Phreakish
Well-Known Member
Soon after buying my dart I found the 318 was trash. I figured "why pay almost the same for a replacement when for a little more I could have a stroker?" and so I bought a (no longer available) blueprint 408 shortblock. Which, by the way, was an awesome purchase.
I kept the LAX 1.92 heads that were already on the 318 (also already had headers and 3:91 gears). The problem with the stroker is that even with a ~240 @.050 cam (~.510 lift) all the fun is over at 5800 rpm. I run a 4spd, and so I get about 2300 rpm of 'fun' before having to shift. I doubt a much bigger cam will help a whole lot (and I'm already spring-limited as the heads are cut for 1.250 OD springs). It sucks, it's boring! It's like driving a truck! It's too tame and lacks all of the screaming revs that should be associated with a muscle car.
I don't race, it's a cruiser and loud toy that pisses off neighbors and yet it lacks the fun-factor that the 318 had (because it wound-up to 7200 all day, even though it was not very quick). I want to hang onto a gear for more than the 2-3 seconds it takes to get to the next shift. Instead I wind up rowing through the gears or just skipping 2nd altogether. It pulls like a train but drops back to 2300 after each shift and I seriously wish it would climb higher in the revs before falling off a log. It'll run all the way to 7k, but there's notably less pull as I go beyond 5600, and after 6 it's like beating a rented mule. Don't get me wrong, it's quick and it pulls and is exactly what I *thought* I wanted. But when it comes to a 'fun' car, it's not as fun when it's practical. A fun car should be a little closer to the ragged edge than most seem to shoot for, I think. Even if it only makes 400 horse, it's a lot more 'fun' when to rip right up through the revs. Trailer-towing rpms just aren't exciting, even if it DOES make 550+ ft-lbs..
If I had to do it again, I wouldn't opt for a stroker shortblock unless I had MUCH better flowing heads to match and I'd go with the max lift I could and wouldn't be afraid of duration in the ~250 range @.050 either. I'd also opt for 10.5 or 11:1 since it's easier to lose compression than gain it and most calculators are generous anyway... Even with my '62' cc heads and the KB356 pistons BP uses, the compression comes out around 9.8 with .039 gaskets. If I build one myself, I'll use KB107's (even with the 60cc TF heads).
As it sits now, my finger is hovering over the button to order some TF heads because by the time I get my LAX heads worked over, it would probably be a wash as far as cost goes (and take less time and comes with a warranty) and with a stroker there's no such thing as too much head. Unless it's for a truck.. With how fast the piston comes off TDC I just can't see any justification for low-flowing heads. That slowness off TDS also means the exhaust has a harder time pulling in the intake charge especially with a closed-chamber head, and so the head has to play catch-up as soon as that piston heads back down. I have no practical experience with it, but the physics definitely make sense to me and it seems to trend well with most racers using strokers too. Almost makes you wish for a stroker piston with a lot higher pin location... but that's a different topic.
I kept the LAX 1.92 heads that were already on the 318 (also already had headers and 3:91 gears). The problem with the stroker is that even with a ~240 @.050 cam (~.510 lift) all the fun is over at 5800 rpm. I run a 4spd, and so I get about 2300 rpm of 'fun' before having to shift. I doubt a much bigger cam will help a whole lot (and I'm already spring-limited as the heads are cut for 1.250 OD springs). It sucks, it's boring! It's like driving a truck! It's too tame and lacks all of the screaming revs that should be associated with a muscle car.
I don't race, it's a cruiser and loud toy that pisses off neighbors and yet it lacks the fun-factor that the 318 had (because it wound-up to 7200 all day, even though it was not very quick). I want to hang onto a gear for more than the 2-3 seconds it takes to get to the next shift. Instead I wind up rowing through the gears or just skipping 2nd altogether. It pulls like a train but drops back to 2300 after each shift and I seriously wish it would climb higher in the revs before falling off a log. It'll run all the way to 7k, but there's notably less pull as I go beyond 5600, and after 6 it's like beating a rented mule. Don't get me wrong, it's quick and it pulls and is exactly what I *thought* I wanted. But when it comes to a 'fun' car, it's not as fun when it's practical. A fun car should be a little closer to the ragged edge than most seem to shoot for, I think. Even if it only makes 400 horse, it's a lot more 'fun' when to rip right up through the revs. Trailer-towing rpms just aren't exciting, even if it DOES make 550+ ft-lbs..
If I had to do it again, I wouldn't opt for a stroker shortblock unless I had MUCH better flowing heads to match and I'd go with the max lift I could and wouldn't be afraid of duration in the ~250 range @.050 either. I'd also opt for 10.5 or 11:1 since it's easier to lose compression than gain it and most calculators are generous anyway... Even with my '62' cc heads and the KB356 pistons BP uses, the compression comes out around 9.8 with .039 gaskets. If I build one myself, I'll use KB107's (even with the 60cc TF heads).
As it sits now, my finger is hovering over the button to order some TF heads because by the time I get my LAX heads worked over, it would probably be a wash as far as cost goes (and take less time and comes with a warranty) and with a stroker there's no such thing as too much head. Unless it's for a truck.. With how fast the piston comes off TDC I just can't see any justification for low-flowing heads. That slowness off TDS also means the exhaust has a harder time pulling in the intake charge especially with a closed-chamber head, and so the head has to play catch-up as soon as that piston heads back down. I have no practical experience with it, but the physics definitely make sense to me and it seems to trend well with most racers using strokers too. Almost makes you wish for a stroker piston with a lot higher pin location... but that's a different topic.
