Hello all, new to the Vr4, 400awhp plan.

[thecman02]

Yeah. Those are quoted engine brake horse power numbers. Only way 20g/ evo16g cars make over 400whp is with very expensive purpose built engines with everything right and spot on tunes. Almost every car with that turbo setup and boost is maybe at best 350whp on a mustang dyno.

To the OP the setup looks decent. A tune is going to be the biggest part of making the numbers you want. I would definitely run a larger fuel pump. I had issues with my 255 rewired around 400whp leaning out.

 

[mitsuturbo]

Holsets have proven to make decent HP, but IMO they're kind of a hack, and the BEP housings suck ass (especially for longevity). I'd personally go with an off the shelf turbo from FP or PTE, and save myself a whole bunch of headache.

 

[90ggsx]

So as promised my brother took his car to the track, he dropped the boost down to 18psi because he was scarred to break something, and he went 12.7 at 110mph and then hit a bolt on the return road and blew his rear tire haha.


any updates on the car op?

 

[GSTwithPSI]

ET seems a bit slow for that MPH. What did he trap? Slip?

 

[90ggsx]

He cut a 1.67 60ft, shifted like a grandma going into 2nd, and then shifted at 7100 rpm instead of 7500 from 3rd to 4th. So if he would have had a solid run his et probably would have been a little better. Maybe my brain isn't working properly, but what do you mean by trap? Wouldn't that just be his mph when finishing? When I go see him at house, I'll take a picture of his slip and post it.

 

[turbowop]

110mph through the traps is nowhere near 400whp. Granny shifting probably isn't really changing his trap much and adding 2psi isn't going to change it enough to put it there. I would put it closer to 300whp, but need to put it on an actual dyno to get a better estimate. And even dynos can be manipulated so they aren't always dead on either. /ubbthreads/images/graemlins/dunno.gif

BTW, 1.67 is a great 60ft, IMO. /ubbthreads/images/graemlins/rock.gif

 

[90ggsx]

...you're kidding right? Haha there isn't a car around here that traps near that with 300whp unless its an extremely light boosted car. Other than that they barely break 100. But, not everyone can be pleased, nor can they be wrong, so carry on with your day /ubbthreads/images/graemlins/smile.gif

 

[LIV4PSI]

FWIW, my Subaru traps 110-112mph, and it's makes 360whp/355tq. It weighs about the same as a VR4.

 

[turbowop]

Quoting 90ggsx:
...you're kidding right? Haha there isn't a car around here that traps near that with 300whp unless its an extremely light boosted car. Other than that they barely break 100. But, not everyone can be pleased, nor can they be wrong, so carry on with your day /ubbthreads/images/graemlins/smile.gif



My bad. I was off by roughly 50whp. My point was that the car isn't making 400whp as originally expected.

I'm also somewhat basing this on what my car traps and puts down. Last dyno was 424whp and the night before the dyno it trapped 122mph. No tuning was done between. The dyno was said to be reading low that day though by all the others that had cars on it, so who knows. And for what it's worth, my car weighs about 3440lbs with me sitting in it.

I wasn't expecting to be pleased or trying to prove that I was right about anything. The discussion was based around what kind of numbers you and everybody here thinks the car puts down. I was just adding some data points. /ubbthreads/images/graemlins/hsdunno.gif

 

[GSTwithPSI]

Quoting 90ggsx:
He cut a 1.67 60ft, shifted like a grandma going into 2nd, and then shifted at 7100 rpm instead of 7500 from 3rd to 4th. So if he would have had a solid run his et probably would have been a little better. Maybe my brain isn't working properly, but what do you mean by trap? Wouldn't that just be his mph when finishing? When I go see him at house, I'll take a picture of his slip and post it.



Sorry, my question was a little confusing. I was just wanting to confirm the car trapped 110mph, which seems low to me. Trap speed is indeed the mph when finishing (last 66ft i believe). Assuming your bro's car weighs around stock (say 3,200lbs for shits and gigs), 400whp doesn't really seem likely given the numbers you posted. Not busting your balls or saying the car isn't making power, just saying it's not making as much as you might think. With a 1.67 60ft, that car should have easily been in the mid to low 12s.

 

[90ggsx]

I agree it should have went faster, there were a couple of factors that I feel played into it as well. He spun a little through 1st because of the street tires, the car bogged a little from his shift to 2nd gear, and then not running 3rd all the way didn't allow him to get the trap speed he was looking for. It was also his first time racing at a track, and his first full pass in the car and running 10.9-11.2 afr on full e85 and still has almost 10 degrees of timing to play with.

I'm sure with the same set up, and a little seat time he could get low to mid 12's and close to if not a 115.

To the guy saying the slow shift from first to second had no effect on the car, the logs show the car falling flat on its face when he shifted into 2nd.

 

[turbowop]

Some of my fastest trap speeds were when I bogged launching or having a slow 1-2, nor has shortshifting changed it by more than 1-2mph, if that. Regardless of how well somebody can drive/shift a car down the strip, the trap doesn't change much as long as they're WOT the whole way down the track.

 

[GSTwithPSI]

Quoting 90ggsx:
I agree it should have went faster, there were a couple of factors that I feel played into it as well. He spun a little through 1st because of the street tires, the car bogged a little from his shift to 2nd gear, and then not running 3rd all the way didn't allow him to get the trap speed he was looking for. It was also his first time racing at a track, and his first full pass in the car and running 10.9-11.2 afr on full e85 and still has almost 10 degrees of timing to play with.

I'm sure with the same set up, and a little seat time he could get low to mid 12's and close to if not a 115.

To the guy saying the slow shift from first to second had no effect on the car, the logs show the car falling flat on its face when he shifted into 2nd.



Agreed that poor driving doesn't really effect your trap, but will be reflected more in your ET. With a 1.67 60ft, it seems the car came out of the hole pretty well. I don't think anyone here is trying to give you a hard time, but all the numbers just don't add up, which is why you keep getting so many questions. Maybe if you could post up that log and the time slip, what you are saying would make more sense to us.

 

[90ggsx]

There's a guy who lives down here in Idaho named John who owns an r34 and took it to the track and couldn't get passed the 11's, I don't think he even went fast enough to get booted, they then took it to imscc and Jake Montgomery drove it, and took it into the 10s with out changing anything, so poor driving does make a difference. But I wasn't saying he's a poor driver, I was just saying with more seat time, and a more solid run I feel the numbers could be better.

I'm also willing to eat my words on the power the car was making, do I still feel like its making more than 350 to the wheels, yes. 400+, no. My opinion is the track tells more than a dyno, and I was giving the car more than it had with out knowing exactly what it could do from the start. Is he going to run 10's on his current set up? Nope, at least not with out stripping the car and doing something more for more power.

 

[turbowop]

I was in the IMSCC with my GVR4. I met John, and I've known Jake for years as he's a long-time DSM guy. I guarantee you he would fully agree with what I've said here.

Maybe they had an off day with the tune on the R34 in Idaho that day. The car went 10.7 @ 139mph at IMSCC on their last and best run. I also know for a fact that they dyno tuned the car less than a week prior to IMSCC, so I'm sure a lot was changed with the tune, not to mention how much Jake was playing with the tune at the event.

Regardless, my point still stands:

Drivers get the E.T.

Horsepower gets the trap. (and also shows what kind of power a car is really making)

What kind of traps was John getting with his crappy E.T.'s in Idaho? I bet they were crazy fast for the slow E.T.

But I guess you get that since you said you agree that you gave the car more whp credit that you should have. No worries.

 

[90ggsx]

Well thank you for correcting me, I was told by someone who was supposed to be in the event that nothing had changed, just drivers.

Jake was supposed to drive the car while it was here in Idaho but the track wouldn't let him because John had already signed up as the driver, at least that is my understanding of the situation, regardless of whether my brothers car is making 300whp or 400+ whp I'll just be happy to see the thing stay together and be able to be driven home from the track. I mean, that's the best you can hope for when your race car is also your DD right? Haha

I didn't even know that was you! Not to sound like a nut swinger or anything, but your car kind of sealed the deal for me buying and building the galant gsx that I got, you sir, have a hell of a nice car.

 

[turbowop]

Thanks, dude. /ubbthreads/images/graemlins/smile.gif And BTW, I wasn't trying to bust your balls or call you out on the power your brother's car is making. Just trying to add to the discussion based on what I know about running a car down the 1/4 mile and what to expect regarding power.