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Figured I'd toss this in here since the build is nearing the end.
Back story:
My dad bought this 1977 Trans Am 400 4 speed car from a guy in Florida, 3 owner car, 88k original miles never opened the motor up or anything (allegedly). She was a light smoker (needs rings). Leaked every kind of fluid. We crated up the original motor and trans to keep with the car.
Goal:
500ish WHP with decent torque and drivability. Keep the factory shaker hood hooked to the intake and appear factoryish with working AC.
Build:
TSP 416 CI LS3 based motor with 11.3:1 compression
Stock LS3 heads (Thanks Rich2342) with .660 Cam Motion Springs
Texas Speed 229/244 .629"/615” 110 LSA, 107 ICL (Stage 2 LS3 cam from TSP but with the LSA moved over for the rumblies at stop lights).
Holley Single Plane carb style intake with Holley Terminator X (might change the intake around later if needed).
1 7/8 Speed Engineering headers
3" true dual Pypes exhuast
Tremec TKX 5 speed with the longest 5th gear they will sell.
Vintage Air
Little update on this. Car is running and driving, breaking in now.
Had some issues with non-authentic GM coils and Speed Engineering wires causing a break up. Is on a base tune as well made 508 RWHP on the dyno at 6000 where we cut the pull short due to some fueling problems that are now corrected. This was with 20 degrees of timing, and 12.0 AFR.
Going back post break in to get it the rest of the way tomorrow.
UMI 2406 mounts with Holley blackheart clamshells and poly 4th gen insides.
XFGM-10103M X-Factor trans cross member
Speed engineering 2nd gen 1 7/8th headers.
Very little adjusting was needed, it all slid right in. Fabbing the factory airbox/shaker now to fit, it actually is shockingly close just needs some adjusting.
She made a whopping 144 wheel horsepower prior on a different dyno. It was a tired 400 with 88k original miles, never opened up in desperate need of rings. It is now in desperate need of subframe connectors and poly body mounts, as when you lay into it, you can see the hood hit the fenders. Going to tackle that this weekend.
The dinky air filter also will probably go this weekend as well, was pulling 3 inHg of vacuum at WOT and taking the car out of the wide open timing table up top.
That is a really nice car and sounds like an excellent engine combo. How do you like the Holley Terminator EFI setup? Would you use it again or try something different?
I bet you will embarrass quite a few people thinking it’s a slow stock car, lol.
Isn't that the truth. Back in the day it might have kept up with most other cars with it's 7.6:1 CR ... and maybe 220 HP at the flywheel.
That really is the way to go. But I'm somewhat of a purist so I keep my built Pontiac 400 in my 2nd gen.
Car looks great ... and I'm sure runs great! That's a hefty cam ... but so doable with that manual trans.
Wish we would have done a port injection setup as the injectors in the TB dont really provide the atomization of fuel quite like a carb does. But it drives like a dream.
My dad was a bit Pontiac puristing this thing too but after he talked to butler and reviewed his options to make 500+ HP with AC this made the most sense. Hes talked about building this car since I was a little kid, nice to see it done.
I’m wanting to do the same thing ,I’ve been dying to get my old 78 trans am back,but I’m going to have to settle for another and drop a big stroker in the bay ,I was hoping to find a perfect roller lol..
Little update for winter. Got the scoop worked out. Had some issues with the Holley TBI, for some reason the IAC would always go to 0 and it would either surge or shut the car off. Turns out the secondary holes on the Holley 4 barrel throttle body were sticking slightly open after a wide open throttle event. Adjusted the spring and it drives great now. Also added an extension on the throttle cable assembly so it has more leverage on initial tip in.
We also got it out to the track and realized it's a 1 tire fire. Ran 12.3 at 122 with no posi traction. 12 bolt in the spring! We also had issues with the clutch at the track. Pedal would not wanna come back at the end. We had the reservoir mounted lower than the master and a slight leak. Mounted the reservoir behind the brake booster and bled it, feels great now after a beating.
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