Lotus Elan

Experience with SAS head?

PostPost by: 1owner69Elan » Thu Jul 16, 2015 7:30 am

I am about to pull the trigger on a new head for my 69 S4 SE Elan (federal/Stromberg). I am the original owner of the car and picked the car up at the factory in July 1969. The car has then spent the last 45+ years in California. Car has zero rust, original paint, original interior, but has been sitting for last 13 years because of a failed water pump. I finally have the time to give the car some attention.
I originally was going to just do the required repairs to get it back on the road. But things have escalated.

One thing that always bothered me was that my timing was such that my Elan came with the emission controlled Strombergs. I now have decided to make a jump to a new weber head. Car is now exempt from emissions so can be modified at will.

I am about to pull the trigger and import a new SAS head to California as the centerpiece of creating an updated 1700 cc stroked weber engine. This is to be orchestrated by a long time twincam engine builder and lotus champion racer. The car is intended for street use not race. So torque and not just high rpm hp is a goal.
The spec on the head is for "street" ports of 1.30 intake and 1.25 exhaust. Intake valve of 1.625 and exhaust of 1.40. The valve sizes seem to me to be "race" spec and large.
Would be interested to know if anyone else has experience with a SAS remanufactured head in this configuration and what kind of results did you get? Intend on using weber 40's. Cams not chosen yet.
Be interested in any advice on the rebuild.
Note that I am keeping the car original in most respects. Adding alternator and cv joints, proper exhaust headers.
'69 Elan S4 SE
Street 181 BHP
Original owner
1owner69Elan
Fourth Gear
Fourth Gear
 
Posts: 772
Joined: 16 Jun 2015
Location: Napa, California

PostPost by: CBUEB1771 » Fri Jul 17, 2015 1:09 pm

I see you have not gotten any response. My personal view is to avoid the SAS head because they run the cams directly in the machined bores and not with replaceable bearings. That is OK with a completely modern vehicle with sophisticated engine temperature control. I think it is a very risky approach for an Elan.
Russ Newton
Elan +2S (1971)
Elite S2 (1962)
User avatar
CBUEB1771
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1684
Joined: 09 Nov 2006
Location: Boston, Massachusetts USA

PostPost by: billwill » Fri Jul 17, 2015 2:05 pm

See my topics linked below.

I am VERY pleased with my SAS head.

Image


lotus-elan-f19/getting-ogu-roadworthy-again-t26101.html?hilit=new%20head

lotus-twincam-f39/clay-test-checking-clearance-between-valves-pistons-t26441.html?hilit=%20new%20head

The fact that the cams don't have additional bearing material is not really an issue because the head material is a modern alloy not the original type.

Heck, their main output of these heads is for RACING purposes. There are many of these heads out there in race engines.

In the unlikely event of the cam bearing surfaces getting worn or damaged the head could be line- bored at that time in the far future (there will obviously still be plenty of metal present)and THEN bearing shells could be fitted.
Bill Williams

36/6725 S3 Coupe OGU108E Yellow over Black.
billwill
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 4717
Joined: 19 Apr 2008
Location: London UK

PostPost by: steve lyle » Fri Jul 17, 2015 5:51 pm

Just curious, did you consider converting your head to Webers, via John McCoy at Omnitech or similar, vs a new head? What swayed you to the latter?
Steve Lyle
1972 Elan Sprint 0248k @ https://www.mgexp.com/registry/1972-Lot ... 48K.30245/
1972 MGB Roadster @ https://www.mgexp.com/registry/1972-MG- ... 842G.4498/
2007 BMW 335i Coupe
User avatar
steve lyle
Second Gear
Second Gear
 
Posts: 153
Joined: 15 Jun 2015
Location: Tulsa, OK USA

PostPost by: marklowe » Fri Jul 17, 2015 6:17 pm

I bought a used head from Bob Yarwood a few years ago, I visited him at his home workshop. He showed me around his store room and he had several used heads for me to choose from, he also had a stack of new heads that he used for building race engines that he told me were far superior to the original heads due to the modern casting process. He also told me that he imported the new heads from the USA.

Are home grown new heads available now in the USA? I would imagine that they would be cheaper than importing one from the UK.
User avatar
marklowe
Second Gear
Second Gear
 
Posts: 91
Joined: 08 Feb 2007
Location: Stoke-on-Trent

PostPost by: billwill » Fri Jul 17, 2015 9:54 pm

>He also told me that he imported the new heads from the USA.

Should that be UK ?
Bill Williams

36/6725 S3 Coupe OGU108E Yellow over Black.
billwill
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 4717
Joined: 19 Apr 2008
Location: London UK

PostPost by: CBUEB1771 » Fri Jul 17, 2015 10:11 pm

marklowe wrote:Are home grown new heads available now in the USA? I would imagine that they would be cheaper than importing one from the UK.


Yes, new Weber cylinder heads are being manufactured in the US and available through Dave Bean Engineering. These have been discussed amply here, for example the thread started by bill308:
elan-mods-f31/request-for-feedback-new-engine-t30730.html
Unfortunately these cylinder heads are only being cast with very large inlet tracts. Before Dave Bean took over the product they were also available with standard inlet tract sizes. These use the normal replaceable cam bearings. There is a lot more that just using a modern alloy to make elimination of the cam bearings a rational decision. I believe the new heads produced in the UK by QED retain the cam bearings.
Russ Newton
Elan +2S (1971)
Elite S2 (1962)
User avatar
CBUEB1771
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1684
Joined: 09 Nov 2006
Location: Boston, Massachusetts USA

PostPost by: 1owner69Elan » Sat Jul 18, 2015 3:02 am

Thanks to all for the various responses:

Responding to the various issues raised (not necessarily in order) with information that I have gathered over the past several months speaking in the US with several top twin cam engine builders, Lotus owners, Dave Bean Engineering, etc. :

1. The Dave Bean head, by their own admission, is really only suitable for racing applications as they have a very large inlet port (1.40 in). This works well for racing and for example with very large displacement engines (for example Jay Leno's 26R variant that has in excess of 2 liters - he has a DBE head). Some top-notch twin cam engine builders in the US also feel the currently available Dave Bean head is unsuitable for the street.

2. The Dave Bean and SAS heads do not have cam bearings. The QED head does. The Burton Power head (UK) with no cam bearings appears to me to be the SAS head in actuality but SAS would not confirm that.

3. The alloy used on the SAS heads by all accounts is very hard and is not vulnerable to wear problems - I didn't get any reports from SAS users (mostly racers) of such wear - they enjoy the convenience of no cam bushings. Experience by engine builders machining the SAS heads in the US report the alloy to be rather hard (wears out their tooling faster).

4. I seriously considered the McCoy conversion of my existing Stromberg head. But this is not an inexpensive course of action either - and at the end of the day you still have a base cylinder head that is almost 50 years old - although mine, being the original owner, I know is in excellent condition. I know there may be certain advantages for the McCoy over an original Weber head for porting because of better access but I think this advantage doesn't exist for the new castings. Given a similar price for the McCoy head and the new casting, I chose the new casting which while not truly "original" retains the original Weber head character, is an integrated head in modern materials and including good baseline porting. The other big problem for me was that the turnaround for a McCoy head could be quite long (more than a year reported by some McCoy customers that I spoke with - though they were quite pleased with the end result).

Thus, my gravitating to the SAS head. I really haven't yet seen any negative reports on its use. I did get some complaints that SAS may not strictly adhere to the specified customer specs in their order, arbitrarily providing something slightly different. This was related to an order a number of years back and may not be applicable any more - or a one off issue with a particular customer. But no issues with quality, robustness, or performance.

My UK colleagues that deal with the MOT might be amused by the following:

In anticipation of getting my car back on the road in the near future, I just re-registered my 69 Elan even though the engine and transmission are out of the car at the moment. I haven't driven the car since 2002 (failed water pump) and for the past 13 years failed to inform the DMV (California Department of Motor Vehicles) on its "non-operation". As a result, the DMV interprets my new registration as if the car has been running around on the road for the last 13 years with no legal registration. As such, I was forced to pay for 13 years of past registration and penalties. A tidy sum - though I was prepared for this - paying for my past laziness. If I had simply filed the non-operation paperwork the cost would have been about 5% of what I ultimately had to pay now.

The part that you may find amusing is that in California we have no equivalent of an MOT inspection. Such a safety and roadworthiness inspection process went out with governmental budget cuts decades ago. As such, we can have all manner of cars and "buckets of bolts" running around our roads with nary a care if they are safe or not. Faulty brakes, steering, etc be damned. Interestingly I have an inspection sticker dated 1972 that I have kept on my windscreen. An historical oddity that very few remember.

So, as is patently ridiculous, I registered my Elan that hasn't been driven in over 13 years and actually has no engine/transmission at the moment (and I haven't even yet gone through the brakes, etc - which of course I will do before driving). Got a new license sticker valid into 2016. Also ordered a legacy (old style) 1960's personalized plate ("6T9 ELAN") at the same time. All the DMV wanted was for me to pay my expensive fee and to show my proof of insurance coverage - no other concerns re roadworthiness. So I can drive whatever condition vehicle I want, just be sure that there is insurance to pay up when something goes awry. Freedom or foolishness in the good ol' US of A?
'69 Elan S4 SE
Street 181 BHP
Original owner
1owner69Elan
Fourth Gear
Fourth Gear
 
Posts: 772
Joined: 16 Jun 2015
Location: Napa, California

PostPost by: CBUEB1771 » Sat Jul 18, 2015 4:07 am

1owner69Elan wrote:2. The Dave Bean and SAS heads do not have cam bearings. The QED head does. The Burton Power head (UK) with no cam bearings appears to me to be the SAS head in actuality but SAS would not confirm that.


This must be another change to the US-made heads since Dave Bean took over. I saw two of the early heads and they were machined to accept the standard replaceable bearings.
Russ Newton
Elan +2S (1971)
Elite S2 (1962)
User avatar
CBUEB1771
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1684
Joined: 09 Nov 2006
Location: Boston, Massachusetts USA

PostPost by: 1owner69Elan » Sat Jul 18, 2015 4:43 am

Yes. Speaking with DBE this was a conscious decision to go without bearings. Heads are now made at Buddy Bar Casting, Southern California.

The DBE heads also typically have 10mm spark plugs. This allows more room for the engine builder to use bigger valves and throat areas.
'69 Elan S4 SE
Street 181 BHP
Original owner
1owner69Elan
Fourth Gear
Fourth Gear
 
Posts: 772
Joined: 16 Jun 2015
Location: Napa, California

PostPost by: ianthomson72 » Thu Jul 23, 2015 12:45 pm

Hi all,

It seems to be modern practice to run cams and tappet sleeves directly in the head. My triumph 900cc bike was designed in the early 90s , it runs quite happily to 9000rpm and has done 50,000 miles to date without signs of wear. This engine is quite low revving by bike standards, some of the sports 600s rev to 15,000 and they all run without bearings or sleeves. Metallurgy seems to have advanced hugely since the late 50s when our engines were designed
A twin cam head made out of a modern alloy would seem to be ideal if you can afford it .
Good luck with the project.
Regards
ianthomson72
First Gear
First Gear
 
Posts: 20
Joined: 27 Feb 2011

PostPost by: rgh0 » Thu Jul 23, 2015 1:28 pm

The LM25 alloy that the SAS heads are cast from is not that different from what Lotus used. They used LM8 alloy in the early heads and i believe LM25 which is a similar but newer alloy in the later (post about 1970?) heads.

The real change has been a realization from engine designers that the direct head alloy casting is suitable for running cams in. Modern casting to get good quality metal of the right hardness and machining techniques to get the bore clearances accurate enough and modern oils to lubricate it have also helped

cheers
Rohan
User avatar
rgh0
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 7487
Joined: 22 Sep 2003
Location: Melbourne, Australia

PostPost by: 1owner69Elan » Thu Jul 23, 2015 7:28 pm

Head is ordered . 4 to 6 weeks production time. Will be pairing with Weber 40's to be ordered.

On top of base cost (but no VAT) have shipping and import duty in U.S. to contend with.

Meet in one month with engine builder to work out rest of scope of work and needed parts. He's tied up in the historic racing season til then. (Chevron B-36 and March 73S).

Former 3 time U.S. national champ and mechanic in a 26R Elan.
'69 Elan S4 SE
Street 181 BHP
Original owner
1owner69Elan
Fourth Gear
Fourth Gear
 
Posts: 772
Joined: 16 Jun 2015
Location: Napa, California

PostPost by: billwill » Thu Jul 23, 2015 7:36 pm

I presume you mean that you ordered an SAS head?

Some other heads were mentioned in this topic.
Bill Williams

36/6725 S3 Coupe OGU108E Yellow over Black.
billwill
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 4717
Joined: 19 Apr 2008
Location: London UK

PostPost by: 1owner69Elan » Thu Jul 23, 2015 7:56 pm

Yes. I did order the SAS head.

In street porting spec.

My engine builder further specified that sufficient material be left to allow guides to be customized for the slight valve variations found in American manufactured valves. Needless to say builder is a no compromise perfectionist.
'69 Elan S4 SE
Street 181 BHP
Original owner
1owner69Elan
Fourth Gear
Fourth Gear
 
Posts: 772
Joined: 16 Jun 2015
Location: Napa, California
Next

Total Online:

Users browsing this forum: No registered users and 11 guests