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Hi you guys,

I am pretty new in the scene and just bought myself a wonderful 550Spyder replica about 1250lbs of weight. It has a 901 gearbox and a typeIV engine and I read so often that its "in the combo". Here are the data of the engine. I would be be very glad to hear some opinions about the combo and if it could be made it a little better or maybe even not.

Here you go:

2500 cc
103*75
103 race ring set
SCAT 5.5 Kcevy rods
22mm pins
75mm crank with chevy jour.
38mm exhaust valves
48mm inlet valves
Webcam 86a
Melling oilpump T-4
sep. oilcooler
lightened flywheel
ported heads and manifolds
MSD 6 ignition
Dual Weber 44IDF


Well, thats all I know about the engine so far, besides, that it has about 2000miles on it and all of the bearings etc. came new. I was thinking that a 48 weber might be a better choice but I am not sure. Also, what would you believe is the right ignition setting for this engine and how much hp should be developed at the flywheel when preciceley tuned? What do you think about this engine combo, does it make sence?

I would very much appreciate your thoughts on this combo keeping in mind, that it has a 901 5-speed and being used in a very light car.

Thanks very much,

Burg

I just forgot, it has the

single HD springs on the valves and
the hardened Webcam lifter

on it.

What would you think would be maximum rev?

Thanks again,

Burg

I don't have the knowledge to give much feedback on the combo...How is it to drive?

The exhaust header/muffler choice is very important. I hope you have more flow than shortened heater boxes.

Invest in some CHT guages and make sure your heads are not running too hot.

Ron

Hi Ron,

I can not tell you how it is driving it. Its not running yet, I still have to do some adjustments. Concerning the exhaust, it was especially fabricated for this setup and features ceramic coating. Does this help any further?

Thanks, Burg

Where are you located?

Who built the engine?

I'd run 45 Dells, but you can tune the 44s with jet and vent
changes also.

Did you buy PARTS or a car? Why isn't it running?

Oh yea, know where I can find a 56 C Speedster body?

Don

Hi Don,

I am located in Munich pretty close to the Wiesn;-) The car is running but >I could not test it yet. Its still sitting in the US. Hope it will get shipped this week. Its probably running a little rough and I am trying to mak it a good as it can get.

I think I saw a 356 speedster body for sale on ebay US lately. Not sure if its still there though.

Why do you think 45 carbs would be better?

Burg

Burg wrote:Hi Don,

I am located in Munich pretty close to the Wiesn;-) The car is running but >I could not test it yet. Its still sitting in the US. Hope it will get shipped this week. Its probably running a little rough and I am trying to mak it a good as it can get.

I think I saw a 356 speedster body for sale on ebay US lately. Not sure if its still there though.

Why do you think 45 carbs would be better?

Burg

Muchen, eh? I used to drive by there every other week, as I was going from Frankfurt to Hitler's Eagle's Nest, in Berchtesgaden.

I used to LOVE that WEISEN bier!

Anyway, I like Dells over Webers anyday, and 45s the best for a type 4.

Don

I'll hazard a guess that the single springs and those huge valves will limit your RPMs to ~6500 RPM at best, but it sounds like a reasonable combo, save for the head sealing issues, but those will come later.

Keep an ear out for the leaks, and get some nickies etc for later.

If it has the T4 2.0 rods (VERY likely with a 71 crank) you might really want to take a peek and make sure they have ARP bolts, have 12 pt nuts for a visual aide.

With those rods, ~6500 RPM is about it anyway. Same for the 86a IIRC, all done by then, so it works out.

In a 600 Kg car, it should... accellerate briskly;-) Might want to look for a taller final drive in the trans.

If you ever stop in Freising, and have a urge for good Chinese food, There is a place in the Isar hotel that is very good...
Have the Duck. It rocks.

Thanks PD,

will check out the ducks at Freising for sure;-) My engine has a 75 crank and SCAT 5.5 rods though. Does this make any difference?

Thanks again

Burg

IiiiiiEEEEE.... I must have mentally mixed up your specs with another motor.
(I plead late night posting)

It's still going to be more of a stump puller than a high rev demon.

If you had a different cam and valvetrain, 8K+ would be fine with those rods and a good balance job.. and aftermarket heads.

The cam is still going to make her fall off @~<6500...and the single springs will likely enforce it before that with the 48mm intakes, assuming iron lifters.

Has the motor run? No lifter problems? Make sure...

Yours might be a GREAT candidate for those killer T4 heads we saw on some thread the other day... The stock heads are going to be your rev limiter as well on a motor that big. (flow)

http://shoptalkforums.com/viewtopic.php ... 0&start=30

The T1 exhaust ones... Not the OHC ones (yet)

Having said all that, I point out that your motor should put out ~>160-180HP, and in a 600Kg car... That should be brutal, like riding a top end sport bike, but with more comfortable seats.

A 1600DP feels fast in a buggy about the same weight as you speedster...

Thanks you guys for all the informations. 160-180hp at the flywheel? Hm, I am looking for 200 at the wheels! What would be your suggestions to get there?

Thanks

Burg

50 shot of nitrous...

You are going to have MAJOR issues getting what you HAVE to the ground in that light of a car.

I would suggest driving it first--- You may find that what you have is scary fast already.

If you have the big bucks, those heads above and a set of 102 nickies, different cam, should put you in the ~250HP range.

BTW, did you go swing axle or IRS?

Hope you have a large budget....... It can be done, I did it with a 2739 @10:1. The owner frequents this forum..

Its IRS. Here is a picture of it in its present state:


http://123homepage.hometown.aol.de/_cqr ... html?cc=de

What do you think?

Burg

ups, link does not seem to work. Try this one:

http://hometown.aol.de/oskarbalu/homepa ... marke.html

Thanks,
Burg