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Cal-look/High Performance => Pure racing => Topic started by: Lee.C on February 13, 2007, 02:43:34 am



Title: ideas for my new engine
Post by: Lee.C on February 13, 2007, 02:43:34 am
As a few of you may know i am planning a new project - The 70's Looker  8) and Ive been thinkinking about ENGINES ;D

I want to keep the engine as authentic as I can but still make good power (read very GOOD power ;)) I already have a set of IDA's and a pair of Scat D port heads with 40x37.5 valves and 56cc Chambers they are also cut for 90.5/92's so I am a little limited in the overall sizes I can go for but I have been thinking about a 1968cc but I know there is NO replacement for CC's so I may go up to a 2180cc  :)

The Main questions I have are what are the differences between using a shorter stroke crank and big piston rather than using a long stroke and smaller pistons ??? ??? ???  Do they Rev differently ??? Do they produce power in different ways  ??? is one more reliable than the other  ??? Which is better for all out street racing  ???

I know alot of you guys will just say "just use long stroke a big piston" But I really do want to try and use what was around "Back in the day" and lets face it those guys ran some pretty dam good times

I am not too bothered about overall driveability and motorway/freeway driving won't be to much of a problem either as I plan on running a Berg5 speed

Come on guys give me some cool Old Skool combo's

Also any info on running with a Magneto would also be helpfull - Thanks Guys :)

Oh and some good gear ratios for a 5 speed box if you have time  ;) :)



Title: Re: ideas for my new engine
Post by: alex d on February 13, 2007, 09:28:37 am
oh well, you can't go wrong with a 2180 (if you're gona stroke it, stroke it!), but those 92 cylinders are a litlle thin for my taste


Title: Re: ideas for my new engine
Post by: Fastbrit on February 13, 2007, 10:21:58 am
oh well, you can't go wrong with a 2180 (if you're gona stroke it, stroke it!), but those 92 cylinders are a litlle thin for my taste
That is such an old wife's tale generated by a certain Mr Berg (he didn't invent them, so they didn't work... ). 92s were the mainstay of the performance industry for years. I ran them on my Bus (1835cc) as a tow vehicle for my race car. No problems at all. A friend used to tow his Porsche race car all over Europe behind his 1835cc Bus, too. Thousands of miles without problem. Keep 'em cool and they'll live – but you need to do that with any big-bore set-up anyway. I even used 92s for a season on my turbo race car, without any failures. In fact, the only barrels I ever cracked (once) were 94s.

This is all IMHO of course... :)


Title: Re: ideas for my new engine
Post by: alex d on February 13, 2007, 10:37:33 am
of course they can work, in fact even slip-in 88s can, but you'll agree that 90,5s or even 94s are more forgiving, specially for a novice!



Title: Re: ideas for my new engine
Post by: ESH on February 13, 2007, 12:53:04 pm
If you're looking to make 'very good' power then you'll want to eliminate any weak links and for my money that eliminates the use of a Berg (type1) 5 speed. It is inherently weaker than the 4 speed options out there. There are people out there that have had them live but I recently had to make up my mind on this one and decided against it and that's with a 'conservative' set up power wise. The way around it is either a 'built' box with GT ratios (or higher) or just go margianally shorter than the GT. On the 1/4 a GT doesn't really work that well and you'll never run the potential of your motor also if you do go long ratio you'll want torque so work that in to your engine combo. As for the Magneto, it can definitely be used on the street and would be fine for a once a week 'Saturday Night Special' type set up but probably not so good for a car used more frequently, again I thought about it but in the end decided on a different route though there are a few guys out there that have run them with drivers. I get the impression that you wouldn't mind greater authenticity at the expense of a few more hassles though. :)


Title: Re: ideas for my new engine
Post by: Jon on February 13, 2007, 13:21:48 pm
Why shouldn't a Magneto work on a daily driver?
And any novice should have the carbs adjusted by a professional, with his experience and some safety margins on your side a novice can make anything work. I used a Magneto, 94 cyls and super flows on the street, with stock cooling... with 28.24 miles to the gallon, couldn't have done it without help of a expert. 


Title: Re: ideas for my new engine
Post by: ESH on February 13, 2007, 13:47:07 pm
...some safety margins... 

When maintaining it be careful you don't lean on/over it if you have a metal fly or other metal objects in that region.
 :o


Title: Re: ideas for my new engine
Post by: Jon on February 13, 2007, 13:55:47 pm
If we are talking about IDAs the only thing you really can crew up is the low speed circuit, but if you know the trick of winding it in, and then back out until it "pops" in the exhaust, and give it 1 to 1,5 turn more out you will be fine.
You also need a good (retarded) ignition curve to prevent detonations when the loads get high.   


Title: Re: ideas for my new engine
Post by: Lee.C on February 14, 2007, 01:00:02 am
If you're looking to make 'very good' power then you'll want to eliminate any weak links and for my money that eliminates the use of a Berg (type1) 5 speed. It is inherently weaker than the 4 speed options out there. There are people out there that have had them live but I recently had to make up my mind on this one and decided against it and that's with a 'conservative' set up power wise. The way around it is either a 'built' box with GT ratios (or higher) or just go margianally shorter than the GT. On the 1/4 a GT doesn't really work that well and you'll never run the potential of your motor also if you do go long ratio you'll want torque so work that in to your engine combo. As for the Magneto, it can definitely be used on the street and would be fine for a once a week 'Saturday Night Special' type set up but probably not so good for a car used more frequently, again I thought about it but in the end decided on a different route though there are a few guys out there that have run them with drivers. I get the impression that you wouldn't mind greater authenticity at the expense of a few more hassles though. :)

A few people have said this now about the 5 speed and seeing as its such a BIG outlay maybe a PROPERLY BUILT 4 speed might be the way to go, Also why do you think that magneto's might not be best for street use- what are the disadvantages ???

And Thankyou Keith for corfirming what I already thought  :) 92's have been around for years and from what you say an 1835 is a pretty dam reliable lump :) So do you think a 2180cc lump is a good decission  ??? and do you think the heads I have will be good enough for this combo ???

As for the whole IDA thing I would never dream of trying to tune it myself not yet anyway - After building it I was planning on taking it to a good dyno - anyone know of a GOOD one and some one to tune it of course ???
I have also heard about "drilling a 3rd progression hole" ??? so whats this all about ???

Oh yeah your right Mat authenticity is what its all about :)


Title: Re: ideas for my new engine
Post by: Martin Greaves on February 14, 2007, 01:06:15 am
How about getting a Turbo or NOS for it then you can see how fast your monster tach and shift light works. ;D


Title: Re: ideas for my new engine
Post by: Lee.C on February 14, 2007, 01:22:13 am
How about getting a Turbo or NOS for it then you can see how fast your monster tach and shift light works. ;D

I was waiting for that  ;D my manifolds are already drilled for NOS  ;)


Title: Re: ideas for my new engine
Post by: Shubee2 (DSK) on February 14, 2007, 03:56:34 am
If it were Me I would Bulid an 82x90.5 Motor (2110 cc) I dont have anything againt 92's but I do like the Thick wall 90.5's they have more of a sealing surface from Barrel to Case (less leaks) it seems the Bigger the Bore the more Problems with Blow By Most of the fast cars these day are all going to the Clyde berg Breather boxes  the big motors seem to pump alot of oil up in to the breather box at high RPM In my old School 67 I Ran a 78x90.5 D Port Heads 10 to 1 compression engle 140 cam IDa's Bulit close ratio 4 Speed Trans this car ran 11:70's threw the muffers with slicks at OCIR I also ran a Magneto full time on the Street with no problems I had Joe Hunt Lock the advance out and set the timing at 28 Degree's  then bumped it up to 32' degree's at the track this is the car Motor is the one in the bottom picture


Title: Re: ideas for my new engine
Post by: Zach Gomulka on February 14, 2007, 04:16:04 am
If you want an old style engine combo, you have to use a displacement that was avaliable "back in the day". The only acceptable big bores would be 87, 88, 90, or 92, coupled with a 74, 78, or 82 stroke. There was a few more avaliable, but those are the popular ones. Since 87's are too small, 88's are rare as hens teeth, and 90's are no longer made, I would stick with 92's. I would build a 92x82 2180 using the new 92's with the thick cylinder walls (same O.D. as a 94) and a 1 pc crank with chevy journals and 5.325" rods for less case clearancing and a good rod ratio. Then you can have a little insurance if you accidentally run the motor a little hot, but you still retain that classic displacement figure. When you get the heads bored for the larger cylinders you could also install 42mm intakes, a touch more porting, and possibly open up the chambers a little ;) Or not, Im sure the heads would work fine in their current configuration, too. Or maybe a 92x78 2074cc with a welded VW crank and stock rods for a little less money. I reccommend a Engle 125 cam (with 1.25 rockers if you opt for the larger intake valves). 9-10:1 compression (you guys have good pump gas, right?!). 1 5/8" merge with dual QP's would be the only way to go :) The 3rd progression hole in IDAs helps the carbs transition from idle to main circut more smoothly. It wont help HP but it will help driveability, but the difference is more noticeable in stock stroke engines with less torque.

I wouldnt bother with the 5 speed. A 4.12 box with 3.78, 2.06, 1.32, .89 gears will get the job done for much less money. Use 3 gears in the quarter mile and you should still be well into the 13's on radials. And you can drive it home at a reasonable speed!

Good luck to you! What year body are you starting with??


Title: Re: ideas for my new engine
Post by: ESH on February 14, 2007, 20:15:26 pm
...also why do you think that magneto's might not be best for street use- what are the disadvantages?...

It is feasable but to my way of thinking it adds another layer of complexity over a 'standard' ignition system such as those offered by MSD, Mallory etc. I very almost went for a Magneto with my engine but on the advice of a couple of people decided not to.  I went with an 009 as an interim but have some Mallory bits (still) waiting to go in.  :)

What about a 010?  :o

Back to boxes, as Zach says it is possible to run 13's in three gears so a longer box would be fine though 'period' wise you could always go for a Porsche box, I think Dean Lowry went down that route pretty early on. :)


Title: Re: ideas for my new engine
Post by: Lee.C on February 14, 2007, 20:51:59 pm
Yeah you might be right Mat an 010 might be the way to go - Less complicated  :)

I had thought about a 356 box, but how do you fit them into a bug cos in a porsche they have a completly different craddle type mount  ??? And does anyone what the so called "airport" ratio's were  ???

Also thanks for the info Shubee and Zach - I think i am gonna go for the 2180  ;D as for the Valves I was already thinking about moving up to 42's and a bit more porting - does anyone what sort of costs this would involve ???

I already have the 1-5/8 header and I fully intend on using Dual quite packs - what else would I use  ;) :)

it also sounds like I won't need the 3rd progression holes - I don't mind it being a "bit of a bear" to drive  ;) :)

Oh yeah Zach I THINK I'm gonna start with a 67 - know of any good ones for sale out there in the States  ??? :)


Title: Re: ideas for my new engine
Post by: Rune on February 14, 2007, 23:31:46 pm
I like the 010 dissy with the old brown cap. Next to a magneto its the most old school choice. I run a 010 in my car. I put a pertronix in it an trigger it through a hidden MSD 6AL box. Works great.. Looks wise nothing comes even close to a magneto though  :)


Title: Re: ideas for my new engine
Post by: Jon on February 15, 2007, 00:09:24 am
The magneto is hassle free when its working, and the timing is set. But its one of the most reliable things out there, to my knowledge every propeller plane in the world has TWO installed. Why be mainstream?  ;)


Title: Re: ideas for my new engine
Post by: Lee.C on February 15, 2007, 00:24:54 am
I think you may have just made up my mind for me JHU  ;) :)


Title: Re: ideas for my new engine
Post by: Jon on February 15, 2007, 00:27:49 am
 ;) Keep an eye out for a freshly redone one on Samba, as a dud one can be costly to re-magnetize.


Title: Re: ideas for my new engine
Post by: Lee.C on February 15, 2007, 02:40:21 am
already looking dude 8)


Title: Re: ideas for my new engine
Post by: autobarnhauler on February 15, 2007, 18:40:38 pm
all cool stuff, and good advise, all i can say is "build the power in the engine, dont bolt it on"  :)


Title: Re: ideas for my new engine
Post by: Lee.C on February 15, 2007, 20:55:39 pm
all cool stuff, and good advise, all i can say is "build the power in the engine, dont bolt it on"  :)

A man after my own heart  ;) ie NO TURBO'S ;D ;)

whats your opinion on Magneto's on the street keith  ??? :)


Title: Re: ideas for my new engine
Post by: Martin Greaves on February 15, 2007, 22:19:14 pm
all cool stuff, and good advise, all i can say is "build the power in the engine, dont bolt it on"  :)

A man after my own heart  ;) ie NO TURBO'S ;D ;)

whats your opinion on Magneto's on the street keith  ??? :)

Dude we all know that all the fast street car have turbos. ;)


Title: Re: ideas for my new engine
Post by: Lee.C on February 16, 2007, 00:37:04 am
I thought you might drop your 2 cents in  ;) :) if you had your way we'd all be bolting hairdryers to our beloved flat 4's  ;) :)

You going to dubfreeze this weekend ???