Needing advice for a build

Logan · Jun 30, 2012

OK, so I am pretty wet behind the ears when it comes to SyTys. I have my Typhoon and got royally screwed on it. I got it home with a horrible knocking sound, power loss and it stumbles after about 2800 rpms. After I checked the compression and all 6 cylinders were at approximately 88 psi I decided my engine is probably trash. I am gonna mothball the original engine and maybe build it back later. I am getting an early 90's block, L35 heads, forged pistons, chrome rings, billet mains or possibly upgrading to 4 bolt and I will get the block, heads and crank cleaned up at the machine shop but what specifically do l need done?
My big question is where do I go from there?

My budget is about 2000 give or take and I want a solid running engine that is reliable and around the 300hp mark. I want to build it to drive, not to race but of course I want to be able to break a few hearts between the stop lights. Right now the mods that are done to my truck are the Ultimate chip with Gauge style display, injectors with a lime/pea green ring? possibly 42lb?, EGR delete, unknown set of headers, no cat, aftermarket manual boost controller underhood and that is all I have identified so far. My question to you guys since you are saltier than I is what should I look for as far as cam set up, any good pointers, things I should change, do or fix? I am wanting to get the parts and guide a shop through the build since I am finishing up my tour in Afghanistan (home in December, Thank God!). Any pointers you guys can give me would be greatly appreciated.

T-Bone · Jun 30, 2012

Re: Needing advice for a build

I detest sellers who do not disclose issues completely and thus deceive buyers.....especially when the buyer is a fellow comrade in arms.

Sending you a PM !!!

Logan · Jun 30, 2012

Re: Needing advice for a build

The best part is I picked it up the first day I was home on leave. I flew to Chicago to get it, got off the plane still in uniform and went directly to pick it up. The ad said it was pristine, one of the few that hadn't been driven into the ground, etc. etc. The second I took it I knew something was wrong but he left as soon as I did so I took it easy home and made it safe but then I emailed him and explained what all I had to do to it and asked if he would simply help, I didn't expect much and got less than that. The guy won't even return my email so I may pursue it further but again, buyer beware. He has another Typhoon for sale, it is yellow and he wanted a little more for it, I hope whoever ends up with that one doesn't get hit like I did.

sharkbait · Jun 30, 2012

Re: Needing advice for a build

where do you live (when not fighting for our country)..........and thank you for that.

dgoodhue · Jul 1, 2012

Re: Needing advice for a build

Our truck use a map sensor based fueling system. Map sensor system do not do well when the air flow of the engine is changed because it does not detect air flow changes just pressure changes. Basically putting just set of L35 heads that flow 10% more and running 15psi, the computer would fuel it the same way as a stock head running 15psi. Map based systems generally don't do well when some SyTy's throwing performance parts at an engine.

Different cam and heads from stock pretty much require a custom tune. If your not planning on doing code59 or finding someone to tune your truck stick to stock heads/cam. If you do have 42# injectors the ultimate wasn't made for them and it also would cause a bunch of drive ability issues, different injector have different linearity, so you often you cant just change the fuel pressure or injector constant in the chip The Ulitmate chip only came in 50 and stock versions. Again if you pick a different injector than the chip was tuned for, it should have a custom tune.

Logan · Jul 1, 2012

Re: Needing advice for a build

sharkbait I am stationed at Fort Leonard Wood, MO but I am from Oklahoma. Thanks for the support. I can't say it is too noble though because the extra pay is funding my Ty project.

dgoodhue thanks for the info. I have been reading everything I can get my hands on and tuning seems to be a recurring point for these trucks. I have never messed with much tuning other than my motorcycle. I have a few questions to make sure I have a solid grasp on it if you could answer them I would really appreciate it.

1. If I put 50 lb injectors in with the Ultimate chip will that cause a rich mixture or flooding? Or does it allow more fuel when needed i.e. under load, WOT, etc.?
2. When people talk about the tune that is in the ECM which works in conjunction with the chip or one is actually reprogramming the chip? If that is the case would it be better to go with a different chip? I have what appears to be the factory chip and another that looks similar to it but it has a Kenne Bell sticker and part number on it. They were in the center console when I bought the truck.
3. I believe (maybe) that this truck has the three bar map sensor as the boost gauge is wildly inaccurate, it reads in the negative side which to my understanding would mean the engine is creating vacuum while at idle and all the way until about the 2000 rpm mark at approximately 40% thottle then it reads between 5 to 9 psi. So is that good to stay or should I attempt to go back to stock and start from there.
4. Are headers really worth it with these trucks? I know they are outrageously expensive so I am not looking to get rid of them but if the stock exhaust manifolds would perform as well or better with the setup I am currently looking at I would prefer to go back with that and save them for a more wild build once I get more confident with these trucks.

I think my biggest issue is not knowing what all was done to it before I got it and so I am having to guess on too much. Another random issue is a purple wire that runs in the split loom on the firewall high on the drivers side is cut? I don't know what this wire goes to or why it would be cut. Also there is a single white wire with a factory looking pigtail under the passenger side dash that is unplugged but I couldn't find where it was supposed to be plugged into. My thought on it is if GM and PAS to the time to put it in it probably serves a purpose so could you or anyone for that matter shed a little light on those two items. Thanks again guys, I learn more and more everyday but most everyone here seems to be way ahead of me on these trucks.

gstacky · Jul 1, 2012

Re: Needing advice for a build

The purple wire is for your starter. They are a common problem with these trucks and someone likely spliced it there and ran a new larger gauge wire to the starter.

As for the white wire, it's more than likely one of the dome light grounds that works off the door jam switches, and might tell you that the dash has been out and someone unhooked it and never plugged it back in. The other end should be there somewhere near the power window/lock harness.

Hope this helps, good luck getting the truck running again. And if you don't know how to tune, rebuild the original block back to stock for now, and build the other one up at a later time when you have all the parts together.

Logan · Jul 1, 2012

Re: Needing advice for a build

Thanks for the help. I will chasing this stuff down once I get back and I am really debating on going back completely stock and then working from there. It seems counter productive but I would be happier with a truck that runs and makes 280hp than one that never runs but "has potential"

Jimmy · Jul 1, 2012

Re: Needing advice for a build

2 grand isn't gonna get much.

I'd find a running 96 up Vortec motor and get your stock lower intake modded to fit and use all the stock Sy/Ty parts you got.

Get a 255 Walbro,an ajustable FPR,a boost and FP gauge,and Datamaster for now.

That's 2k if you do all the work.

Logan · Jul 1, 2012

Re: Needing advice for a build

Thanks Jimmy. That is one avenue I have been looking at but I am hesitant to do any type of permanent modifications to the Ty specific stuff. I do have the adjustable FP regulator so I am almost there. lol. I figure my budget is shoe string to say the least. I may end up spending more just because I want to do it right the first time and not trim corners. I have a line on a pretty nice engine right now so I am waiting to see how that plays out. I am gonna go with your suggestion on the Datamaster. I have been diving into all of the tuning info I can find and like anything else I am sure I will continue to learn on that too.

Quickstop [UK] · Jul 1, 2012

Re: Needing advice for a build

The wire under the dash - is it def White? There's a tan wire that should be connected that controls your timing and that won't help if it is disconnected.

Have you got a CEL light at all? Does it come on when you start the truck?

Headers are the last thing you need. People are in the 10s with stock ones I believe.

The Kenne Bell is a Kaboom chip also. Sell it!

You would be better with the vortec motor IMO. You'll need tuning stuff (Ostrich etc) anyway but the vortec gives you more leeway later.

The tune can be 2 things - a custom chip plugged in or an emulator which is the Ostrich. You just programme from your laptop. Much better.

If you plug in 50# injectors, you need the 50# ultimate tune or it will flood and misbehave. 50s are notoriously variable so you might want to hold off them and consider just running stock for now.

I was in the Army and about 25 when I got my truck with a tonne of problems. I too went on tour to pay for it

Good luck!

Logan · Jul 1, 2012

Re: Needing advice for a build

I hate Afghanistan.....I had a reply typed up and then the internet dies. Anyway.

Quickstop, thanks for the pointers. I am gonna take your advice and go with the ostrich as far as tuning and management. I think my plan of action is going to be putting the truck back close to stock as possible. A few upgrades like the heads but not vortecs. I just hate to think of modifying that intake. The headers are gonna stay because they can't hurt and I have a line on an engine right now and if the numbers are right it is gonna be calling my Ty home.

I do have the CEL and it functions I got a code off of it before I left and it said rich mixture determined by oxygen sensor. I am fairly certain the wire is white but you may be right. I know that wire you speak of deals with advance in some form but I couldn't find a socket to save my life under the dash. I had the dash out for a heater core replacement.......another story of its own though I have had experience with that project. Thanks again for the info and I am certain that I will have many more dumb rookie questions along the way.

Jimmy · Jul 2, 2012

Re: Needing advice for a build

The only thing you will have to modify is the lower intake manifold.And by modify I mean just adding more material to it.Not a big deal.

And it's the cheapest way to go.

Quickstop [UK] · Jul 2, 2012