3400 Modified or 3400 Hybrid

[IsaacHayes]

3500 heads are pretty good from the factory. They have a lot of velocity, port it too much and that drops, and so does power. Bigger is not always better. You can clean them up and gasket match but be careful you can do more harm that good if you hog them out. I would port the 3500 upper to 3400 gaskets at least or 3500 gaskets and then port the lower to match and taper down for sure though. You want a funnel effect. LX5 65mm TB works great on the 3500 upper.

[sanjay]

I'd go with the 3400/3500 hybrid and 65mm tb. Ben at WOT-TECH has run some simulations and a stock 3400 has like 176 crank hp, but a stock 3400 with stock 3500 heads and a 65 mm tb has around 213 crank hp. Thats a 37 crank hp increase.
Now if you have a stock 3400 with street ported 3500 top end (heads, lim, and uim) and 65mm tb, you should have around 238 hp at the crank while bumping the power range up 1000 rpm. How does that sond?

Am I the only person tha thinks that 238 Hp is a little optomistic on the stock cam?? I'm thinking 220 tops..

I'm building a similar setup but I'm using 3.4 RWD pistons and a 62mm TB for now and going to a 65 later if it will help. I wasn't going to port the heads or LIM because I don't think it will be help much on a stock cam but if it by porting the heads & LIM I get close to 250 HP I'm all for it. Can anyone actually confirm that porting will give a significant gain on with a stock cam??

[asylummotorsports]

The TH-125 if built right can handle about anything a 3400 in most any incarnation can throw at it.

But you need a guy who knows what he is doing.

Jeff at Engineered Performance can help you with this as far as LSD's and gear ratio combinations are concerned. (He can be alittle hard to get ahold of, but be patient. It's worth it)

After that a good builder and the right converter is important.

If you need more info on this contact me at my e-mail (asylummotorsports@yahoo.ca) and I'll do my best to direct you in the right direction.



AND the stock ignition is MORE than adequate! It's one of the few things GM did VERY WELL!

[ZeeTwentyFour]

I'm kinda bumping/hijacking this to see where your at.

I just got myself a 3400 and will be starting to build it up hopefully the same way sidewinder is. I got some questions though. I haven't decided yet if I'm going to a 5 speed swap or not and was wondering if a Th-125 would be able to handle this kind of power?

[Sidewinder]

Sounds good! Can't wait to get started.

[IsaacHayes]

Hybrid with cam will need bigger injectors. Stock ignition will be fine, even boosted/etc. It's very strong stock.

[bszopi]

Stock ignition will be fine.

[Sidewinder]

I was just thinking, and there is a portion of this build I haven't fully considered and really should. So I'm going to ask about it now.

2 things: Ignition and Fuel Delivery.

For the hybrid with a cam, would I need to upgrade anything with the ignition, and even if I don't should I just do it anyway? Its something I have looked at briefly but I am not sure where and what parts I should get.

Secondly, will the stock injectors provide enough fuel or do I need to upgrade to L67 injectors or something similar?

[Sidewinder]

Yeah I'll have to do some research into whether the F-Body seyup will be able to work or not. I'll definitely look into it though.

As for the headers, I may do those after the fact, because really the engine needs to be in the car to make sure they will fit. I think I can modify the firewall while the engine is out though to make my life easier.

I plan on doing a similar if not the same swap some time this summer into my cavalier. I am very interested to see how all of this turns out so be sure to post updates

I will keep you updated, I'm not sure if I will be able to get the engine in this summer, but hopefully it will be finished. I'll keep you updated on progress.

[ZeeTwentyFour]

I plan on doing a similar if not the same swap some time this summer into my cavalier. I am very interested to see how all of this turns out so be sure to post updates

[IsaacHayes]

Yeah I dont know if your spindles will bolt up or not, or if you can swap to newer ones... berettas, and sunfires can swap to the grand am ones but then we gotta change wheel bearings and bolt pattern and outter axle... But it can be made to work...

You could just get the motor in, and hold off on exhaust and then do it all at once too. It would be restrictive but then you could do headers and full exhaust all at once and boom big power increase. If I had a car that fit headers without re-working the headers I would have them.

[Sidewinder]

Alright that sounds like a good idea to me, I have heard the sound a cam make on the hybrid from the Pinky Project Thread) and it does sound fantastic. I also want to do a full exhaust all at once, it is just easier that way. For the time being I'm just using the dual exhaust system off my Z34. I think I'm going to use the 3400 manifolds and have a new downpipe made.

I have thought about that, and I plan on getting one ahead of time before I actually buy the engine. Actually I plan it to be the first mod I buy this summer, I was talking to my friend and he wants to get rid of his for cheap. I'm also thinking of swapping to a 97 PCM to unlock a few more of the tables for tuning.

As for the brakes, I'll have to research that. Last I heard the F-Body brakes won't work on the 1.5 Gen Lumina/Monte as there are difference that don't allow it to fit, but I could be wrong about that. I do have 17inch rims I ride on in the summer, which should work with that, however my 15 inch steelies for my winter tires may have an issue with fitment.

[IsaacHayes]

I'd do the cam, because you gain a good amount of power, it makes your motor sound bad-ass, and it's not a mod you can do easily once the motor is in the car. If you want to hold off on stuff, hold off on the TB, just use the 3400 one for a while, that will save you some dough, and you can always bolt it on later. I'd probably do the headers and full exhaust all at once, when the motor is going in.

Also you will need a DHP to tune this beast... so figure in that cost...

Don't worry about drums in the rear. The front brakes do most of the work. You can upgrade to F-body brakes easily since you have the same hub pattern. You'd just need the calipers, bracket, rotors and possibly the knuckles from a newer W body but you may already have them.. Well, you'll need big wheels to clear it if you don't already have it.

[Sidewinder]

Well thats a good way to look at it. I think that answers the question of which route I should take. I suppose I could negate the S&S headers for know, though I would like to get it all at once. I need to get prices on everything as it stands right now anyway, so I'll just leave everything on the table until I figure that out.

Perhaps I should just work my budget around that...

I'm not sure if I want to go above 240CHP with this build though, I'm still running drums in the rear and I want to be sure my trans can handle the power. I'm not entirely sure though, I just don't want to overdo it right away (ie: I just want to be cautious).

However if I can reach my goal without getting a cam, I think I will drop it as it will save me roughly $600 (thats the cam, valve springs and pushrods to match) which I can use on my suspension. Suspension to me is just as important as horsepower numbers, and yes I actually do enjoy driving my Lumi, its pretty darn nimble for its size (it actually has a smaller turning radius than a neon, although that neon I drove was a POS) so I'd like to build that up.

I'll give that some thought though, and I'll start pondering the brakes next. I was planning on getting performance rotors for the front, and if necessary I will swap out for disks in the rear (assuming this is necessary, but I want to be safe as well).

[IsaacHayes]

Stock 3400 is around 185 crank, stock large port 3100 is 175 crank. This is with factory tunes and factory exhausts. 3500 LXP (non-vvt) is 200 crank.

For power, option2 with the 3500 plenum and a cam. I don't know why people think it's so hard to swap on (the plenum). I had all the stuff I needed and put it on in a day, and that was including putting on a different lower intake, which I had to take off and re-grind some more to clear my rockers!!