Building an engine for Forced Induction?

[Swift_3800_F-Body]

Is anyone here in the process of building an engine for forced induction?

I am unable to find many people that are willing to contribute or take interest in this topic because they are too eager to run forced induction on there stock engine and that is fine but when our engines begin to have problems within the next 20k miles or even sooner we will have to take this topic into consideration.

Now from what i have been researching we can use the L67 short block with our L36 heads.

From what i have researched I have found that 1998 and + L36 Heads are stronger than the previous years. These newer heads may be a good option for porting.

But if you do not want to use the L67 which is not a problem i have been asking around what i can do for the L36 98+ years.

I found for myself its cheaper to buy a L36 Long Block and work from that because a L67 shortblock will cost somewhat alot plus heads from a L36, then if you want to upgrade your pistons and rods from the L67 you will need to balance your crank and other objects to work with the new pistons and rods. Its cheaper to just buy the 98+ L36 longblock, rods, pistons, gaskets, bearings and take them to a quality experienced machine shop for work.

If anyone else has knowledge to share, this would be a good topic to discuss the strength of the L36 and L67 internals for long term use of forced induction.

[slacker69]

Best way to go are to buy the dimanod pistons 8.0:1 compression made by intense-racig they are forged and then get the new rods from the 2004 gtp's they are forged and only cost 31 dolalrs a piece have to machine alittle bit to make them work but nothing big. Have the stock crank hardened and knife edged for wieght removal. Get a set of Total seal piston rings they have no gap and are for boost cause no blowby can occur. Replace all bearings with clevite 77 berings and then use a ARP main stud kit and ARP Connecting rod bolts and ARP Head studs. Drill out a third hole in the intake vally for extra oil.Remove the balancer shaft and block oil hole in back of motor and have all of your internals balenced at a shop. Also get a set of MLS head gaskets they are top quality. Redo all valvetrain with new stuff like compcam 130 lbs springs and low clearence retainers with oil restricted pushrods.

That setup is good for around 28-30 PSI

But you would then need like 72+ lbs injectors and a stand alone fuel system or a low impedence converter box to run the injectors on stock pcm you would need alot of custom programming tio set timing and the injectors. As well as you need a stage 3 tranny with a 4000 stall and gearing around a 3.23

[ September 01, 2003: Message edited by: slacker69 ]</p>

[Tiago]

<blockquote>quote:</font><hr>Originally posted by slacker69:
Best way to go are to buy the dimanod pistons 8.0:1 compression made by intense-racig they are forged and then get the new rods from the 2004 gtp's they are forged and only cost 31 dolalrs a piece have to machine alittle bit to make them work but nothing big. Have the stock crank hardened and knife edged for wieght removal. Get a set of Total seal piston rings they have no gap and are for boost cause no blowby can occur. Replace all bearings with clevite 77 berings and then use a ARP main stud kit and ARP Connecting rod bolts and ARP Head studs. Drill out a third hole in the intake vally for extra oil.Remove the balancer shaft and block oil hole in back of motor and have all of your internals balenced at a shop. Also get a set of MLS head gaskets they are top quality. Redo all valvetrain with new stuff like compcam 130 lbs springs and low clearence retainers with oil restricted pushrods.

That setup is good for around 28-30 PSI

But you would then need like 72+ lbs injectors and a stand alone fuel system or a low impedence converter box to run the injectors on stock pcm you would need alot of custom programming tio set timing and the injectors. As well as you need a stage 3 tranny with a 4000 stall and gearing around a 3.23

[ September 01, 2003: Message edited by: slacker69 ]<hr></blockquote>

\m/ [img]graemlins/burnout.gif[/img]

[Swift_3800_F-Body]

That would be a very hardcore setup indeed very costly but worth the investment if someone were to go for the power.

I dont plan on holding more than 18 psi.

I was thinking maybe doing this

Diamond Coated 8.5:1 Compression Pistons
Total Seal Piston Rings
Series III Connecting Rods
Oil Restricted Push Rods
MLS Head Gaskests
Felpro Intake/OilPan Gaskets
Clevite 77 Bearings
ARP main stud kit, rod bolts, Head studs
Valve Springs 130# w/ Retainers
Custom Cam
Ported Heads

Would that be enough to handle around high boost of around 18 psi or am i going over the top a bit, i dont plan on having anything done to the crankshaft except balancing. The cost is way to high and i dont believe there is any aftermarket ones available. From looking at the numbers of the L67 i really dont think machining the crank shaft is nessessary unless i planned to make some very serious power.

[slacker69]

Yes it would but what kind of RPMs do you plan to shift at cause if anything around 6500 or more i would drill out that thrid oil hole in the intake valley

[Swift_3800_F-Body]

What kind of rpms do you think the Series III Connecting Rods can take?

[Swift_3800_F-Body]

I may not even go 18 psi, my goal is 12's, so if i can hit high 12's or low 13's with 14 psi or around that range i would be happy, then i would concentrate on lightening my car to get the extra tenths, 11's may not be bound for the street, but i would be satisfied with high 12's. I do plan to go with better suspension, to help achieve that, but i am more concerned about my mid to top end considering my low end creates enough decent power to get off the line nicely on street or strip.

I notice how the eclipse GST's have **** for low end but mid to high they keep up and even gain faster than the stock LT1's which is pretty damn impressive for a 4 banger.

Turbocharged cars seem to create horsepower in a quicker way than N/A yet because they get there power quicker it seems. i cant explain it, i will have to read more on the theory. but when my friend races his 3000 pound FWD GST against a 3300 Pound Mustang with slightely rated more horsepower he always kills them in 3rd gear. same with LT1 camaros, his car keeps right with them and even gains on them in 3rd very hard. his car is totally stock except for a muffler.

I know the LT1 and 4.6 mustangs will beat him in the very top end speed of 90 to 120 but for that mid to high end he is somehow turning some serious power it seems.

[slacker69]

With the Seriers III rods and getting the comp cam 130 lbs valve springs and retainers and the oil restricted pushrods you could easyly rev to 7000 rpms thats what the GTPs are doing.

[Ian]

its the same theory as the WRX. How can a 2.0L forced induction car run a 14.1 stock with a good driver when an LT1 can only run a 14.7. 227hp and 22Xtq vs. 275hp and a lot more tq! Answer me that. I know there is a weight difference, and the AWD makes for better launches, but .6 seconds!? I dont think so.

[TheFireChicken]

<blockquote>quote:</font><hr>Originally posted by Ian:
its the same theory as the WRX. How can a 2.0L forced induction car run a 14.1 stock with a good driver when an LT1 can only run a 14.7. 227hp and 22Xtq vs. 275hp and a lot more tq! Answer me that. I know there is a weight difference, and the AWD makes for better launches, but .6 seconds!? I dont think so.<hr></blockquote>

Weight accounts for some of it, but remember, the WRX was designed to compete with our type of cars, so I would not be surprised if it has some exceptional gearing.

The WRX is built much like a 4WD pickup truck. Its primarily a RWD vehicle platform, with a supplementary FWD system. Off the top of my head, I dont know what the gearing ratios are, but I would expect that some aggressive gearing, unlike other cars, combined with a lower weight, would yield very good performance.

In short runs on the street, i do reasonably well against mustang GTs. of course, on the highway, and at the high end of short runs, I get my bumper handed to me on a plate, but the first time I ran against a GT, I was surprised how well my 3800 was able to hang with the mustang. Of course, a 200 hp firebird with a sleeker, more aerodynamic body and 3.42 gears, compared with a less sleek mustang, a 260 hp motor, and 3.55 gears, and its not too hard to see that the overall performance on the street of both cars is not quite as different as you would think.

[nocutt]

<blockquote>quote:</font><hr>Turbocharged cars seem to create horsepower in a quicker way than N/A yet because they get there power quicker it seems. i cant explain it, i will have to read more on the theory. but when my friend races his 3000 pound FWD GST against a 3300 Pound Mustang with slightely rated more horsepower he always kills them in 3rd gear. same with LT1 camaros, his car keeps right with them and even gains on them in 3rd very hard. his car is totally stock except for a muffler. <hr></blockquote>

Although I am inclined to believe that the Gs-T is by no means stock! I will however take your word for it :D

The never-ending debate of HP...Horsepower my friend is an illusion, read up all you want, torque is all that matters when it comes to a race!! oh yes, then there are those other variables eg weight, aerodynamics, gearing...etc.
However when we are talking about cars that weigh almost the same give or take 300lb, ultimately it is torque!! Get a dyno and look at the powerband of a lightly modded (BPU) Gs-T vs a well modded 3800 NA...be it on a FWD/RWD platform...you will begin to notice a trend...oh yes the 3800 packs gobs of low-end torque however the powerband ends @ about 6000-6400 RPMs give or take and it isn't making anymore beyond what the Cam* "design"...so say we use stock values 5800-5900 RPMs, oh did I mention the graph looks like a pancake!! Now take a look at the graph of the accompanying 'clips with even another 1000-1500 RPMs to play with...do you notice a more pronounced/peaky/broader graph...it is called "Area under the curve"...it matters a whole lot, you can thank turbochargers for that!!

[ September 05, 2003: Message edited by: nocutt ]</p>

[Swift_3800_F-Body]

Hmm well i guess there is to many variables to say that certain engines make this and that. I guess each setup is unique.

[ September 08, 2003: Message edited by: Swift_3800_F-Body ]</p>