johnf123

so I purchased the base GM 350 engine most of you may have seen on Jegs, the 1500$ one. and I will be upgrading this engine before it goes in my car with all new parts, so I do not have to use the old engine.
Things I plan to do:
Jegs mini starter
MSD distributor
Big ***** Thumpr cam
Cloyes timing
Comp rocker arms?
Ram clutches flywheel?
Hooker headers
Jegs alternator
stock 700R4 to T5
new F.I. setup

SO my question is..
1. are these worthwhile upgrades?
2. the engine before was a 305 TBI, is there an easy kit to buy to convert it to a TPI, or am I stuck with tbi.I found a Weiand kit on Hawks but i dont know.

3. if i am stuck with TBI, will I benefit from a Holley 4 BBL tbi? thanks alot this is a handful for me

T/Aperformance

OK first. Whats the cam spec?
what heads are on the engine? cc? valve size? ect.
what are you planning to use the car for ?
Whats your HP goals?
And for the efi its self I'd suggest a self tuning from holley or something.
And I would rethink your trans swap. A t5 will not like a lot of HP. maybe look for a t56

scottishtransam

I agree with the post about the t5, I chewed mine up in my formula with only minor mods. Wasn't that why gm never put them in the 350 l98?

johnf123

Cam: stock Hydraulic flat tappet cam (.383''/.401'' and 112° lobe separation)
Thumpr: HYDRAULIC ROLLER Street/strip, needs 9.5:1 CR , 2800+ stall, intake, gears, and headers, very rough idle

Heads: Stock Cast iron cylinder heads with 76cc chambers

Complete engine specs, stock 350 Engine Specifications

4-bolt main with 2-piece rear main seal
Cast iron crankshaft
LT1/LT4 powdered metal connecting rods
Cast pistons (dished)
Hydraulic flat tappet cam (.383''/.401'' and 112° lobe separation)
Cast iron cylinder heads with 76cc chambers
8.5:1 compression ratio
Block is compatible with left or right side oil dipstick (Requires Plug for Unused Side - Plugs are Included)
4-quart oil pan
Timing tabs for a 6-3/4'' or an 8'' balancer
Recommended spark plug: Accel #111-574 or any spark plug with 14mm .460'' reach, 5/8'' hex, tapered seat, projected tip

johnf123

Is there a special manifold or a kit i can buy for tpi?

scottishtransam

I love TPI but unless you already have it there are better options, you'd need the hole setup- manifold, runners, plenum etc, not to mention the wiring harness issues, that cam that came with the motor seems really tame. Good luck

Jim85IROC

iTrader: (2)

That motor isn't going to give you much to work with. The heads are crap, the pistons are dished, the block is a 2 piece RMS block, and it's got a flat tappet cam. I think you're much better off finding a low mile l31 out of a 96-98 Silverado or van. Then you get vortec heads, a roller cam, and a 2 piece RMS block. That motor has way more power potential, and will get better fuel economy too.

johnf123

Should i just stick with a 4 bbl tbi then?

Jim85IROC

iTrader: (2)

the induction isn't the problem, it's the motor. It's going to suck no matter what you put on it. TBI will be perfectly capable of feeding what that motor is capable of.

vetteoz

iTrader: (13)

If you decide to go with that engine ,read these articles on how to put some life
into that base GM engine
New heads to get more compression a minimum

http://www.chevyhiperformance.com/te..._ii/index.html
http://www.chevyhiperformance.com/te...iii/index.html
http://www.chevyhiperformance.com/te..._iv/index.html

mmadden55

Fuel injection is the b etter option but it costs, best bang for the buck is edelbrock air gap and holley 780. I would alumium heads and a hydraulic roller cam as well.

vetteoz

iTrader: (13)

As already noted by Jim85IROC
would be more effective and cheaper in the long run to sell that low comp crate engine
and start with a better base

Roller lifters to convert a flat tappet block are $300+ without the cam cost
That $$$ would be better spent instead on a roller cam block

Jim85IROC

iTrader: (2)

An RPM airgap and a 780 is all wrong for that crate motor. You might as well put a 1050 Dominator on a 305. A 600 Holley with a Performer intake would be a much more appropriate induction combo for that crate.

johnf123

upgrading the heads with RHS, not sure which ones yet, the timing is gonna be a gear drive no belts or chains, a thumpr hydro roller cam and comp rocker arms. so 4 bbl TBI or tpi swap?

Jim85IROC

iTrader: (2)

Forget about a gear drive with efi. Knock sensors don't like gear drives. A double roller is perfectly adequate.

johnf123

Then a double roller, and i found a guy whod sell everything for tpi including the harness for 350$

johnf123

how about a belt drive? i want that whine you get with gear drives but like you said they dont work with the knock sensor

85T/A350

I've read some bad reviews on the thumpr series cam. Some say its only for sound and not so much for performance. Is that motor a roller motor?

johnf123

no hydraulic

Jim85IROC

iTrader: (2)

Saying it's hydraulic doesn't answer the question. Is it a roller block or flat tappet block?

Belt drive will be fine. A waste of money, but fine.