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Large bore


Bandit
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7 hours ago, Bandit said:

Just curious.. since i can't have a 5.3, can I do a 7.4? 

 

The car is 4200 starting point... And the 7.4 was stock three years. 

Was the 7.4 offered in one of the cars on the VPI list (not including high performance /special edition models)

https://www.chumpcar.com/downloads/VPI_Table_Dec2016.pdf

if it is in a car on the list, you are allowed to run it. 

Edited by enginerd
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7 hours ago, Bandit said:

Just curious.. since i can't have a 5.3, can I do a 7.4? 

 

The car is 4200 starting point... And the 7.4 was stock three years. 

 

I am trying to understand your question. 

 

Are you saying:

A Chevrolet 3rd generation small block Vortec 5300, or LM7/L59/LM4 does not come in any car on the VPI table. Does anyone know if I can run any big block Chevrolet engine with 7.4L of displacement?
_____________________________________________________________________________________________________

 

If the above is what you  are saying, then I see many 1970-1975 Chevrolet vehicles on the list you could use for the basis of an engine swap. 

If you are asking about the Vortec 7400 ( L29/L21), no vehicle on the list has the engine from the factory.....as far as I know. 

 

 

 

Is this what you were asking? Did I answer your question?

 

What is a 4200?

 

I am lost........................

 

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I think he's saying that with a 5.3 swap, the car that he's thinking about swapping is 4200 pts and with a '70s 454 (Caprice, Impala, truck) is (as a guess) 243 pts.

 

I think the best way to make sure is to email Mike or Phil and get preapproval of the swap.

 

On the same topic: the swap rule states that the highest VPi version of the car is to be used for the base VPi before the power to weight is accounted for. In the case of a high performance or special edition car that was offered from the factory but isn't called out on the VPi list, is it the highest VPi on the list and any "adjustment" points for power to weight? No 50 pt swap penalty since the car isn't actually getting a swap but the same PWR penalty points?

 

Seems to me that would be fair and should keep the intent of the PWR adjustment/ceiling without adding a swap penalty to a non-swapped car.

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7 minutes ago, mender said:

I think he's saying that with a 5.3 swap, the car that he's thinking about swapping is 4200 pts and with a '70s 454 (Caprice, Impala, truck) is (as a guess) 243 pts.

 

I think the best way to make sure is to email Mike or Phil and get preapproval of the swap.

 

On the same topic: the swap rule states that the highest VPi version of the car is to be used for the base VPi before the power to weight is accounted for. In the case of a high performance or special edition car that was offered from the factory but isn't called out on the VPi list, is it the highest VPi on the list and any "adjustment" points for power to weight? No 50 pt swap penalty since the car isn't actually getting a swap but the same PWR penalty points?

 

Seems to me that would be fair and should keep the intent of the PWR adjustment/ceiling without adding a swap penalty to a non-swapped car.

What  make, model or year car are we even talking about?

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The VPI Table includes Chevy K/C series Truck up to 1999

 

7.4L 

1988–1995 230 hp (170 kW) @ 3600 RPM 385 lb·ft (522 N·m) @ 1600 RPM
1996–2000 290 hp (220 kW) @ 4000 RPM 410 lb·ft (560 N·m) @ 3200 RPM

 

Edited by thomasp
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On 3/24/2017 at 2:20 PM, mender said:

Don't forget to claim the head swap. :)

Yeah, more than just compression is different there. Had a 70 Deville ragtop with the 375hp 472. At 5000 pounds it still smoked a few supposed musclecars. With 2.93's.  525 torque helped. Lighter motor than the Chevy BB btw....

Edited by Bandit
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On 3/24/2017 at 10:15 AM, JDChristianson said:

Well at least with a 454 the car won't be heavy in the front.   And should get fantastic fuel Milage. ?

Correct. However it also has a big gas tank.  Unleaded at 2.25 a gallon is the least of my worries after entrance fees, driving suits, cage, fuel cell, helmets, etc. 

Edited by Bandit
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I just like the fact no one has said it's  not legal. Picking the starting point up tomorrow.   22 gallons stock sounds great, but it will still be a struggle to make 1:50 or so. Miss the 7 hours races at RA already. Helped fuel hogs...Probably why they got rid of them. Poor choice in my eyes. Fans like to see the fastest car win.

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Btw Anyone here on the forum know anything about the old ass 72 or so Grand Prix that ran at RoadAmerica a year or two ago? From vids it looked damn impressive for something that rivals a Tiger tank for weight.

 

Seems I saw something about some GM engineers on that team but may be mistaken. Curious about drivetrain as it looked competetive cornering.

Edited by Bandit
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