Title: max power from very small cc on a strict budget Post by: rebel on November 26, 2008, 22:02:09 pm Hello!
There's a new idea started among my friends. One of us is planning an engine. Well, nothing very original :) But, The horizon is far away due to worlds financial situation. So, we'd like to modyfy his current engine for max pewer spending minimum money - still collecting parts for the bigger one in the future. The chalenge is: Without changing displacement, crankshaft making as much HP as possible. How far cen we go modifying stuff like heads? including bigger valves, camshafts... You know - cheap tricks :) Double DRLAs (36) are a must o course... Any ideas? Title: Re: max power from very small cc on a strict budget Post by: Diederick/DVK on November 26, 2008, 22:06:57 pm i'm not an expert, but by using as much as you have already you'd be best off with;
1600, stock cam but with 1.4 rockers, as much headwork as possible, up CR to 8.5:1, use a good distributor and tune you carbs well. power pulley might work too if it doesn't overheat ;) otherwise there are some good recipes on here. think of zach's 1600. Title: Re: max power from very small cc on a strict budget Post by: rebel on November 26, 2008, 22:15:41 pm thanks for reply :)
Trick is we've got a 1300 double port to work with :D Wonder what can we achieve with that kind od dispracement :D Title: Re: max power from very small cc on a strict budget Post by: Diederick/DVK on November 26, 2008, 22:17:27 pm do you have bill fischer's "how to hot rod VW engines"?
that book definitely shows some neat tricks!! Title: Re: max power from very small cc on a strict budget Post by: Jim Ratto on November 26, 2008, 22:27:18 pm honestly, with some careful work, I see 80hp (flywheel) happening, easily.
With some trick head work and radical cam timing, maybe 100-105. spend the money on balancing parts, good valve job, swivel foot adjusters, solid rocker shafts. Engle 110 with stock rockers, 9.0:1, and your Dellortos. I don't think a lot of port work is going to do much good on this small cc if you have dual ports. I'd match manifold to intake port, shape the boss around guide and smooth port into seat. What size venturies are in the carburetors? Title: Re: max power from very small cc on a strict budget Post by: rebel on November 26, 2008, 22:34:34 pm Wow, that's what I was actually thinking about!
Almost all of us (11) have a pair of DRLA on their engines (1600-2400), so there is a wide choice to check which ones would suit best :) Title: Re: max power from very small cc on a strict budget Post by: Jim Ratto on November 26, 2008, 22:36:56 pm Wow, that's what I was actually thinking about! Almost all of us (11) have a pair of DRLA on their engines (1600-2400), so there is a wide choice to check which ones would suit best :) to make top end power up around 5500-6000 I would say 28mm's on 1300cc Title: Re: max power from very small cc on a strict budget Post by: Zach Gomulka on November 26, 2008, 23:59:31 pm When I come across a couple nickels to rub together, I'm going to rebuild the top end on my GTV, extract as much power as I can without splitting the case, and keep it period EMPI correct. The motor is the original 1600 dual port, this is the plan...
Slip in 88's (I know they suck, but if they give me 10k miles I'm ok with that. I just want to have a little fun here, and buy a little time to build a 5 speed before I build the 88x82 engine ;)). That will increase displacement to 1679cc, forged pistons will be lighter, and it will allow the valves to be unshrouded for better breathing. Also it will bump the compression ratio a bit. Some mild head work (the step will be machined out of the chambers for better squish, and more compression. 8:1 max), with single HD springs, and original EMPI 1.4:1 rockers- lift will increase from .330" to about .420". HD aluminium pushrods, Berg lash caps, ect. Kennedy Stage 1 aluminium pressure plate (saves 3lbs), and I'll drill the crank and flywheel for 8 dowels so everything stays together. 1 3/8" merge header with heater boxes (the boxes wont have the aluminium heat sinks, but it will save quite a bit of weight), and a custom EMPI-esque 3 1/2" diameter, 2" core glass pack muffler, 4 bolt flange. Dual Solex 40P11's on TALL EMPI manifolds. 32mm venturies. Velocity stacks 8) I'll also add an original EMPI deep sump, a type 4 oil cooler, and an air intake ring from a FI fanshroud to keep the temps down. Original EMPI valve covers, and a few other odds and ends. I hope all that will break me deep into the 17's (don't laugh!!) through 3 gears, and with a 5 speed (using 4 in the quarter mile) high 16's might be possible. Title: Re: max power from very small cc on a strict budget Post by: Bewitched666 on November 27, 2008, 08:35:36 am Displacement will be 1300cc?
Swap to 1600 cilinders,add a w110 cam in it,port the heads,standard rockers with solidshafts,009 dizzy,up the cr to 9 and fly away ;D Title: Re: max power from very small cc on a strict budget Post by: Ohio Tom (DdK) on November 27, 2008, 22:18:26 pm many years ago I built a 1600 for a backup drag motor.
everything was useds. I had an old DMS crank (.020" under) to start with. I fly cut the heads to get the C/R up nice and high. Had to trim off the first fin of the heads. Did a nice Port/polish job to the stock valved heads. Multi angle valve job and some other trick. (see my article at Cal-look.com tech section). Used W-125 cam I lightend the pistons and rods as much as possible. Topped off with as pair of 44 IDF's. It was a totall dogg under 4,000rpm. But after that it really woke up alot.. Ran 15.30's in my almost full weight Superbeetle (at that time). I was totally happy with it. Later I upped the displacement to 1755cc, leaving everything else the same. Ran mid 14's then... Title: Re: max power from very small cc on a strict budget Post by: rebel on December 11, 2008, 00:01:41 am many years ago I built a 1600 for a backup drag motor. everything was useds. I had an old DMS crank (.020" under) to start with. I fly cut the heads to get the C/R up nice and high. Had to trim off the first fin of the heads. Did a nice Port/polish job to the stock valved heads. Multi angle valve job and some other trick. (see my article at Cal-look.com tech section). Used W-125 cam I lightend the pistons and rods as much as possible. Topped off with as pair of 44 IDF's. It was a totall dogg under 4,000rpm. But after that it really woke up alot.. Ran 15.30's in my almost full weight Superbeetle (at that time). I was totally happy with it. Later I upped the displacement to 1755cc, leaving everything else the same. Ran mid 14's then... Very intersting, Tom! What did you do to lighten the pistons? What part of a piston is safe to remove material to make them weigh the least possible and prevent them from breakage? What venturi size did you run in the 1600 project? Was it in any way possible to drive 'araund'? I mean drivablity, overheating problems... hat kind of power could it make? Title: Re: max power from very small cc on a strict budget Post by: Bewitched666 on December 11, 2008, 08:16:27 am Build a 1700cc engine
Title: Re: max power from very small cc on a strict budget Post by: rebel on December 11, 2008, 20:09:17 pm I know there's no replacement for displacement, but the goal is set a little different.
One of possible reasons to stay below 1600cc is an attempt to run in a so called 'Mini Plus' drag class (local) which restricts the displacement to N/A 1550cc and RWD cars only. I don't know if anybody will actually try to do it, but it could be really interesting challenge. There's not so many cars to compete with :) Besides It's very intersting thing to think about, dont' you think guys? :) Title: Re: max power from very small cc on a strict budget Post by: Bewitched666 on December 11, 2008, 20:12:45 pm 1600cc
c/w crank or balanced stock crank 40x35.5 round cnc ports 40mm dells w120 or w125 straight cuts full flow 1.5 inch exhaust cr set at 9.5 12 pound flywheel and a good gearbox 8) Title: Re: max power from very small cc on a strict budget Post by: Zach Gomulka on December 11, 2008, 22:32:04 pm One of possible reasons to stay below 1600cc is an attempt to run in a so called 'Mini Plus' drag class (local) which restricts the displacement to N/A 1550cc... Well in that case a 1600 is already over the limit (1585cc)! |