I am collecting ideas and planning a 350 based small block tpi motor. 350 based meaning that anythinhg built off of a 350 block including strokers. I am looking at naturally aspirated as well as supercharged, no nitrous. Please post your motor build along with gas mileage, tranny, and gearing ratio. I am interested in seeing who gets the most horses and quickest 1/4 miles with the best gas mileage. So far Mike of the 383 TPI post looks to have the best at @12.5 seconds and 21 mpg highway, 16 city.
Can you beat that?

Thanks for the info,
Mike3

 

I'm guessing my dad didn't beat mike, but he has a 90 Formula with a TPI ZZ4. SLP runners, hooker super comp system, lingenfelter intake, not sure what injectors, custom chip, 2:73 rear, stock 700R4 with a B&M flexplate. It gets around 20 some mpg, and I would guess low 13's.

 

I am running AFR 195s, Holley Stealth Ram, Supercomps, 355, roller cam with small duration and high lift, 700r4 with 3000 lockup, 3.73s. I get about 13mpg in town (probably because of the huge stall) and about 18 on the highway. I dont think I can win this little contest. She drinks 93 octane though!

Edit.. Since I just finished it in November, I havent yet been able to get to the track. I think it will run low 12s maybe high 11s on the motor.

 

I can't really give you any numbers but if you want high horses and good gas mileage then de stroke the motor. It will kill your torque but a 302 (4.00in bore x 3.00 in stroke) can buzz out to 8,500rmps.

 

If you want "buzzing" get an import, if you want real men's power don't de-stroke anything...

 

True that but he did say gas mileage.

 

Destroking will not improve your HP/gas mileage ratio.

Nitrous is the only real way to have a track screamer and good economy in the same package.

 

There is a guy on here that is making 500hp and getting 21 MPG its a 355 engine with a supercharger and its TBI as well, its Kingtal0n's car the engine build up was 13,000 total. Here is the thread that tells all about it
https://www.thirdgen.org/techbb2/sho...readid=144692. And this site has some pics of the engine. http://geocities.com/kingtaling/ If he had a T56 he might be able to get 25 MPG.

 

Sorry, but destroking also does nothing for RPMs. You can make a 383 "buzz out" at 8500 rpm's if you build it right. The reasons 302's had such high powerbands is the top end. They had a huge mechanical cam, carb, intake, and heads that were made to make power on the top end. If you build and balance a 383 with a good forged bottom end and had a similar top end, you would make more torque, and still "buzz out" at 8500 rpms. Destroking is something to do when you have to meet specs for a certain racing class. Not to improve gas mileage. Just my 2c.
Matt

 

Why do motor cycles have such high revs? large bore small stroke.
A 302 will rev higher that a 383 if they are built to exact specifications. why? it has less recroprocating (no i can't spell)mass and the pistons move less per stroke therefore it will be able to spin faster.

 

I agree to an extent. Motorcycles make power at well over 8500 rpm. They have such small displacement and small internals that such high rpms are feasable. However, spending money to destroke an engine for gas mileage is a waste of good money. It is probable that destroking the engine would require a specialized rotating assembly, probably forged. A stroked 383 with a solid and balanced forged bottom end will rev to a nice high rpm too. You simply need the top end to make power at such high rpms. For all intents and purposes, you might as well use the cubes. Destroking will not help gas mileage enough.

 

i get about 17-20 mpg city and about 22-25 highway with my combo.. and thats runing rich now.