Hello! Log in or Register   |  Help  |  Donate  |  Buy Shirts  See all banner ads | Advertise on TheSamba.com  
TheSamba.com
 
Re-Sweep the Floor 1679cc- Heads/Cam/Exhaust? More Top End
Page: 1, 2, 3, 4, 5, 6, 7  Next
Forum Index -> Performance/Engines/Transmissions Share: Facebook Twitter
Reply to topic
Print View
Quick sort: Show newest posts on top | Show oldest posts on top View previous topic :: View next topic  
Author Message
theastronaut
Samba Member


Joined: November 19, 2007
Posts: 1533
Location: Anderson, SC
theastronaut is offline 

PostPosted: Mon Oct 06, 2014 2:00 pm    Post subject: Re-Sweep the Floor 1679cc- Heads/Cam/Exhaust? More Top End Reply with quote

The "sweep the floor" 1679 broke a valve spring last weekend so it's time to upgrade. It didn't hurt the piston so I'll keep the bottom end like it is. Has a DPR crank and forged Mahles. I'll probably add AA's I-beam rods with ARP bolts for insurance.

I don't like the instant torque of the FK41 and stock heads- too touchy to drive smoothly, plus they run out of steam way too early for my 4.37 trans. I'd like a redline of 7500 and for it to make power to atleast 7000-7200.

I need heads and exhaust. I have a Webcam 86B that I could use, or have been looking at the FK44. I'm leaning towards DRD/AC.net L3 heads for it and possibly doing a little work to the ports. Are there any other suitable heads for a highish RPM 1679cc? CB has discontinued their CNC ported Los Panchitos heads. What about Steve Tims Super Stock heads?

Compression would be 9.5-10 to 1.

I'll be getting rid of the Vintage Speed muffler for a sidewinder style header/muffler. I know 1 5/8" wouldn't be ideal but I've seen a couple post on here from respected builders stating that bigger exhaust didn't kill low end torque like it should have on that small of a motor. I could re-use it on my 2276 eventually. I don't want to spend a ton on exhaust just for the 1679 if I don't have to. Plus AA is currently out of their 1.5" sidewinder systems. I need the ground clearance; it's lowered so I can't run a typical merged header.


Combo would be something like:

Car is a '64 type 1, 4.37 trans. Stock weight, 1640 pounds. 165 tires.

Thick wall forged Mahle 88's
DPR counterweighted 69 crank
86b or FK44 cam
1.4 Rockers
DRD/AC.net L3 heads- mild porting?
Dual Dellorto 36 DRLA's, currently have 30 vents but could go up to 32-33
AA performance 1 5/8" Stainless Sidewinder.
_________________
Strive for perfection in everything. Take the best that exist and make it better. If it doesn't exist, create it. Accept nothing nearly right or good enough."
-Sir Henry Royce, co-founder of Rolls-Royce

'64 Beetle Sunroof OG Bahama Blue
'63 Beetle Vert
'66 Beetle
'88 Festiva L
'89 Festiva L
'64 Chevy C10
'66 Chevy C10
Back to top
View user's profile Send private message Instagram Gallery Classifieds Feedback
Matthew
Samba Member


Joined: January 29, 2004
Posts: 1549
Location: Fort Pierce, FL
Matthew is offline 

PostPosted: Mon Oct 06, 2014 3:39 pm    Post subject: Reply with quote

I think both of those cams are too much for the combo you are proposing. The L5 heads would be closer to the Los panchitos. Tims stage one should be similar as well.

If you go with the bigger (L5) heads, the 86B should be ok, but I think the carbs will be too small.
_________________
1965 Beetle sedan
Click to view image
Back to top
View user's profile Send private message Send e-mail Gallery Classifieds Feedback
MURZI
Samba Member


Joined: August 25, 2005
Posts: 5017
Location: Madisonville, La
MURZI is offline 

PostPosted: Mon Oct 06, 2014 4:22 pm    Post subject: Reply with quote

Leave the cam. Shove some 40x35 049 revmasters on there.
_________________
62 vert
2276
Timís welded heads
45 Dells
A1 sidewinder
Fk44 cam
Back to top
View user's profile Send private message Gallery Classifieds Feedback
modok
Samba Member


Joined: October 30, 2009
Posts: 21425
Location: Colorado Springs
modok is offline 

PostPosted: Mon Oct 06, 2014 5:08 pm    Post subject: Reply with quote

It's a matter of cam. Milder cams you can use to0-big exhaust, but once you have a lot more duration and overlap you need the right size to CONTROL flow or else it may have bonkers reversion!!

Mightymouse ran 7k rpm with stock heaterboxes. Ask that guy Very Happy

IMO valve should not be bigger than your throttle. 37x32 is good size for those. 10-1 compression and a 86b!!!!!
Back to top
View user's profile Send private message Gallery Classifieds Feedback
GTV
Samba Member


Joined: March 27, 2004
Posts: 2081
Location: Si'ahl
GTV is offline 

PostPosted: Mon Oct 06, 2014 6:46 pm    Post subject: Reply with quote

Need more carb.
_________________
EMPI Power Rules!
Back to top
View user's profile Send private message Gallery Classifieds Feedback
youngnstudly
Samba Member


Joined: October 21, 2005
Posts: 828
Location: Whine Country (SF Bay area)
youngnstudly is offline 

PostPosted: Mon Oct 06, 2014 7:15 pm    Post subject: Reply with quote

I don't see much point in trying to build a high horsepower 7,000 RPM small engine when you're already doing a 2276cc. Let the "big engine" wind up to 7 grand and make all the horsepower. I'd have the stock heads on your small engine ported and I'd leave everything else (that isn't broken) alone. Keep it simple, and don't mix parts back and forth between engines.

Unless your heads need major work, I wouldn't even waste time on bigger valved heads...or a bigger cam...or bigger exhaust. My minimal experience in over-camming smaller displacement engines didn't leave a good impression on me, and it's easy to do with limited displacement unless you start upgrading everything. At that point, where does the madness end? Shocked Laughing
_________________
The economy is in a state of disaster, we have NO time for common sense!
Back to top
View user's profile Send private message Gallery Classifieds Feedback
theastronaut
Samba Member


Joined: November 19, 2007
Posts: 1533
Location: Anderson, SC
theastronaut is offline 

PostPosted: Mon Oct 06, 2014 8:06 pm    Post subject: Reply with quote

GTV wrote:
Need more carb.


I don't think the carbs are too small, especially if I go up on the venturi size? I found this post in another thread:

Source: CB Performance 1991 catalog- no flow specs or venturi sizes
I assume these numbers are @28" H2O per venturi

Dell'Orto 48mm DRLA 388.5cfm
Weber 48mm IDA 372.1cfm
Dell'Orto 45mm DRLA 329.3cfm
Weber 44mm IDF 292.3cfm
Dell'Orto 40mm DRLA 266.4cfm
Weber 40mm IDF 212.8cfc
Dell'Orto 36mm 205.8cfm


I doubt the heads I'll end up with will flow over 150 cfm... So why would I need bigger carbs if my 36's flow 205 cfm? Mine are from CB so I assume these flow test would have had the same venturi size that they shipped with.

Also, a 1679cc is only 6 ci smaller than a 1776 and about 9-10 ci smaller than an 1835. Looking at it in CI instead of CC makes the difference seem way smaller than everybody makes it out to be. And makes the difference in carb sizing/flow seem like it would matter less since there isn't that much size difference in CI. If we can make a streetable 200hp 2276:2332 (139/142 CI) that makes about 1.4 hp/ci than why can't a 1679 (102 ci) make 1.4 hp/ci (about 140 hp) and still be driveable?

Seems to me that smaller motors could/should be making more power but the readily available heads for smaller cc engines aren't as highly developed as they are for bigger motors.


youngnstudly wrote:
I don't see much point in trying to build a high horsepower 7,000 RPM small engine when you're already doing a 2276cc. Let the "big engine" wind up to 7 grand and make all the horsepower. I'd have the stock heads on your small engine ported and I'd leave everything else (that isn't broken) alone. Keep it simple, and don't mix parts back and forth between engines.

Unless your heads need major work, I wouldn't even waste time on bigger valved heads...or a bigger cam...or bigger exhaust. My minimal experience in over-camming smaller displacement engines didn't leave a good impression on me, and it's easy to do with limited displacement unless you start upgrading everything. At that point, where does the madness end? Shocked Laughing


I want to do it because it's apart to fix it and I've always wanted to see what could be done with a smaller motor, short gears, and a early/lighter car. I need block work or another block for the 2276, and then a built trans once it's ready to go in. Easily $4,000+ to get the 2276 in the car. A little motor shouldn't make enough torque to hurt my current transmission if I don't abuse it badly.
_________________
Strive for perfection in everything. Take the best that exist and make it better. If it doesn't exist, create it. Accept nothing nearly right or good enough."
-Sir Henry Royce, co-founder of Rolls-Royce

'64 Beetle Sunroof OG Bahama Blue
'63 Beetle Vert
'66 Beetle
'88 Festiva L
'89 Festiva L
'64 Chevy C10
'66 Chevy C10
Back to top
View user's profile Send private message Instagram Gallery Classifieds Feedback
bugguy1967
Samba Member


Joined: January 16, 2008
Posts: 3584
Location: Los Angeles, CA 90016
bugguy1967 is offline 

PostPosted: Mon Oct 06, 2014 9:51 pm    Post subject: Reply with quote

theastronaut wrote:
GTV wrote:
Need more carb.


I don't think the carbs are too small, especially if I go up on the venturi size? I found this post in another thread:

Source: CB Performance 1991 catalog- no flow specs or venturi sizes
I assume these numbers are @28" H2O per venturi

Dell'Orto 48mm DRLA 388.5cfm
Weber 48mm IDA 372.1cfm
Dell'Orto 45mm DRLA 329.3cfm
Weber 44mm IDF 292.3cfm
Dell'Orto 40mm DRLA 266.4cfm
Weber 40mm IDF 212.8cfc
Dell'Orto 36mm 205.8cfm


I doubt the heads I'll end up with will flow over 150 cfm... So why would I need bigger carbs if my 36's flow 205 cfm? Mine are from CB so I assume these flow test would have had the same venturi size that they shipped with.

Also, a 1679cc is only 6 ci smaller than a 1776 and about 9-10 ci smaller than an 1835. Looking at it in CI instead of CC makes the difference seem way smaller than everybody makes it out to be. And makes the difference in carb sizing/flow seem like it would matter less since there isn't that much size difference in CI. If we can make a streetable 200hp 2276:2332 (139/142 CI) that makes about 1.4 hp/ci than why can't a 1679 (102 ci) make 1.4 hp/ci (about 140 hp) and still be driveable?

Seems to me that smaller motors could/should be making more power but the readily available heads for smaller cc engines aren't as highly developed as they are for bigger motors.


youngnstudly wrote:
I don't see much point in trying to build a high horsepower 7,000 RPM small engine when you're already doing a 2276cc. Let the "big engine" wind up to 7 grand and make all the horsepower. I'd have the stock heads on your small engine ported and I'd leave everything else (that isn't broken) alone. Keep it simple, and don't mix parts back and forth between engines.

Unless your heads need major work, I wouldn't even waste time on bigger valved heads...or a bigger cam...or bigger exhaust. My minimal experience in over-camming smaller displacement engines didn't leave a good impression on me, and it's easy to do with limited displacement unless you start upgrading everything. At that point, where does the madness end? Shocked Laughing


I want to do it because it's apart to fix it and I've always wanted to see what could be done with a smaller motor, short gears, and a early/lighter car. I need block work or another block for the 2276, and then a built trans once it's ready to go in. Easily $4,000+ to get the 2276 in the car. A little motor shouldn't make enough torque to hurt my current transmission if I don't abuse it badly.


An engine that size that makes 1.4 HP per CI will be a bit soft, but will be driveable. The powerband would be the same between a 1679 and 2332, if the components were working at the same efficiency. The 1679's torque would be much lower than the 2332's though. I guess as long as it makes at least the same torque between idle and 1500 RPM as a 40 horse, it'll move your car decently when you let off the clutch. I'd shoot for peak compression.

Also, I think people underestimate Dell 36s. They come standard with 30 vents and the same throttle shaft thickness as a Weber, which makes them bigger than 40 IDFs out of the box. You might be able to get close to your goal with 33mm vents, if they make them. I also wouldn't hesitate running larger valves than my throttle bore/s. Heck, modified Type 4 engines typically run 36-40mm carburetors with big ass valves.
Back to top
View user's profile Send private message Send e-mail Gallery Classifieds Feedback
esde
Samba Member


Joined: October 20, 2007
Posts: 4246
Location: central rust belt
esde is offline 

PostPosted: Mon Oct 06, 2014 10:08 pm    Post subject: Reply with quote

bugguy1967 wrote:
You might be able to get close to your goal with 33mm vents, if they make them.


I have had 34mm vents in a dell 36 DRLA before, they were from CB
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Bajaman65
Samba Member


Joined: January 16, 2007
Posts: 469
Location: Borrego Springs
Bajaman65 is offline 

PostPosted: Mon Oct 06, 2014 10:14 pm    Post subject: Reply with quote

[quote
Unless your heads need major work, I wouldn't even waste time on bigger valved heads...or a bigger cam...or bigger exhaust. My minimal experience in over-camming smaller displacement engines didn't leave a good impression on me, and it's easy to do with limited displacement unless you start upgrading everything. At that point, where does the madness end? Shocked Laughing[/quote]
I agree 'Stop the Madness' building a little engine that you have to scream around like a 125cc bike is a waste. Just build a big engine and be real happy like the rest of use stroker people. There is NO replacement for Displacement!
Back to top
View user's profile Send private message Gallery Classifieds Feedback
GTV
Samba Member


Joined: March 27, 2004
Posts: 2081
Location: Si'ahl
GTV is offline 

PostPosted: Tue Oct 07, 2014 12:10 am    Post subject: Reply with quote

Go for it! Small motors are fun, especially when you beat up on a 2 liter.

Some good flowing 40x35.5 heads, the 86b will get you there, a nice dose of compression, and yeah bigger carbs... 45 Dells. Do the math, 419.75cc per cylinder to 7,500 rpm theoretically needs a 37mm venturi! The 36's aren't going to pull to 7k+... Why are you against upgrading them? Sell the 36's, find some 45's, you might have $200 in the upgrade, or you might even make some back if you get lucky at a swap meet.
140hp is absolutely possible.
_________________
EMPI Power Rules!
Back to top
View user's profile Send private message Gallery Classifieds Feedback
modok
Samba Member


Joined: October 30, 2009
Posts: 21425
Location: Colorado Springs
modok is offline 

PostPosted: Tue Oct 07, 2014 1:38 am    Post subject: Reply with quote

theastronaut wrote:
GTV wrote:
Need more carb.


I don't think the carbs are too small, especially if I go up on the venturi size? I found this post in another thread:



From the viewpoint of steady state flow it LOOKS like it will work fine. But carburetors also carburate, and the state they do this in isn't steady.

What you need to know:
Venturi should be 75-83% of carb bore size, for larger than this...... and signal begins to be reduced.
Also the venturi is not supposed to be the smallest point in the system, because......well lots of reasons. Carbs don't need to have the airspeed hitting sonic, they don't like it, and you want that point of max airspeed down at the head not in the carb!!!
Back to top
View user's profile Send private message Gallery Classifieds Feedback
MURZI
Samba Member


Joined: August 25, 2005
Posts: 5017
Location: Madisonville, La
MURZI is offline 

PostPosted: Tue Oct 07, 2014 5:27 am    Post subject: Reply with quote

GTV wrote:
Go for it! Small motors are fun, especially when you beat up on a 2 liter.

Some good flowing 40x35.5 heads, the 86b will get you there, a nice dose of compression, and yeah bigger carbs... 45 Dells. Do the math, 419.75cc per cylinder to 7,500 rpm theoretically needs a 37mm venturi! The 36's aren't going to pull to 7k+... Why are you against upgrading them? Sell the 36's, find some 45's, you might have $200 in the upgrade, or you might even make some back if you get lucky at a swap meet.
140hp is absolutely possible.


I just built a 1776 based around the great success of the OP(Raby built combo). 1776, FK41, 049 40x35 revmasters, 1.25 rockers (.492 actual lift) 8.75 compression, .045 deck, 50cc heads, 40 HPMX's with 28 vents. It is a beast!! Despite the low duration, this combo rocks!!! It will rev to 7K easy...easy.... I believe the power is in the heads. These 049's flow nicely and may just be the simple solution.


Link

_________________
62 vert
2276
Timís welded heads
45 Dells
A1 sidewinder
Fk44 cam
Back to top
View user's profile Send private message Gallery Classifieds Feedback
saw2
Samba Member


Joined: November 06, 2008
Posts: 313
Location: nw Oregon
saw2 is offline 

PostPosted: Tue Oct 07, 2014 7:26 am    Post subject: Reply with quote

Murzi,
On your 1776 combo are the 049 Revmasters out of the box or have they been touched up or ported?

Thanks
Back to top
View user's profile Send private message Gallery Classifieds Feedback
MURZI
Samba Member


Joined: August 25, 2005
Posts: 5017
Location: Madisonville, La
MURZI is offline 

PostPosted: Tue Oct 07, 2014 8:17 am    Post subject: Reply with quote

Just flycut and match ported.
_________________
62 vert
2276
Timís welded heads
45 Dells
A1 sidewinder
Fk44 cam
Back to top
View user's profile Send private message Gallery Classifieds Feedback
MURZI
Samba Member


Joined: August 25, 2005
Posts: 5017
Location: Madisonville, La
MURZI is offline 

PostPosted: Tue Oct 07, 2014 8:20 am    Post subject: Reply with quote

MURZI wrote:
Just flycut and match ported.


Image may have been reduced in size. Click image to view fullscreen.

_________________
62 vert
2276
Timís welded heads
45 Dells
A1 sidewinder
Fk44 cam
Back to top
View user's profile Send private message Gallery Classifieds Feedback
[email protected]
Samba Member


Joined: August 03, 2002
Posts: 12592
Location: Salt Lake City, Utah
john@aircooled.net is online now 

PostPosted: Tue Oct 07, 2014 8:47 am    Post subject: Reply with quote

a 35mm intake will stop increasing flow around .450" lift, so why lift the valve to .580? Either go with bigger valves (40mm), or use a low valve lift cam/rocker. Something like an W130 would probably work really well, with a lot of duration and small on the lift. Perfect for what you are doing.

On the "CFM" charts: are those flows per carb or per barrel? See the issue?
_________________
It's just advice, do whatever you want with it!

Please do NOT send me Private Messages through the Samba PM System (I will not see them). Send me an e-mail to john at aircooled dot net

"Like" our Facebook page at
http://www.facebook.com/vwpartsaircoolednet
and get a 5% off code for use on one order for VW Parts ON OUR PARTS STORE WEBSITE, vwparts.aircooled.net
Back to top
View user's profile Send private message Send e-mail Visit poster's website Facebook Gallery Classifieds Feedback
saw2
Samba Member


Joined: November 06, 2008
Posts: 313
Location: nw Oregon
saw2 is offline 

PostPosted: Tue Oct 07, 2014 9:09 am    Post subject: Reply with quote

John,
At ac.net do you guys have a regular non ported version of the 049 Revmaster heads?
Back to top
View user's profile Send private message Gallery Classifieds Feedback
midtravelmidengine
Samba Member


Joined: August 06, 2009
Posts: 861
Location: Riverside, Ca
midtravelmidengine is offline 

PostPosted: Tue Oct 07, 2014 10:07 am    Post subject: Reply with quote

theastronaut wrote:

Seems to me that smaller motors could/should be making more power but the readily available heads for smaller cc engines aren't as highly developed as they are for bigger motors.


Amen to that!!

That is why i started tis discussion ---> http://www.thesamba.com/vw/forum/viewtopic.php?t=580635&postdays=0&postorder=asc&start=0
_________________
modok wrote:
And I know you don't know because if you did you would know the reason for my knowing you didn't.


youngnstudly wrote:
I just wasn't sure if I should recommend the 1/3 race cam, the 1/2 race cam, or the 5/8 race cam instead...guess it depends on how much of the race he wants to lead???
Back to top
View user's profile Send private message Gallery Classifieds Feedback
bugguy1967
Samba Member


Joined: January 16, 2008
Posts: 3584
Location: Los Angeles, CA 90016
bugguy1967 is offline 

PostPosted: Tue Oct 07, 2014 1:12 pm    Post subject: Reply with quote

[email protected] wrote:
a 35mm intake will stop increasing flow around .450" lift, so why lift the valve to .580? Either go with bigger valves (40mm), or use a low valve lift cam/rocker. Something like an W130 would probably work really well, with a lot of duration and small on the lift. Perfect for what you are doing.

On the "CFM" charts: are those flows per carb or per barrel? See the issue?


X2 Astro. I didn't notice that you wanted to use L3s with that combo. Use some 40x35 ported heads.
Back to top
View user's profile Send private message Send e-mail Gallery Classifieds Feedback
Display posts from previous:   
Reply to topic    Forum Index -> Performance/Engines/Transmissions All times are Mountain Standard Time/Pacific Daylight Savings Time
Page: 1, 2, 3, 4, 5, 6, 7  Next
Page 1 of 7

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

About | Help! | Advertise | Donate | Premium Membership | Privacy/Terms of Use | Contact Us | Site Map
Copyright © 1996-2020, Everett Barnes. All Rights Reserved.
Not affiliated with or sponsored by Volkswagen of America | Forum powered by phpBB