Hey guys I am new to the site and I have looked around for a few days and have not seen any specific answers for the questions I have.

A little background; I am looking at purchasing an '88 iroc with 350 and TPI. From what I have read these make 230 HP and 330 TQ. I know that it may bother a few of you but I am buying this wrecked car to take the drive train (engine and trans only) and put it in a 74 Chevy Cheyenne Super C20 Crew Cab Long bed. I have already got a Dana 60 front axle, NP205 with th350 adaptor and corporate 14 full floater rear. The truck will be lifted 6" with 37" military type tires and has a 4.10 gear ratio. The original engine is a 454 Big block (low compression) and I am hoping to get overdrive (with lockup?) as well as a smaller cubic engine (Less weight, better mileage) with cold start reliability (EFI) I live in California so we have crazy emmision laws on cars 1975 and newer, which is the reason I am even doing this to an older truck to begin with.

So the few questions I have are:
Are the 700r4 transmissions in the 88 Iroc Computer controlled or cable controlled?

What is the least expensive way to get the 350 TPI system to 350-400 hp or close to 500 ft/lb TQ? (either stroke increase, heads, headers ect?)

Do i need to retune the ECM for 37" tire size with a 4.10 rear end ratio or will it continue to work on stock settings?

Thanks for your time and patience, I am sure these questions have been asked before I just couldn't find them on the forum.

If u want more power by modding the engine us gonna have to tune it anyway ...

91' bird 305 TBI T-5, trick flow 175 cc heads, 4.10 gears, lots of suspension upgrades. 24mpg @ 2500rpm hwy. 8.80@ 84mph 1/8th on street tires... 8.000's soon

I don't mind tuning the Chip after the install is complete I just want to make sure I go in the right direction before I start buying parts. Also if its not a good fit I would rather got for something different completely. I see threads on here where people are putting 6500 rpm max power cams on a tbi system that cant handle over 5000 ect. I dont want to be that guy so I'm am asking for suggestions before hand. I am looking for the least expensive combination of upgrades to get to 500 ft/LB TQ or 400 HP and still be able to drive around in the city and highway.

Does anyone have any experience making reliable horsepower/TQ from these engines that could chime in?

Actually the tpi system is the one that's gonna limit upper rpm HP not TBI ... I shift my TBI setup at 6k all day long ... And IMO TBI would b cheaper and better for a 4wd truck ... To get to 400hp from tpi ur gonna need a decent cam , some port work on the intake runners and base , or aftermarket base and runners, port heads or get some vortec heads or aftermarket, I would up compression to about 10:1 for iron heads or 10.5:1 for aluminum , ..... Or just slap a procharger on it with a good tune and b done with it ....

For 500ft lbs all the above plus some more cubic inches ... So 383 stroker crank

91' bird 305 TBI T-5, trick flow 175 cc heads, 4.10 gears, lots of suspension upgrades. 24mpg @ 2500rpm hwy. 8.80@ 84mph 1/8th on street tires... 8.000's soon

Awesome that's what I was hoping to find out. When I said TBI had a limit of 5000 that was a typo I meant TPI sorry. Also does the 700R4 on the 88 model have electric controls or are they cable controlled? Does it have a lockup Torque converter? I am willing to get Vortec heads, Cam and Crank with headers ect but I would rather not get into porting runners, heads or anything that takes a large amount of money or time. I figure I will already have to tune after the fact which could be somewhat of a PITA.

With vortec heads, Cam and exhaust on stock TPI system (tuned injectors ect.) what am I looking to get HP tq? no porting ect.

Thanks for the replies so far I'm testing the waters to see if this would give me what I want.

The trans does have a lockup and IS controlled by the ecu as I'm using the EBL flash for tuning my TBI 5 speed and it has all the parameters in tunerpro for tuning your lockup rpm shift points etc. ...

I'd say stock TPI, stroked to 383, .030 over ,at 10:1, with good vortec heads with 2.02/1.60 valves ,with a good aftermarket vortec TPI base , good longtube headers, let's say around a 212/218@ .050 cam on a 112 LSA and .500 lift , good ignition system , good oil pump , good valve springs, etc. U could port match everything before u take it to the machine shop as far as the base to heads base to runners runners to plenum plenum to TB ... All it takes is a dremel with a carbide cutter some sandpaper rolls a little time and attention to detail ! There are numerous threads on how to get ALOT more flow out of the TPI stuff .. And u HAVE to buy a vortec base if ur gonna run vortec heads which ain't cheap


With stock TPI Prolly 350HP @ 4500-5000rpm and 450ftlbs @ 2200-4000rpm mabey more .. Idk much about tpi I'm a TBI guy lol

91' bird 305 TBI T-5, trick flow 175 cc heads, 4.10 gears, lots of suspension upgrades. 24mpg @ 2500rpm hwy. 8.80@ 84mph 1/8th on street tires... 8.000's soon

If you were going that direction you would buy the Vortec version of the HSR that has far more potential than a TPI

$400 for the Vortec base required to keep restrictive ( on a 383 ) stock TPI

https://sdparts.com/index.php?q=deta...-center/sd3816
Extra $470 for big tube runners
http://www.summitracing.com/int/part...3865/overview/

whereas $670 for a HSR setup puts you in a whole different ballpark

http://www.summitracing.com/parts/WND-7542/
http://www.summitracing.com/int/part...-186/overview/

Cheaper fuel rail alternatives here
https://www.thirdgen.org/forums/alte...tive-fuel.html

TPI Intake comparison here
http://xtremecarzone.com.au/index.php?showtopic=386

The TC lock up yes, but not shift points, shift points are controlled via the TVC, and should be adjusted (for longevity) to spec.

To the OP...what are you building the 4x4 for?

I/e mud bogging, fun, climbing...etc, etc...

No use building a motor that's good to make power to 6500, if you're not going to use it.

I am building the motor actually for hauling a 30ft toy hauler to (around 200 miles) and through sand dunes, Collecting firewood in the fall and winter when it may be muddy or have snow/mud on the ground and hauling my flat bottom boat to the local lakes during the summer. I live in the mountains @ the 1500Ft level but the truck will also be going to 8,000ft elevation at least once a month. I like the Fuel injection so it can adjust itself to atmospheric conditions. It would possibly be used for 4WD in summer months on fire roads and small courses. Sand play @ the dunes would happen once the trailer is disconnected. I don't expect to get mud to the doors or crawl over boulders.

Some goals are to have a pre-smog truck that at least matches performance of modern day trucks so i don't feel like a tool climbing the mountains @30MPH. The truck used to have a 454 low compression engine and now has a stock 2 bolt chevy 350 that is gutless and weak for the size of the truck. (Its also probably pretty worn out) The Camaro I am looking at has 109,000 miles and looks mostly stock except that the interior is wrecked beyond belief and someone started to do the swap and gave up for whatever reason after disconnecting ac lines and a bunch of random stuff.

I should say that I am hoping to make as much power down low as possible and I would like to make my power right at 3000-3500 RPM with plenty of torque down low to get everything moving.

Thanks for the replies I am picking up a wheel dolly to move the car to my house today.

Are the rear drive shafts just 4 bolts on the u joint and a slip joint? I don't want to tow it 40 miles with the drive-line in it.