Factory Appearing (F.A.S.T) Restomod Questions

[TorRed]

Hi All,

I'm strongly considering a 'mostly' stock appearing rebuild of my 1970 Roadrunner (383, 727 Auto, 8.75 Rear) and have some questions for any of you that have taken that path. I already have a G/V overdrive. tight FTI 3000 stall converter for the trans and 4.10 gears for the rear. Not sure about the converter but pretty sure I'll go to a higher gear like 3.91, 3.73 or even 3.55 depending on where the engine's rpm range ends up. As for the motor I'm looking at either the 432 or 489 stroker kits from 440Source but not sure the larger kit will work with stock intake and exhaust? I'll go with either the TTI 2.5" or 3.0" manifold back H pipe exhaust but want to swap the Turbo mufflers for Dynomax UltraFlows. I have the original intake but have a larger 70/71 440 AVS 750cfm carb I'd like to use but again don't know if that's enough carb for the 489 c.i. stroker? I also have a Lunati hydraulic roller I'd like to use but once again it was bought for a higher HP build so don't know if I'm going to have to go milder? I know the 489 will tame it to a large degree so that has me leaning to the 489 for that and for the extra HP it would bring. I would greatly appreciate any and all opinions but especially those who've gone down this path before and have advice on pitfalls, what worked, etc. I've read some really good articles about these types of builds but would really value the opinions / experience of the forum.

Thanks in advance,
Jim

 

[R413]

When cruising down the freeway the engine RPM needs to be higher than the stall speed of the converter. Or you will be slipping and building heat and have no fuel mileage. So plan your gear ratio around this.

 

[TorRed]

When cruising down the freeway the engine RPM needs to be higher than the stall speed of the converter. Or you will be slipping and building heat and have no fuel mileage. So plan your gear ratio around this.

Generally, I agree. However, I have read that at highway speeds with an overdrive it takes much less HP to stay at a given speed that effectively the 'stall' of the converter especially a tight one will drop and not slip at lower rpms. How much it drops is hard to say but somewhere I read 500 rpm is not unusual. Again, would love to get folks actual experiences with this.

Thanks,
Jim

 

[PRHeads]

The stock intake is a huge impediment for making real power……..especially when coupled with exhaust manifolds.

A pump gas, truly street friendly HR cammed combo will be very lucky to get close to 500hp.
Especially if it’s cammed properly for the low cruise rpm that would accompany tallish gears and an OD unit.
Probably end up closer to 450hp.

To put it in perspective……
Low deck 511, ported 906’s(280cfm), 12:1cr, .630 lift solid roller, reworked 301 manifold, Ede 800AVS, HP ex manifolds…….525hp on the dyno.
11.58@117 @3670lbs in a 69 Bee on bias plies.

 

[TorRed]

The stock intake is a huge impediment for making real power……..especially when coupled with exhaust manifolds.

A pump gas, truly street friendly HR cammed combo will be very lucky to get close to 500hp.
Especially if it’s cammed properly for the low cruise rpm that would accompany tallish gears and an OD unit.
Probably end up closer to 450hp.

To put it in perspective……
Low deck 511, ported 906’s(280cfm), 12:1cr, .630 lift solid roller, reworked 301 manifold, Ede 800AVS, HP ex manifolds…….525hp on the dyno.
11.58@117 @3670lbs in a 69 Bee on bias plies.

That's great info, thanks!