Optimum Type 4 for road racing Options

[Charles Freeborn]

Title says it - taking opinions on a competitive T4 used for vintage group road racing. Primary tracks will be PIR (Portland), The Ridge and ORP. PIR is a relatively flat high speed 12 turn track. The other 2 are much more technical - slower, more turns, shorter straights.
Cases need to be EA or EB to qualify for the run group I'm shooting for (F). Currently have a 94/71 with big valve heads, 9.5:1, IDF 44's Webcam 86B. It's sound, but getting tired - showing some cracking in the heads, so if I get another season from it I'll be happy. Prefer to keep CR in the range that can run on pump gas - also durability is a factor.
Some thoughts/questions:
Shorter stroke / bigger bore for better top end? - with current gearing I'm running out of redline on longer straights.
Billet crank from SCAT?
Split Port heads from SCAT?
Mahle Euro pistons or CP or JE.
Nickasil cylinders worth the expense?

Very interested in hearing the specs on any of your builds - how they behaved and how long-lived they were.

Gearbox is a separate issue- will get to that when I've got the engine specs sorted.

Many thanks.

[GregAmy]

What are the regs? I find it interesting that you have to run a specific case ID, yet the really important regs seem to be Way Wide Open.

And of course...what's your budget?

I run mine in historics, where regs don't exist* and declared displacement is solely by the honor system (among thieves). So power is ultimately limited exclusively by the wallet.

GA

*Regs that are unenforced or unenforceable are not regs.

[Charles Freeborn]

What are the regs? I find it interesting that you have to run a specific case ID, yet the really important regs seem to be Way Wide Open.

And of course...what's your budget?

I run mine in historics, where regs don't exist* and declared displacement is solely by the honor system (among thieves). So power is ultimately limited exclusively by the wallet.

GA

*Regs that are unenforced or unenforceable are not regs.

I want it to have the appearance of a 1.7 and keep it at 2.0L +-.
Less than $10k

Sanctioning bodies are ICSCC (FIP class), SOVREN (small bore group) and to a lesser degree SVRA (maybe 1 event per year).

[GregAmy]

I want it to have the appearance of a 1.7 and keep it at 2.0L +-.

See? (IMG:style_emoticons/default/happy11.gif)

Sounds like you need to rebuild what you have. And send us a photo of the car so we can protest you. (IMG:style_emoticons/default/av-943.gif)

[Charles Freeborn]

I want it to have the appearance of a 1.7 and keep it at 2.0L +-.

See? (IMG:style_emoticons/default/happy11.gif)

Sounds like you need to rebuild what you have. And send us a photo of the car so we can protest you. (IMG:style_emoticons/default/av-943.gif)

Pretty commonplace 'round here... I'll post a pic of your car just to keep the whiners off the scent.. (IMG:style_emoticons/default/smilie_pokal.gif)

[GregAmy]

Pretty commonplace 'round here... I'll post a pic of your car just to keep the whiners off the scent.. (IMG:style_emoticons/default/smilie_pokal.gif)

(IMG:style_emoticons/default/beerchug.gif) ..."if everybody's doing it" then why have rules at all? Anyway...

You're already running an oversize 2L engine with oversize valves and oversize carb chokes in a 1.7L, stock valve size, 38mm choke class...I mean, man, how much more do you need to win? I'd say rebuild whatcha got and spend the rest on more track time (that's why we do this, right?) Raby can probably set you up with a good strong build.

[Charles Freeborn]

Pretty commonplace 'round here... I'll post a pic of your car just to keep the whiners off the scent.. (IMG:style_emoticons/default/smilie_pokal.gif)

(IMG:style_emoticons/default/beerchug.gif) ..."if everybody's doing it" then why have rules at all? Anyway...

You're already running an oversize 2L engine with oversize valves and oversize carb chokes in a 1.7L, stock valve size, 38mm choke class...I mean, man, how much more do you need to win? I'd say rebuild whatcha got and spend the rest on more track time (that's why we do this, right?) Raby can probably set you up with a good strong build.

Current engine is as fresh as possible, but was built nearly 20 years ago. Heads are showing signs of cracking. If it takes a poop mid season I'm out. Idea was simply to build a spare that eventually would become primary.

I'll run it in a variety of classes and sanctioning bodies - all with different regs. Some are below 2.5L where I'll be back of pack at best - others are the "small bore" vintage groups that have literal millionaires with complete race teams. In vintage, in these parts, If someone is kicking ass or obviously sandbagging they move them up a group (or 2). That is how the regs are "enforced".

[GregAmy]

Sounds like nobody really gives a crap (or is even checking stuff), so I'd not worry about the need to "appear" to be 1.7 and just go find a good 2L build candidate...and go to town on it.

Grind off the engine code and claim it's a new case, who's gonna know the difference?