TheSamba.com :: View topic - Impressive small displacement combo (chassis dyno eval)

Sun Jan 02, 2011 12:07 pm

I'm very happy with the FK-41 in my 87x74 combo, and the FK-42 in my 2017 combo. Very great cams!

Sun Jan 02, 2011 1:36 pm

Bashr52 wrote: I'm very happy with the FK-41 in my 87x74 combo, and the FK-42 in my 2017 combo. Very great cams! Have to agree there....they are my 2 top cam choices for anything that is on the street and uses 1.4's.

I had a PM from a member here who wanted to know why I never use the older 87 and 89 Engle's (he had an 87 in his engine). I gave him a detailed analysis based on his engine and heads that clearly showed how each cam choice peaked the HP at the same RPM, the same HP and torque due to the heads dominating the high speed flow and based on that the rest of how the engine ran dealt with all the area below the curves which has to do with valve acceleration. Far too much to go into here. After all that, the best cam once again was the 42 even though I ran all the way from the 41 thru 45 and the 87 for him.

You really need heads beyond Super-Flo's or CE2000's to need any more cam than a 42 and I've never built anything with more head than that yet...but I'd like to.

RC

Fri Jan 07, 2011 9:25 pm

Jake,

What springs did you run with this combo, single HD or dual?

Thanks....

Sat Jan 08, 2011 12:12 pm

Singles.. Its not going to rev over 5K on the street and I didn't want the added oil temps that I find so common with dual springs..

Sat Jan 22, 2011 7:17 pm

MPG results? What compression do you think would work best with this combo?

Sat Jan 22, 2011 7:37 pm

I haven't been driving it... Have had too many M96 powered cars to test lately.
This one is working fine at 9.5:1

Sat Jan 29, 2011 9:03 pm

How would this combo be affected with Ported Heads and 40mm x 35.5mm Valves?

Sat Jan 29, 2011 9:40 pm

yeoldeluke wrote: How would this combo be affected with Ported Heads and 40mm x 35.5mm Valves?
It would probably lose throttle response, lose torque and make power at an RPM that would require dual springs.

All of those were on my list of "can't stands" for this engine. It also probably would not have liked the single carb nearly as much.

I can't think of a time in the past decade or so when I have been able to prove that "bigger" was actually better.

Fri Feb 25, 2011 4:42 pm

pardon me if this is a dumb question, but: does this engine use only the stock oiling system? or has that been upgraded?

didn't see any upgrading mentioned in the recipe, but perhaps that's taken for granted?

thanks

Fri Feb 25, 2011 7:11 pm

It has been only upgraded to full flow.. No other changes.

The engine is not making me happy in this application. This engine is offering a true challenge in trying to optimize it for cool running.

It has exceptionally high CHT and oil temperature as well. The issue is not the engine, as much as the engine's inability to push the heavy superbeetle with gearing developed for a TIV engine. This vehicle previously had a 2270TIV in it, before I bought it.. The old owner needed cash so he parted the engine out and sold me the car engineless...

The engine runs cool as long as it doesn't use 4th gear.. As soon as the car is shifted into 4th the CHT skyrockets to over 400F and after a few minutes of that the oil becomes overheated, even though the RPM is so low.

We installed a 356 top pulley to speed up the fan, which was good for 50F, but still not enough.I optimized the timing, went up and down from that point and also altered enrichment, no dice.

The engine runs great, but this gearing is thermally overloading this small engine with its limited T1 cooling capability. I want to keep the heaterboxes on it, so I do not want to install a DTM, which also will not work with the single Dellorto 40.

The engine is a misconfiguration for this car and application with 25.75" tires and a 3.88 ring and pinion with a .82 4th gear. At this point we call it "The Thermal Reactor".

The engine has not seen any damage from the elevated temps and it hasn't even been hot enough, long enough to tighten the valves up. I'll be selling the engine... The engine hasn't ever detonated once with audible ping.. The car is going to be used for the next generation of development.

I have to say that I LOVE to drive this engine, it is so fun and so responsive to be so little.. Sorry it can't meet my expectations for it.. I drove it home last weekend and thats the first time in 5 years that I have had to shift down to climb the 6% grade that I ascend everyday thats 3 miles long...

I have seen this before.. too much engine load building too much heat and not enough fan speed to cool it down.. Thats when a "freeway flyer" becomes a "freeway FRYER!"... Been there before, but I guess I have been spoild by TIV engines that will pull this gearing and never see a 350F CHT and more than a 200 OT.. Thats what the 9.5:1, 165HP engine that was in the car before was able to do with this same gearing..

I forgot what overheating problems were, welcome back to the world of the smallblock I suppose..

Sat Feb 26, 2011 9:30 am

Jake,

thank you for posting your thoughts on this. I always learn from your posts.

doug

Tue Mar 01, 2011 9:19 am

Received the break in oil sample.. Not Happy at all with it.
Considering this was oil that had only one mile of street time on it and 7 chassis dyno pulls these levels of wear metals and fuel dilution are not acceptable. The engine is not running rich, so it is clear that it has poor ring seal as well.

Iron levels are higher than what I see with these same oils after both engine dyno and chassis dyno time coupled to 500 miles of street driving. I have another sample submitted now of non-break in oil (VSO 30) so we'll see how it looks.

This illustrates exactly why we do this level of evaluation, its not always positive results that we gather. Not impressed.[/img]

Fri Mar 04, 2011 7:48 pm

Jake. how will this motor run in a standard bug with stock running gear and 205/75r15's
how much are you thinking of selling the thermo reactor for?

Fri Mar 04, 2011 8:00 pm

Did you use plain cast iron rings?

Or is that (gasp) the lifters?!

Or just run it till whatever it is wears itself clean to bits, in the TRADITIONAL method, of engine testing!

Fri Mar 04, 2011 10:42 pm

In the first post, you said you would recommend this set-up for anyone wanting a cheap torquer combo. In a subsequent post you addressed the issue of it being hard on lifter bores and not having a quiet valve train. Is there a way around those two issues?

Thanks,

Chuey

Sat Mar 05, 2011 10:21 pm

The engine isn't as impressive as it was.. I am doing some more research work with it and I can't sell it without it being a liability.. Plus I need to see what story is with future oil samples.
I can't sell any engine if it's not 100%. I am considering blowing it sky high at our show here in June, I need a charity engine blow engine anyway.

Wed Mar 09, 2011 9:21 pm

I take it this combo would not work too well in a hot climate? Any ideas what would improve the engine?

Wed Mar 09, 2011 9:28 pm

Jake Raby wrote: The engine isn't as impressive as it was.. I am doing some more research work with it and I can't sell it without it being a liability.. Plus I need to see what story is with future oil samples.
I can't sell any engine if it's not 100%. I am considering blowing it sky high at our show here in June, I need a charity engine blow engine anyway.

Does that mean you are rescinding your recommendation of this engine configuration as a good one?

Chuey

Thu Mar 10, 2011 7:07 pm

Quote: Jake Raby wrote:
The engine isn't as impressive as it was.. I am doing some more research work with it and I can't sell it without it being a liability.. Plus I need to see what story is with future oil samples.
I can't sell any engine if it's not 100%. I am considering blowing it sky high at our show here in June, I need a charity engine blow engine anyway.

or you can donate it to my wifes standard 71 daily driver!!!! lmao in my dreams especially since your in georgia and im in Nevada! would that be a tax write off?........ lol

Fri Mar 11, 2011 3:15 pm

3.88 and an .082...

Not surprising that it's getting hot.

Do you plan on putting a stock trans in for testing purposes?
Maybe just find some short tires?

You might have guessed that it would fry,
It's not a T4, afterall...