Build help 4.3 or 4.5 stroke street/strip build

Trying to decide on which stroke to go with. I've searched the topic and a few have said the 4.5 stroke increases wear and it's not worth doing for longevity. This will be going into a 4000lbs 79 F100 that will see a lot of street use as well as the track. Pump gas is a must.

Here is what I have for this build:
Stock D1 block converted to 4 bolt mains currently assembled
Stock crank offset ground 4.14
Eagle H beams 6.8
JE flat tops (3 are melted from previous owner, bad nos tune up)
Motorsport A460 heads 2.3 valves fresh and mild porting by a local shop (410cfm)
Motorsport A460 intake
Pro systems 1090 dominator
2 1/8 - 4" headers

I'm hoping to make a lot more then my current TFS street motor. And it sounds silly but I planned on going with a solid flat tappet as I've had issues with rollers in the past.

tfsbbf466 wrote:Trying to decide on which stroke to go with. I've searched the topic and a few have said the 4.5 stroke increases wear and it's not worth doing for longevity. This will be going into a 4000lbs 79 F100 that will see a lot of street use as well as the track. Pump gas is a must.


I'm hoping to make a lot more then my current TFS street motor. And it sounds silly but I planned on going with a solid flat tappet as I've had issues with rollers in the past.

Personally, I think this is way to much head for a regularly driven 4,000 pound street truck but, maybe OK for cruise nights, Sundays and Holidays.

With a D1 block, I would use a 4.300" stroke crankshaft.

Everyone's idea of street use is slightly different. People around here call their cars "street cars" and I never see them not on a trailer. My truck isn't a daily driver. But I drive it to the track and on nice days. It's main objective is too be fast but reliable enough to drive on the street without causing too much harm.

Would you recommend the 4.5 crank if I had stepped up to a good block?

Also forgot to mention the truck has a decent built c6 with some rollerized parts, a Broader trans brake vb, and a PTC nitrous converter. The truck will see moderate nitrous use. It has been bottom 10s as is on spray with a best of 9.98 130. I'm hoping to be consistently in the high to mid 9s on pump gas.

4000+ lbs??......4.5 stroke!!

Given the cylinder head and the wt. of the vehicle more displacement would be very productive.

I'd agree with Lem bigger is better

So you guys don't see any negative effects of the larger stroke? I would rather have the 25 extra cubes but wanted to make sure it was worth it. I'm hoping to make good power with this motor then spray a nice amount on top.

4.300" with a 6.800" rods is an easy deal.

Lem,
With a 4.5 stroke, wouldn't he be better sourcing out a later D9 block?

How much of REAL issue is the difference in cylinder length?
Thanks,
Drew

A D9 block would be .200"+ on the ones I measured.

Same question, but for a 3000lb car for Drag Week (so "lots" of street miles)? I'm mostly set on 4.5 but question whether 4.3 would be a better choice, especially since it's a small tire car. (4.65" bore)

The rest of the engine will be built for the test , A96 block, large diameter lifters, steel shaft rockers, etc.

I have a customer that runs the 'power tour' deal every year. P51, A96 and 4.500" stroke.....no issues.

Thanks, Lem. I have Oliver 6.8 rods....those work just as well on a 4.5" ?

Is a 7" inch rod and custom piston out of the question??

BBFTorino wrote:Is a 7" inch rod and custom piston out of the question??

If you don't want any dish and are satisfied with a 1.060" compression distance piston, then it would work.

windsor wrote:Thanks, Lem.  I have Oliver 6.8 rods....those work just as well on a 4.5"  ?

Sure.