cabech984

I am in the process of rebuilding my 350. It is a 2 Bolt from an 87-91 Full Size Truck. I am using an eagle cast crank(3.48"), eagle connecting rods(5.7"), hyperutectic flat top pistons (.030) and a comp cam with stock heads & rebuilt valvetrain with 1.5 ratio rockers. I should be around a 9.4 / 9.5 to 1 compression ratio and am using the TBI from the pickup it is going in. The Cam Card is as follows;

Intake Exhaust
Lift Lift
.447 .462

Duration
I E
210 218

Lobe Separation Angle
111.0

I am putting this engine in my 95 Chevy C1500 Pickup 2WD, 4L60E, and 3.08 rear end gears. I am not concerned with making max power but I would like to know what it might make. Also, will I or should I get my tbi tuned? Howmuch does this usually cost to tune?

michal_larson

power is a theoretical construct. it is what you make it to be
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those cam specs look like the zz4 camshaft or close to it
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TBI fuel injection is a different breed, but the same animal. what else cn i say, dynomite comes in small packages
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TBI is like the ancient indian game, just shoot it in da hole.

michal_larson

you dont talk much.

Irockz

iTrader: (1)

I'm guessing he don't want to deal with your dumb ***.
You told him nothing,just talked a circle of shat.He needs real knowledge,which neither you or I can provide.The difference is,I'm not pretending I can.

Fast355

iTrader: (2)

Is that one of the Comp Xtreme 4x4 cams?

88-383

I just got my 355 runninng with CNC TF heads, and 219@.050 10.1 compression. Mine is going into a 1990 K5 so our goals maybe similar. I can tell you right now, You need to learn to burn your own chips!

Mine started and idled ok with the stock chip, but my nose and wbo2 told me it was way lean, and as a result it hasn't left the driveway yet. I just finsihed getting a chip very close with 75# injectors and it seems like it's ready to go. I still have a lot of tunning to do, but I think it's safe to cruise to the dyno shop for a full on loaded tune.

I'll post back when it's all done! I'm not expecting the engine will operate at it's fullest potential because of the TBI manifold etc... But I'd like to see atleast 300fwhp and 350ish +/- for torque with a fairly broad powerband. My Edelbrock manifld was ported and gasket matched, I've also got all the TBI bores/mods etc..


Kelvin

Gunny Highway

iTrader: (1)

With Trick Flow heads, a cam (204/214 .429/.452 116), 1.6 RR's and full exhaust I made 262 RWHP and 365 RWTQ with 55# injectors.

Fast355

iTrader: (2)

This is exactly the TBI potential that I have been preaching for some time now.

Now imagine if you had a cam around 224/234 .480/.500 lift, 110-112* lobe seperation, a performer RPM spreadbore intake, factory 454 carb-tbi adapter, 454 TBI and 454 injectors or 61# 350 injectors at like 35 PSI, and the tuning to run it. 300+ RWHP TBI.

The factory TBI intake and TBI are not a restriction until around 325 FWHP with the addition of a 1" tall open TBI spacer. Without the spacer they start becoming a restriction around 300 FWHP. I have watched the spacer add 5-7 KPA of MAP to an intake running at around 5,500 on a 340 FWHP 350 (279 RWHP). 92-93 MAP @ 100% TPS before and 97-100 MAP @ 100% TPS and the same RPM.

Gunny Highway

iTrader: (1)

It has the Edelbrock TBI intake that has been bored out to 2" to match the 2" throttle body. I do have some 65# injectors, but it turns out I didn't really need them. I still have no lean issues at all with the 55#'ers.

However, I'll be honest, I don't really understand what you're getting at with the TPS stuff.

88-383

Wow, so it seems my estimates were on the conservative side. I'm glad to hear more pwr can be had. Now I just gotta figure out this dayum chip... Are there any local N.CA TBI guys out there that can mentor?...


KM

Fast355

iTrader: (2)

The TPS stuff is just what I observed through dataloging, before and after an open center 1" TBI spacer installation. Without the spacer it generated a healthy vacuum, with it the vacuum was greatly decreased. I noticed a dyno improvement of 5-7 HP with the spacer and noticed a loss of 5-7 HP without it.

Gunny Highway

iTrader: (1)

The chip tuning is really the key to unlocking all the power of these things. Although on my just datalogging chip done by TBIchips.com I made roughly the same peak numbers (albeit, Brian was trying to tune the car when the tranny was puking), the curve wasn't very smooth. I was then able to get it to a dyno and smooth out the A/F ratio and that's where it came together. I picked up about 12 peak RWHP, but the "peak" was now a plateau from 4700-5700 RPM's. Not to mention I picked up about 15-20 RWHP across the entire band. It's was nice not having to go to bigger injectors and start all over. I have no lean issues at all on the 55#'ers.

The only thing now is I have a slight surge at idle when she's cold and a slight surge when I'm coasting at highway speeds. Other than that, she's all ironed out and I'm happy with it.

. . . maybe some juice for it later though

DM91RS

cabech984

Yes it is PN 12-235-2. I hope everything works out for it.

my1st88camaro

well cabech984, you and i have almost the exact same setup engine wise! except i did a little head work which you seem to not have done and i have 10.5 comp. my cam has a duration of 214/214. i also have 4.11 rearend gears. so mine is probably making more power then yours will at the moment. (i'm in the process of installing a rebuilt racing 700R4 w/3000 stall converter and pretty much rebuilding the entire engine other than the bottom end and carbourating it). numbers wise i cant help you because i have never dino'd my car. but i can tell you what to expect performance wise and what should be done to help pick it up. first your engine will have a good amount of torque more then hp because you went with stock heads and probably the same stock int. manifold and throttle body. i'm sure you probably have the same stock exhaust too. the reason why is your stock head/intake/throttle body/exhaust setup is WAAAAAAAAY to restrictive for the amount of power a 355 wants to make. i can feel it pull damn hard at low speeds but once it gets up to highway speeds it suffers and i can feel it suffer. the next mod i'm going to be doing will be the exhaust to help it breath which will pick it up at high speeds and help the all over efficiency. after that eventually new heads, intake, cam, valvetrain, carborating it and so on. so when you get it in you wont feel a whole lot of horse power especially since you are putting it in a truck, not a car. these are somethings that you need to upgrade to feel the power your engine is capable of. another thing that you should upgrade is your rear end gears. i felt a BIG difference in its taking off capabilities and with its times at the track with them. i have 4.11 gears now and that actually wouldnt be too bad for your truck. you will feel a difference no doubt! time wise my car currently runs around 9.6 ish in the 8th mile and you should expect around 10.5 ish having a truck and lower gears. well i hope i was able to help you in some way. any questions just ask!