Stich weld Mk3 Astra engine bay? C20 LET

[Vauxhall Jim]

Hi all

Ive heard stories about the chassis leg pulling away from the bulkhead on Astras with a C20 LET. Is this true? Im planning on fitting a standard power LET in spring and I dont want to destroy my car! I dont reallt want to weld the body of the car as its 100% mint and I dont want to be buring paint and seem sealer away.

Any advice would be great James

[xe_nova]

it will be fine. only sround 50hp difference between XE and LET

[dewismotorsport]

Let's be honest no one ever keeps a LET standard so while the engines out your gonna have to do it as they do need welding, over time it will give up on you otherwise

[eddgsiturbo]

i have had a 290+ bhp let in my mk3 for over a year now and have no probs as of yet, i have a front upper strut brace so i imagine that would help things a lil, i think if u stick to 250ish to 300, things should be ok i wanna get a lower strut brace aswell just 2 help a lil bit more. but i have never heard stories of front ends comin off astras yet.

[dewismotorsport]

Don't get me wrong the front end won't come off but the shell will flex under acceleration and deceleration and the power out of corners will have a detramental affect on handling so seam welding isn't just for keeping it together but to improve the overall peformance of the shell

[doge5644]

If the cars simply for road use it'll be absolutely fine without welding, theres a number of let astras running up to 300bhp flawlessly.

[BigTurk]

Your only going to have to paint the engine bay so it's probably worth doing as itl cause more problems if it does pull appart.

[Vauxhall Jim]

Thanks people so where will it need welding up? Never strengthened a shell before

[paddy>gsi/turbo]

a mk3 astra has a engine cradle, keeps front end stiff. havent seen a mk3 pull flitch away from bulkhead. mk2 astras do this as no cradle,

my opinion no need to weld up bay

[eddgsiturbo]

it all depends what power u want mate? i think 300bhp with strut brace will be ok, mk3s are a lot strongwer than mk2s as said above but every car has a limit, like i say mine has been fine and i do give it some sh*t, if it only for road use and occasional 1/4s i think it will be fine 2 be honest, but think they stitch weld the turrets, seems from turret 2 lights, chassis legs 2 bulk head, and lower arms. may be wrong? but also weldin weak points will make other areas weak aswell as it puts strain in other places.

[buzball]

It dont need doing

[timc20xe]

im going for about 450bhp in my astra and i havent welded it

[fennyLET]

Its not a Nova lmao lmao lmao

[daddy cav]

Don't think I've seen a thread with so many mixed opinions .

[GSIKING]

I'm currently strengthening my astra and could also do with as much info as possible as I'm not totally sure what needs to be welded. But I have to say I think I does need doing. Have a 3.2v6 fitted for the past 4-5 years and it started splitting in a few places but mainly legs to bulkhead

[nige-p]

I'm currently strengthening my astra and could also do with as much info as possible as I'm not totally sure what needs to be welded. But I have to say I think I does need doing. Have a 3.2v6 fitted for the past 4-5 years and it started splitting in a few places but mainly legs to bulkhead

any pictures of the said damage

[big e]

As above very interested to see the said damage..

[GSIKING]

these are the best pics i can get with the engine still in, ive got a second gsi that all the strenghtening work is being done to so when i take the all the engine and stuff out the other car i will get some better pics of the splitting issues

[GSIKING]

this is the one that im attempting to rebuild/restore.

[davecavcon]

looking good that!
im doing a mint mk2 BUT it is a base model not an injection model so it dosnt have the stronger box section at the front under the rad or the complete craddle only a half craddle so i thought id better seam it but im going to paint it so you cant see the welds.
im going to do the bulk head as well and fit a steering clamp brace as i need all the help i can get. ive also taken the battery tray out and am going to bolt it in so it will make fitting engines and gearboxes a lot easier in the future

it was 85bhp standard and is now going to 250bhp, its a good job there is NO rust anywhere.

[astradaryl]

my mk2 astra after a stich weld

[GSIKING]

anyone got more info and pics on chassis welding/strengthening?

[GSIKING]

did u both just weld the engine bay or do inside the car aswell?

[davecavcon]

i only did the engine bay as the car was mint and if it was an injection cav then i wouldnt have even done that as the inj model has a big thick solid front cross member and also it has longer subframe arms that bolt to the crossmember, where as the non inj models had a single skin 'u' channel cross member that was only for holding the radiator in and NO long subframe arms so the engine bay beefing was needed IMO.
im not really doing it for ultimate handling just to make sure the bulkhead dosnt split, (known on cav mk2's and also im putting PAS on) and to insure the 250bhp engine dosnt cause problems latter on
if i was after handling i would have done the whole car as well, im building a RWD mk2 cav and WILL be stitching the whole car for strength and handling