
Peak numbers are very similar, but I don't think the powerband would be near as meaty with the MP62...
 

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Peak numbers are very similar, but I don't think the powerband would be near as meaty with the MP62...
Take a look at this dyno...peak TQ is at around 5500 rpm and it stays high (~175+) almost all the way to redline...which by the way was reduced to 8200. If we kept the 8500 rpm the peak numbers may have been even higher.

Even at 3500 rpm its very meaty! :D




I dont want to sidetrack Phils thread...What he has done is good for the community and the TVS is no doubt awesome. I just dont think the IC'd mp62 is as bad as some make it out to be. :shrug:
 

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I still would like to see the graphs with the fuel press, BSFC, Lambda, injection time, and peak torque.

Maybe soon I can generate them myself. I'm really curious.

I'm also not going to take a strong stand on either position. I agree that if the pump is relatively inexpensive than why not use it for piece of mind anyway, but at the same time I have personally not run into any limitations (yet) with the stock fuel system in engines that have produced over 350 Hp, repeatedly.
 

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Agreed, I went out and bought the adapters i needed to connect to the special fuel clip, and spare fuel line just in case ! i've got the pressure transducer and just added a fuel pressure gauge to my tuning software, so i'm all ready to start the testing all i need to do now is head to the dyno.

however i'm pretty sure i'm just going to backup up what we've already seen, unless someone can give me another reason as to why 550cc's at 100% DC aren't delivering enough fuel for 270RWHP.

The stock NA pump is 160, the S220 uses a 160, the S240 and S255 use a 190 high flow, the gt3 cars i believe are using the 255 high flow (but are at least 190's).

And like Kris says, if its under question, why not just change it out, it won't hurt.

Kris, are you running a return system on those cars ?
 

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With boost the returnless fuel system is not that great because you get a significant pressure drop at higher flow levels between the reg in the tank and the fuel rail, plus the pressure differential between the rail and manifold drops under boost. 270 whp should need 350cc injectors so something is up if 550 cc injectors are reaching full flow.
I would not recommend the RC 550 injectors - they have a horrible spray pattern. We gave up on them a long time back and use RC 650cc injectors as a starting point for boosted applications. For NA, the 410cc RDX injector is the best due to its spray pattern (and they are OE reliable, and cheap too).
 

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Just to toss this out, I was running a V8 DOHC FORD 4.6 on a 190 pump putting out about 331 wHP and never had any fuel pressure issues even under race conditions. Stock fuel rails with bigger injectors. It was a returnless FI system. Fuel cell obviously but still, I think a 160 should be plenty for a 1.8 litre even with lots of boost.

But I plan to install a FP gauge also and data log it, just to see.

Also agree with dstevens on the RC 550's -- I ran my own injector tests on them post motor expire, they all worked as expected, but the spray pattern seemed to coarse compared to the stock 440's. I'd like to see a working alternative to the RC 550s -- especially since the connectors don't really fit the 2ZZ. I also suspect the RC 550s might be responsible for the idle hunt I have (tuned most of it out but still a little hunt left).

Rob.
 

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I had a tonka truck that ran on an electric motor, the elise has electric windows in it so therefore the stock fuel pump ought to be ok.
brilliant
 
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