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383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Tech / General EngineIs your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
...I'm back to work on this thing. Credit card has been paid off!
I'm working on the final install now. Intake has been bolted down and engine was transferred to a rolling cradle that will be modified to hold a radiator and battery so I can run and tune it before I spend time putting it in the IROC.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Originally Posted by UltRoadWarrior9
...I'm back to work on this thing. Credit card has been paid off!
I'm working on the final install now. Intake has been bolted down and engine was transferred to a rolling cradle that will be modified to hold a radiator and battery so I can run and tune it before I spend time putting it in the IROC.
Looks shockingly similar to what will soon be pushing my Express van around.
I am working on a nicely built 383.
Right at 11:1 compression
Summit Racing 0.030" over 880 Vortec block
Eagle 1-piece rear main lightweight crank,
6" H-beam brushed rods with floating pins
Weisco forged flat tops with 2 deep valve reliefs
File fit rings 0.018 top and 0.016 2nd
SFI 8" Fluidampner milled for the 24x reluctor
GMPP Single roller timing chain
Fully balanced
Coated rod and main bearings
Lloyd Elliot Ported Assault Racing 205cc heads
2.02/1.60 valves and dual springs
7/16 screw-in studs and adjustable guide plates
Heads milled 0.020" for flatness
210cc ports 64cc deshrouded/polished chambers
Flow 274/190 @ .500 and 291/193 @ .600
4.030" x 0.38" MLS cometic head gaskets
Comp Cam 215/224 @ .050, 110 LSA, 106 ICL
0.578" intake and exhaust lift
1.7 Scorpion 7/16" non self aligning rockers
Short poly locks for added clearance
Rhodes variable roller lifters
Hardened 0.080" wall Comp Magnum pushrods
Aluminum centerbolt short valve covers
Stock steel ones won't clear the rockers
Slightly modified a/c compressor bracket
L31s a/c bracket will not clear LH valve cover.
Mercruiser dual plane MPFI intake port matched
Buick 3.8 SC injectors @ 58 psi for 42 lb/hr
102mm to carb elbow and matching 102mm TB
4" custom air intake
LS3 cartridge style MAF
Stock LS Van air cleaner with a K&N filter
Doug Thorley Tri-Y headers
Factory dual 3" exhaust piping
Thunderbolt 3" spun metallic core cats
Dual 3" in and 4" single out muffler
EFI connection 24x reluctor
Holley aluminum timing cover
Aluminum L31 distributor for cam sync
LS Truck D585 coils
1 meg 2005 LQ4 Van PCM (Blue/Green connector)
Flex fuel enabled with the Ethanol sensor installed
5qt truck pan
Windage tray, crank scraper and oil pump baffle
High pressure big block oil pump
March 3 piece 25% underdrive pulleys
Flowkooler Vortec truck water pump
GM 19.5" 11 blade fan on a standard clutch
34" wide 454/8.1 van radiator with oil cooler
170°F thermostat
With any luck it will be in the 500 hp and 500 tq range on pump gas and 550 hp and 550 tq on E85 and be done making its power under 6,000 rpm.
With the Rhodes lifters I know it will sound like a solid roller cam but I want a very stock sounding smooth idle.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
I've made a change in the choice of pushrods. Instead of the Manley .080" thick 3/8"wide 7.100" length pushrods which do have the slightest interference issues with the AFR210's. I've gotten in some .120" thick 5/16" 7.100" Manley pushrods.
Also, got in some bolts to finalize the intake mounting on the 4 center bolts. The one's I used were fine for mounting to the heads, but too long on the center bolts. ARP 3/8-16 1" under head length solved that problem so they wouldn't hit the pushrods. I chose 12 point ARP bolts for almost everything, except the header bolts for the OBX Racer SS 1 3/4" longtube headers. For those I chose 6 point in order to get a grip with an open end wrench since they're so close to the tubes.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Originally Posted by Fast355
Mercruiser dual plane MPFI intake port matched
With any luck it will be in the 500 hp and 500 tq range on pump gas and 550 hp and 550 tq on E85 and be done making its power under 6,000 rpm.
With the Rhodes lifters I know it will sound like a solid roller cam but I want a very stock sounding smooth idle.
Interesting as I've been considering a dual plane to MPI EFI conversion for my LT1. The more I read of a dry flow dual plane EFI the more sense it makes for a street motor. Didn't know Mercruiser had been using this for decades.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Originally Posted by cardo0
Interesting as I've been considering a dual plane to MPI EFI conversion for my LT1. The more I read of a dry flow dual plane EFI the more sense it makes for a street motor. Didn't know Mercruiser had been using this for decades.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Been fitting a starter to the 880 block. Finally went with a new REMY manufactured starter made for a 1996 LT1 Corvette. It's a nice looking unit and hardly has any clearance issues. There's is only 1 tight spot that I'll have too worry about. You can read about that HERE. It'll probably involve a little grinding on the starter and dimpling of the header.
Now the problem I have is the flexplate I got with the Scat forged bottom end kit, 2 years ago, is a 14" 153 tooth and obviously won't work. Looking for a good 153 tooth 12.75" diameter SFI rated flexplate. Will order it next week....
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
With this starter I've had to dimple the #6 cylinder tube. I'd like clearance of 1/4" to 3/8" in order to fit a heat shield in between the header and starter.
I made some custom pieces to do a smooth dimple instead of just hammering. Measured these header tubes @ 2"OD. Holy crap I thought they were 1 3/4"...
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Originally Posted by UltRoadWarrior9
With this starter I've had to dimple the #6 cylinder tube. I'd like clearance of 1/4" to 3/8" in order to fit a heat shield in between the header and starter.
I made some custom pieces to do a smooth dimple instead of just hammering. Measured these header tubes @ 2"OD. Holy crap I thought they were 1 3/4"...
That is about where 14 gauge 1-7/8" tubing would fall.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Ordering a 12.75" Scat flexplate meant for 'rear' external balance. When I bought the forged balanced bottom end 2yrs ago, I didn't spec which flexplate I needed and was sent a 14" version, which doesn't mate properly to the starter/header combo I've chosen.
Last edited by UltRoadWarrior9; Aug 1, 2019 at 06:43 PM.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Progress report:
Today I got in the 153-tooth, 12.75" Scat flexplate and mounted it. A few days ago I shaved off some metal from the 96 Vette starter so it mounts flush to the 880 block. Also mounted both headers with the copper gaskets. Today I also switched out the 3.8"wide .080" sidewall 7.1" long Manley pushrods to the 5/16" wide .120" sidewall 7.1" long Manley pushrods. I also got the oil dipstick situated.
Re: 383 Build. 500HP goal. Can I retain the TPI Intake?
Originally Posted by UltRoadWarrior9
I'm near Wake Forest...
Are you still in WF? I'm just down the road. I built a real similar combo for my iroc last year, 383, 11:1, afr 195's, xfi292, miniram, efi connection 24x. It's been reliable, driveability with a 6 speed has been great and it sounds and runs amazing.
Re: 383 Build. 500HP goal. Can I retain the TPI Intake?
Originally Posted by GTA matt
Are you still in WF? I'm just down the road. I built a real similar combo for my iroc last year, 383, 11:1, afr 195's, xfi292, miniram, efi connection 24x. It's been reliable, driveability with a 6 speed has been great and it sounds and runs amazing.
Sweet! Yes, Im closer to Bunn, I'll bet you're 10 minutes away! Gotta check out your setup man! I'll PM you after work tonight.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
PM sent.... Liking what I see on efi connection site. thx for posting. Considering all options for ignition, but I'll probably stick with GM 7730 ECU and Moates programmer to start this thing.... Still, alot to consider and don't want to waste money. Gotta think long term here, which I why it's been saved for last. Still doing research.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Today, I adjusted the lash on the T&D 1.6 rockers. The CompCams short travel lifters spec'd a 1/4turn. After I was done, there's no interference between the 5/16" pushrods and AFR 210 heads like there was with the 3/8" pushrods, still very tight clearance. Looks close to .030"...
I decided to go cheap for the ignition system and go with GM HEI only in order to get this thing started quicker.
Just ordered a 7730 ECM (EBL P4 FLASH) from DynamicEFI, a 1992 Z28 HEI distributor from Rockauto and 8.5mm MSD superconductor wires and loom kit from Summitracing.
I'll need to focus on finishing the engine running stand next. I had to cut sections out to make room for the flexplate and headers.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Originally Posted by UltRoadWarrior9
Today, I adjusted the lash on the T&D 1.6 rockers. The CompCams short travel lifters spec'd a 1/4turn. After I was done, there's no interference between the 5/16" pushrods and AFR 210 heads like there was with the 3/8" pushrods, still very tight clearance. Looks close to .030"...
I decided to go cheap for the ignition system and go with GM HEI only in order to get this thing started quicker.
Just ordered a 7730 ECM (EBL P4 FLASH) from DynamicEFI, a 1992 Z28 HEI distributor from Rockauto and 8.5mm MSD superconductor wires and loom kit from Summitracing.
I'll need to focus on finishing the engine running stand next. I had to cut sections out to make room for the flexplate and headers.
I use a regular heavy duty engine stand and an ICT chevy mounting bracket to run my engine on. Use a water hose for engine cooling. My 383 is getting run in with a 600cfm Edelbrock and a TBI distributor.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Originally Posted by UltRoadWarrior9
Will weld in some square tube to mate the bottom of the stand and bolt to the engine dowel pins. Will not be straight tubing is in the previous pic.
You are going way over what I do. I have a wide based 2,000 lb engine stand. I have an ICT Billet chevy adapter plate. I fit a TBI distributor and coil on it without the EST connector plugged into anything. I fit a edelbrock 600 cfm on it. I use a set of shorty headers I have kicking around with a pair of glass packs clamped to them. I have a random truck water pump and V-belt pulleys. I found a belt that fits reasonably well and roll the belt on with a large flat blade. I have a marine water hose that connects to the water pump and the thermostat housing together. I have a 5/8" heater outlet on the intake and connect a section of hose to carry the hot water away. I use a ball valve on the heater inlet and connect a garden water hose to it. It actually takes suprisingly little water to keep it cool I have a cheap 2 gauge panel with a mechanical oil pressure and temperature gauge. Finally I use an aftermarket mechanical fuel pump that draws fuel from a 6 gallon outboard boat fuel can I borrow from one of the boats.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Hey, thanks for posting! I have a goal of learning tuning with a EFI setup. You seem to be using carb in order to check for oil/coolant leaks and maybe other issues, like me but... Me, I am actually very worried about the 42lb/hr injectors spraying too much fuel and doing damage to the cylinder walls with the initial ECM programming.
My goal is to have this thing running decent on the stand at home, then I bring the engine to work and transplant it into the IROC and drive back home under ECM control.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Make that 8qts of Rotella 15w40. Installed an oil pressure sending unit meant for the 1986 instrument cluster. Screwed right into the '880 block. Primed it tonight with the Summit oil primer shaft and drill. I'll upload a video when it's finally done processing by Fing google... Compression test is next for all cylinders.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Made another video...
This one includes me firing up the IROC with a ministarter that was previously installed. It's a totally different unit than the LT1 starter I chose for the 383 build, due to header clearance issues I was having with the ministarters. You can hear it's turning about 2x faster than the LT1 starter that is on the 383 build, if you listen closely...
So far cylinders 1,3,5,7 are measuring 150psi +/- 5 psi. I was expecting more, but this 292XFI cam has serious overlap. The exhaust and intake valves are barely closed for any amount of time during the compression stroke. But I was seriously liking the compressed air going by my head out of bank 2. Will measure cylinders 2,4,6,8 next.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
The engine is finally going in. With work being slow, I have a unique opportunity to finally install this 383 in the car at my shop. Pre-testing it running on the stand had to be skipped. Tomorrow the TH700R4 goes back in. Thanks to GTAMatt who sold me a Vigilante torque converter with a stall speed of about 3300-3500. That was some short notice and he came through!
Here's some pic's of the progress from the garage to the shop...
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Your build has taken even longer than my own!!! I’ve been at it since 2016 and while still going at it it has at least been on the road. Switching over to FI from carb has been my latest and still working out a couple bugs.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Originally Posted by SilverChicken
Your build has taken even longer than my own!!! I’ve been at it since 2016 and while still going at it it has at least been on the road. Switching over to FI from carb has been my latest and still working out a couple bugs.
Yep, I was on course to start the engine on the stand at home and check for leaks, start a basic tune, etc... After this chronovirus thingy hit, our shop has had enough dwell time for me to jump in and take advantage of that dead time and put the engine in. Currently in a hold pattern, as the TH700R4 is being rebuilt for 500HP by a friend of mine. By this weekend I'll have the trans in, headers on and 99% of the wiring harness done on the '7730 EBL P4 Flash to 383.
Tomorrow, fuel fitting adapters and fuel pressure regulator come in...
BTW, the cowl hood in my sig, does actually fit over the intake elbow! Whew! I'd estimate 1/2" clearance. This is with the original motor mounts...
Last edited by UltRoadWarrior9; Apr 15, 2020 at 03:04 PM.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
Past 2 weeks, I've completed the engine swap from original 305 to the 383, completed the fuel system, serpentine belt system, coolant system, installed the rebuilt TH700R4 for 500HP along with a Vigilante 3200+ stall speed converter, installed the stainless longtube headers and mated it to the old summit catback system, cut out 90% of the old wiring harness and installed the new harness from Harry's Electric, and mated it to the EBL P4. Hooked up the laptop to the EBL P4 and successfully reflashed just a few critical variables like injector flow rate and cylinder cubic inch size. More tuning definitely needed, but here's a pic and video. I was guessing at the distributor advance and I actually must've gotten lucky!
Last edited by UltRoadWarrior9; May 8, 2020 at 05:20 PM.
Re: 383 GEN I SBC Build. 500HP goal... (Can I retain the TPI Intake?)
To all the guys that have posted their knowledge and comments on my thread, today was payoff day gentlemen! There was over 10K invested in this engine build and your input was weighed and was found to be extremely valuable, it is much appreciated! Today I drink a few beers and relax. And think... And read... And... the hood still closes, with a few mods.
Last edited by UltRoadWarrior9; Apr 28, 2020 at 03:33 PM.