I will be starting my intake and exaust manifolds this week end, for my car which is a Galant VR4 and I will be running Wiseco pistons, Eagle rods, HKS 272/272 cams, 720cc injectors, Walbro pump, -8 lines, 60 Trim t3/t4 stage 3 .82ar Garrett turbo(50lbs/min) porting the head, SS valves, metal head gasket, DSM-perfromance FMIC, 3"DP-3.5" cat back exaust, MOST likely 80shot direct port N2o, AEM stand alone. Thats a taist of my set up, now I plan on the Intake manifold to have a 280cubic inch plenium with tappering runners about 6" long, with the stock throttle body, mild steel will be used and I plan on smothing the welds/joints on the inside as much as possable, what are your thoughts coments on this plan for the intake manifold( I really like the Forrester Racing Manifold) but I plan on making my own. Then the exaust manifold will be a almost equal length runner 321 stainless steel manifold, I plan on moving the turbo twards the passanger side of the car about 1" and twards the front of the car about 1" I will have to test fit and see how far I can go, I plan on using 1.5" ID or 1-5/8" ID Stainless Steel and mild steel flanges,
http://www.adfxracing.com/default.asp?action=product&vehicle_id=2&category_id=1
somthing similar to this design, simple to the point, what are your thoughts on the exaust manifold? Thanks for the feed back ither post or email me [email protected] thanks again.

moving the turbo is a very good idea. i started on an ex mani using the stock location and eventually gave up because there wasn't a good way of doing it in the limited space available. in the next week or two i'll be starting on my next ex mani for a T3 turbine, i'll move the turbo down and away from the motor as much as possible. this way i'll be able to actually make the runners close to the same length and i'll be able to utilize a real collector.

pictures of my original stainless exh. mani can be seen here:

http://www.streetdynamics.com/members/marshall/talon/exhaust manifold/exhaustmanifold.htm

i just finished my intake manifold. used a 220ci plenum, radiused 5" runners, and my favorite part - a center mounted TB. here's pics:

http://www.streetdynamics.com/members/marshall/talon/intakemanifold/intakemanifold.htm

feel free to email me with any questions whatsoever, always glad to help another diy'er.

marshall
[email protected]

well I just "finished" my mock manifold out of mild steel and 18ga mild steel tubing from napa.... that was way to much work but yours look good, I am ordering 321 stainless for burns stainless and I hope the material works better, thanks again.

intersesting design on the intake...

Marshall,
Those are very interesting manifolds. I gotta give both of you a huge thumbs up for constructing your own manifolds. That's pure DSM love! I did have one question though why have the throttle body mounted in the center of the intake mani? I assume that its for equal air flow to each runner, but isn't that going to require custom UIC pipe, throttle body elbow, and possible hood clearance problems? Congrats again on both of you for taking the initiative to DIY. Keep up the good work!

yes, yes, and yes. luckily i have no trouble getting mandrel bends (skydynamics.com) so the TB elbow and UIC tube weren't a problem.
i used some 1" long brass bushings and longer bolts from the hardware store to space my hood up enough. looks pretty mean now
i'll put pictures up on my website sometime soon.

marshall

The mod you made to your hood was to raise it for your throttle body and plumbing. Right? That sounds really interesting. I bet it looks really cool. I can't wait to see pics! That would be a really cool Home Depot mod that probably wouldn't cost alot. Any problems latching the hood with it sitting taller? Was I right about the throttle body being mounted in the center for better air flow?

if I were to put the TB there I would make the runners angle alittle down from the head so there would be a little more room for IC piping, I dont suppose you would try stock manifold vs you center TB manifold or try the TB in the "conventional" location vs your placement, ither dyno #s or the track would be good ways to tell unless Flow bench is an option, but the track you would see a time/trap change and could be done the same day, I will clean up my "mock" manifold and maybe post pics, I am still waiting for my external waist gate though. And when I get started on my intake manifold, hope that goes a little smoother but all in all not bad for my fist try. Thanks

yes, the center TB was for better distribution.
no problems latching the hood.
if i had done a better job measuring i could've made everything tuck under the hood nicely, but i was a bit off so i had to space the hood up. it wouldn't be any problem to angle the runners up a bit to make up for the inch needed.
unfortunately, while the car was sitting around for a month with the head off, my turbo decided to seize (?) still trying to figure that out. so i have not been able to get any sort of before/after impression. i'm replacing the 16g with a T3/T4 so i won't be able to really gauge the difference of the int. manifold because of all the other changes.
if i'm faster next year i'll be happy.

marshall

Holy cow!! I love you guys!! I've been wondering why someone would pay anywhere from $550 to over $1000 for something that a halfway intelligent and patient DIYer could make with some research, a welder and a few pipes and flanges. Who knows, yours may perform better than those "name brand" manifolds. I've been wanting to do this for a while but the wife would kill me if I spent more $ on the VR4.

My question is, what type of welder are you using? I've got access to a MIG but a $2000 TIG is not in the budget. Have you taken steps to insure that the exh mani won't crack because of the expansion properties of SS? or isn't that a concern?

Please keep the updates coming as I am living vicariously thru you guys.

One last thing... why the 60 trim?? wouldn't a 50 or 57 be a better match (or are you counting on the spray)?

i'm using a tig, i could see doing the intake manifold with a mig (assuming you're using steel, not aluminum) but not the exhaust manifold. you'd be fixing more than boosting.
my exhaust manifold and turbo will be braced to the block. i'd like to put some slip fittings in before the collector, but i can't seem to make room for them...
for your last comment - i was torn between the 60 and 57 trim myself until i finally decided i liked the 57 better. but honestly i think either one would be a great wheel for serious boost.

marshall

way cool!hey is that case in back ground(ex. pics) a type 4?

marshall, where did you get the runners on the intake manifold? i was thinking about making my own too but i wasn't sure where to get runners that match the port's shape. or did you made it yourself with lot's of banging with a hammer on a pipe?

hammer/die to fit the end of the pipe is what I plan on doing, and I am using a MIG welder, I plan on 309wire(weld 321 to 321 or 321 to mild steel) I am getting my stuff from Burns Stainless, and I bought the 60trim due to the comp map, it has run a mid 10@130+, I went with the .82stage 3 exaust because of my plan to run a 80shot direct port wet N2o, and I think I will get full boost by ABOUT 4,500-4,600 off n2o. I do not think thats to laggy, you still get full boost in each gear, you dont boost around town all the time, and I like top end. Also the 60trim stg 3 .63ar was said to have signs of compressure surge (turbo spooling to quick and brings compressure into surge limit, its unstable can make banging/klunking noises, and appear to orbit in the comp housing as much as 1/4") so I hope the bigger AR will keep me from compressure surge. And I would think 16gauge stainless with no suports at all, so the manifold can expand and contract as needed, I know someone that had a T-4 60-1 on there toyota truck and with DP weighed 50lbs with no supports, ran the manifold all year no cracks, stainless 321 of course. And I got my turbo and 35/40mm waist gate w/ 1.35bar spring, for 725 shipped so I think I got a good deal.

autronic - i just used 2" tubing and squished the ends in a vice to get the port shape. it was a little more complicated than that, but you get the idea. the hammer and die would work better, but i was feeling too lazy to make the die...

hose - Lycoming IO-360.

Fabricate a bracket to bolt your DP to the factory location on the engine. That will support most of the weight of the turbo! Then you will be almost 100% sure the header wont crack!

Al

Originally posted by T6Rocket
Fabricate a bracket to bolt your DP to the factory location on the engine. That will support most of the weight of the turbo! Then you will be almost 100% sure the header wont crack!

Al

Click to expand...

The man has arrived!

anyone know where to buy pre-made Volocity stacks? if not I will have to come up with a way to flare the pipe here. Thanks.
[email protected]
or post here, thanks.

burnsstainless.com has a lot of nice piping, they may have what you need.

Al

I was buing my SS from them for my exaust manifold but was wondering if anyone knew where to buy pre made Volocity stacks(Intake manifold) If not o well. thanks

I would look in some of the Hot Rodding magazines since they do alot with carb and usually you will find velocity stacks there. I would see what kind of bore size you are looking for and look for some thing that will fit. Most dual webers can range from 40 mm all the way up to 54 mm, they usually supply a velocity stack kit for em. Holley might also be some one to look at.

OOOOHHHHHHH Now I have an idea. I thought I was nuts to think of makeing my oun intake but all the aftermarket ones are not that hard to make. HHHMMMM maybe I will get more use out of nt $2000 TIG welder.

I was thinking of making a intake manifold similiar to Marshall's. I was going to take it one step farther though. I was going to have the TB, then split into 2 pipes, run a bit, then into a plenum and then out into the 4 runners. It is pretty hard to explain. I was going to go down from where a stock plenum is instead of going up like he did. For my trial one I was going to block off the stock TB location and run 2 pipes into the bottom of the stock manifold, then put the TB below them. Kind of like a reverse collector on the exhaust of a motorcycle. 1 into 2 into 4, instead of 4 into 2 into like a motorcycle.

sounds very interesting. could you elaborate a bit more on the gains you're expecting with this type of manifold?

thanks,
marshall

I have no idea on numbers. If you think about flow, the stock TB is totally in the wrong spot (which you already figured out). Your solution still gives you more air into the middle 2 cylinders, but should be much better than stock. I am pretty sure the TB location is why the engine runs hottest in cyl #1. The Magnus type manifolds should be even worse than a stock one in this regard. They narrow down on the #1 end, thus speeding up the intake speed even more. The air doesn't want to make the 90 degree corner to go in the #4 cylinder, so it doesn't get as much air and runs richer, thus cooler. I don't think the manifold I want to build will add a ton of power, but I think it will even out the A/F ratio of all 4 cylinders much better. By doing that though, you should be able to tune even leaner and get more power.

have you thought about using a nice 4/1 collector and going 4-1 instead of 4-2-1? it seems that may distribute air even more equally, although getting all the runners to the same length would be a challenge.

man that would be a fun project.

marshall