Hi guys. The 305 in my Iroc is getting kind of tired, my original plan was to rebuild it and do some minor mods on it to try to keep the project cheap, but after thinking about it alittle more I'd rather spend the extra money and go for a bit more power. So I started looking around at different crate engines and the prices on 383 long blocks has me tempted.

I've built a few engines and have quite a bit of mechanical experience but to be honest this is my first time around anything fuel injected. Never touched anything newer than the 1976 350 in my truck. I really want to keep the TPI even though I realize it has some drawbacks I'm kind of looking forward to playing with it and learning all I can about it so the option of slapping a carb on it isnt something I wanna do.

My question is how compatible is TPI with the 383 crates I see?
So far the engine builder I'm thinking about is Gustaf Engines I've heard alot of good stuff about them and it's close enough I could go pick the engine up to avoid shipping. More specificly I'm interested in the super street Torque Monster 383.

Will the TPI intake bolt up to the heads on that engine? Also how will the TPI get along with the cam?

I'm pretty much open to advice here... If you guys know of 383 crates that'd go better with the TPI than this one please let me know. Also almost all crate engines I see with advertised HP and Torque are dyno'd with carb's on them... how much difference would there be with TPI instead?

sorry for so many questions, I really dont know much about the later generations of SBC's.

Thanks in advance for your help

Paul J.

 

383 run great with TPI, lots of torque, but there a little tricky to
set up. Its important to use a cam designed for computer controlled engine. with a wide lobe angle 112 degrees and not
much overlap. then you will need to change the injectors to
24-30 lbs and a adjustable fuel pressure regulator. and then
find someone to calibrate the fuel map for your engine. is your
TPI a speed density or MAP system? good luck.

 

The only thing that is bad about the tpi is that it runs out of breath at about 5000 rpms. This is why a lot of people switch to something like a holly stealth ram or even better a tpis mini-ram although not too many people go with the mini ram due to the 1300 dollar price tag for intake and fuel rails but it is the best thing you can buy.

and to the previous post and anyone else it should be MAP because they switched to speed density in 1990 and his is an 89.

 

Will the TPI intake bolt up to the heads on that engine?


The TPI requires heads 1987-1992 with the center bolts canted
check with your builder to see which heads he is using. or I think you can you can have your TPI modified to fit earlier heads.

as a earlier post the engine will be a torker and run out of steam
at about 5000 RPM but wil be a lot of fun to drive and a great
street motor!

henry

 

Centerbolt heads are just for the valve covers. The intake manifold will fit any old regular heads (w/ exceptions such as Vortecs). Someone correct me if I'm wrong.

-Rippin

 

The TPI requires heads 1987-1992 with the center bolts canted
check with your builder to see which heads he is using. or I think you can you can have your TPI modified to fit earlier heads.

as a earlier post the engine will be a torker and run out of steam
at about 5000 RPM but wil be a lot of fun to drive and a great
street motor!


I am not referring to the valve cover bolts but the two bolts
by the heat risers on the TPI manifold. they are drilled at a
different angle than standard early heads. and they a both
different than the vortec heads also.

Henry

 

Thanks for all the replys guys. I'd read about the TPI's running out of breath at 5000 before but that doesnt really bother me, I'm lookin more for a fun street car that'll lay down some rubber when I want it to, So I'll probably never need the higher RPM's.

If I get the 87-92 heads will all my stock accesories bolt up to them? Valve covers, AC brackets, alt brackets ect? I'd like to make the 383 look as stock as possible. I've got an old laptop and plenty of time to learn so instead of having someone burn me a chip for the ECM I'm thinking of trying it myself (with plenty of help from the good folks here and at 3rdgen.org)

The hp/torque numbers I'd like to see out of this car is somewhere in the neighborhood of 350-400hp and 400+ torque, I know thats not a problem with a carb'd engine, will the TPI get me those numbers?

I appreciate all your advice guys, I owe ya one

Paul J.

 

all your accessories will bolt up to the 87-92 heads just make sure you get 350 heads and not the 305s.

henry

 

yea, 350-400hp should not be a problem. you may need to port
the plenemum and get the large runners. and 58mm throttle body. it will run good!

henry

 

if you have a motor built use a late model hydrolic roller cam block. 1988- present. they make more hp.

henry

 

Accel makes a manifold that has slotted bolt holes to retrofit new and older heads. I would change the heads and intakes and use 26 pph injectors and forget the AFPR. Just get someone to flash the EPROM for you and you will be set. See my sig on who to contact for free advice on what to do and they will also burn your EPROM and it will be custom. They burn the first one to your specs and then the 2nd and 3rd one based on your readings from the ECM. That will get it dialed in just right.

 

Are all 2nd generation blocks set up for roller cams?

also what company makes a good Iron roller block?
any recomendations for heads?

I still kind of want to build it from scratch myself, just because I enjoy assembling engines.. I've got the tools and the knowhow but the cost of a prebuilt short or long block seems cheaper than buyin the parts seperatly and most have a warrenty

I plan to baby the 305 til late fall and do the engine swap in november/december

the car has almost 195,000 miles on it now and we've got a trip to texas planned in october so she'll be over 200k by the time I get the 383, not bad for a 305 hehe.

Thanks again for the help guys
Paul J.

 

Are all 2nd generation blocks set up for roller cams?

also what company makes a good Iron roller block?
any recomendations for heads?


No all second gen block are not set up for roller cams.

bow tie block are a good choice with one piece rear main seals.
it all depends on your buget. it might be a good idea to get
a short block assemply. with 5.7 rods, forged pistons, balanced,
$1500-2000, top it off with vortec's ($450)or Dart 200 cc iron eagle's ($850)
and a LT-4 HOT GM cam.($175) reuse your roller lifters, guide plate, and cam retainer. you will have a good driver and about
375-400 hp.

note: if you build it your self there is some fitting to do for the
stroker crank to fit the 350 block, and you have to have the whole assembly rebalanced damper, crank, pistons rods, flex plate. the 383 uses a modified 400 crank (3.75 stroke) which is
externally ballanced.

so it might be a good idea to buy a short block all set up.
add the heads, cam and your injections system.

henry