be_good

i'll start off by introducing myself. i'm johnnny i got a 94 del sol and an 04 350z. but here is my problem my del sol is amazingly solw. i installed a vx transition for better mpg. that tranny killed my power. not i cant utilize the taller gearing due to the fact that the engine cant push its self. so i was wondering how can i push up the power w/out upping displacement. the 15b i got is a good runner doesn't burn any oil at all and i want to keep it . so what are my options. also i dont want to break the bank i got a 350z to mod so no turbos or superchargers

suspendedHatch

Which "15B" is it?

That transmission is designed for the D15Z1. That motor's power was deliberately made to peak in the low RPM so you could cruise at 1000 RPM.

Though the Del Sol is a few hundred pounds heavier than the VX that the transmission was intended for, I can't see it being such a big problem that you can't use the high gears. You're looking for torque, not hp, which is going to be a big problem for a Honda. You have a choice of a turbocharger OR high compression pistons. If you are underpowered, than either option will give you better mileage. I would not consider a cam upgrade if your intention is to keep your mileage.

be_good

its the 15b that comes standard in a del sol s do you think i can swap the heads with a d15z1 and be ok?? and i may have the engine # wrong i'm a nissan guy i don't know that much about hondas..lol

SpeedoKing

well first off welcome to the site, good to see a fellow Illinois honda head here. the d15b is a great engine but the only way to get power out of it is to turbo it....aside from that you are not going to see much of a power gain. the best way to get your power back is to put the original trans back on it and get rid of that vx trans. you can try i/e/h and maybe get a tune some ppl have seen ok gains with a good tune but aside from that there is no cheap way to get power of of it. the question you have to ask is, is the mpg worth the dull ride? and if you were to put the original trans back on then do i/e/h w/o a tune you will still have great mpg.


Modified by SpeedoKing at 4:54 PM 4/7/2008

be_good

with skinny itty bitty tires i was pulling 40 mps thats over the 30 mpg i was having with the old tranny. and the old trany kinda ate its self so putting it back on is out of the question. but i want to use this tranny. i can cruse 60mph @2500rpm and i like thati was just wondering if there was a head swap i could use i only need like an extra 20 hp

SpeedoKing

the head you have is a good head your not going to gain any where close to 20hp with a head swap. like mentioned earlier the only way your going to get any decent gains is with boost or high compression pistons.

be_good

what pistons do you recommend and what compression would you recommend i run

be_good

k cool thanks

Dasfinc

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SpeedoKing &raquo;</TD></TR><TR><TD CLASS="quote">the head you have is a good head your not going to gain any where close to 20hp with a head swap. like mentioned earlier the only way your going to get any decent gains is with boost or high compression pistons.</TD></TR></TABLE>

nice to see some IL honda peps posting some good info!

You can gain 10, maybe 15hp out of a D16Z6/D16Y8 Vtec head, but all that would do is give you more HP in an even higher rev range, making the transmission suck even more *I had a D15B8/D16Y8 MiniMe with a CX transmission (Same as the VX) and it sucked *****, thats why I did a motor swap and have a daily driver for gas mileage.

be_good

the del sol is my daily driver

Dasfinc

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by be_good &raquo;</TD></TR><TR><TD CLASS="quote">the del sol is my daily driver</TD></TR></TABLE>

if its your DD, don't tweak it, buy another to play with.

JDM Knight Star

the cx and vx made peak torque at very low rpms, i remember my car pulled around 2-3k (it was a cx). But it chocked around 4k all the way up till 6k redline. I replaced the stock skinny intake tube with a SRI and throttle response sucked ***, it would stall out more often but top end was a bit more. Honestly with that tranny = no acceleration. You can boost it. Boosting your car can give you better MPG if you don't get on it all the time. A lot of boosted D's around here get 35+ mpg.